Milivojević, Sanja

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orcid::0000-0001-5458-2980
  • Milivojević, Sanja (35)
  • Prica, Sanja (28)
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Author's Bibliography

Increased hydraulic resistance in tubes of once-through boiler due to fouling: A case study of 650 MWe ligite fired unit

Stevanović, Vladimir ; Milivojević, Sanja; Petrović, Milan M.; Ilić, Milica

(Elsevier, 2023)

TY  - JOUR
AU  - Stevanović, Vladimir 
AU  - Milivojević, Sanja
AU  - Petrović, Milan M.
AU  - Ilić, Milica
PY  - 2023
UR  - https://machinery.mas.bg.ac.rs/handle/123456789/4441
AB  - The analysis of pressure changes in water and steam flow along the entire once-through steam boiler tube system at the 650 MWe lignite fired Unit was carried out after the long operational period of almost 30 years without a chemical cleaning of the pipe system. A significant increase of the hydraulic resistance was recorded in comparison to the design values in the evaporator tubes, both in the water heating zone and in the evaporation zone with the two-phase mixture flow. The cause of this adverse effect is the formation of a wavy surface of the magnetite layer deposited on the inner wall of tubes. The significantly increased absolute roughness on the inner wall of tubes was determined on the basis of measured pressure drops at sections of the tube system and numerical calculation performed with a thermal-hydraulic model of single-phase and two-phase water and steam tube flows. The model is based on the steam-water two-fluid model with mass, momentum and energy balance equations and mechanistic correlations for the steam-water interface transfer processes. The model is suitable for the single and two-phase flow parameters prediction in the span from subcritical to supercritical and near critical pressure conditions. Conducted calculations provide detailed insight in the fluid pressure, velocity and temperature change in the boiler tube system. After the long operational period the pressure drop in evaporating tubes almost doubles in comparison to the design values. The presented results are a support to boiler's design, operational procedures and maintenance.
PB  - Elsevier
T2  - Case Studies in Thermal Engineering
T1  - Increased hydraulic resistance in tubes of once-through boiler due to fouling: A case study of 650 MWe ligite fired unit
IS  - February
SP  - 102706
VL  - 42
DO  - 10.1016/j.csite.2023.102706
ER  - 
@article{
author = "Stevanović, Vladimir  and Milivojević, Sanja and Petrović, Milan M. and Ilić, Milica",
year = "2023",
abstract = "The analysis of pressure changes in water and steam flow along the entire once-through steam boiler tube system at the 650 MWe lignite fired Unit was carried out after the long operational period of almost 30 years without a chemical cleaning of the pipe system. A significant increase of the hydraulic resistance was recorded in comparison to the design values in the evaporator tubes, both in the water heating zone and in the evaporation zone with the two-phase mixture flow. The cause of this adverse effect is the formation of a wavy surface of the magnetite layer deposited on the inner wall of tubes. The significantly increased absolute roughness on the inner wall of tubes was determined on the basis of measured pressure drops at sections of the tube system and numerical calculation performed with a thermal-hydraulic model of single-phase and two-phase water and steam tube flows. The model is based on the steam-water two-fluid model with mass, momentum and energy balance equations and mechanistic correlations for the steam-water interface transfer processes. The model is suitable for the single and two-phase flow parameters prediction in the span from subcritical to supercritical and near critical pressure conditions. Conducted calculations provide detailed insight in the fluid pressure, velocity and temperature change in the boiler tube system. After the long operational period the pressure drop in evaporating tubes almost doubles in comparison to the design values. The presented results are a support to boiler's design, operational procedures and maintenance.",
publisher = "Elsevier",
journal = "Case Studies in Thermal Engineering",
title = "Increased hydraulic resistance in tubes of once-through boiler due to fouling: A case study of 650 MWe ligite fired unit",
number = "February",
pages = "102706",
volume = "42",
doi = "10.1016/j.csite.2023.102706"
}
Stevanović, V., Milivojević, S., Petrović, M. M.,& Ilić, M.. (2023). Increased hydraulic resistance in tubes of once-through boiler due to fouling: A case study of 650 MWe ligite fired unit. in Case Studies in Thermal Engineering
Elsevier., 42(February), 102706.
https://doi.org/10.1016/j.csite.2023.102706
Stevanović V, Milivojević S, Petrović MM, Ilić M. Increased hydraulic resistance in tubes of once-through boiler due to fouling: A case study of 650 MWe ligite fired unit. in Case Studies in Thermal Engineering. 2023;42(February):102706.
doi:10.1016/j.csite.2023.102706 .
Stevanović, Vladimir , Milivojević, Sanja, Petrović, Milan M., Ilić, Milica, "Increased hydraulic resistance in tubes of once-through boiler due to fouling: A case study of 650 MWe ligite fired unit" in Case Studies in Thermal Engineering, 42, no. February (2023):102706,
https://doi.org/10.1016/j.csite.2023.102706 . .

Boiling and Condensation in Two-Phase System Transients with Water Hammer

Milivojević, Sanja; Stevanović, Vladimir; Petrović, Milan M.; Milica, Ilić

(IntechOpen, 2023)

TY  - CHAP
AU  - Milivojević, Sanja
AU  - Stevanović, Vladimir
AU  - Petrović, Milan M.
AU  - Milica, Ilić
PY  - 2023
UR  - https://machinery.mas.bg.ac.rs/handle/123456789/7093
AB  - Water hammer in two-phase systems, induced by direct steam condensation on subcooled water or by separation of subcooled water column, results in the most intensive pipeline pressure surges. Amplitudes of pressure spikes along the course of these dangerous transients strongly depend on the condensation and evaporation rates. The present paper provides a literature overview of thermal-hydraulic models for the prediction of water hammer phenomenon in two-phase systems, together with an original mechanistic approach for the prediction of phase transition rates, based on the shape and size of vapor-liquid interfacial area and the phase transition potential expressed through vapor and liquid phase temperature difference. Available water hammer experimental conditions were numerically simulated with the new modeling approach. Driving parameters of boiling and condensation rates at the steam-water interfaces are evaluated, and a good agreement is shown between numerical results and experimental data of bulk two-phase flow parameters during water hammer transients.
PB  - IntechOpen
T2  - Advances in Boiling and Condensation [Working Title]
T1  - Boiling and Condensation in Two-Phase System Transients with Water Hammer
DO  - 10.5772/intechopen.110122
ER  - 
@inbook{
author = "Milivojević, Sanja and Stevanović, Vladimir and Petrović, Milan M. and Milica, Ilić",
year = "2023",
abstract = "Water hammer in two-phase systems, induced by direct steam condensation on subcooled water or by separation of subcooled water column, results in the most intensive pipeline pressure surges. Amplitudes of pressure spikes along the course of these dangerous transients strongly depend on the condensation and evaporation rates. The present paper provides a literature overview of thermal-hydraulic models for the prediction of water hammer phenomenon in two-phase systems, together with an original mechanistic approach for the prediction of phase transition rates, based on the shape and size of vapor-liquid interfacial area and the phase transition potential expressed through vapor and liquid phase temperature difference. Available water hammer experimental conditions were numerically simulated with the new modeling approach. Driving parameters of boiling and condensation rates at the steam-water interfaces are evaluated, and a good agreement is shown between numerical results and experimental data of bulk two-phase flow parameters during water hammer transients.",
publisher = "IntechOpen",
journal = "Advances in Boiling and Condensation [Working Title]",
booktitle = "Boiling and Condensation in Two-Phase System Transients with Water Hammer",
doi = "10.5772/intechopen.110122"
}
Milivojević, S., Stevanović, V., Petrović, M. M.,& Milica, I.. (2023). Boiling and Condensation in Two-Phase System Transients with Water Hammer. in Advances in Boiling and Condensation [Working Title]
IntechOpen..
https://doi.org/10.5772/intechopen.110122
Milivojević S, Stevanović V, Petrović MM, Milica I. Boiling and Condensation in Two-Phase System Transients with Water Hammer. in Advances in Boiling and Condensation [Working Title]. 2023;.
doi:10.5772/intechopen.110122 .
Milivojević, Sanja, Stevanović, Vladimir, Petrović, Milan M., Milica, Ilić, "Boiling and Condensation in Two-Phase System Transients with Water Hammer" in Advances in Boiling and Condensation [Working Title] (2023),
https://doi.org/10.5772/intechopen.110122 . .

Flexibility of power generation and possibilities for feasible upgrades of coal power plants: a case of the Electric Power Industry of Serbia

Ilić, Milica; Stevanović, Vladimir; Petrović, Milan M.; Milivojević, Sanja

(Beograd : Društvo termičara Srbije, 2023)

TY  - CONF
AU  - Ilić, Milica
AU  - Stevanović, Vladimir
AU  - Petrović, Milan M.
AU  - Milivojević, Sanja
PY  - 2023
UR  - https://machinery.mas.bg.ac.rs/handle/123456789/7090
AB  - This paper deals with current status and possibilities for feasible improvement of the flexibility of power generation fleet consisting of aged coal-fired power plants and hydro power plants. The analyses are done by use of well-established deterministic metrics - the normalized flexibility indicator for each power unit is evaluated accounting for ramp up and ramp down power rates as well as the unit operating range. The method is applied to the case of the Electric Power Industry of Serbia (EPS). As expected, hydro power units are highly flexible with normalized flexibility indicator reaching the values as high as 0.78 (on the scale from 0 to 1). The units in power plants fired with lignite are of low flexibility - especially the units with the greatest power where the flexibility indicator is well below 0.2. This issue can represent a serious constraint for operation of these units in conditions of variable demand and future implementation of renewable energy sources with intermittent power generation. 
In units of lignite fired power plants the operating range (formulated as difference between maximal and minimal net electric power) is a stronger limitation than the value of ramp up / down rate. Therefore, the efforts for flexibility enhancement focus on lowering of minimal or increase of unit maximal power. In literature various technical measures are considered for this purpose. Despite their undoubtably positive impact, some of these measures (for example, implementation of additional boiler or replacement of thick-wall by thin-wall parts) would represent such a drastic surgery for the aged lignite fired power fleet that they cannot be considered as feasible. For that reason, we analyse sophisticated technical measures which contribute to flexibility increase, but do not require too high retrofitting costs. The solutions are based on (i) advanced operational procedures for feedwater redistribution (ii) installation of additional economizers for recovery of flue gas heat and (iii) implementation of steam accumulators.
PB  - Beograd : Društvo termičara Srbije
C3  - International Conference "Power Plants 2023", Zlatibor, Serbia, 8-10. november 2023.
T1  - Flexibility of power generation and possibilities for feasible upgrades of coal power plants: a case of the Electric Power Industry of Serbia
EP  - 435
SP  - 426
UR  - https://hdl.handle.net/21.15107/rcub_machinery_7090
ER  - 
@conference{
author = "Ilić, Milica and Stevanović, Vladimir and Petrović, Milan M. and Milivojević, Sanja",
year = "2023",
abstract = "This paper deals with current status and possibilities for feasible improvement of the flexibility of power generation fleet consisting of aged coal-fired power plants and hydro power plants. The analyses are done by use of well-established deterministic metrics - the normalized flexibility indicator for each power unit is evaluated accounting for ramp up and ramp down power rates as well as the unit operating range. The method is applied to the case of the Electric Power Industry of Serbia (EPS). As expected, hydro power units are highly flexible with normalized flexibility indicator reaching the values as high as 0.78 (on the scale from 0 to 1). The units in power plants fired with lignite are of low flexibility - especially the units with the greatest power where the flexibility indicator is well below 0.2. This issue can represent a serious constraint for operation of these units in conditions of variable demand and future implementation of renewable energy sources with intermittent power generation. 
In units of lignite fired power plants the operating range (formulated as difference between maximal and minimal net electric power) is a stronger limitation than the value of ramp up / down rate. Therefore, the efforts for flexibility enhancement focus on lowering of minimal or increase of unit maximal power. In literature various technical measures are considered for this purpose. Despite their undoubtably positive impact, some of these measures (for example, implementation of additional boiler or replacement of thick-wall by thin-wall parts) would represent such a drastic surgery for the aged lignite fired power fleet that they cannot be considered as feasible. For that reason, we analyse sophisticated technical measures which contribute to flexibility increase, but do not require too high retrofitting costs. The solutions are based on (i) advanced operational procedures for feedwater redistribution (ii) installation of additional economizers for recovery of flue gas heat and (iii) implementation of steam accumulators.",
publisher = "Beograd : Društvo termičara Srbije",
journal = "International Conference "Power Plants 2023", Zlatibor, Serbia, 8-10. november 2023.",
title = "Flexibility of power generation and possibilities for feasible upgrades of coal power plants: a case of the Electric Power Industry of Serbia",
pages = "435-426",
url = "https://hdl.handle.net/21.15107/rcub_machinery_7090"
}
Ilić, M., Stevanović, V., Petrović, M. M.,& Milivojević, S.. (2023). Flexibility of power generation and possibilities for feasible upgrades of coal power plants: a case of the Electric Power Industry of Serbia. in International Conference "Power Plants 2023", Zlatibor, Serbia, 8-10. november 2023.
Beograd : Društvo termičara Srbije., 426-435.
https://hdl.handle.net/21.15107/rcub_machinery_7090
Ilić M, Stevanović V, Petrović MM, Milivojević S. Flexibility of power generation and possibilities for feasible upgrades of coal power plants: a case of the Electric Power Industry of Serbia. in International Conference "Power Plants 2023", Zlatibor, Serbia, 8-10. november 2023.. 2023;:426-435.
https://hdl.handle.net/21.15107/rcub_machinery_7090 .
Ilić, Milica, Stevanović, Vladimir, Petrović, Milan M., Milivojević, Sanja, "Flexibility of power generation and possibilities for feasible upgrades of coal power plants: a case of the Electric Power Industry of Serbia" in International Conference "Power Plants 2023", Zlatibor, Serbia, 8-10. november 2023. (2023):426-435,
https://hdl.handle.net/21.15107/rcub_machinery_7090 .

UTILIZATION OF THE FLUE GAS WASTE HEAT BY THE LOW-PRESSURE ECONOMIZER AT 350 MWE LIGNITE-FIRED POWER PLANT

Petrović, Milan M.; Stevanović, Vladimir; Milivojević, Sanja; Ilić, Milica

(Beograd : Društvo termičara Srbije, 2023)

TY  - CONF
AU  - Petrović, Milan M.
AU  - Stevanović, Vladimir
AU  - Milivojević, Sanja
AU  - Ilić, Milica
PY  - 2023
UR  - https://machinery.mas.bg.ac.rs/handle/123456789/7091
AB  - Potential for the waste heat utilization in coal-fired thermal power plants that are in operation for a long period is reflected in an increased temperature of the flue gas at the exit of the regenerative air heater. After a long period of operation, the flue gas temperature exceeds the design value and is around 170 °C. In thermal power plants where a flue gas desulphurization plant has been built, the flue gas must be cooled at the absorber inlet to approximately 70 °C due to the efficiency of the desulphurization process, and thus the waste heat is irreversibly lost to the environment. Given the large temperature difference between the flue gas temperature at the boiler outlet and the temperature at the absorber inlet, as well as the large flue gas flow, there is a significant potential for the utilization of this waste heat. This potential can be used to heat the condensate from the steam power plant condensate line, where due to reduced steam extractions from the low-pressure turbine, the unchanged steam unit power is maintained with the lower fresh steam flow rate or the production of electricity increases without additional fuel consumption. The paper presents a technical solution for the utilization of waste heat in a low-pressure economizer at the 350 MWe lignite-fired thermal power plant. The energy balancing of the steam unit with the installed low-pressure economizer was performed and the increase in net unit efficiency was determined by applying the described solution in relation to the design conditions. It is shown that the net efficiency of the steam unit increases by 1.06 percentage points. About 73 GWh of electricity is produced by the flue gas waste heat utilization, which gives an annual reduction in coal consumption of approximately 98,000 tons, as well as an annual reduction in CO2 emissions of approximately 72,000 tons.
PB  - Beograd : Društvo termičara Srbije
C3  - International Conference "Power Plants 2023", Zlatibor, Serbia, 8-10. November 2023.
T1  - UTILIZATION OF THE FLUE GAS WASTE HEAT BY THE LOW-PRESSURE ECONOMIZER AT 350 MWE LIGNITE-FIRED POWER PLANT
EP  - 680
SP  - 675
UR  - https://hdl.handle.net/21.15107/rcub_machinery_7091
ER  - 
@conference{
author = "Petrović, Milan M. and Stevanović, Vladimir and Milivojević, Sanja and Ilić, Milica",
year = "2023",
abstract = "Potential for the waste heat utilization in coal-fired thermal power plants that are in operation for a long period is reflected in an increased temperature of the flue gas at the exit of the regenerative air heater. After a long period of operation, the flue gas temperature exceeds the design value and is around 170 °C. In thermal power plants where a flue gas desulphurization plant has been built, the flue gas must be cooled at the absorber inlet to approximately 70 °C due to the efficiency of the desulphurization process, and thus the waste heat is irreversibly lost to the environment. Given the large temperature difference between the flue gas temperature at the boiler outlet and the temperature at the absorber inlet, as well as the large flue gas flow, there is a significant potential for the utilization of this waste heat. This potential can be used to heat the condensate from the steam power plant condensate line, where due to reduced steam extractions from the low-pressure turbine, the unchanged steam unit power is maintained with the lower fresh steam flow rate or the production of electricity increases without additional fuel consumption. The paper presents a technical solution for the utilization of waste heat in a low-pressure economizer at the 350 MWe lignite-fired thermal power plant. The energy balancing of the steam unit with the installed low-pressure economizer was performed and the increase in net unit efficiency was determined by applying the described solution in relation to the design conditions. It is shown that the net efficiency of the steam unit increases by 1.06 percentage points. About 73 GWh of electricity is produced by the flue gas waste heat utilization, which gives an annual reduction in coal consumption of approximately 98,000 tons, as well as an annual reduction in CO2 emissions of approximately 72,000 tons.",
publisher = "Beograd : Društvo termičara Srbije",
journal = "International Conference "Power Plants 2023", Zlatibor, Serbia, 8-10. November 2023.",
title = "UTILIZATION OF THE FLUE GAS WASTE HEAT BY THE LOW-PRESSURE ECONOMIZER AT 350 MWE LIGNITE-FIRED POWER PLANT",
pages = "680-675",
url = "https://hdl.handle.net/21.15107/rcub_machinery_7091"
}
Petrović, M. M., Stevanović, V., Milivojević, S.,& Ilić, M.. (2023). UTILIZATION OF THE FLUE GAS WASTE HEAT BY THE LOW-PRESSURE ECONOMIZER AT 350 MWE LIGNITE-FIRED POWER PLANT. in International Conference "Power Plants 2023", Zlatibor, Serbia, 8-10. November 2023.
Beograd : Društvo termičara Srbije., 675-680.
https://hdl.handle.net/21.15107/rcub_machinery_7091
Petrović MM, Stevanović V, Milivojević S, Ilić M. UTILIZATION OF THE FLUE GAS WASTE HEAT BY THE LOW-PRESSURE ECONOMIZER AT 350 MWE LIGNITE-FIRED POWER PLANT. in International Conference "Power Plants 2023", Zlatibor, Serbia, 8-10. November 2023.. 2023;:675-680.
https://hdl.handle.net/21.15107/rcub_machinery_7091 .
Petrović, Milan M., Stevanović, Vladimir, Milivojević, Sanja, Ilić, Milica, "UTILIZATION OF THE FLUE GAS WASTE HEAT BY THE LOW-PRESSURE ECONOMIZER AT 350 MWE LIGNITE-FIRED POWER PLANT" in International Conference "Power Plants 2023", Zlatibor, Serbia, 8-10. November 2023. (2023):675-680,
https://hdl.handle.net/21.15107/rcub_machinery_7091 .

Numerical Prediction of Refrigerant-Oil Two-Phase Flow from The Scroll Compressor Discharge to the Suction Side via the Back Pressure Chamber

Stevanović, Vladimir; Petrović, Milan M.; Ćućuz, Stojan; Milivojević, Sanja; Ilić, Milica

(MDPI, Basel, Switzerland, 2023)

TY  - JOUR
AU  - Stevanović, Vladimir
AU  - Petrović, Milan M.
AU  - Ćućuz, Stojan
AU  - Milivojević, Sanja
AU  - Ilić, Milica
PY  - 2023
UR  - https://machinery.mas.bg.ac.rs/handle/123456789/7642
AB  - Оil lubricates the contact of the orbiting and stationary scroll in the refrigerant scroll compressor, while the sealing between the scrolls is achieved by the refrigerant vapour pressure in the sealed back pressure chamber. The back pressure should be adjusted by the refrigerant-oil two-phase flow from the oil separator at the compressor discharge to the back pressure chamber and the refrigerant-oil flow from the back pressure chamber to the compressor suction side. Both flows are conducted through connecting tubes with corresponding high-pressure and low-pressure nozzles of small diameters. Models for the prediction of refrigerant-oil critical and subcritical flows through nozzles are developed and applied for the prediction of back pressure. The models are original since the slip between oil and refrigerant as well as the refrigerant solubility in oil are taken into account. The critical flow model is validated against experimental data available in the literature. The back pressure is predicted by equating the mass flow rates of refrigerant and oil two-phase mixtures through the high and low-pressure nozzles. The results show that the critical flow takes place through the high-pressure nozzle, while the subcritical flow through the low-pressure nozzle can also exist in cases with small pressure difference between the back pressure chamber and the compressor suction side. The refrigerant solubility in oil has a small influence on the critical and subcritical refrigerant-oil mixture mass flow rates, while the influence on the back pressure is more pronounced.
PB  - MDPI, Basel, Switzerland
T2  - Processes
T1  - Numerical Prediction of Refrigerant-Oil Two-Phase Flow from The Scroll Compressor Discharge to the Suction Side via the Back Pressure Chamber
IS  - 1
SP  - 6
VL  - 12
DO  - 10.3390/pr12010006
ER  - 
@article{
author = "Stevanović, Vladimir and Petrović, Milan M. and Ćućuz, Stojan and Milivojević, Sanja and Ilić, Milica",
year = "2023",
abstract = "Оil lubricates the contact of the orbiting and stationary scroll in the refrigerant scroll compressor, while the sealing between the scrolls is achieved by the refrigerant vapour pressure in the sealed back pressure chamber. The back pressure should be adjusted by the refrigerant-oil two-phase flow from the oil separator at the compressor discharge to the back pressure chamber and the refrigerant-oil flow from the back pressure chamber to the compressor suction side. Both flows are conducted through connecting tubes with corresponding high-pressure and low-pressure nozzles of small diameters. Models for the prediction of refrigerant-oil critical and subcritical flows through nozzles are developed and applied for the prediction of back pressure. The models are original since the slip between oil and refrigerant as well as the refrigerant solubility in oil are taken into account. The critical flow model is validated against experimental data available in the literature. The back pressure is predicted by equating the mass flow rates of refrigerant and oil two-phase mixtures through the high and low-pressure nozzles. The results show that the critical flow takes place through the high-pressure nozzle, while the subcritical flow through the low-pressure nozzle can also exist in cases with small pressure difference between the back pressure chamber and the compressor suction side. The refrigerant solubility in oil has a small influence on the critical and subcritical refrigerant-oil mixture mass flow rates, while the influence on the back pressure is more pronounced.",
publisher = "MDPI, Basel, Switzerland",
journal = "Processes",
title = "Numerical Prediction of Refrigerant-Oil Two-Phase Flow from The Scroll Compressor Discharge to the Suction Side via the Back Pressure Chamber",
number = "1",
pages = "6",
volume = "12",
doi = "10.3390/pr12010006"
}
Stevanović, V., Petrović, M. M., Ćućuz, S., Milivojević, S.,& Ilić, M.. (2023). Numerical Prediction of Refrigerant-Oil Two-Phase Flow from The Scroll Compressor Discharge to the Suction Side via the Back Pressure Chamber. in Processes
MDPI, Basel, Switzerland., 12(1), 6.
https://doi.org/10.3390/pr12010006
Stevanović V, Petrović MM, Ćućuz S, Milivojević S, Ilić M. Numerical Prediction of Refrigerant-Oil Two-Phase Flow from The Scroll Compressor Discharge to the Suction Side via the Back Pressure Chamber. in Processes. 2023;12(1):6.
doi:10.3390/pr12010006 .
Stevanović, Vladimir, Petrović, Milan M., Ćućuz, Stojan, Milivojević, Sanja, Ilić, Milica, "Numerical Prediction of Refrigerant-Oil Two-Phase Flow from The Scroll Compressor Discharge to the Suction Side via the Back Pressure Chamber" in Processes, 12, no. 1 (2023):6,
https://doi.org/10.3390/pr12010006 . .
1

Water hammer in two-phase systems - causes, mechanisms, consequences

Milivojević, Sanja

(Društvo procesnih inženjera, Savez mašinskih i elektrotehničkih inženjera i tehničara Srbije, 2023)

TY  - GEN
AU  - Milivojević, Sanja
PY  - 2023
UR  - https://machinery.mas.bg.ac.rs/handle/123456789/7653
AB  - Hidraulički udar u dvofaznom sistemu može biti značajno veći od udara u jednofaznom fluidnom sistemu. Njegova pojava može dovesti do havarije i ugrožavanja bezbednosti pogonskog osoblja u različitim termoenerge-tskim, termotehničkim i procesnim postrojenjima. Može nastati usled implozije pri intenzivnoj kondenzaciji pare na pothlađenoj tečnosti, pri kidanju stuba tečnosti ili usled ubrzanja diskretnih masa tečnosti, kada se međusobno sudaraju čepovi ili stubovi tečnosti ili dolazi do njihovog udara o zidove cevovoda, posuda ili armature. Do hidrauličkog udara u dvofaznom fluidnom sistemu je dolazilo u termoelektranama, nuklearnim elektranama, sistemima daljinskog grejanja, kotlarnicama i rashladnim sistemima sa amonijakom. Karakteristični primeri su puštanje u pogon parovoda koji nisu dobro drenirani nakon zastoja u radu ili remonta, direktno ispuštanje pare u bazen ispunjen hladnom tečnošću, kontakt pothlađene tečnosti i pare nakon otvaranja zaporne aramature, pad pritiska u napojnom rezervoaru i usisnom cevovodu napojne pumpe nakon njenog ispada. U sistemima sa hladnom vodom, nakon naglog zatvaranja ventila ili zasuna, pritisak iza pregradne armature opada, dolazi do kavitacije rastvorenog vazduha, a zatim i do kavitacije pare, što dovodi do raskidanja vodenog stuba. Reflektovani kompresioni talas pritiska dovodi do implozije gasne faze, što dovodi do povratnog hidrauličkog udara, praćenog naglim skokom pritiska. Modeliranje i numerička simulacija hidrauličkog udara u dvofaznom sistemu se pokazuju na primeru udara pothlađenog vodenog stuba pri intenzivnoj kondenzaciji pare. Razvijen je nestacionarni jednodimenzionalni termohidraulički model strujanja homogenog dvofaznog fluida. Bilansne jednačine mase, količine kretanja i energije su rešene primenom metode karakteristika. Razdelna površina između faza je određena praćenjem talasa entalpije i Lagranžeovim polinomom trećeg stepena za određivanje položaja razdelne površine između fiksnih numeričkih noda u strujnom polju. Primenjen je novi mehanistički pristup za predviđanje brzina faznog prelaza, zasnovan na obliku i veličini razdelne površine tečne i parne faze i termičke neravnoteže između faza. Razvijenim modelom je moguće predviđanje prostiranja talasa pritiska tokom hidrauličkog udara, kao i praćenje kretanja razdelne površine uz modeliranje faznog prelaza i nestacionarnog trenja. Model je validiran za dostupne eksperimentalne uslove hidrauličkog udara. Primećeno je značajno rasipanje eksperimentalnih podataka za iste uslove eksperimenta, što je posledica brzine promene faze i njene zavisnosti od koncentracije razdelne površine parne i tečne faze u blizini čela stuba tečnosti.
PB  - Društvo procesnih inženjera, Savez mašinskih i elektrotehničkih inženjera i tehničara Srbije
T2  - 36. Međunarodni kongres o procesnoj industriji – Procesing ’23
T1  - Water hammer in two-phase systems -  causes, mechanisms, consequences
UR  - https://hdl.handle.net/21.15107/rcub_machinery_7653
ER  - 
@misc{
author = "Milivojević, Sanja",
year = "2023",
abstract = "Hidraulički udar u dvofaznom sistemu može biti značajno veći od udara u jednofaznom fluidnom sistemu. Njegova pojava može dovesti do havarije i ugrožavanja bezbednosti pogonskog osoblja u različitim termoenerge-tskim, termotehničkim i procesnim postrojenjima. Može nastati usled implozije pri intenzivnoj kondenzaciji pare na pothlađenoj tečnosti, pri kidanju stuba tečnosti ili usled ubrzanja diskretnih masa tečnosti, kada se međusobno sudaraju čepovi ili stubovi tečnosti ili dolazi do njihovog udara o zidove cevovoda, posuda ili armature. Do hidrauličkog udara u dvofaznom fluidnom sistemu je dolazilo u termoelektranama, nuklearnim elektranama, sistemima daljinskog grejanja, kotlarnicama i rashladnim sistemima sa amonijakom. Karakteristični primeri su puštanje u pogon parovoda koji nisu dobro drenirani nakon zastoja u radu ili remonta, direktno ispuštanje pare u bazen ispunjen hladnom tečnošću, kontakt pothlađene tečnosti i pare nakon otvaranja zaporne aramature, pad pritiska u napojnom rezervoaru i usisnom cevovodu napojne pumpe nakon njenog ispada. U sistemima sa hladnom vodom, nakon naglog zatvaranja ventila ili zasuna, pritisak iza pregradne armature opada, dolazi do kavitacije rastvorenog vazduha, a zatim i do kavitacije pare, što dovodi do raskidanja vodenog stuba. Reflektovani kompresioni talas pritiska dovodi do implozije gasne faze, što dovodi do povratnog hidrauličkog udara, praćenog naglim skokom pritiska. Modeliranje i numerička simulacija hidrauličkog udara u dvofaznom sistemu se pokazuju na primeru udara pothlađenog vodenog stuba pri intenzivnoj kondenzaciji pare. Razvijen je nestacionarni jednodimenzionalni termohidraulički model strujanja homogenog dvofaznog fluida. Bilansne jednačine mase, količine kretanja i energije su rešene primenom metode karakteristika. Razdelna površina između faza je određena praćenjem talasa entalpije i Lagranžeovim polinomom trećeg stepena za određivanje položaja razdelne površine između fiksnih numeričkih noda u strujnom polju. Primenjen je novi mehanistički pristup za predviđanje brzina faznog prelaza, zasnovan na obliku i veličini razdelne površine tečne i parne faze i termičke neravnoteže između faza. Razvijenim modelom je moguće predviđanje prostiranja talasa pritiska tokom hidrauličkog udara, kao i praćenje kretanja razdelne površine uz modeliranje faznog prelaza i nestacionarnog trenja. Model je validiran za dostupne eksperimentalne uslove hidrauličkog udara. Primećeno je značajno rasipanje eksperimentalnih podataka za iste uslove eksperimenta, što je posledica brzine promene faze i njene zavisnosti od koncentracije razdelne površine parne i tečne faze u blizini čela stuba tečnosti.",
publisher = "Društvo procesnih inženjera, Savez mašinskih i elektrotehničkih inženjera i tehničara Srbije",
journal = "36. Međunarodni kongres o procesnoj industriji – Procesing ’23",
title = "Water hammer in two-phase systems -  causes, mechanisms, consequences",
url = "https://hdl.handle.net/21.15107/rcub_machinery_7653"
}
Milivojević, S.. (2023). Water hammer in two-phase systems -  causes, mechanisms, consequences. in 36. Međunarodni kongres o procesnoj industriji – Procesing ’23
Društvo procesnih inženjera, Savez mašinskih i elektrotehničkih inženjera i tehničara Srbije..
https://hdl.handle.net/21.15107/rcub_machinery_7653
Milivojević S. Water hammer in two-phase systems -  causes, mechanisms, consequences. in 36. Međunarodni kongres o procesnoj industriji – Procesing ’23. 2023;.
https://hdl.handle.net/21.15107/rcub_machinery_7653 .
Milivojević, Sanja, "Water hammer in two-phase systems -  causes, mechanisms, consequences" in 36. Međunarodni kongres o procesnoj industriji – Procesing ’23 (2023),
https://hdl.handle.net/21.15107/rcub_machinery_7653 .

Explosive boiling of water films based on molecular dynamics simulations: Effects of film thickness and substrate temperature

Ilić, Milica; Stevanović, Vladimir; Milivojević, Sanja; Petrović, Milan M.

(Elsevier, 2023)

TY  - JOUR
AU  - Ilić, Milica
AU  - Stevanović, Vladimir
AU  - Milivojević, Sanja
AU  - Petrović, Milan M.
PY  - 2023
UR  - https://machinery.mas.bg.ac.rs/handle/123456789/3953
AB  - This paper deals with investigations of mechanisms governing explosive boiling of water films on hot copper substrate with plain surface. The investigations are based on results of molecular dynamics (MD) simulations in which film thickness (7.5 nm, 17 nm and 25.5 nm) and substrate temperature (800 K, 700 K and 600 K) are set as parameters. Analyses of heating transients, which lead to explosive boiling event, are done comparing the following quantities for considered MD configurations: time instant of explosive boiling onset, dynamics of vapour generation, increase of water film thickness due to thermal expansion and vapour generation, evolution of water temperature as well as heat transfer from the copper substrate to the water film. These analyses have shown that explosive boiling onset is related neither to the value of substrate temperature nor to the film thickness in a straightforward way. The investigations of temperature and per atom energy in the water region near the heating substrate surface have revealed that beside thermal also mechanical mechanisms can play significant role in triggering of explosive boiling. The mechanical mechanisms, related to pressure wave propagation in liquid film, comprise occurrence of tensile stresses which induce / intensify generation of vapour phase in the near wall region. The obtained results show that thermal effects are dominant in cases with high substrate temperature and thick liquid films as in these configurations the water temperature reaches spinodal value and explosive boiling is triggered before expansion wave reaches the near wall region. In cases when water in the near wall region is strongly overheated (but well below spinodal temperature), tensile stresses induced by expansive wave propagation cause intensive vapour generation and contribute dominantly to occurrence of explosive boiling. Finally, in cases with lower substrate temperature and thin liquid films, an interplay of thermal and mechanical mechanisms leads to explosive boiling. Beside these, the disjoining pressure seems to play a role in cases with thin liquid films.
PB  - Elsevier
T2  - Applied Thermal Engineering
T1  - Explosive boiling of water films based on molecular dynamics simulations: Effects of film thickness and substrate temperature
IS  - February
SP  - 119749
VL  - 220
DO  - 10.1016/j.applthermaleng.2022.119749
ER  - 
@article{
author = "Ilić, Milica and Stevanović, Vladimir and Milivojević, Sanja and Petrović, Milan M.",
year = "2023",
abstract = "This paper deals with investigations of mechanisms governing explosive boiling of water films on hot copper substrate with plain surface. The investigations are based on results of molecular dynamics (MD) simulations in which film thickness (7.5 nm, 17 nm and 25.5 nm) and substrate temperature (800 K, 700 K and 600 K) are set as parameters. Analyses of heating transients, which lead to explosive boiling event, are done comparing the following quantities for considered MD configurations: time instant of explosive boiling onset, dynamics of vapour generation, increase of water film thickness due to thermal expansion and vapour generation, evolution of water temperature as well as heat transfer from the copper substrate to the water film. These analyses have shown that explosive boiling onset is related neither to the value of substrate temperature nor to the film thickness in a straightforward way. The investigations of temperature and per atom energy in the water region near the heating substrate surface have revealed that beside thermal also mechanical mechanisms can play significant role in triggering of explosive boiling. The mechanical mechanisms, related to pressure wave propagation in liquid film, comprise occurrence of tensile stresses which induce / intensify generation of vapour phase in the near wall region. The obtained results show that thermal effects are dominant in cases with high substrate temperature and thick liquid films as in these configurations the water temperature reaches spinodal value and explosive boiling is triggered before expansion wave reaches the near wall region. In cases when water in the near wall region is strongly overheated (but well below spinodal temperature), tensile stresses induced by expansive wave propagation cause intensive vapour generation and contribute dominantly to occurrence of explosive boiling. Finally, in cases with lower substrate temperature and thin liquid films, an interplay of thermal and mechanical mechanisms leads to explosive boiling. Beside these, the disjoining pressure seems to play a role in cases with thin liquid films.",
publisher = "Elsevier",
journal = "Applied Thermal Engineering",
title = "Explosive boiling of water films based on molecular dynamics simulations: Effects of film thickness and substrate temperature",
number = "February",
pages = "119749",
volume = "220",
doi = "10.1016/j.applthermaleng.2022.119749"
}
Ilić, M., Stevanović, V., Milivojević, S.,& Petrović, M. M.. (2023). Explosive boiling of water films based on molecular dynamics simulations: Effects of film thickness and substrate temperature. in Applied Thermal Engineering
Elsevier., 220(February), 119749.
https://doi.org/10.1016/j.applthermaleng.2022.119749
Ilić M, Stevanović V, Milivojević S, Petrović MM. Explosive boiling of water films based on molecular dynamics simulations: Effects of film thickness and substrate temperature. in Applied Thermal Engineering. 2023;220(February):119749.
doi:10.1016/j.applthermaleng.2022.119749 .
Ilić, Milica, Stevanović, Vladimir, Milivojević, Sanja, Petrović, Milan M., "Explosive boiling of water films based on molecular dynamics simulations: Effects of film thickness and substrate temperature" in Applied Thermal Engineering, 220, no. February (2023):119749,
https://doi.org/10.1016/j.applthermaleng.2022.119749 . .
11
8

Increased hydraulic resistance in tubes of once-through boiler due to fouling: a case study of 650 MWe ligite fired unit

Stevanović, Vladimir; Milivojević, Sanja; Petrović, Milan M.; Ilić, Milica

(Beograd : Savez mašinskih i elektrotehničkih inženjera i tehničara Srbije (SMEITS), 2022)

TY  - CONF
AU  - Stevanović, Vladimir
AU  - Milivojević, Sanja
AU  - Petrović, Milan M.
AU  - Ilić, Milica
PY  - 2022
UR  - https://machinery.mas.bg.ac.rs/handle/123456789/4511
AB  - The analysis of pressure changes in water and steam flow along the entire once-through steam 
boiler tube system at the 650 MWe lignite fired Unit was carried out after the long operational period 
of almost 30 years without a chemical cleaning of the pipe system. A significant increase of the hydraulic
resistance was recorded in comparison to the design values in the evaporator tubes, both in 
the water heating zone and in the evaporation zone with the two-phase mixture flow. The cause of 
this adverse effect is the formation of a wavy surface of the magnetite layer deposited on the inner 
wall of tubes. The significantly increased hydraulic roughness on the inner wall of tubes was determined
on the basis of measured pressure drops at sections of the tube system and numerical calculation
performed with a thermal-hydraulic model of single-phase and two-phase water and steam tube 
flows. The model is based on the steam-water two-fluid model with mass, momentum and energy 
balance equations and mechanistic correlations for the steam-water interface transfer processes. The 
model is suitable for the single and two-phase flow parameters prediction in the span from subcritical 
to supercritical and near critical pressure conditions. Conducted calculations provide detailed insight
in the fluid pressure, velocity and temperature change in the boiler tube system. After the long 
operational period the pressure drop in evaporating tubes almost doubles in comparison to the design 
values. The presented results are a support to boiler’s design, operational procedures and maintenance.
PB  - Beograd : Savez mašinskih i elektrotehničkih inženjera i tehničara Srbije (SMEITS)
C3  - 35. Međunarodni kongres o procesnoj industriji - Procesing 2022, Beograd, Srbija, 1-2. jun 2022.
T1  - Increased hydraulic resistance in tubes of once-through boiler due to fouling: a case study of 650 MWe ligite fired unit
UR  - https://hdl.handle.net/21.15107/rcub_machinery_4511
ER  - 
@conference{
author = "Stevanović, Vladimir and Milivojević, Sanja and Petrović, Milan M. and Ilić, Milica",
year = "2022",
abstract = "The analysis of pressure changes in water and steam flow along the entire once-through steam 
boiler tube system at the 650 MWe lignite fired Unit was carried out after the long operational period 
of almost 30 years without a chemical cleaning of the pipe system. A significant increase of the hydraulic
resistance was recorded in comparison to the design values in the evaporator tubes, both in 
the water heating zone and in the evaporation zone with the two-phase mixture flow. The cause of 
this adverse effect is the formation of a wavy surface of the magnetite layer deposited on the inner 
wall of tubes. The significantly increased hydraulic roughness on the inner wall of tubes was determined
on the basis of measured pressure drops at sections of the tube system and numerical calculation
performed with a thermal-hydraulic model of single-phase and two-phase water and steam tube 
flows. The model is based on the steam-water two-fluid model with mass, momentum and energy 
balance equations and mechanistic correlations for the steam-water interface transfer processes. The 
model is suitable for the single and two-phase flow parameters prediction in the span from subcritical 
to supercritical and near critical pressure conditions. Conducted calculations provide detailed insight
in the fluid pressure, velocity and temperature change in the boiler tube system. After the long 
operational period the pressure drop in evaporating tubes almost doubles in comparison to the design 
values. The presented results are a support to boiler’s design, operational procedures and maintenance.",
publisher = "Beograd : Savez mašinskih i elektrotehničkih inženjera i tehničara Srbije (SMEITS)",
journal = "35. Međunarodni kongres o procesnoj industriji - Procesing 2022, Beograd, Srbija, 1-2. jun 2022.",
title = "Increased hydraulic resistance in tubes of once-through boiler due to fouling: a case study of 650 MWe ligite fired unit",
url = "https://hdl.handle.net/21.15107/rcub_machinery_4511"
}
Stevanović, V., Milivojević, S., Petrović, M. M.,& Ilić, M.. (2022). Increased hydraulic resistance in tubes of once-through boiler due to fouling: a case study of 650 MWe ligite fired unit. in 35. Međunarodni kongres o procesnoj industriji - Procesing 2022, Beograd, Srbija, 1-2. jun 2022.
Beograd : Savez mašinskih i elektrotehničkih inženjera i tehničara Srbije (SMEITS)..
https://hdl.handle.net/21.15107/rcub_machinery_4511
Stevanović V, Milivojević S, Petrović MM, Ilić M. Increased hydraulic resistance in tubes of once-through boiler due to fouling: a case study of 650 MWe ligite fired unit. in 35. Međunarodni kongres o procesnoj industriji - Procesing 2022, Beograd, Srbija, 1-2. jun 2022.. 2022;.
https://hdl.handle.net/21.15107/rcub_machinery_4511 .
Stevanović, Vladimir, Milivojević, Sanja, Petrović, Milan M., Ilić, Milica, "Increased hydraulic resistance in tubes of once-through boiler due to fouling: a case study of 650 MWe ligite fired unit" in 35. Međunarodni kongres o procesnoj industriji - Procesing 2022, Beograd, Srbija, 1-2. jun 2022. (2022),
https://hdl.handle.net/21.15107/rcub_machinery_4511 .

Povećanje energetske efikasnosti parnog bloka iskorišćenjem otpadne toplote dimnog gasa

Milivojević, Sanja; Stevanović, Vladimir; Petrović, Milan M.; Ilić, Milica

(Beograd : Savez mašinskih i elektrotehničkih inženjera Srbije (SMEITS), 2022)

TY  - JOUR
AU  - Milivojević, Sanja
AU  - Stevanović, Vladimir
AU  - Petrović, Milan M.
AU  - Ilić, Milica
PY  - 2022
UR  - https://machinery.mas.bg.ac.rs/handle/123456789/4504
PB  - Beograd : Savez mašinskih i elektrotehničkih inženjera Srbije (SMEITS)
T2  - Procesna tehnika
T1  - Povećanje energetske efikasnosti parnog bloka  iskorišćenjem otpadne toplote dimnog gasa
EP  - 37
IS  - 2
SP  - 30
VL  - Godina 33
UR  - https://hdl.handle.net/21.15107/rcub_machinery_4504
ER  - 
@article{
author = "Milivojević, Sanja and Stevanović, Vladimir and Petrović, Milan M. and Ilić, Milica",
year = "2022",
publisher = "Beograd : Savez mašinskih i elektrotehničkih inženjera Srbije (SMEITS)",
journal = "Procesna tehnika",
title = "Povećanje energetske efikasnosti parnog bloka  iskorišćenjem otpadne toplote dimnog gasa",
pages = "37-30",
number = "2",
volume = "Godina 33",
url = "https://hdl.handle.net/21.15107/rcub_machinery_4504"
}
Milivojević, S., Stevanović, V., Petrović, M. M.,& Ilić, M.. (2022). Povećanje energetske efikasnosti parnog bloka  iskorišćenjem otpadne toplote dimnog gasa. in Procesna tehnika
Beograd : Savez mašinskih i elektrotehničkih inženjera Srbije (SMEITS)., Godina 33(2), 30-37.
https://hdl.handle.net/21.15107/rcub_machinery_4504
Milivojević S, Stevanović V, Petrović MM, Ilić M. Povećanje energetske efikasnosti parnog bloka  iskorišćenjem otpadne toplote dimnog gasa. in Procesna tehnika. 2022;Godina 33(2):30-37.
https://hdl.handle.net/21.15107/rcub_machinery_4504 .
Milivojević, Sanja, Stevanović, Vladimir, Petrović, Milan M., Ilić, Milica, "Povećanje energetske efikasnosti parnog bloka  iskorišćenjem otpadne toplote dimnog gasa" in Procesna tehnika, Godina 33, no. 2 (2022):30-37,
https://hdl.handle.net/21.15107/rcub_machinery_4504 .

NUMERICAL SIMULATION OF WET FLUE GAS DESULPHURIZATION IN WET SPRAY ABSORBER

Petrović, Milan M.; Stevanović, Vladimir; Milivojević, Sanja; Ilić, Milica

(Društvo termičara Srbije, 2022)

TY  - CONF
AU  - Petrović, Milan M.
AU  - Stevanović, Vladimir
AU  - Milivojević, Sanja
AU  - Ilić, Milica
PY  - 2022
UR  - https://machinery.mas.bg.ac.rs/handle/123456789/4497
AB  - A concise one-dimensional thermal-hydraulic two-fluid model is presented for the 
numerical prediction of sulphur dioxide absorption from the flue gas onto drops of the waterlimestone
slurry in the vertical spray tower absorber. The model is based on mass, momentum and 
energy balance equations for each phase separately, i.e. downward falling droplets of water-limestone 
slurry and upward flowing flue gas. The sulphur dioxide content in the flue gas is predicted by a 
balance equation of the sulphur dioxide mass fraction in the flue gas. Interface transfer processes 
between the flue gas and the droplets are determined by closure laws. The obtained steady-state 
balance equations are transformed in a form suitable for a direct application of the numerical 
integration method for the system of ordinary differential equations. The developed thermal-hydraulic 
model is validated by comparing numerical results with available measured data at the large utility 
absorber. The presented results clearly show the dynamics of flue gas and droplets thermal-hydraulic 
processes and their influence on the absorption process. The influence of liquid-to-gas ratio and 
droplet diameter on sulphur dioxide removal efficiency has been investigated.
PB  - Društvo termičara Srbije
C3  - Industrijska energetika i zaštita životne sredine u zemljama Jugoistočne Evrope, IEEP 2022, November 8-10, 2022
T1  - NUMERICAL SIMULATION OF WET FLUE GAS DESULPHURIZATION  IN WET SPRAY ABSORBER
UR  - https://hdl.handle.net/21.15107/rcub_machinery_4497
ER  - 
@conference{
author = "Petrović, Milan M. and Stevanović, Vladimir and Milivojević, Sanja and Ilić, Milica",
year = "2022",
abstract = "A concise one-dimensional thermal-hydraulic two-fluid model is presented for the 
numerical prediction of sulphur dioxide absorption from the flue gas onto drops of the waterlimestone
slurry in the vertical spray tower absorber. The model is based on mass, momentum and 
energy balance equations for each phase separately, i.e. downward falling droplets of water-limestone 
slurry and upward flowing flue gas. The sulphur dioxide content in the flue gas is predicted by a 
balance equation of the sulphur dioxide mass fraction in the flue gas. Interface transfer processes 
between the flue gas and the droplets are determined by closure laws. The obtained steady-state 
balance equations are transformed in a form suitable for a direct application of the numerical 
integration method for the system of ordinary differential equations. The developed thermal-hydraulic 
model is validated by comparing numerical results with available measured data at the large utility 
absorber. The presented results clearly show the dynamics of flue gas and droplets thermal-hydraulic 
processes and their influence on the absorption process. The influence of liquid-to-gas ratio and 
droplet diameter on sulphur dioxide removal efficiency has been investigated.",
publisher = "Društvo termičara Srbije",
journal = "Industrijska energetika i zaštita životne sredine u zemljama Jugoistočne Evrope, IEEP 2022, November 8-10, 2022",
title = "NUMERICAL SIMULATION OF WET FLUE GAS DESULPHURIZATION  IN WET SPRAY ABSORBER",
url = "https://hdl.handle.net/21.15107/rcub_machinery_4497"
}
Petrović, M. M., Stevanović, V., Milivojević, S.,& Ilić, M.. (2022). NUMERICAL SIMULATION OF WET FLUE GAS DESULPHURIZATION  IN WET SPRAY ABSORBER. in Industrijska energetika i zaštita životne sredine u zemljama Jugoistočne Evrope, IEEP 2022, November 8-10, 2022
Društvo termičara Srbije..
https://hdl.handle.net/21.15107/rcub_machinery_4497
Petrović MM, Stevanović V, Milivojević S, Ilić M. NUMERICAL SIMULATION OF WET FLUE GAS DESULPHURIZATION  IN WET SPRAY ABSORBER. in Industrijska energetika i zaštita životne sredine u zemljama Jugoistočne Evrope, IEEP 2022, November 8-10, 2022. 2022;.
https://hdl.handle.net/21.15107/rcub_machinery_4497 .
Petrović, Milan M., Stevanović, Vladimir, Milivojević, Sanja, Ilić, Milica, "NUMERICAL SIMULATION OF WET FLUE GAS DESULPHURIZATION  IN WET SPRAY ABSORBER" in Industrijska energetika i zaštita životne sredine u zemljama Jugoistočne Evrope, IEEP 2022, November 8-10, 2022 (2022),
https://hdl.handle.net/21.15107/rcub_machinery_4497 .

Povećanje energetske efikasnosti parnog bloka iskorišćenjem otpadne toplote dimnog gasa

Milivojević, Sanja; Stevanović, Vladimir; Petrović, Milan M.; Ilić, Milica

(Beograd : Savez mašinskih i elektrotehničkih inženjera Srbije (SMEITS), 2021)

TY  - CONF
AU  - Milivojević, Sanja
AU  - Stevanović, Vladimir
AU  - Petrović, Milan M.
AU  - Ilić, Milica
PY  - 2021
UR  - https://machinery.mas.bg.ac.rs/handle/123456789/4520
AB  - U termoelektranama sa starijim projektnim rešenjima postoji značajan potencijal za iskorišćenje otpadne toplote 
dimnih gasova. Otpadna toplota dimnog gasa se može iskoristiti primenom zagrejača vode visokog pritiska (ZVVP) i 
niskog pritiska (ZVNP). U ovom radu je razmatrano rešenje sa ZVVP koji se napaja vоdоm sа pоtisnоg vоdа nаpојnе 
pumpе parnog bloka termoelektrane na ugalj, kao i primena ZVNP koji se napaja kondenzatom iz linije kondenzata 
niskog pritiska. U cilju poređenja energetskih efekata primene ZVVP i ZVNP, usvojene su iste površine oba 
razmenjivača. Minimalna temperatura kondenzata na ulazu u zagrejač vode je ograničena pojavom niskotemperaturne 
korozije. Povećanje električne snage na generatoru bruto ugradnjom ZVVP je 2,5 puta veće nego u slučaju sa ZVNP, a 
povećanje stepena korisnosti bloka bruto ugradnjom ZVNP je za 20% veće nego sa ZVVP. U radu su predstavljeni 
efekti ugradnje ZVVP koji se napaja hladnom napojnom vodom u termoelektrani "Nikola Tesla B".
PB  - Beograd : Savez mašinskih i elektrotehničkih inženjera Srbije (SMEITS)
C3  - 34. Međunarodni kongres o procesnoj industriji - Procesing 2021, Novi Sad, Srbija, 3-4. jun 2021
T1  - Povećanje energetske efikasnosti parnog bloka iskorišćenjem otpadne toplote dimnog gasa
UR  - https://hdl.handle.net/21.15107/rcub_machinery_4520
ER  - 
@conference{
author = "Milivojević, Sanja and Stevanović, Vladimir and Petrović, Milan M. and Ilić, Milica",
year = "2021",
abstract = "U termoelektranama sa starijim projektnim rešenjima postoji značajan potencijal za iskorišćenje otpadne toplote 
dimnih gasova. Otpadna toplota dimnog gasa se može iskoristiti primenom zagrejača vode visokog pritiska (ZVVP) i 
niskog pritiska (ZVNP). U ovom radu je razmatrano rešenje sa ZVVP koji se napaja vоdоm sа pоtisnоg vоdа nаpојnе 
pumpе parnog bloka termoelektrane na ugalj, kao i primena ZVNP koji se napaja kondenzatom iz linije kondenzata 
niskog pritiska. U cilju poređenja energetskih efekata primene ZVVP i ZVNP, usvojene su iste površine oba 
razmenjivača. Minimalna temperatura kondenzata na ulazu u zagrejač vode je ograničena pojavom niskotemperaturne 
korozije. Povećanje električne snage na generatoru bruto ugradnjom ZVVP je 2,5 puta veće nego u slučaju sa ZVNP, a 
povećanje stepena korisnosti bloka bruto ugradnjom ZVNP je za 20% veće nego sa ZVVP. U radu su predstavljeni 
efekti ugradnje ZVVP koji se napaja hladnom napojnom vodom u termoelektrani "Nikola Tesla B".",
publisher = "Beograd : Savez mašinskih i elektrotehničkih inženjera Srbije (SMEITS)",
journal = "34. Međunarodni kongres o procesnoj industriji - Procesing 2021, Novi Sad, Srbija, 3-4. jun 2021",
title = "Povećanje energetske efikasnosti parnog bloka iskorišćenjem otpadne toplote dimnog gasa",
url = "https://hdl.handle.net/21.15107/rcub_machinery_4520"
}
Milivojević, S., Stevanović, V., Petrović, M. M.,& Ilić, M.. (2021). Povećanje energetske efikasnosti parnog bloka iskorišćenjem otpadne toplote dimnog gasa. in 34. Međunarodni kongres o procesnoj industriji - Procesing 2021, Novi Sad, Srbija, 3-4. jun 2021
Beograd : Savez mašinskih i elektrotehničkih inženjera Srbije (SMEITS)..
https://hdl.handle.net/21.15107/rcub_machinery_4520
Milivojević S, Stevanović V, Petrović MM, Ilić M. Povećanje energetske efikasnosti parnog bloka iskorišćenjem otpadne toplote dimnog gasa. in 34. Međunarodni kongres o procesnoj industriji - Procesing 2021, Novi Sad, Srbija, 3-4. jun 2021. 2021;.
https://hdl.handle.net/21.15107/rcub_machinery_4520 .
Milivojević, Sanja, Stevanović, Vladimir, Petrović, Milan M., Ilić, Milica, "Povećanje energetske efikasnosti parnog bloka iskorišćenjem otpadne toplote dimnog gasa" in 34. Međunarodni kongres o procesnoj industriji - Procesing 2021, Novi Sad, Srbija, 3-4. jun 2021 (2021),
https://hdl.handle.net/21.15107/rcub_machinery_4520 .

New insights into physics of explosive water boiling derived from molecular dynamics simulations

Ilić, Milica; Stevanović, Vladimir; Milivojević, Sanja; Petrović, Milan M.

(Pergamon-Elsevier Science Ltd, Oxford, 2021)

TY  - JOUR
AU  - Ilić, Milica
AU  - Stevanović, Vladimir
AU  - Milivojević, Sanja
AU  - Petrović, Milan M.
PY  - 2021
UR  - https://machinery.mas.bg.ac.rs/handle/123456789/3609
AB  - In this paper the dynamics of explosive boiling of a 72 angstrom thick water film on the hot copper substrate with the plain surface is analysed. The analyses are based on the results of molecular dynamics (MD) simulations of the transient in which the thermostat temperature within the solid substrate is increased from 298 to 800K. The obtained results show that explosive boiling comprises several phases. The first phase involves rapid thermoacoustic pressure build-up in the near wall region due to intensive water heating and its volumetric expansion. The generated compression wave propagates through the liquid film reaching the peak value higher than critical water pressure. Due to reflection at the free film surface the original compression wave turns into an expansion wave. This event leads to a rapid pressure decrease and occurrence of tension stress. The second phase starts when the pressure enters the negative domain. This phase is accompanied with nucleation of vapour embryos and their subsequent growth in the superheated water layer in the near wall region. As the intensity of vapour phase generation is moderate, the liquid film in this phase is still exposed to tension. The stress recovery starts in the third phase when the water temperature in the near wall layer attains the spinodal value. This leads to a massive vaporization, nanobubble coalescence and thermal explosion, which causes spallation of the liquid film and lift-off of the liquid slug. The last phase is characterized by suppression of heat transfer by the expanding vapour layer. As a consequence, after reaching the maximum, the pressure decreases. This paper gives quantitative description and detailed insight into the mechanisms associated with each of the aforementioned phases.
PB  - Pergamon-Elsevier Science Ltd, Oxford
T2  - International Journal of Heat and Mass Transfer
T1  - New insights into physics of explosive water boiling derived from molecular dynamics simulations
SP  - 121141
VL  - 172
DO  - 10.1016/j.ijheatmasstransfer.2021.121141
ER  - 
@article{
author = "Ilić, Milica and Stevanović, Vladimir and Milivojević, Sanja and Petrović, Milan M.",
year = "2021",
abstract = "In this paper the dynamics of explosive boiling of a 72 angstrom thick water film on the hot copper substrate with the plain surface is analysed. The analyses are based on the results of molecular dynamics (MD) simulations of the transient in which the thermostat temperature within the solid substrate is increased from 298 to 800K. The obtained results show that explosive boiling comprises several phases. The first phase involves rapid thermoacoustic pressure build-up in the near wall region due to intensive water heating and its volumetric expansion. The generated compression wave propagates through the liquid film reaching the peak value higher than critical water pressure. Due to reflection at the free film surface the original compression wave turns into an expansion wave. This event leads to a rapid pressure decrease and occurrence of tension stress. The second phase starts when the pressure enters the negative domain. This phase is accompanied with nucleation of vapour embryos and their subsequent growth in the superheated water layer in the near wall region. As the intensity of vapour phase generation is moderate, the liquid film in this phase is still exposed to tension. The stress recovery starts in the third phase when the water temperature in the near wall layer attains the spinodal value. This leads to a massive vaporization, nanobubble coalescence and thermal explosion, which causes spallation of the liquid film and lift-off of the liquid slug. The last phase is characterized by suppression of heat transfer by the expanding vapour layer. As a consequence, after reaching the maximum, the pressure decreases. This paper gives quantitative description and detailed insight into the mechanisms associated with each of the aforementioned phases.",
publisher = "Pergamon-Elsevier Science Ltd, Oxford",
journal = "International Journal of Heat and Mass Transfer",
title = "New insights into physics of explosive water boiling derived from molecular dynamics simulations",
pages = "121141",
volume = "172",
doi = "10.1016/j.ijheatmasstransfer.2021.121141"
}
Ilić, M., Stevanović, V., Milivojević, S.,& Petrović, M. M.. (2021). New insights into physics of explosive water boiling derived from molecular dynamics simulations. in International Journal of Heat and Mass Transfer
Pergamon-Elsevier Science Ltd, Oxford., 172, 121141.
https://doi.org/10.1016/j.ijheatmasstransfer.2021.121141
Ilić M, Stevanović V, Milivojević S, Petrović MM. New insights into physics of explosive water boiling derived from molecular dynamics simulations. in International Journal of Heat and Mass Transfer. 2021;172:121141.
doi:10.1016/j.ijheatmasstransfer.2021.121141 .
Ilić, Milica, Stevanović, Vladimir, Milivojević, Sanja, Petrović, Milan M., "New insights into physics of explosive water boiling derived from molecular dynamics simulations" in International Journal of Heat and Mass Transfer, 172 (2021):121141,
https://doi.org/10.1016/j.ijheatmasstransfer.2021.121141 . .
1
18
14

Thermalhydraulics of once-through steam boiler tubes revisited

Stevanović, Vladimir; Milivojević, Sanja; Petrović, Milan M.; Ilić, Milica

(Department of Thermal Technology, Gliwice, Poland, Silesian University of Technology 2020, 2020)

TY  - CONF
AU  - Stevanović, Vladimir
AU  - Milivojević, Sanja
AU  - Petrović, Milan M.
AU  - Ilić, Milica
PY  - 2020
UR  - https://machinery.mas.bg.ac.rs/handle/123456789/4493
AB  - The analysis of pressure changes in water and steam flow along the entire once-through steam boiler 
tube system was carried out. An efficient advanced method is developed and presented for the 
prediction of once-through boiler thermalhydraulics, which is based on the steam-water two-fluid 
model with mass, momentum and energy balance equations and mechanistic correlations for the 
steam-water interface transfer processes. The model is suitable for the fluid flow parameters prediction 
in the span from single and two-phase flow conditions under subcritical operating conditions to 
supercritical and near critical flow conditions. Conducted calculations provide detailed insight in the 
fluid pressure, velocity and temperature change in the boiler tube system. The numerical results are 
validated by comparison with data measured at the boiler tube system. The thermalhydraulic analysis 
shows that a significant increase in hydraulic resistance occurs in boiler evaporator tubes, while this 
increase in the steam superheater tubes is lower. The increase of hydraulic resistance in the evaporator 
tubes, both in the water heating zone and in the evaporation zone with the two phase mixture flow is 
due to the fouling deposited on the inner wall of tubes. The pressure drop in evaporating tubes almost 
doubles in comparison to the design values after the long operational period. The presented results are 
a support to boiler’s design, operational procedures and maintenance.
PB  - Department of Thermal Technology, Gliwice, Poland, Silesian University of Technology 2020
C3  - Proceedings of the 6th International Conference on Contemporary Problems of Thermal Engineering - CPOTE 2020, online, Poland, September 21-24, 2020
T1  - Thermalhydraulics of once-through steam boiler tubes revisited
EP  - 328
SP  - 317
UR  - https://hdl.handle.net/21.15107/rcub_machinery_4493
ER  - 
@conference{
author = "Stevanović, Vladimir and Milivojević, Sanja and Petrović, Milan M. and Ilić, Milica",
year = "2020",
abstract = "The analysis of pressure changes in water and steam flow along the entire once-through steam boiler 
tube system was carried out. An efficient advanced method is developed and presented for the 
prediction of once-through boiler thermalhydraulics, which is based on the steam-water two-fluid 
model with mass, momentum and energy balance equations and mechanistic correlations for the 
steam-water interface transfer processes. The model is suitable for the fluid flow parameters prediction 
in the span from single and two-phase flow conditions under subcritical operating conditions to 
supercritical and near critical flow conditions. Conducted calculations provide detailed insight in the 
fluid pressure, velocity and temperature change in the boiler tube system. The numerical results are 
validated by comparison with data measured at the boiler tube system. The thermalhydraulic analysis 
shows that a significant increase in hydraulic resistance occurs in boiler evaporator tubes, while this 
increase in the steam superheater tubes is lower. The increase of hydraulic resistance in the evaporator 
tubes, both in the water heating zone and in the evaporation zone with the two phase mixture flow is 
due to the fouling deposited on the inner wall of tubes. The pressure drop in evaporating tubes almost 
doubles in comparison to the design values after the long operational period. The presented results are 
a support to boiler’s design, operational procedures and maintenance.",
publisher = "Department of Thermal Technology, Gliwice, Poland, Silesian University of Technology 2020",
journal = "Proceedings of the 6th International Conference on Contemporary Problems of Thermal Engineering - CPOTE 2020, online, Poland, September 21-24, 2020",
title = "Thermalhydraulics of once-through steam boiler tubes revisited",
pages = "328-317",
url = "https://hdl.handle.net/21.15107/rcub_machinery_4493"
}
Stevanović, V., Milivojević, S., Petrović, M. M.,& Ilić, M.. (2020). Thermalhydraulics of once-through steam boiler tubes revisited. in Proceedings of the 6th International Conference on Contemporary Problems of Thermal Engineering - CPOTE 2020, online, Poland, September 21-24, 2020
Department of Thermal Technology, Gliwice, Poland, Silesian University of Technology 2020., 317-328.
https://hdl.handle.net/21.15107/rcub_machinery_4493
Stevanović V, Milivojević S, Petrović MM, Ilić M. Thermalhydraulics of once-through steam boiler tubes revisited. in Proceedings of the 6th International Conference on Contemporary Problems of Thermal Engineering - CPOTE 2020, online, Poland, September 21-24, 2020. 2020;:317-328.
https://hdl.handle.net/21.15107/rcub_machinery_4493 .
Stevanović, Vladimir, Milivojević, Sanja, Petrović, Milan M., Ilić, Milica, "Thermalhydraulics of once-through steam boiler tubes revisited" in Proceedings of the 6th International Conference on Contemporary Problems of Thermal Engineering - CPOTE 2020, online, Poland, September 21-24, 2020 (2020):317-328,
https://hdl.handle.net/21.15107/rcub_machinery_4493 .

Upgrade of the thermal power plant flexibility by the steam accumulator

Stevanović, Vladimir; Petrović, Milan M.; Milivojević, Sanja; Ilić, Milica

(Pergamon-Elsevier Science Ltd, Oxford, 2020)

TY  - JOUR
AU  - Stevanović, Vladimir
AU  - Petrović, Milan M.
AU  - Milivojević, Sanja
AU  - Ilić, Milica
PY  - 2020
UR  - https://machinery.mas.bg.ac.rs/handle/123456789/3342
AB  - Thermal power plants are forced to operate under frequent load changes in energy systems with increased share of solar and wind power plants. These load changes increase thermal power plant aging and reduce their efficiency. Therefore, solutions for energy storage are sought in order to accumulate energy in periods of lower power demand and produce excess power in periods of increased demands. In the present paper the steam accumulator as the thermal energy storage device is applied in a 650 MWe coal-fired thermal power plant to increase its flexibility under the demand for the variable load changes. The steam accumulator is charged during periods of lower power demand, as during the night hours, and discharged during peak load demands. The steam accumulator with volume of 600 m(3) is charged with superheated steam (pressure 4.5 MPa and temperature 335 degrees C) extracted from the exit of high pressure steam turbine. The steam discharged from the steam accumulator replaces the turbine steam extraction for two low pressure heaters: a 59.5 MWt and a 54.6 MWt heater operating at 0.56 MPa and 0.23 MPa steam pressure. This replacement results in an increase of the steam flow rate through the turbine and the turbine power gain of 27.3 MWe during 27 min and 11.5 MWe for additional 13 min. The proposed solution of the steam accumulator installation in the power plant is a new design. The upgrade of power plant flexibility by steam accumulator is demonstrated.
PB  - Pergamon-Elsevier Science Ltd, Oxford
T2  - Energy Conversion and Management
T1  - Upgrade of the thermal power plant flexibility by the steam accumulator
SP  - 113271
VL  - 223
DO  - 10.1016/j.enconman.2020.113271
ER  - 
@article{
author = "Stevanović, Vladimir and Petrović, Milan M. and Milivojević, Sanja and Ilić, Milica",
year = "2020",
abstract = "Thermal power plants are forced to operate under frequent load changes in energy systems with increased share of solar and wind power plants. These load changes increase thermal power plant aging and reduce their efficiency. Therefore, solutions for energy storage are sought in order to accumulate energy in periods of lower power demand and produce excess power in periods of increased demands. In the present paper the steam accumulator as the thermal energy storage device is applied in a 650 MWe coal-fired thermal power plant to increase its flexibility under the demand for the variable load changes. The steam accumulator is charged during periods of lower power demand, as during the night hours, and discharged during peak load demands. The steam accumulator with volume of 600 m(3) is charged with superheated steam (pressure 4.5 MPa and temperature 335 degrees C) extracted from the exit of high pressure steam turbine. The steam discharged from the steam accumulator replaces the turbine steam extraction for two low pressure heaters: a 59.5 MWt and a 54.6 MWt heater operating at 0.56 MPa and 0.23 MPa steam pressure. This replacement results in an increase of the steam flow rate through the turbine and the turbine power gain of 27.3 MWe during 27 min and 11.5 MWe for additional 13 min. The proposed solution of the steam accumulator installation in the power plant is a new design. The upgrade of power plant flexibility by steam accumulator is demonstrated.",
publisher = "Pergamon-Elsevier Science Ltd, Oxford",
journal = "Energy Conversion and Management",
title = "Upgrade of the thermal power plant flexibility by the steam accumulator",
pages = "113271",
volume = "223",
doi = "10.1016/j.enconman.2020.113271"
}
Stevanović, V., Petrović, M. M., Milivojević, S.,& Ilić, M.. (2020). Upgrade of the thermal power plant flexibility by the steam accumulator. in Energy Conversion and Management
Pergamon-Elsevier Science Ltd, Oxford., 223, 113271.
https://doi.org/10.1016/j.enconman.2020.113271
Stevanović V, Petrović MM, Milivojević S, Ilić M. Upgrade of the thermal power plant flexibility by the steam accumulator. in Energy Conversion and Management. 2020;223:113271.
doi:10.1016/j.enconman.2020.113271 .
Stevanović, Vladimir, Petrović, Milan M., Milivojević, Sanja, Ilić, Milica, "Upgrade of the thermal power plant flexibility by the steam accumulator" in Energy Conversion and Management, 223 (2020):113271,
https://doi.org/10.1016/j.enconman.2020.113271 . .
40
44

Fluid dynamic forces in the main steam pipeline of thermal power plant upon stop valves closure

Stevanović, Vladimir; Milivojević, Sanja; Petrović, Milan M.

(Univerzitet u Beogradu - Institut za nuklearne nauke Vinča, Beograd, 2020)

TY  - JOUR
AU  - Stevanović, Vladimir
AU  - Milivojević, Sanja
AU  - Petrović, Milan M.
PY  - 2020
UR  - https://machinery.mas.bg.ac.rs/handle/123456789/3294
AB  - A steam turbine trip is followed by a prompt closure of stop valves in front of the turbine and consequently to a pressure rise in the main steam pipeline. This steam hammer transient leads to the generation of intensive fluid dynamic forces that act along the pipeline axis and induce additional dynamic loads on the main steam pipeline. It is a common practice to assume a simultaneous closure of all stop valves in the safety analysis of the main steam pipeline. In the present paper computer simulations and analyses of the fluid dynamic forces are performed for several scenarios that take into account the possibility of delayed closure of the stop valve in front of the turbine. The influence of the failure of the steam by-pass line opening is considered too. The results show that the delay of the stop valve closure increases the maximum intensity of fluid dynamic force in the pipeline segment in front of the stop valve and decreases the intensity of fluid dynamic forces in segments along the pipeline. The failure of the by-pass line to open leads to prolonged steam pressure and fluid dynamic forces oscillation in pipeline segments. The simulations were performed with the in-house computer code based on the method of characteristics for the solving of the hyperbolic system of PDE that represent the mass, momentum and energy balance equations of the 1-D, compressible and transient fluid-flow. The obtained results are a support to safety analyses of thermal power plants under transient conditions.
PB  - Univerzitet u Beogradu - Institut za nuklearne nauke Vinča, Beograd
T2  - Thermal Science
T1  - Fluid dynamic forces in the main steam pipeline of thermal power plant upon stop valves closure
EP  - 2224
IS  - 3
SP  - 2213
VL  - 24
DO  - 10.2298/TSCI190915426S
ER  - 
@article{
author = "Stevanović, Vladimir and Milivojević, Sanja and Petrović, Milan M.",
year = "2020",
abstract = "A steam turbine trip is followed by a prompt closure of stop valves in front of the turbine and consequently to a pressure rise in the main steam pipeline. This steam hammer transient leads to the generation of intensive fluid dynamic forces that act along the pipeline axis and induce additional dynamic loads on the main steam pipeline. It is a common practice to assume a simultaneous closure of all stop valves in the safety analysis of the main steam pipeline. In the present paper computer simulations and analyses of the fluid dynamic forces are performed for several scenarios that take into account the possibility of delayed closure of the stop valve in front of the turbine. The influence of the failure of the steam by-pass line opening is considered too. The results show that the delay of the stop valve closure increases the maximum intensity of fluid dynamic force in the pipeline segment in front of the stop valve and decreases the intensity of fluid dynamic forces in segments along the pipeline. The failure of the by-pass line to open leads to prolonged steam pressure and fluid dynamic forces oscillation in pipeline segments. The simulations were performed with the in-house computer code based on the method of characteristics for the solving of the hyperbolic system of PDE that represent the mass, momentum and energy balance equations of the 1-D, compressible and transient fluid-flow. The obtained results are a support to safety analyses of thermal power plants under transient conditions.",
publisher = "Univerzitet u Beogradu - Institut za nuklearne nauke Vinča, Beograd",
journal = "Thermal Science",
title = "Fluid dynamic forces in the main steam pipeline of thermal power plant upon stop valves closure",
pages = "2224-2213",
number = "3",
volume = "24",
doi = "10.2298/TSCI190915426S"
}
Stevanović, V., Milivojević, S.,& Petrović, M. M.. (2020). Fluid dynamic forces in the main steam pipeline of thermal power plant upon stop valves closure. in Thermal Science
Univerzitet u Beogradu - Institut za nuklearne nauke Vinča, Beograd., 24(3), 2213-2224.
https://doi.org/10.2298/TSCI190915426S
Stevanović V, Milivojević S, Petrović MM. Fluid dynamic forces in the main steam pipeline of thermal power plant upon stop valves closure. in Thermal Science. 2020;24(3):2213-2224.
doi:10.2298/TSCI190915426S .
Stevanović, Vladimir, Milivojević, Sanja, Petrović, Milan M., "Fluid dynamic forces in the main steam pipeline of thermal power plant upon stop valves closure" in Thermal Science, 24, no. 3 (2020):2213-2224,
https://doi.org/10.2298/TSCI190915426S . .

Numeričko istraživanje bazenskog ključanja i mehanizama razmene toplote na zagrejačkom zidu

Petrović, Milan M.; Stevanović, Vladimir; Ilić, Milica; Milivojević, Sanja

(Beograd : Savez mašinskih i elektrotehničkih inženjera Srbije (SMEITS), 2019)

TY  - CONF
AU  - Petrović, Milan M.
AU  - Stevanović, Vladimir
AU  - Ilić, Milica
AU  - Milivojević, Sanja
PY  - 2019
UR  - https://machinery.mas.bg.ac.rs/handle/123456789/4521
AB  - Ključanje je fenomen koji se odvija u procesnim, termoenergetskim i hemijskim postrojenjima i 
opremi. Precizno predviđanje koeficijenta prelaza toplote pri projektovanju i dimenzionisanju 
opreme u kojoj se odvija ključanje je veoma važno sa stanovišta sigurnosti i pouzdanosti rada. U 
ovom radu su prikazani rezultati numeričkog istraživanja bazenskog ključanja i mehanizama 
razmene toplote između zagrejačkog zida i ključajućeg fluida. Numeričko istraživanje je bazirano 
na formiranju modela za zagrejački zid kao i primeni modela dva fluida za dvofaznu mešavinu 
tečne i parne faze. Model zagrejačkog zida je zasnovan na rešavanju jednačine nestacionarnog 
provođenja toplote, dok je model dva fluida zasnovan na rešavanju jednačina bilansa mase, 
količine kretanja i energije za tečnu i parnu fazu posebno. Spregnutost ova dva modela je ostvarena 
uzimanjem u obzir mikro parametara, kao i odgovarajućim modeliranjem prenosa toplote na 
mestima gde nastaje mehur i prenosa toplote na tečni film koji okružuje mehurove. Razvijeni model 
uzima u obzir broj mesta nukleacije, prečnik mehura, vreme zadržavanja mehura na zagrejačkom 
zidu i ugao kvašenja kao parametre koji određuju dinamiku ključanja. Takođe, analizirano je kako 
ugao kvašenja, različite vrste materijala zagrejačkog zida pri različitim vrednostima toplotnih 
flukseva utiču na pregrejanje zida. Prikazani rezultati su upoređeni sa izmerenim vrednostima 
dostupnim u literaturi i ostvarena su zadovoljavajuća slaganja.
PB  - Beograd : Savez mašinskih i elektrotehničkih inženjera Srbije (SMEITS)
C3  - 32. Međunarodni kongres o procesnoj industriji - Procesing 2019, Beograd, Srbija, 30-31. maj 2019
T1  - Numeričko istraživanje bazenskog ključanja i mehanizama razmene toplote na zagrejačkom zidu
UR  - https://hdl.handle.net/21.15107/rcub_machinery_4521
ER  - 
@conference{
author = "Petrović, Milan M. and Stevanović, Vladimir and Ilić, Milica and Milivojević, Sanja",
year = "2019",
abstract = "Ključanje je fenomen koji se odvija u procesnim, termoenergetskim i hemijskim postrojenjima i 
opremi. Precizno predviđanje koeficijenta prelaza toplote pri projektovanju i dimenzionisanju 
opreme u kojoj se odvija ključanje je veoma važno sa stanovišta sigurnosti i pouzdanosti rada. U 
ovom radu su prikazani rezultati numeričkog istraživanja bazenskog ključanja i mehanizama 
razmene toplote između zagrejačkog zida i ključajućeg fluida. Numeričko istraživanje je bazirano 
na formiranju modela za zagrejački zid kao i primeni modela dva fluida za dvofaznu mešavinu 
tečne i parne faze. Model zagrejačkog zida je zasnovan na rešavanju jednačine nestacionarnog 
provođenja toplote, dok je model dva fluida zasnovan na rešavanju jednačina bilansa mase, 
količine kretanja i energije za tečnu i parnu fazu posebno. Spregnutost ova dva modela je ostvarena 
uzimanjem u obzir mikro parametara, kao i odgovarajućim modeliranjem prenosa toplote na 
mestima gde nastaje mehur i prenosa toplote na tečni film koji okružuje mehurove. Razvijeni model 
uzima u obzir broj mesta nukleacije, prečnik mehura, vreme zadržavanja mehura na zagrejačkom 
zidu i ugao kvašenja kao parametre koji određuju dinamiku ključanja. Takođe, analizirano je kako 
ugao kvašenja, različite vrste materijala zagrejačkog zida pri različitim vrednostima toplotnih 
flukseva utiču na pregrejanje zida. Prikazani rezultati su upoređeni sa izmerenim vrednostima 
dostupnim u literaturi i ostvarena su zadovoljavajuća slaganja.",
publisher = "Beograd : Savez mašinskih i elektrotehničkih inženjera Srbije (SMEITS)",
journal = "32. Međunarodni kongres o procesnoj industriji - Procesing 2019, Beograd, Srbija, 30-31. maj 2019",
title = "Numeričko istraživanje bazenskog ključanja i mehanizama razmene toplote na zagrejačkom zidu",
url = "https://hdl.handle.net/21.15107/rcub_machinery_4521"
}
Petrović, M. M., Stevanović, V., Ilić, M.,& Milivojević, S.. (2019). Numeričko istraživanje bazenskog ključanja i mehanizama razmene toplote na zagrejačkom zidu. in 32. Međunarodni kongres o procesnoj industriji - Procesing 2019, Beograd, Srbija, 30-31. maj 2019
Beograd : Savez mašinskih i elektrotehničkih inženjera Srbije (SMEITS)..
https://hdl.handle.net/21.15107/rcub_machinery_4521
Petrović MM, Stevanović V, Ilić M, Milivojević S. Numeričko istraživanje bazenskog ključanja i mehanizama razmene toplote na zagrejačkom zidu. in 32. Međunarodni kongres o procesnoj industriji - Procesing 2019, Beograd, Srbija, 30-31. maj 2019. 2019;.
https://hdl.handle.net/21.15107/rcub_machinery_4521 .
Petrović, Milan M., Stevanović, Vladimir, Ilić, Milica, Milivojević, Sanja, "Numeričko istraživanje bazenskog ključanja i mehanizama razmene toplote na zagrejačkom zidu" in 32. Međunarodni kongres o procesnoj industriji - Procesing 2019, Beograd, Srbija, 30-31. maj 2019 (2019),
https://hdl.handle.net/21.15107/rcub_machinery_4521 .

Efficiency and power upgrade at the aged lignite-fired power plant by flue gas waste heat utilization: High pressure versus low pressure economizer installation

Stevanović, Vladimir; Petrović, Milan M.; Wala, Tadeusz; Milivojević, Sanja; Ilić, Milica; Muszynski, Slawomir

(Pergamon-Elsevier Science Ltd, Oxford, 2019)

TY  - JOUR
AU  - Stevanović, Vladimir
AU  - Petrović, Milan M.
AU  - Wala, Tadeusz
AU  - Milivojević, Sanja
AU  - Ilić, Milica
AU  - Muszynski, Slawomir
PY  - 2019
UR  - https://machinery.mas.bg.ac.rs/handle/123456789/3059
AB  - A substantial potential exists for the recovery of flue gas waste heat at aged coal-fired power plants. High and low pressure economizers (HPE, LPE) can be applied for this purpose. Two cases of the feedwater supply to the HPE are considered: a supply of the "cold" feedwater taken from the feedwater pump discharge line and a supply of the "hot" feedwater taken after high pressure heaters. The LPE is fed by condensate taken from the low pressure condensate line. The heat transfer area of economizers is equal in all cases. The heat transfer rate of the LPE is maximized by the lowest possible condensate temperature at the economizer inlet, which is limited by the acid dew point temperature. The power upgrade by the HPE fed with the "cold" feedwater is by 2.5 times higher than in case with the LPE. The plant efficiency upgrade by the LPE is by 20% higher than in case with the HPE fed with "cold" feedwater. The HPE fed with the hot feedwater is not competitive. The presented overall benefits achieved by the HPE fed with the cold feedwater justify its implementation at the aged 620 MWe power plant.
PB  - Pergamon-Elsevier Science Ltd, Oxford
T2  - Energy
T1  - Efficiency and power upgrade at the aged lignite-fired power plant by flue gas waste heat utilization: High pressure versus low pressure economizer installation
SP  - 115980
VL  - 187
DO  - 10.1016/j.energy.2019.115980
ER  - 
@article{
author = "Stevanović, Vladimir and Petrović, Milan M. and Wala, Tadeusz and Milivojević, Sanja and Ilić, Milica and Muszynski, Slawomir",
year = "2019",
abstract = "A substantial potential exists for the recovery of flue gas waste heat at aged coal-fired power plants. High and low pressure economizers (HPE, LPE) can be applied for this purpose. Two cases of the feedwater supply to the HPE are considered: a supply of the "cold" feedwater taken from the feedwater pump discharge line and a supply of the "hot" feedwater taken after high pressure heaters. The LPE is fed by condensate taken from the low pressure condensate line. The heat transfer area of economizers is equal in all cases. The heat transfer rate of the LPE is maximized by the lowest possible condensate temperature at the economizer inlet, which is limited by the acid dew point temperature. The power upgrade by the HPE fed with the "cold" feedwater is by 2.5 times higher than in case with the LPE. The plant efficiency upgrade by the LPE is by 20% higher than in case with the HPE fed with "cold" feedwater. The HPE fed with the hot feedwater is not competitive. The presented overall benefits achieved by the HPE fed with the cold feedwater justify its implementation at the aged 620 MWe power plant.",
publisher = "Pergamon-Elsevier Science Ltd, Oxford",
journal = "Energy",
title = "Efficiency and power upgrade at the aged lignite-fired power plant by flue gas waste heat utilization: High pressure versus low pressure economizer installation",
pages = "115980",
volume = "187",
doi = "10.1016/j.energy.2019.115980"
}
Stevanović, V., Petrović, M. M., Wala, T., Milivojević, S., Ilić, M.,& Muszynski, S.. (2019). Efficiency and power upgrade at the aged lignite-fired power plant by flue gas waste heat utilization: High pressure versus low pressure economizer installation. in Energy
Pergamon-Elsevier Science Ltd, Oxford., 187, 115980.
https://doi.org/10.1016/j.energy.2019.115980
Stevanović V, Petrović MM, Wala T, Milivojević S, Ilić M, Muszynski S. Efficiency and power upgrade at the aged lignite-fired power plant by flue gas waste heat utilization: High pressure versus low pressure economizer installation. in Energy. 2019;187:115980.
doi:10.1016/j.energy.2019.115980 .
Stevanović, Vladimir, Petrović, Milan M., Wala, Tadeusz, Milivojević, Sanja, Ilić, Milica, Muszynski, Slawomir, "Efficiency and power upgrade at the aged lignite-fired power plant by flue gas waste heat utilization: High pressure versus low pressure economizer installation" in Energy, 187 (2019):115980,
https://doi.org/10.1016/j.energy.2019.115980 . .
24
27

Upgrade of the thermal power plant flexibility by the steam accumulator

Stevanović, Vladimir; Petrović, Milan M.; Milivojević, Sanja; Ilić, Milica

(Silesian University of Technology (PolSL), 2019)

TY  - CONF
AU  - Stevanović, Vladimir
AU  - Petrović, Milan M.
AU  - Milivojević, Sanja
AU  - Ilić, Milica
PY  - 2019
UR  - https://machinery.mas.bg.ac.rs/handle/123456789/4490
AB  - Thermal power plants are forced to operate under frequent load changes in energy 
systems with increased share of solar and wind power plants. These load changes 
increase thermal power plant aging and reduce their efficiency. Therefore, solutions for 
energy storage are sought in order to accumulate energy in periods of lower power 
demand and produce excess power in periods of increased demands. In the present 
paper the application of the steam accumulator is evaluated to provide the thermal 
energy storage in the coal-fired thermal power plant and to increase its flexibility under 
the demand for the variable load changes. The steam accumulator is charged during 
periods of lower power demand, as during the night hours, and discharged during peak 
load demands. The steam accumulator is charged by the steam extracted from the steam 
turbine. The steam discharged from the steam accumulator increases the steam flow rate 
through the turbine and the turbine power. Investigated are possible technical solutions 
with the steam accumulator installations in the power plant. The upgrade of power plant 
flexibility by steam accumulator is demonstrated. The corresponding operating 
parameters and energy benefits are calculated.
PB  - Silesian University of Technology (PolSL)
C3  - ECOS 2019 - Proceedings of the 32nd International Conference on Efficiency, Cost, Optimization, Simulation and Environmental Impact of Energy Systems, Wroclaw, Poland, June 23-28, 2019
T1  - Upgrade of the thermal power plant flexibility by the steam accumulator
EP  - 2960
SP  - 2951
UR  - https://hdl.handle.net/21.15107/rcub_machinery_4490
ER  - 
@conference{
author = "Stevanović, Vladimir and Petrović, Milan M. and Milivojević, Sanja and Ilić, Milica",
year = "2019",
abstract = "Thermal power plants are forced to operate under frequent load changes in energy 
systems with increased share of solar and wind power plants. These load changes 
increase thermal power plant aging and reduce their efficiency. Therefore, solutions for 
energy storage are sought in order to accumulate energy in periods of lower power 
demand and produce excess power in periods of increased demands. In the present 
paper the application of the steam accumulator is evaluated to provide the thermal 
energy storage in the coal-fired thermal power plant and to increase its flexibility under 
the demand for the variable load changes. The steam accumulator is charged during 
periods of lower power demand, as during the night hours, and discharged during peak 
load demands. The steam accumulator is charged by the steam extracted from the steam 
turbine. The steam discharged from the steam accumulator increases the steam flow rate 
through the turbine and the turbine power. Investigated are possible technical solutions 
with the steam accumulator installations in the power plant. The upgrade of power plant 
flexibility by steam accumulator is demonstrated. The corresponding operating 
parameters and energy benefits are calculated.",
publisher = "Silesian University of Technology (PolSL)",
journal = "ECOS 2019 - Proceedings of the 32nd International Conference on Efficiency, Cost, Optimization, Simulation and Environmental Impact of Energy Systems, Wroclaw, Poland, June 23-28, 2019",
title = "Upgrade of the thermal power plant flexibility by the steam accumulator",
pages = "2960-2951",
url = "https://hdl.handle.net/21.15107/rcub_machinery_4490"
}
Stevanović, V., Petrović, M. M., Milivojević, S.,& Ilić, M.. (2019). Upgrade of the thermal power plant flexibility by the steam accumulator. in ECOS 2019 - Proceedings of the 32nd International Conference on Efficiency, Cost, Optimization, Simulation and Environmental Impact of Energy Systems, Wroclaw, Poland, June 23-28, 2019
Silesian University of Technology (PolSL)., 2951-2960.
https://hdl.handle.net/21.15107/rcub_machinery_4490
Stevanović V, Petrović MM, Milivojević S, Ilić M. Upgrade of the thermal power plant flexibility by the steam accumulator. in ECOS 2019 - Proceedings of the 32nd International Conference on Efficiency, Cost, Optimization, Simulation and Environmental Impact of Energy Systems, Wroclaw, Poland, June 23-28, 2019. 2019;:2951-2960.
https://hdl.handle.net/21.15107/rcub_machinery_4490 .
Stevanović, Vladimir, Petrović, Milan M., Milivojević, Sanja, Ilić, Milica, "Upgrade of the thermal power plant flexibility by the steam accumulator" in ECOS 2019 - Proceedings of the 32nd International Conference on Efficiency, Cost, Optimization, Simulation and Environmental Impact of Energy Systems, Wroclaw, Poland, June 23-28, 2019 (2019):2951-2960,
https://hdl.handle.net/21.15107/rcub_machinery_4490 .

Calculation methodology and results of pipeline stress analysis, supports and steam pipeline hanging reconstruction for RA fresh steam pipeline at Power plant Kostolac B with increased fresh steam flow rate of 1060 t/h and new operational conditions

Živić, Dragan; Stevanović, Vladimir; Milivojević, Sanja; Petrović, Milan M.; Kesić, Đura

(University of Kragujevac Faculty of Engineering Department for Mechanical Constructions and Mechanization, 2019)

TY  - CONF
AU  - Živić, Dragan
AU  - Stevanović, Vladimir
AU  - Milivojević, Sanja
AU  - Petrović, Milan M.
AU  - Kesić, Đura
PY  - 2019
UR  - https://machinery.mas.bg.ac.rs/handle/123456789/4495
AB  - In order to reach designed power output of 2 x 348.5MW at two units of the Thermal 
power plant Kostolac B, a number of modernization and reconstruction activities are performed 
as well as static and dynamic fresh steam pipeline stress analysis. All overhauls and retrofits 
are conducted with aim to increase plant efficiency and reduce environmental pollution. In 
order to reach the design power, it was determined that it is necessary to increase the fresh 
steam flow rate from 1000 t/h to 1060 t/h. In this paper, the calculation methodology and 
obtained results of pipeline stress analysis of the fresh steam pipeline with new operational 
conditions are presented. Maximal fresh steam pipeline loads are determined in cases of 
transient conditions. The results of the pipeline stress analyses are presented together with the 
determined support loads and hangings. The steam pipeline operational parameter are analysed 
during trips and shut-offs, cold and hot start-ups and drainage conditions. Obtained results are 
support for the safety analyses and operational conditions determination.
PB  - University of Kragujevac Faculty of Engineering Department for Mechanical Constructions and Mechanization
C3  - Proceedings of the The 9th International Scientific Conference - IRMES 2019 Research and Development of Mechanical Elements and Systems, Kragujevac, Serbia, September 5-7, 2019
T1  - Calculation methodology and results of pipeline stress analysis, supports and steam pipeline hanging reconstruction for RA fresh steam pipeline at Power plant Kostolac B with increased fresh steam flow rate of 1060 t/h and new operational conditions
SP  - 66
UR  - https://hdl.handle.net/21.15107/rcub_machinery_4495
ER  - 
@conference{
author = "Živić, Dragan and Stevanović, Vladimir and Milivojević, Sanja and Petrović, Milan M. and Kesić, Đura",
year = "2019",
abstract = "In order to reach designed power output of 2 x 348.5MW at two units of the Thermal 
power plant Kostolac B, a number of modernization and reconstruction activities are performed 
as well as static and dynamic fresh steam pipeline stress analysis. All overhauls and retrofits 
are conducted with aim to increase plant efficiency and reduce environmental pollution. In 
order to reach the design power, it was determined that it is necessary to increase the fresh 
steam flow rate from 1000 t/h to 1060 t/h. In this paper, the calculation methodology and 
obtained results of pipeline stress analysis of the fresh steam pipeline with new operational 
conditions are presented. Maximal fresh steam pipeline loads are determined in cases of 
transient conditions. The results of the pipeline stress analyses are presented together with the 
determined support loads and hangings. The steam pipeline operational parameter are analysed 
during trips and shut-offs, cold and hot start-ups and drainage conditions. Obtained results are 
support for the safety analyses and operational conditions determination.",
publisher = "University of Kragujevac Faculty of Engineering Department for Mechanical Constructions and Mechanization",
journal = "Proceedings of the The 9th International Scientific Conference - IRMES 2019 Research and Development of Mechanical Elements and Systems, Kragujevac, Serbia, September 5-7, 2019",
title = "Calculation methodology and results of pipeline stress analysis, supports and steam pipeline hanging reconstruction for RA fresh steam pipeline at Power plant Kostolac B with increased fresh steam flow rate of 1060 t/h and new operational conditions",
pages = "66",
url = "https://hdl.handle.net/21.15107/rcub_machinery_4495"
}
Živić, D., Stevanović, V., Milivojević, S., Petrović, M. M.,& Kesić, Đ.. (2019). Calculation methodology and results of pipeline stress analysis, supports and steam pipeline hanging reconstruction for RA fresh steam pipeline at Power plant Kostolac B with increased fresh steam flow rate of 1060 t/h and new operational conditions. in Proceedings of the The 9th International Scientific Conference - IRMES 2019 Research and Development of Mechanical Elements and Systems, Kragujevac, Serbia, September 5-7, 2019
University of Kragujevac Faculty of Engineering Department for Mechanical Constructions and Mechanization., 66.
https://hdl.handle.net/21.15107/rcub_machinery_4495
Živić D, Stevanović V, Milivojević S, Petrović MM, Kesić Đ. Calculation methodology and results of pipeline stress analysis, supports and steam pipeline hanging reconstruction for RA fresh steam pipeline at Power plant Kostolac B with increased fresh steam flow rate of 1060 t/h and new operational conditions. in Proceedings of the The 9th International Scientific Conference - IRMES 2019 Research and Development of Mechanical Elements and Systems, Kragujevac, Serbia, September 5-7, 2019. 2019;:66.
https://hdl.handle.net/21.15107/rcub_machinery_4495 .
Živić, Dragan, Stevanović, Vladimir, Milivojević, Sanja, Petrović, Milan M., Kesić, Đura, "Calculation methodology and results of pipeline stress analysis, supports and steam pipeline hanging reconstruction for RA fresh steam pipeline at Power plant Kostolac B with increased fresh steam flow rate of 1060 t/h and new operational conditions" in Proceedings of the The 9th International Scientific Conference - IRMES 2019 Research and Development of Mechanical Elements and Systems, Kragujevac, Serbia, September 5-7, 2019 (2019):66,
https://hdl.handle.net/21.15107/rcub_machinery_4495 .

Hidrаulički udаr u dvоfаznоm sistеmu

Milivojević, Sanja

(Mašinski fakultet, Univerzitet u Beogradu, 2019)

TY  - BOOK
AU  - Milivojević, Sanja
PY  - 2019
UR  - https://machinery.mas.bg.ac.rs/handle/123456789/4483
PB  - Mašinski fakultet, Univerzitet u Beogradu
T1  - Hidrаulički udаr u dvоfаznоm sistеmu
EP  - 93
UR  - https://hdl.handle.net/21.15107/rcub_machinery_4483
ER  - 
@book{
author = "Milivojević, Sanja",
year = "2019",
publisher = "Mašinski fakultet, Univerzitet u Beogradu",
title = "Hidrаulički udаr u dvоfаznоm sistеmu",
pages = "93",
url = "https://hdl.handle.net/21.15107/rcub_machinery_4483"
}
Milivojević, S.. (2019). Hidrаulički udаr u dvоfаznоm sistеmu. 
Mašinski fakultet, Univerzitet u Beogradu..
https://hdl.handle.net/21.15107/rcub_machinery_4483
Milivojević S. Hidrаulički udаr u dvоfаznоm sistеmu. 2019;:null-93.
https://hdl.handle.net/21.15107/rcub_machinery_4483 .
Milivojević, Sanja, "Hidrаulički udаr u dvоfаznоm sistеmu" (2019),
https://hdl.handle.net/21.15107/rcub_machinery_4483 .

Povećanje hidrauličkog otpora u cevnom sistemu protočnog parnog kotla nakon višegodišnjeg rada

Stevanović, Vladimir; Milivojević, Sanja

(Društvo termičara Srbije, 2018)

TY  - CHAP
AU  - Stevanović, Vladimir
AU  - Milivojević, Sanja
PY  - 2018
UR  - https://machinery.mas.bg.ac.rs/handle/123456789/4523
AB  - Analiza promene pritiska u toku vode i vodene pare duž celog cevnog sistema protočnog 
parnog kotla, sprovedena u okviru projekta povećanja snage blokova B1 i B2, projektne snage 620 
MW, na Termoelektrani „Nikola Tesla B“, pokazala je da je tokom tridesetogodišnje eksploatacije, 
bez hemijskog čišćenja cevnog sistema, nastalo znatno povećanje hidrauličkog otpora u odnosu na 
projektom definisane uslove. Stoga je povećanje pada pritiska, od ulaza napojne vode u 
ekonomajzer kotla do izlaza pregrejane pare iz poslednjeg pregrejača pare na kotlu, postalo 
ograničenje povećanju protoka radnog fluida i snage parnog bloka. Nakon sprovedene analize 
izmerenih vrednosti pritiska na više mesta u okviru cevnog sistema kotla zaključeno je da je do 
značajnog povećanja hidrauličkog otpora došlo u isparivačkim cevima kotla, dok je ovo povećanje 
u cevima pregrejača pare znatno manje. U radu se pokazuje da do znatnog povećanja hidrauličkog 
otpora u isparivačkim cevima, kako u zoni zagrevanja vode, tako i u zoni isparavanja i strujanja 
dvofazne mešavine, dolazi usled stvaranja talasaste površine sloja magnetita koji se taloži na 
unutrašnjim zidovima cevi. Ovakva talasasta površina magnetitnog sloja nije uočena u cevima 
pregrejača pare, u kojima je povećanje hidrauličkog otpora u odnosu na projektne uslove znatno 
manje.
PB  - Društvo termičara Srbije
T2  - Međunarodna konferencija Elektrane 2018, Zlatibor, Srbija, 5-8. novembar 2018.
T1  - Povećanje hidrauličkog otpora u cevnom sistemu protočnog parnog kotla nakon višegodišnjeg rada
UR  - https://hdl.handle.net/21.15107/rcub_machinery_4523
ER  - 
@inbook{
author = "Stevanović, Vladimir and Milivojević, Sanja",
year = "2018",
abstract = "Analiza promene pritiska u toku vode i vodene pare duž celog cevnog sistema protočnog 
parnog kotla, sprovedena u okviru projekta povećanja snage blokova B1 i B2, projektne snage 620 
MW, na Termoelektrani „Nikola Tesla B“, pokazala je da je tokom tridesetogodišnje eksploatacije, 
bez hemijskog čišćenja cevnog sistema, nastalo znatno povećanje hidrauličkog otpora u odnosu na 
projektom definisane uslove. Stoga je povećanje pada pritiska, od ulaza napojne vode u 
ekonomajzer kotla do izlaza pregrejane pare iz poslednjeg pregrejača pare na kotlu, postalo 
ograničenje povećanju protoka radnog fluida i snage parnog bloka. Nakon sprovedene analize 
izmerenih vrednosti pritiska na više mesta u okviru cevnog sistema kotla zaključeno je da je do 
značajnog povećanja hidrauličkog otpora došlo u isparivačkim cevima kotla, dok je ovo povećanje 
u cevima pregrejača pare znatno manje. U radu se pokazuje da do znatnog povećanja hidrauličkog 
otpora u isparivačkim cevima, kako u zoni zagrevanja vode, tako i u zoni isparavanja i strujanja 
dvofazne mešavine, dolazi usled stvaranja talasaste površine sloja magnetita koji se taloži na 
unutrašnjim zidovima cevi. Ovakva talasasta površina magnetitnog sloja nije uočena u cevima 
pregrejača pare, u kojima je povećanje hidrauličkog otpora u odnosu na projektne uslove znatno 
manje.",
publisher = "Društvo termičara Srbije",
journal = "Međunarodna konferencija Elektrane 2018, Zlatibor, Srbija, 5-8. novembar 2018.",
booktitle = "Povećanje hidrauličkog otpora u cevnom sistemu protočnog parnog kotla nakon višegodišnjeg rada",
url = "https://hdl.handle.net/21.15107/rcub_machinery_4523"
}
Stevanović, V.,& Milivojević, S.. (2018). Povećanje hidrauličkog otpora u cevnom sistemu protočnog parnog kotla nakon višegodišnjeg rada. in Međunarodna konferencija Elektrane 2018, Zlatibor, Srbija, 5-8. novembar 2018.
Društvo termičara Srbije..
https://hdl.handle.net/21.15107/rcub_machinery_4523
Stevanović V, Milivojević S. Povećanje hidrauličkog otpora u cevnom sistemu protočnog parnog kotla nakon višegodišnjeg rada. in Međunarodna konferencija Elektrane 2018, Zlatibor, Srbija, 5-8. novembar 2018.. 2018;.
https://hdl.handle.net/21.15107/rcub_machinery_4523 .
Stevanović, Vladimir, Milivojević, Sanja, "Povećanje hidrauličkog otpora u cevnom sistemu protočnog parnog kotla nakon višegodišnjeg rada" in Međunarodna konferencija Elektrane 2018, Zlatibor, Srbija, 5-8. novembar 2018. (2018),
https://hdl.handle.net/21.15107/rcub_machinery_4523 .

Dynamics of wet flue gas desulphurization in spray absorber

Petrović, Milan M.; Stevanović, Vladimir; Janković, S.; Milivojević, Sanja

(University of Ljubljana, 2016)

TY  - CONF
AU  - Petrović, Milan M.
AU  - Stevanović, Vladimir
AU  - Janković, S.
AU  - Milivojević, Sanja
PY  - 2016
UR  - https://machinery.mas.bg.ac.rs/handle/123456789/2325
AB  - A concise one dimensional thermal-hydraulic two-fluid model is presented for the numerical prediction of sulphur dioxide absorption from the flue gas onto drops of the water-limestone slurry in the vertical spray tower absorber. The model is based on mass, momentum and energy balance equations for each phase separately, i.e. downward falling droplets of water-limestone slurry and upward flowing flue gas. The sulphur dioxide content in the flue gas is predicted by a balance equation of the sulphur dioxide mass fraction in the flue gas. Interface transfer processes between the flue gas and the droplets are determined by closure laws. The obtained steady-state balance equations are transformed in a form suitable for a direct application of the numerical integration method for the system of ordinary differential equations. The developed thermal-hydraulic model is validated by comparing numerical results with available measured data at the large utility absorber. The presented results clearly show the dynamics of flue gas and droplets thermal-hydraulic processes and their influence on the absorption process.
PB  - University of Ljubljana
C3  - ECOS 2016 - Proceedings of the 29th International Conference on Efficiency, Cost, Optimisation, Simu
T1  - Dynamics of wet flue gas desulphurization in spray absorber
UR  - https://hdl.handle.net/21.15107/rcub_machinery_2325
ER  - 
@conference{
author = "Petrović, Milan M. and Stevanović, Vladimir and Janković, S. and Milivojević, Sanja",
year = "2016",
abstract = "A concise one dimensional thermal-hydraulic two-fluid model is presented for the numerical prediction of sulphur dioxide absorption from the flue gas onto drops of the water-limestone slurry in the vertical spray tower absorber. The model is based on mass, momentum and energy balance equations for each phase separately, i.e. downward falling droplets of water-limestone slurry and upward flowing flue gas. The sulphur dioxide content in the flue gas is predicted by a balance equation of the sulphur dioxide mass fraction in the flue gas. Interface transfer processes between the flue gas and the droplets are determined by closure laws. The obtained steady-state balance equations are transformed in a form suitable for a direct application of the numerical integration method for the system of ordinary differential equations. The developed thermal-hydraulic model is validated by comparing numerical results with available measured data at the large utility absorber. The presented results clearly show the dynamics of flue gas and droplets thermal-hydraulic processes and their influence on the absorption process.",
publisher = "University of Ljubljana",
journal = "ECOS 2016 - Proceedings of the 29th International Conference on Efficiency, Cost, Optimisation, Simu",
title = "Dynamics of wet flue gas desulphurization in spray absorber",
url = "https://hdl.handle.net/21.15107/rcub_machinery_2325"
}
Petrović, M. M., Stevanović, V., Janković, S.,& Milivojević, S.. (2016). Dynamics of wet flue gas desulphurization in spray absorber. in ECOS 2016 - Proceedings of the 29th International Conference on Efficiency, Cost, Optimisation, Simu
University of Ljubljana..
https://hdl.handle.net/21.15107/rcub_machinery_2325
Petrović MM, Stevanović V, Janković S, Milivojević S. Dynamics of wet flue gas desulphurization in spray absorber. in ECOS 2016 - Proceedings of the 29th International Conference on Efficiency, Cost, Optimisation, Simu. 2016;.
https://hdl.handle.net/21.15107/rcub_machinery_2325 .
Petrović, Milan M., Stevanović, Vladimir, Janković, S., Milivojević, Sanja, "Dynamics of wet flue gas desulphurization in spray absorber" in ECOS 2016 - Proceedings of the 29th International Conference on Efficiency, Cost, Optimisation, Simu (2016),
https://hdl.handle.net/21.15107/rcub_machinery_2325 .
1

Dinamika i regulacija rada akumulatora pare

Petrović, Milan M.; Milivojević, Sanja; Stevanović, Vladimir

(Savez mašinskih i elektrotehničkih inženjera Srbije (SMEITS), 2015)

TY  - JOUR
AU  - Petrović, Milan M.
AU  - Milivojević, Sanja
AU  - Stevanović, Vladimir
PY  - 2015
UR  - https://machinery.mas.bg.ac.rs/handle/123456789/4505
PB  - Savez mašinskih i elektrotehničkih inženjera  Srbije (SMEITS)
T2  - Procesna tehnika
T1  - Dinamika i regulacija rada akumulatora pare
EP  - 27
IS  - 2
SP  - 20
VL  - Godina 27
UR  - https://hdl.handle.net/21.15107/rcub_machinery_4505
ER  - 
@article{
author = "Petrović, Milan M. and Milivojević, Sanja and Stevanović, Vladimir",
year = "2015",
publisher = "Savez mašinskih i elektrotehničkih inženjera  Srbije (SMEITS)",
journal = "Procesna tehnika",
title = "Dinamika i regulacija rada akumulatora pare",
pages = "27-20",
number = "2",
volume = "Godina 27",
url = "https://hdl.handle.net/21.15107/rcub_machinery_4505"
}
Petrović, M. M., Milivojević, S.,& Stevanović, V.. (2015). Dinamika i regulacija rada akumulatora pare. in Procesna tehnika
Savez mašinskih i elektrotehničkih inženjera  Srbije (SMEITS)., Godina 27(2), 20-27.
https://hdl.handle.net/21.15107/rcub_machinery_4505
Petrović MM, Milivojević S, Stevanović V. Dinamika i regulacija rada akumulatora pare. in Procesna tehnika. 2015;Godina 27(2):20-27.
https://hdl.handle.net/21.15107/rcub_machinery_4505 .
Petrović, Milan M., Milivojević, Sanja, Stevanović, Vladimir, "Dinamika i regulacija rada akumulatora pare" in Procesna tehnika, Godina 27, no. 2 (2015):20-27,
https://hdl.handle.net/21.15107/rcub_machinery_4505 .

Prediction and Control of Steam Accumulation

Stevanović, Vladimir; Petrović, Milan M.; Milivojević, Sanja; Maslovarić, Blaženka

(Taylor & Francis Inc, Philadelphia, 2015)

TY  - JOUR
AU  - Stevanović, Vladimir
AU  - Petrović, Milan M.
AU  - Milivojević, Sanja
AU  - Maslovarić, Blaženka
PY  - 2015
UR  - https://machinery.mas.bg.ac.rs/handle/123456789/2201
AB  - Steam accumulators are applied as buffers between steam generators and consumers in cases of different steam production and consumption rates. The application of the steam accumulator saves energy, reduces pressure fluctuations, and prevents aging of tubes and pressurized vessels in steam generators. In this paper, modes of the steam accumulator operation are analyzed and the general design of the steam accumulator control system is defined. Equilibrium and nonequilibrium thermodynamic models of the steam accumulator are presented with the aim of predicting the steam accumulator capacity and as support to the design of the control system. The equilibrium model is based on the mass and energy balance equations of the total water and steam content in the accumulator, while the nonequilibrium model is based on the mass and energy balance equations for each phase and closure laws of nonequilibrium evaporation and condensation rates. The steam accumulator pressure transients are simulated for constant steam charging and discharging flow rates, and the influence of the nonequilibrium condensation and evaporation rates on the steam accumulator capacity is shown. It is concluded that the commonly used equilibrium thermodynamic approach to the steam accumulator design does not provide accurate results in cases of rapid charging and discharging transients; therefore, there is a need for the application of the nonequilibrium approach.
PB  - Taylor & Francis Inc, Philadelphia
T2  - Heat Transfer Engineering
T1  - Prediction and Control of Steam Accumulation
EP  - 510
IS  - 5
SP  - 498
VL  - 36
DO  - 10.1080/01457632.2014.935226
ER  - 
@article{
author = "Stevanović, Vladimir and Petrović, Milan M. and Milivojević, Sanja and Maslovarić, Blaženka",
year = "2015",
abstract = "Steam accumulators are applied as buffers between steam generators and consumers in cases of different steam production and consumption rates. The application of the steam accumulator saves energy, reduces pressure fluctuations, and prevents aging of tubes and pressurized vessels in steam generators. In this paper, modes of the steam accumulator operation are analyzed and the general design of the steam accumulator control system is defined. Equilibrium and nonequilibrium thermodynamic models of the steam accumulator are presented with the aim of predicting the steam accumulator capacity and as support to the design of the control system. The equilibrium model is based on the mass and energy balance equations of the total water and steam content in the accumulator, while the nonequilibrium model is based on the mass and energy balance equations for each phase and closure laws of nonequilibrium evaporation and condensation rates. The steam accumulator pressure transients are simulated for constant steam charging and discharging flow rates, and the influence of the nonequilibrium condensation and evaporation rates on the steam accumulator capacity is shown. It is concluded that the commonly used equilibrium thermodynamic approach to the steam accumulator design does not provide accurate results in cases of rapid charging and discharging transients; therefore, there is a need for the application of the nonequilibrium approach.",
publisher = "Taylor & Francis Inc, Philadelphia",
journal = "Heat Transfer Engineering",
title = "Prediction and Control of Steam Accumulation",
pages = "510-498",
number = "5",
volume = "36",
doi = "10.1080/01457632.2014.935226"
}
Stevanović, V., Petrović, M. M., Milivojević, S.,& Maslovarić, B.. (2015). Prediction and Control of Steam Accumulation. in Heat Transfer Engineering
Taylor & Francis Inc, Philadelphia., 36(5), 498-510.
https://doi.org/10.1080/01457632.2014.935226
Stevanović V, Petrović MM, Milivojević S, Maslovarić B. Prediction and Control of Steam Accumulation. in Heat Transfer Engineering. 2015;36(5):498-510.
doi:10.1080/01457632.2014.935226 .
Stevanović, Vladimir, Petrović, Milan M., Milivojević, Sanja, Maslovarić, Blaženka, "Prediction and Control of Steam Accumulation" in Heat Transfer Engineering, 36, no. 5 (2015):498-510,
https://doi.org/10.1080/01457632.2014.935226 . .
23
6
26

Predviđanje dvofaznog strujanja sa generacijom pare oko cevi u snopu u isparivačima i generatorima pare

Maslovarić, Blaženka; Stevanović, Vladimir; Milivojević, Sanja; Petrović, Milan M.

(Beograd : Savez mašinskih i elektrotehničkih inženjera Srbije (SMEITS), 2014)

TY  - JOUR
AU  - Maslovarić, Blaženka
AU  - Stevanović, Vladimir
AU  - Milivojević, Sanja
AU  - Petrović, Milan M.
PY  - 2014
UR  - https://machinery.mas.bg.ac.rs/handle/123456789/4506
AB  - U hemijskoj industriji i energetici se koriste isparivači i 
generatori pare sa ključanjem na spoljašnjoj površini 
cevi koje formiraju cevni snop. Pri ključanju fluida
dešavaju se složeni procesi prenosa toplote i mase koji 
određuju polje brzina obe faze, polje pritiska i raspored zapreminskog
udela parne faze u ovim komponentama. Velike 
vrednosti zapreminskog udela pare mogu da izazovu krizu 
razmene toplote, koja se javlja u promenljivim ili prelaznim 
režimima kada je deo cevnog snopa okružen samo parnom 
fazom. Takođe, veliki protok dvofazne mešavine može da 
dovede do vibracija cevi isparivača ili generatora pare, dok 
recirkulacija tečnosti može da izazove taloženje primesa 
u pojedinim delovima generatora. Model predstavljen u 
ovom radu je podrška projektovanju i analizama rada generatora
pare i isparivača. Zasnovan je na rešavanju bilansnih
jednačina za svaku od faza u dvofaznom toku, uz primenu
odgovarajućih konstitutivnih korelacija i omogućava 
izračunavanje brzinskog polja, polja pritiska i zapreminskog
udela pare oko horizontalnog ili vertikalnog cevnog 
snopa, kao i predviđanje položaja dvofazne mešavine
PB  - Beograd : Savez mašinskih i elektrotehničkih inženjera Srbije (SMEITS)
T2  - Procesna tehnika
T1  - Predviđanje dvofaznog strujanja sa generacijom pare oko  cevi u snopu u isparivačima i generatorima pare
EP  - 55
IS  - 1
SP  - 48
VL  - 26
UR  - https://hdl.handle.net/21.15107/rcub_machinery_4506
ER  - 
@article{
author = "Maslovarić, Blaženka and Stevanović, Vladimir and Milivojević, Sanja and Petrović, Milan M.",
year = "2014",
abstract = "U hemijskoj industriji i energetici se koriste isparivači i 
generatori pare sa ključanjem na spoljašnjoj površini 
cevi koje formiraju cevni snop. Pri ključanju fluida
dešavaju se složeni procesi prenosa toplote i mase koji 
određuju polje brzina obe faze, polje pritiska i raspored zapreminskog
udela parne faze u ovim komponentama. Velike 
vrednosti zapreminskog udela pare mogu da izazovu krizu 
razmene toplote, koja se javlja u promenljivim ili prelaznim 
režimima kada je deo cevnog snopa okružen samo parnom 
fazom. Takođe, veliki protok dvofazne mešavine može da 
dovede do vibracija cevi isparivača ili generatora pare, dok 
recirkulacija tečnosti može da izazove taloženje primesa 
u pojedinim delovima generatora. Model predstavljen u 
ovom radu je podrška projektovanju i analizama rada generatora
pare i isparivača. Zasnovan je na rešavanju bilansnih
jednačina za svaku od faza u dvofaznom toku, uz primenu
odgovarajućih konstitutivnih korelacija i omogućava 
izračunavanje brzinskog polja, polja pritiska i zapreminskog
udela pare oko horizontalnog ili vertikalnog cevnog 
snopa, kao i predviđanje položaja dvofazne mešavine",
publisher = "Beograd : Savez mašinskih i elektrotehničkih inženjera Srbije (SMEITS)",
journal = "Procesna tehnika",
title = "Predviđanje dvofaznog strujanja sa generacijom pare oko  cevi u snopu u isparivačima i generatorima pare",
pages = "55-48",
number = "1",
volume = "26",
url = "https://hdl.handle.net/21.15107/rcub_machinery_4506"
}
Maslovarić, B., Stevanović, V., Milivojević, S.,& Petrović, M. M.. (2014). Predviđanje dvofaznog strujanja sa generacijom pare oko  cevi u snopu u isparivačima i generatorima pare. in Procesna tehnika
Beograd : Savez mašinskih i elektrotehničkih inženjera Srbije (SMEITS)., 26(1), 48-55.
https://hdl.handle.net/21.15107/rcub_machinery_4506
Maslovarić B, Stevanović V, Milivojević S, Petrović MM. Predviđanje dvofaznog strujanja sa generacijom pare oko  cevi u snopu u isparivačima i generatorima pare. in Procesna tehnika. 2014;26(1):48-55.
https://hdl.handle.net/21.15107/rcub_machinery_4506 .
Maslovarić, Blaženka, Stevanović, Vladimir, Milivojević, Sanja, Petrović, Milan M., "Predviđanje dvofaznog strujanja sa generacijom pare oko  cevi u snopu u isparivačima i generatorima pare" in Procesna tehnika, 26, no. 1 (2014):48-55,
https://hdl.handle.net/21.15107/rcub_machinery_4506 .