TY  - CONF
AU  - Karličić, Nikola
AU  - Radenković, Darko
AU  - Obradović, Marko
AU  - Todorović, Dušan
AU  - Jovović, Aleksandar
AU  - Radić, Dejan
PY  - 2023
UR  - https://machinery.mas.bg.ac.rs/handle/123456789/7080
AB  - U radu je prikazan numerički proračun pada pritiska pri pneumatskom transportu letećeg pepela  iz  termoelektrane.  Cilj  istraživanja  je  verifikacija  razvijenog  modela  upoređivanjem numeričkih rezultata sa merenjima pritiska duž cevovoda. Numerički model je razvijen na osnovu obimnih  eksperimentalnih istraživanja  sprovedenih  na  sistemu  pneumatskog  transporta  pepela kolubarskog  lignita,  velikog  kapaciteta  i  velike  dužine.  Ojler-Ojlerov  pristup  omogućava sveobuhvatno istraživanje složenih pojava pri pneumatskom transportu, uzimajući u obzir dvofaznu prirodu  sistema  i  pružajući  mogućnost  sagledavanja  ponašanje  čestica,  pada  pritiska  i  drugih ključnih parametara. Formiranje mreže za Ojler-Ojlerove  simulacije  u  OpenFOAM-u  predstavlja složen  proces,  što  uključuje  definisanje  računskog  domena,  generisanje  odgovarajuće  mrežne strukture i postavljanje odgovarajućih graničnih uslova i za gasnu i za čvrstu fazu. Potrebno je pažljivo  razmatranje  da  bi  se  što  vernije  predstavila  geometrija  i  definisali  svi  parametri  u pneumatskim transportnim sistemima. Ojler-Ojlerove numeričke simulacije pneumatskog transporta pepela  u  kosoj  cevi  su  sprovedene  u  OpenFOAM-u, koristeći paket twoPhaseEulerFoam  solver. Numerička mreža je formirana kao O-mreža za deonicu cevovoda dužine 90 m, prečnika 0,2604 m i nagiba od 1,885 °. Sve ćelije mreže su značajno veće od prečnika čestica pepela. Rezultati numeričkih simulacija  u  pogledu  pada  pritiska  se  veoma  dobro  slažu  sa  eksperimentalnim  rezultatima  za ispitivani slučaj. Iako je Ojler-Ojlerov model izutno složen u smislu definisanja graničnih  uslova, pokazao se kao pouzdan za za razmatrani slučaj, odnosno za razmatrane uslove.
AB  - This paper presents a numerical calculation of pressure drop in pneumatic conveying of fly ash from a thermal power plant. The objective of this research is to verify the developed model by com-paring  the  numerical  results  with  pressure  measurements  taken  along  the  pipeline.  The  numerical model is developed based on extensive experimental research conducted on a high-capacity and long-distance pneumatic conveying system for Kolubara lignite ash. The Euler-Euler approach enables a comprehensive investigation of the complex dynamics involved in pneumatic conveying, considering the two-phase nature of the system and providing valuable insights into the particle behavior, pres-sure drop, and other key parameters. Creating a mesh for Euler-Euler simulations in OpenFOAM can be a complex process. It involves defining the computational domain, generating a suitable mesh structure, and ensuring proper boundary conditions for both the gas and solid phases. Careful con-sideration is required to accurately represent the geometry and capture the relevant flow physics in pneumatic conveying systems. In this study, Euler-Euler numerical simulations of pneumatic convey-ing of ash in an inclined pipe are conducted in OpenFOAM, using twoPhaseEulerFoam solver. Nu-merical mesh is generated as an O-grid for a pipeline section with a length of 90 m, a diameter of 0.2604 m, and an inclination of 1.885 °. All mesh cells are significantly larger than the ash diameter.
PB  - Beograd : Savez mašinskih i elektrotehničkih inženjera i tehničara Srbije (SMEITS)
C3  - Zbornik Međunarodnog Kongresa O Procesnoj Industriji – Procesing 2023
T1  - Numeričke simulacije pneumatskog transporta letećeg pepela iz termoelektrane koristeći OpenFOAM
T1  - Numerical simulations of fly ash pneumatic conveying from a thermalpower plant using OpenFOAM
EP  - 292
IS  - 1
SP  - 291
VL  - 36
UR  - https://hdl.handle.net/21.15107/rcub_machinery_7080
ER  - 

@conference{
author = "Karličić, Nikola and Radenković, Darko and Obradović, Marko and Todorović, Dušan and Jovović, Aleksandar and Radić, Dejan",
year = "2023",
abstract = "U radu je prikazan numerički proračun pada pritiska pri pneumatskom transportu letećeg pepela  iz  termoelektrane.  Cilj  istraživanja  je  verifikacija  razvijenog  modela  upoređivanjem numeričkih rezultata sa merenjima pritiska duž cevovoda. Numerički model je razvijen na osnovu obimnih  eksperimentalnih istraživanja  sprovedenih  na  sistemu  pneumatskog  transporta  pepela kolubarskog  lignita,  velikog  kapaciteta  i  velike  dužine.  Ojler-Ojlerov  pristup  omogućava sveobuhvatno istraživanje složenih pojava pri pneumatskom transportu, uzimajući u obzir dvofaznu prirodu  sistema  i  pružajući  mogućnost  sagledavanja  ponašanje  čestica,  pada  pritiska  i  drugih ključnih parametara. Formiranje mreže za Ojler-Ojlerove  simulacije  u  OpenFOAM-u  predstavlja složen  proces,  što  uključuje  definisanje  računskog  domena,  generisanje  odgovarajuće  mrežne strukture i postavljanje odgovarajućih graničnih uslova i za gasnu i za čvrstu fazu. Potrebno je pažljivo  razmatranje  da  bi  se  što  vernije  predstavila  geometrija  i  definisali  svi  parametri  u pneumatskim transportnim sistemima. Ojler-Ojlerove numeričke simulacije pneumatskog transporta pepela  u  kosoj  cevi  su  sprovedene  u  OpenFOAM-u, koristeći paket twoPhaseEulerFoam  solver. Numerička mreža je formirana kao O-mreža za deonicu cevovoda dužine 90 m, prečnika 0,2604 m i nagiba od 1,885 °. Sve ćelije mreže su značajno veće od prečnika čestica pepela. Rezultati numeričkih simulacija  u  pogledu  pada  pritiska  se  veoma  dobro  slažu  sa  eksperimentalnim  rezultatima  za ispitivani slučaj. Iako je Ojler-Ojlerov model izutno složen u smislu definisanja graničnih  uslova, pokazao se kao pouzdan za za razmatrani slučaj, odnosno za razmatrane uslove., This paper presents a numerical calculation of pressure drop in pneumatic conveying of fly ash from a thermal power plant. The objective of this research is to verify the developed model by com-paring  the  numerical  results  with  pressure  measurements  taken  along  the  pipeline.  The  numerical model is developed based on extensive experimental research conducted on a high-capacity and long-distance pneumatic conveying system for Kolubara lignite ash. The Euler-Euler approach enables a comprehensive investigation of the complex dynamics involved in pneumatic conveying, considering the two-phase nature of the system and providing valuable insights into the particle behavior, pres-sure drop, and other key parameters. Creating a mesh for Euler-Euler simulations in OpenFOAM can be a complex process. It involves defining the computational domain, generating a suitable mesh structure, and ensuring proper boundary conditions for both the gas and solid phases. Careful con-sideration is required to accurately represent the geometry and capture the relevant flow physics in pneumatic conveying systems. In this study, Euler-Euler numerical simulations of pneumatic convey-ing of ash in an inclined pipe are conducted in OpenFOAM, using twoPhaseEulerFoam solver. Nu-merical mesh is generated as an O-grid for a pipeline section with a length of 90 m, a diameter of 0.2604 m, and an inclination of 1.885 °. All mesh cells are significantly larger than the ash diameter.",
publisher = "Beograd : Savez mašinskih i elektrotehničkih inženjera i tehničara Srbije (SMEITS)",
journal = "Zbornik Međunarodnog Kongresa O Procesnoj Industriji – Procesing 2023",
title = "Numeričke simulacije pneumatskog transporta letećeg pepela iz termoelektrane koristeći OpenFOAM, Numerical simulations of fly ash pneumatic conveying from a thermalpower plant using OpenFOAM",
pages = "292-291",
number = "1",
volume = "36",
url = "https://hdl.handle.net/21.15107/rcub_machinery_7080"
}

Karličić, N., Radenković, D., Obradović, M., Todorović, D., Jovović, A.,& Radić, D.. (2023). Numeričke simulacije pneumatskog transporta letećeg pepela iz termoelektrane koristeći OpenFOAM. in Zbornik Međunarodnog Kongresa O Procesnoj Industriji – Procesing 2023
Beograd : Savez mašinskih i elektrotehničkih inženjera i tehničara Srbije (SMEITS)., 36(1), 291-292.
https://hdl.handle.net/21.15107/rcub_machinery_7080

Karličić N, Radenković D, Obradović M, Todorović D, Jovović A, Radić D. Numeričke simulacije pneumatskog transporta letećeg pepela iz termoelektrane koristeći OpenFOAM. in Zbornik Međunarodnog Kongresa O Procesnoj Industriji – Procesing 2023. 2023;36(1):291-292.
https://hdl.handle.net/21.15107/rcub_machinery_7080 .

Karličić, Nikola, Radenković, Darko, Obradović, Marko, Todorović, Dušan, Jovović, Aleksandar, Radić, Dejan, "Numeričke simulacije pneumatskog transporta letećeg pepela iz termoelektrane koristeći OpenFOAM" in Zbornik Međunarodnog Kongresa O Procesnoj Industriji – Procesing 2023, 36, no. 1 (2023):291-292,
https://hdl.handle.net/21.15107/rcub_machinery_7080 .

TY  - JOUR
AU  - Raković, Milan
AU  - Radenković, Darko
AU  - Ćoćić, Aleksandar
AU  - Lečić, Milan
PY  - 2022
UR  - https://machinery.mas.bg.ac.rs/handle/123456789/3693
AB  - In this work, numerical simulations of upward turbulent bubbly flows in vertical pipes are conducted in the Euler-Euler framework with a low-Reynolds-number (LRN) model for liquid. It is found that the existing correlation for the drag coefficient of a single bubble in a shear flow, which has been successfully used along with the high-Reynolds-number (HRN) models, cannot be used with the LRN model. The reason is that drag forces of bubbles calculated using such correlation are enormous in near-wall cells (order of 10(12) N/m(3)), which causes a divergence of numerical simulations with LRN. Therefore, a modified correlation for the drag coefficient of a single bubble in shear flow, that can be used successfully with the LRN model, has been proposed. The results of numerical simulations, performed with a new correlation for the drag coefficient, are analysed and compared to selected experimental measurements for different pipe diameters and different flow conditions of gas and liquid. It is shown that the largest effect of the application of the new correlation for the drag coefficient of a single bubble in shear flow in numerical simulations can be achieved on the reduction of the relative velocity between gas and liquid. The degree of this reduction depends on the pipe diameter and liquid volumetric flux.
PB  - Sage Publications Ltd, London
T2  - Advances in Mechanical Engineering
T1  - Euler-Euler numerical simulations of upward turbulent bubbly flows in vertical pipes with low-Reynolds-number model
IS  - 4
VL  - 14
DO  - 10.1177/16878132221094909
ER  - 

@article{
author = "Raković, Milan and Radenković, Darko and Ćoćić, Aleksandar and Lečić, Milan",
year = "2022",
abstract = "In this work, numerical simulations of upward turbulent bubbly flows in vertical pipes are conducted in the Euler-Euler framework with a low-Reynolds-number (LRN) model for liquid. It is found that the existing correlation for the drag coefficient of a single bubble in a shear flow, which has been successfully used along with the high-Reynolds-number (HRN) models, cannot be used with the LRN model. The reason is that drag forces of bubbles calculated using such correlation are enormous in near-wall cells (order of 10(12) N/m(3)), which causes a divergence of numerical simulations with LRN. Therefore, a modified correlation for the drag coefficient of a single bubble in shear flow, that can be used successfully with the LRN model, has been proposed. The results of numerical simulations, performed with a new correlation for the drag coefficient, are analysed and compared to selected experimental measurements for different pipe diameters and different flow conditions of gas and liquid. It is shown that the largest effect of the application of the new correlation for the drag coefficient of a single bubble in shear flow in numerical simulations can be achieved on the reduction of the relative velocity between gas and liquid. The degree of this reduction depends on the pipe diameter and liquid volumetric flux.",
publisher = "Sage Publications Ltd, London",
journal = "Advances in Mechanical Engineering",
title = "Euler-Euler numerical simulations of upward turbulent bubbly flows in vertical pipes with low-Reynolds-number model",
number = "4",
volume = "14",
doi = "10.1177/16878132221094909"
}

Raković, M., Radenković, D., Ćoćić, A.,& Lečić, M.. (2022). Euler-Euler numerical simulations of upward turbulent bubbly flows in vertical pipes with low-Reynolds-number model. in Advances in Mechanical Engineering
Sage Publications Ltd, London., 14(4).
https://doi.org/10.1177/16878132221094909

Raković M, Radenković D, Ćoćić A, Lečić M. Euler-Euler numerical simulations of upward turbulent bubbly flows in vertical pipes with low-Reynolds-number model. in Advances in Mechanical Engineering. 2022;14(4).
doi:10.1177/16878132221094909 .

Raković, Milan, Radenković, Darko, Ćoćić, Aleksandar, Lečić, Milan, "Euler-Euler numerical simulations of upward turbulent bubbly flows in vertical pipes with low-Reynolds-number model" in Advances in Mechanical Engineering, 14, no. 4 (2022),
https://doi.org/10.1177/16878132221094909 . .

TY  - CONF
AU  - Raković, Milan
AU  - Radenković, Darko
AU  - Ćoćić, Aleksandar
AU  - Lečić, Milan
PY  - 2022
UR  - https://machinery.mas.bg.ac.rs/handle/123456789/6219
AB  - Numerical simulations of upward turbulent bubbly flows in vertical pipes are carried
out in the Euler-Euler framework with a low-Reynolds-number (LRN) model for liquid for
various flow conditions. It is found that the correlation for the drag coefficient of a single
bubble in a shear flow, which has been successfully used in numerical simulations with
the high-Reynolds-number (HRN) models, cannot be used with the LRN model. The
reason is an excessive value of drag coefficient of a single bubble in the near-wall cells.
Therefore, a new correlation for the drag coefficient of a single bubble in shear flow has
been proposed. The results of numerical simulations are analysed and compared to
selected experiment results. It is shown that the largest effect of the application of the
new correlation for the drag coefficient of a single bubble in shear flow can be achieved
on the reduction of the relative velocity between gas and liquid. Overall, the results of
numerical simulations agree well with the experimental results.
C3  - ICAS 2022 Book of abstracts
T1  - Influence of the drag coefficient of a single bubble in vertical upward turbulent bubbly flows
SP  - 85
UR  - https://hdl.handle.net/21.15107/rcub_machinery_6219
ER  - 

@conference{
author = "Raković, Milan and Radenković, Darko and Ćoćić, Aleksandar and Lečić, Milan",
year = "2022",
abstract = "Numerical simulations of upward turbulent bubbly flows in vertical pipes are carried
out in the Euler-Euler framework with a low-Reynolds-number (LRN) model for liquid for
various flow conditions. It is found that the correlation for the drag coefficient of a single
bubble in a shear flow, which has been successfully used in numerical simulations with
the high-Reynolds-number (HRN) models, cannot be used with the LRN model. The
reason is an excessive value of drag coefficient of a single bubble in the near-wall cells.
Therefore, a new correlation for the drag coefficient of a single bubble in shear flow has
been proposed. The results of numerical simulations are analysed and compared to
selected experiment results. It is shown that the largest effect of the application of the
new correlation for the drag coefficient of a single bubble in shear flow can be achieved
on the reduction of the relative velocity between gas and liquid. Overall, the results of
numerical simulations agree well with the experimental results.",
journal = "ICAS 2022 Book of abstracts",
title = "Influence of the drag coefficient of a single bubble in vertical upward turbulent bubbly flows",
pages = "85",
url = "https://hdl.handle.net/21.15107/rcub_machinery_6219"
}

Raković, M., Radenković, D., Ćoćić, A.,& Lečić, M.. (2022). Influence of the drag coefficient of a single bubble in vertical upward turbulent bubbly flows. in ICAS 2022 Book of abstracts, 85.
https://hdl.handle.net/21.15107/rcub_machinery_6219

Raković M, Radenković D, Ćoćić A, Lečić M. Influence of the drag coefficient of a single bubble in vertical upward turbulent bubbly flows. in ICAS 2022 Book of abstracts. 2022;:85.
https://hdl.handle.net/21.15107/rcub_machinery_6219 .

Raković, Milan, Radenković, Darko, Ćoćić, Aleksandar, Lečić, Milan, "Influence of the drag coefficient of a single bubble in vertical upward turbulent bubbly flows" in ICAS 2022 Book of abstracts (2022):85,
https://hdl.handle.net/21.15107/rcub_machinery_6219 .

TY  - JOUR
AU  - Radenković, Darko
AU  - Simonin, Olivier
PY  - 2021
UR  - https://machinery.mas.bg.ac.rs/handle/123456789/3489
AB  - In gas-solid confined flows, particle rebound on a rough wall may have a great influence on the macroscopic properties of both phases. Existing simulation methods use simplified approaches where surface roughness is modelled as two-dimensional or isotropic. To improve the accuracy of such simulations, an anisotropic virtual rough wall statistical approach and the corresponding Lagrangian stochastic particle-wall collision model are proposed. From deterministic simulations of the impact of particles on the anisotropic virtual wall given as correlated bi-Gaussian surface, wall-normal vector angle statistics are used for model development. Rebound angle statistics computed from deterministic simulations and using the proposed stochastic model are in very good agreement. Incident particles in vertical planes not collinear with one of the principal directions of the anisotropic rough surface are bouncing with a mean transverse angle towards the principal direction of lower roughness.
PB  - Elsevier, Amsterdam
T2  - Powder Technology
T1  - Modelling of three-dimensional particle rebound from an anisotropic rough wall
EP  - 183
SP  - 165
VL  - 393
DO  - 10.1016/j.powtec.2021.07.055
ER  - 

@article{
author = "Radenković, Darko and Simonin, Olivier",
year = "2021",
abstract = "In gas-solid confined flows, particle rebound on a rough wall may have a great influence on the macroscopic properties of both phases. Existing simulation methods use simplified approaches where surface roughness is modelled as two-dimensional or isotropic. To improve the accuracy of such simulations, an anisotropic virtual rough wall statistical approach and the corresponding Lagrangian stochastic particle-wall collision model are proposed. From deterministic simulations of the impact of particles on the anisotropic virtual wall given as correlated bi-Gaussian surface, wall-normal vector angle statistics are used for model development. Rebound angle statistics computed from deterministic simulations and using the proposed stochastic model are in very good agreement. Incident particles in vertical planes not collinear with one of the principal directions of the anisotropic rough surface are bouncing with a mean transverse angle towards the principal direction of lower roughness.",
publisher = "Elsevier, Amsterdam",
journal = "Powder Technology",
title = "Modelling of three-dimensional particle rebound from an anisotropic rough wall",
pages = "183-165",
volume = "393",
doi = "10.1016/j.powtec.2021.07.055"
}

Radenković, D.,& Simonin, O.. (2021). Modelling of three-dimensional particle rebound from an anisotropic rough wall. in Powder Technology
Elsevier, Amsterdam., 393, 165-183.
https://doi.org/10.1016/j.powtec.2021.07.055

Radenković D, Simonin O. Modelling of three-dimensional particle rebound from an anisotropic rough wall. in Powder Technology. 2021;393:165-183.
doi:10.1016/j.powtec.2021.07.055 .

Radenković, Darko, Simonin, Olivier, "Modelling of three-dimensional particle rebound from an anisotropic rough wall" in Powder Technology, 393 (2021):165-183,
https://doi.org/10.1016/j.powtec.2021.07.055 . .

TY  - THES
AU  - Radenković, Darko
PY  - 2019
UR  - http://eteze.bg.ac.rs/application/showtheses?thesesId=6900
UR  - https://nardus.mpn.gov.rs/handle/123456789/11471
UR  - https://fedorabg.bg.ac.rs/fedora/get/o:20226/bdef:Content/download
UR  - http://vbs.rs/scripts/cobiss?command=DISPLAY&base=70036&RID=51649551
UR  - https://machinery.mas.bg.ac.rs/handle/123456789/67
AB  - U disertaciji se proučava uticaj hrapavosti zidova pri strujanju mešavine če- stica i gasa. Pri ovakvim strujanjima, sudar čestica sa hrapavim zidom je uvek trodimenzionalan (3D) usled prilaznih uglova čestica prema zidu kao i geomet- rije hrapavih zidova, dok su prema ranijim istraživanjima, modeli korišćeni za ovaj sudar u numeričkim simulacijama uglavnom dvodimenzionalan (2D) ili uprošćeni 3D. Kako bi se omogućio tačniji proračun strujanja mešavine čestica i gasa, cilj disertacije je razvoj modela za 3D sudar čestice i hrapavog zida. U di- sertaciji su analizirani sudari čestica sa izotropnim i anizotropnim hrapavim zidovima, putem determinističkih simulacija i izvedeni su odgovarajući stoha- stički modeli za te sudare, primenljivi u Ojler-Lagranž simulacijama strujanja mešavine čestica i gasa. Nalazi se da sa porastom prilaznog ugla čestica u od- nosu na makroskopski gladak zid, dolazi do porasta standardne devijacije bočnih uglova odbijanja čestica i u slučaju izotropne i anizotropne površine. Mehani- zam višestrukih sudara čestica sa zidom ostaje nepromenjen u odnosu na 2D model za sudar čestice i zida. Izvedeni stohastički modeli se porede se raspoloživim eksperimentalnim rezultatima i determinističkim simulacijama. Izvršene su LES simulacije strujanja čistog fluida (bez prisustva disperzne faze) u horizon- talnom kanalu pravougaonog poprečnog preseka koristeći različite SGS modele: model Smagorinskog, WALE i dinamički jedno-jednačinski model. Simulacije su izvedene u programskom paketu OpenFOAM. Uticaj zidova tog kanala, različite hrapavosti, na disperznu fazu, pri strujanju mešavine gasa i čestica istražen je putem LES-DPS simulacija. Međusobni sudari čestica se izračunavaju prime- nom modela mekih sfera. Kada se ovi sudari zanemare, što bi bilo opravdano pri strujanjima sa veoma malom koncentracijom disperzne faze, nalazi se da hra- pavost zida može biti značajan mehanizam za produkciju poprečnih fluktuacije čestica. Uzimanjem u obzir međusobnih sudara čestica, dolazi do porasta popreč- nih fluktuacija brzine čestica i pokazuje se da je u pogledu ovih fluktuacija uticaj međusobnog sudara čestica veći u odnosu na uticaj hrapavosti zidova ka- nala.
AB  - Influence of wall roughness in turbulent particle-laden wall confined flows is studied in this thesis. In such a flow configuration, particle-wall collision is always three-dimensional (3D) owing to the particle incident angles and rough wall geometry, while according to the previous investigations, models for this collision in numerical simulations are mostly two-dimensional (2D) or simplified 3D. In order to enable more accurate calculation of wall confined particle-laden flows, the goal of the thesis is development of the model for 3D particle-rough wall collision. Particles collision with isotropic and anisotropic rough walls are analyzed using deterministic simulations and stochastic models for those collisions are developed in Euler-Lagrangian framework. It is found that with increase of particle incident angle a standard deviation of particle transverse angles increases, for cases of isotropic and anisotropic rough wall surface. Mechanism of multiple particlerough wall collision remains unchanged comparing to the 2D model for particle-rough wall collision. Derived stochastic models are compared to the available experimental measurements and results of deterministic simulations. LES of pure fluid flow (without disperse phase) in a horizontal channel are carried out, using different SGS models: Smagorinsky, WALE and dynamic one-equation model. Simulations are carried out in software package OpenFOAM. Also, LES-DPS is performed in turbulent particleladen flow in horizontal channel in order to estimate influence of walls roughness on disperse phase. Inter-particle collisions are calculated using soft-sphere model. When these collisions are neglected, which is justified at very diluted flows, it is shown that wall roughness can be significant mechanism for production of particle spanwise velocity fluctuations. When inter-particle collisions are accounted for, these fluctuations increase and the influence of inter-particle collisions on particle spanwise velocity fluctuations becomes larger than the influence of channel wall roughness.
PB  - Univerzitet u Beogradu, Mašinski fakultet
T1  - Uticaj hrapavosti zidova kanala pri strujanju mešavine gasa i čestica u unutrašnjim turbulentnim strujanjima
T1  - Influence of wall roughness in particle-laden turbulent channel flows
UR  - https://hdl.handle.net/21.15107/rcub_nardus_11471
ER  - 

@phdthesis{
author = "Radenković, Darko",
year = "2019",
abstract = "U disertaciji se proučava uticaj hrapavosti zidova pri strujanju mešavine če- stica i gasa. Pri ovakvim strujanjima, sudar čestica sa hrapavim zidom je uvek trodimenzionalan (3D) usled prilaznih uglova čestica prema zidu kao i geomet- rije hrapavih zidova, dok su prema ranijim istraživanjima, modeli korišćeni za ovaj sudar u numeričkim simulacijama uglavnom dvodimenzionalan (2D) ili uprošćeni 3D. Kako bi se omogućio tačniji proračun strujanja mešavine čestica i gasa, cilj disertacije je razvoj modela za 3D sudar čestice i hrapavog zida. U di- sertaciji su analizirani sudari čestica sa izotropnim i anizotropnim hrapavim zidovima, putem determinističkih simulacija i izvedeni su odgovarajući stoha- stički modeli za te sudare, primenljivi u Ojler-Lagranž simulacijama strujanja mešavine čestica i gasa. Nalazi se da sa porastom prilaznog ugla čestica u od- nosu na makroskopski gladak zid, dolazi do porasta standardne devijacije bočnih uglova odbijanja čestica i u slučaju izotropne i anizotropne površine. Mehani- zam višestrukih sudara čestica sa zidom ostaje nepromenjen u odnosu na 2D model za sudar čestice i zida. Izvedeni stohastički modeli se porede se raspoloživim eksperimentalnim rezultatima i determinističkim simulacijama. Izvršene su LES simulacije strujanja čistog fluida (bez prisustva disperzne faze) u horizon- talnom kanalu pravougaonog poprečnog preseka koristeći različite SGS modele: model Smagorinskog, WALE i dinamički jedno-jednačinski model. Simulacije su izvedene u programskom paketu OpenFOAM. Uticaj zidova tog kanala, različite hrapavosti, na disperznu fazu, pri strujanju mešavine gasa i čestica istražen je putem LES-DPS simulacija. Međusobni sudari čestica se izračunavaju prime- nom modela mekih sfera. Kada se ovi sudari zanemare, što bi bilo opravdano pri strujanjima sa veoma malom koncentracijom disperzne faze, nalazi se da hra- pavost zida može biti značajan mehanizam za produkciju poprečnih fluktuacije čestica. Uzimanjem u obzir međusobnih sudara čestica, dolazi do porasta popreč- nih fluktuacija brzine čestica i pokazuje se da je u pogledu ovih fluktuacija uticaj međusobnog sudara čestica veći u odnosu na uticaj hrapavosti zidova ka- nala., Influence of wall roughness in turbulent particle-laden wall confined flows is studied in this thesis. In such a flow configuration, particle-wall collision is always three-dimensional (3D) owing to the particle incident angles and rough wall geometry, while according to the previous investigations, models for this collision in numerical simulations are mostly two-dimensional (2D) or simplified 3D. In order to enable more accurate calculation of wall confined particle-laden flows, the goal of the thesis is development of the model for 3D particle-rough wall collision. Particles collision with isotropic and anisotropic rough walls are analyzed using deterministic simulations and stochastic models for those collisions are developed in Euler-Lagrangian framework. It is found that with increase of particle incident angle a standard deviation of particle transverse angles increases, for cases of isotropic and anisotropic rough wall surface. Mechanism of multiple particlerough wall collision remains unchanged comparing to the 2D model for particle-rough wall collision. Derived stochastic models are compared to the available experimental measurements and results of deterministic simulations. LES of pure fluid flow (without disperse phase) in a horizontal channel are carried out, using different SGS models: Smagorinsky, WALE and dynamic one-equation model. Simulations are carried out in software package OpenFOAM. Also, LES-DPS is performed in turbulent particleladen flow in horizontal channel in order to estimate influence of walls roughness on disperse phase. Inter-particle collisions are calculated using soft-sphere model. When these collisions are neglected, which is justified at very diluted flows, it is shown that wall roughness can be significant mechanism for production of particle spanwise velocity fluctuations. When inter-particle collisions are accounted for, these fluctuations increase and the influence of inter-particle collisions on particle spanwise velocity fluctuations becomes larger than the influence of channel wall roughness.",
publisher = "Univerzitet u Beogradu, Mašinski fakultet",
title = "Uticaj hrapavosti zidova kanala pri strujanju mešavine gasa i čestica u unutrašnjim turbulentnim strujanjima, Influence of wall roughness in particle-laden turbulent channel flows",
url = "https://hdl.handle.net/21.15107/rcub_nardus_11471"
}

Radenković, D.. (2019). Uticaj hrapavosti zidova kanala pri strujanju mešavine gasa i čestica u unutrašnjim turbulentnim strujanjima. 
Univerzitet u Beogradu, Mašinski fakultet..
https://hdl.handle.net/21.15107/rcub_nardus_11471

Radenković D. Uticaj hrapavosti zidova kanala pri strujanju mešavine gasa i čestica u unutrašnjim turbulentnim strujanjima. 2019;.
https://hdl.handle.net/21.15107/rcub_nardus_11471 .

Radenković, Darko, "Uticaj hrapavosti zidova kanala pri strujanju mešavine gasa i čestica u unutrašnjim turbulentnim strujanjima" (2019),
https://hdl.handle.net/21.15107/rcub_nardus_11471 .

TY  - CONF
AU  - Radenković, Darko
AU  - Fede, Pascal
AU  - Simonin, Olivier
AU  - Crnojevic, Cvetko
PY  - 2019
UR  - https://machinery.mas.bg.ac.rs/handle/123456789/6672
C3  - 10th International Conference of Multiphase Flow
T1  - Large Eddy Simulation of particle laden  turbulent channel flows with isotropic or non-isotropic wall roughness
UR  - https://hdl.handle.net/21.15107/rcub_machinery_6672
ER  - 

@conference{
author = "Radenković, Darko and Fede, Pascal and Simonin, Olivier and Crnojevic, Cvetko",
year = "2019",
journal = "10th International Conference of Multiphase Flow",
title = "Large Eddy Simulation of particle laden  turbulent channel flows with isotropic or non-isotropic wall roughness",
url = "https://hdl.handle.net/21.15107/rcub_machinery_6672"
}

Radenković, D., Fede, P., Simonin, O.,& Crnojevic, C.. (2019). Large Eddy Simulation of particle laden  turbulent channel flows with isotropic or non-isotropic wall roughness. in 10th International Conference of Multiphase Flow.
https://hdl.handle.net/21.15107/rcub_machinery_6672

Radenković D, Fede P, Simonin O, Crnojevic C. Large Eddy Simulation of particle laden  turbulent channel flows with isotropic or non-isotropic wall roughness. in 10th International Conference of Multiphase Flow. 2019;.
https://hdl.handle.net/21.15107/rcub_machinery_6672 .

Radenković, Darko, Fede, Pascal, Simonin, Olivier, Crnojevic, Cvetko, "Large Eddy Simulation of particle laden  turbulent channel flows with isotropic or non-isotropic wall roughness" in 10th International Conference of Multiphase Flow (2019),
https://hdl.handle.net/21.15107/rcub_machinery_6672 .

TY  - CONF
AU  - Radenković, Darko
AU  - Simonin, Olivier
AU  - Crnojevic, Cvetko
PY  - 2018
UR  - https://machinery.mas.bg.ac.rs/handle/123456789/6673
T1  - Transverse particle dispersion induced by three dimensional rebound from isotropic or anisotropic rough wal
UR  - https://hdl.handle.net/21.15107/rcub_machinery_6673
ER  - 

@conference{
author = "Radenković, Darko and Simonin, Olivier and Crnojevic, Cvetko",
year = "2018",
title = "Transverse particle dispersion induced by three dimensional rebound from isotropic or anisotropic rough wal",
url = "https://hdl.handle.net/21.15107/rcub_machinery_6673"
}

Radenković, D., Simonin, O.,& Crnojevic, C.. (2018). Transverse particle dispersion induced by three dimensional rebound from isotropic or anisotropic rough wal. .
https://hdl.handle.net/21.15107/rcub_machinery_6673

Radenković D, Simonin O, Crnojevic C. Transverse particle dispersion induced by three dimensional rebound from isotropic or anisotropic rough wal. 2018;.
https://hdl.handle.net/21.15107/rcub_machinery_6673 .

Radenković, Darko, Simonin, Olivier, Crnojevic, Cvetko, "Transverse particle dispersion induced by three dimensional rebound from isotropic or anisotropic rough wal" (2018),
https://hdl.handle.net/21.15107/rcub_machinery_6673 .

TY  - JOUR
AU  - Petrović, Andrija
AU  - Svorcan, Jelena
AU  - Pejčev, Aleksandar
AU  - Radenković, Darko
AU  - Petrović, Aleksandar
PY  - 2018
UR  - https://machinery.mas.bg.ac.rs/handle/123456789/2930
AB  - Different applications of a variable area convergent-divergent nozzle are found in various parts of the industry. This paper presents the development of a new design methodology for a variable area convergent-divergent nozzle, to maintain constant nozzle area ratio for different values of mass flow rates. The validation of the presented model was carried out on an example supersonic ejector using experimental, numerical and analytical data. Analytical (one dimensional) and computational fluid dynamics models showed satisfactory prediction performance in comparison with the experiment. The average entrainment ratio error was between 10% and 7%, respectively. Results confirmed that the velocity of the primary fluid at the nozzle outlet is in accordance with the one dimensional analysis. Although disturbances (strong and weak shock waves) are visible, their effects are negligible. Also, supersonic ejector performances are presented through relations between entrainment ratio, outlet pressure and spindle position. Disadvantages of variable area nozzle utilization in ejector applications are emphasized.
PB  - Elsevier Science Inc, New York
T2  - Applied Mathematical Modelling
T1  - Comparison of novel variable area convergent-divergent nozzle performances obtained by analytic, computational and experimental methods
EP  - 225
SP  - 206
VL  - 57
DO  - 10.1016/j.apm.2018.01.016
ER  - 

@article{
author = "Petrović, Andrija and Svorcan, Jelena and Pejčev, Aleksandar and Radenković, Darko and Petrović, Aleksandar",
year = "2018",
abstract = "Different applications of a variable area convergent-divergent nozzle are found in various parts of the industry. This paper presents the development of a new design methodology for a variable area convergent-divergent nozzle, to maintain constant nozzle area ratio for different values of mass flow rates. The validation of the presented model was carried out on an example supersonic ejector using experimental, numerical and analytical data. Analytical (one dimensional) and computational fluid dynamics models showed satisfactory prediction performance in comparison with the experiment. The average entrainment ratio error was between 10% and 7%, respectively. Results confirmed that the velocity of the primary fluid at the nozzle outlet is in accordance with the one dimensional analysis. Although disturbances (strong and weak shock waves) are visible, their effects are negligible. Also, supersonic ejector performances are presented through relations between entrainment ratio, outlet pressure and spindle position. Disadvantages of variable area nozzle utilization in ejector applications are emphasized.",
publisher = "Elsevier Science Inc, New York",
journal = "Applied Mathematical Modelling",
title = "Comparison of novel variable area convergent-divergent nozzle performances obtained by analytic, computational and experimental methods",
pages = "225-206",
volume = "57",
doi = "10.1016/j.apm.2018.01.016"
}

Petrović, A., Svorcan, J., Pejčev, A., Radenković, D.,& Petrović, A.. (2018). Comparison of novel variable area convergent-divergent nozzle performances obtained by analytic, computational and experimental methods. in Applied Mathematical Modelling
Elsevier Science Inc, New York., 57, 206-225.
https://doi.org/10.1016/j.apm.2018.01.016

Petrović A, Svorcan J, Pejčev A, Radenković D, Petrović A. Comparison of novel variable area convergent-divergent nozzle performances obtained by analytic, computational and experimental methods. in Applied Mathematical Modelling. 2018;57:206-225.
doi:10.1016/j.apm.2018.01.016 .

Petrović, Andrija, Svorcan, Jelena, Pejčev, Aleksandar, Radenković, Darko, Petrović, Aleksandar, "Comparison of novel variable area convergent-divergent nozzle performances obtained by analytic, computational and experimental methods" in Applied Mathematical Modelling, 57 (2018):206-225,
https://doi.org/10.1016/j.apm.2018.01.016 . .

TY  - JOUR
AU  - Radenković, Darko
AU  - Simonin, Olivier
PY  - 2018
UR  - https://machinery.mas.bg.ac.rs/handle/123456789/2900
AB  - This paper describes an extension of the two-dimensional approach to particle-rough wall collision modelling (Sommerfeld and Huber, 1999; Konan et al., 2009) to the case of three-dimensional particle rebound from an isotropic rough wall surface. The virtual three-dimensional rough wall is represented as a Gaussian correlated surface. Normal vector angle statistical distributions are investigated in detail for such virtual rough walls, and a statistical modelling approach for these angles is proposed and validated in the frame of the low roughness approximation. Next, deterministic simulations of fully elastic particle collisions with the three-dimensional virtual wall roughness structure are carried out for various particle incident angles. It is shown that the rebound angle, in the bouncing plane of the particle, obeys the distribution given by the two-dimensional modelling approach. However, the three-dimensional structure induces a transverse deviation bouncing angle that obeys a Gaussian distribution with a standard deviation that increases with increase in incident angle. A statistical modelling approach for the virtual wall normal vector seen by any particle for a given incident angle is proposed and validated from deterministic simulation results. The probability that particles make only one rebound is in agreement with the two-dimensional multiple-collision model assumption. A new stochastic procedure for particle-isotropic rough wall interactions in a Lagrangian framework is developed and verified by comparisons with deterministic simulations and available experimental results.
PB  - Pergamon-Elsevier Science Ltd, Oxford
T2  - International Journal of Multiphase Flow
T1  - Stochastic modelling of three-dimensional particle rebound from isotropic rough wall surface
EP  - 50
SP  - 35
VL  - 109
DO  - 10.1016/j.ijmultiphaseflow.2018.07.013
ER  - 

@article{
author = "Radenković, Darko and Simonin, Olivier",
year = "2018",
abstract = "This paper describes an extension of the two-dimensional approach to particle-rough wall collision modelling (Sommerfeld and Huber, 1999; Konan et al., 2009) to the case of three-dimensional particle rebound from an isotropic rough wall surface. The virtual three-dimensional rough wall is represented as a Gaussian correlated surface. Normal vector angle statistical distributions are investigated in detail for such virtual rough walls, and a statistical modelling approach for these angles is proposed and validated in the frame of the low roughness approximation. Next, deterministic simulations of fully elastic particle collisions with the three-dimensional virtual wall roughness structure are carried out for various particle incident angles. It is shown that the rebound angle, in the bouncing plane of the particle, obeys the distribution given by the two-dimensional modelling approach. However, the three-dimensional structure induces a transverse deviation bouncing angle that obeys a Gaussian distribution with a standard deviation that increases with increase in incident angle. A statistical modelling approach for the virtual wall normal vector seen by any particle for a given incident angle is proposed and validated from deterministic simulation results. The probability that particles make only one rebound is in agreement with the two-dimensional multiple-collision model assumption. A new stochastic procedure for particle-isotropic rough wall interactions in a Lagrangian framework is developed and verified by comparisons with deterministic simulations and available experimental results.",
publisher = "Pergamon-Elsevier Science Ltd, Oxford",
journal = "International Journal of Multiphase Flow",
title = "Stochastic modelling of three-dimensional particle rebound from isotropic rough wall surface",
pages = "50-35",
volume = "109",
doi = "10.1016/j.ijmultiphaseflow.2018.07.013"
}

Radenković, D.,& Simonin, O.. (2018). Stochastic modelling of three-dimensional particle rebound from isotropic rough wall surface. in International Journal of Multiphase Flow
Pergamon-Elsevier Science Ltd, Oxford., 109, 35-50.
https://doi.org/10.1016/j.ijmultiphaseflow.2018.07.013

Radenković D, Simonin O. Stochastic modelling of three-dimensional particle rebound from isotropic rough wall surface. in International Journal of Multiphase Flow. 2018;109:35-50.
doi:10.1016/j.ijmultiphaseflow.2018.07.013 .

Radenković, Darko, Simonin, Olivier, "Stochastic modelling of three-dimensional particle rebound from isotropic rough wall surface" in International Journal of Multiphase Flow, 109 (2018):35-50,
https://doi.org/10.1016/j.ijmultiphaseflow.2018.07.013 . .

TY  - JOUR
AU  - Radenković, Darko
AU  - Milićev, Snežana
AU  - Stevanović, Nevena
PY  - 2016
UR  - https://machinery.mas.bg.ac.rs/handle/123456789/2368
AB  - U radu se proučava osnosimetrično, izotermsko, stišljivo strujanje gasa sa klizanjem, pri malim vrednostima Rejnoldsovog broja. Problem je rešen primenom jednačine kontinuiteta i Navije-Stoksovih jednačina, zajedno sa Maksvelovim graničnim uslovom prvog reda. Analitički rezultati su dobijeni primenom perturbacione metode. Dobijena rešenja se dobro slažu sa poznatim eksperimentalnim rezultatima drugih autora.
AB  - Low Reynolds number, axisymmetric, isothermal, compressible, slip gas flow in microtubes is investigated in this paper. The problem is solved by the continuum equations, continuity and Navier-Stokes, along with Maxwell first order boundary condition. The analytical results are obtained by perturbation method. The solutions show a good agreement with experimental results.
PB  - Univerzitet u Beogradu - Mašinski fakultet, Beograd
T2  - FME Transactions
T1  - Strujanje razređenog gasa u mikrocevima pri malim Rejnoldsovim brojevima
T1  - Rarefied gas flow in microtubes at low Reynolds numbers
EP  - 15
IS  - 1
SP  - 10
VL  - 44
DO  - 10.5937/fmet1601010R
ER  - 

@article{
author = "Radenković, Darko and Milićev, Snežana and Stevanović, Nevena",
year = "2016",
abstract = "U radu se proučava osnosimetrično, izotermsko, stišljivo strujanje gasa sa klizanjem, pri malim vrednostima Rejnoldsovog broja. Problem je rešen primenom jednačine kontinuiteta i Navije-Stoksovih jednačina, zajedno sa Maksvelovim graničnim uslovom prvog reda. Analitički rezultati su dobijeni primenom perturbacione metode. Dobijena rešenja se dobro slažu sa poznatim eksperimentalnim rezultatima drugih autora., Low Reynolds number, axisymmetric, isothermal, compressible, slip gas flow in microtubes is investigated in this paper. The problem is solved by the continuum equations, continuity and Navier-Stokes, along with Maxwell first order boundary condition. The analytical results are obtained by perturbation method. The solutions show a good agreement with experimental results.",
publisher = "Univerzitet u Beogradu - Mašinski fakultet, Beograd",
journal = "FME Transactions",
title = "Strujanje razređenog gasa u mikrocevima pri malim Rejnoldsovim brojevima, Rarefied gas flow in microtubes at low Reynolds numbers",
pages = "15-10",
number = "1",
volume = "44",
doi = "10.5937/fmet1601010R"
}

Radenković, D., Milićev, S.,& Stevanović, N.. (2016). Strujanje razređenog gasa u mikrocevima pri malim Rejnoldsovim brojevima. in FME Transactions
Univerzitet u Beogradu - Mašinski fakultet, Beograd., 44(1), 10-15.
https://doi.org/10.5937/fmet1601010R

Radenković D, Milićev S, Stevanović N. Strujanje razređenog gasa u mikrocevima pri malim Rejnoldsovim brojevima. in FME Transactions. 2016;44(1):10-15.
doi:10.5937/fmet1601010R .

Radenković, Darko, Milićev, Snežana, Stevanović, Nevena, "Strujanje razređenog gasa u mikrocevima pri malim Rejnoldsovim brojevima" in FME Transactions, 44, no. 1 (2016):10-15,
https://doi.org/10.5937/fmet1601010R . .

TY  - CHAP
AU  - Novković, Đorđe 
AU  - Lečić, Milan
AU  - Burazer, Jela
AU  - Radenković, Darko
PY  - 2015
UR  - https://machinery.mas.bg.ac.rs/handle/123456789/5587
PB  - University of Belgrade, Faculty of Mechanical Engineering, Belgrade, Serbia
T2  - Turbulence workshop - International symposium, University of Belgrade, Faculty of Mechanical Engineering, Book of Abstracts, Belgrade
T1  - Numerical flow simulation in the Agnew micro hydro turbine
UR  - https://hdl.handle.net/21.15107/rcub_machinery_5587
ER  - 

@inbook{
author = "Novković, Đorđe  and Lečić, Milan and Burazer, Jela and Radenković, Darko",
year = "2015",
publisher = "University of Belgrade, Faculty of Mechanical Engineering, Belgrade, Serbia",
journal = "Turbulence workshop - International symposium, University of Belgrade, Faculty of Mechanical Engineering, Book of Abstracts, Belgrade",
booktitle = "Numerical flow simulation in the Agnew micro hydro turbine",
url = "https://hdl.handle.net/21.15107/rcub_machinery_5587"
}

Novković, Đ., Lečić, M., Burazer, J.,& Radenković, D.. (2015). Numerical flow simulation in the Agnew micro hydro turbine. in Turbulence workshop - International symposium, University of Belgrade, Faculty of Mechanical Engineering, Book of Abstracts, Belgrade
University of Belgrade, Faculty of Mechanical Engineering, Belgrade, Serbia..
https://hdl.handle.net/21.15107/rcub_machinery_5587

Novković Đ, Lečić M, Burazer J, Radenković D. Numerical flow simulation in the Agnew micro hydro turbine. in Turbulence workshop - International symposium, University of Belgrade, Faculty of Mechanical Engineering, Book of Abstracts, Belgrade. 2015;.
https://hdl.handle.net/21.15107/rcub_machinery_5587 .

Novković, Đorđe , Lečić, Milan, Burazer, Jela, Radenković, Darko, "Numerical flow simulation in the Agnew micro hydro turbine" in Turbulence workshop - International symposium, University of Belgrade, Faculty of Mechanical Engineering, Book of Abstracts, Belgrade (2015),
https://hdl.handle.net/21.15107/rcub_machinery_5587 .

TY  - JOUR
AU  - Novković, Đorđe 
AU  - Lečić, Milan
AU  - Burazer, Jela M.
AU  - Radenković, Darko
PY  - 2014
UR  - https://machinery.mas.bg.ac.rs/handle/123456789/2050
AB  - U radu su urađene numeričke simulacije strujanja u maloj cevnoj turbini primenom softvera Ansys CFX. Simulacije su izvedene primenom tri različita modela turbulencije koji su bazirani na Rejnoldsovom osrednjavanju Navije-Stoksovih jednačina: k-ε , k-ω i SST. Za svaki od navedenih modela razmotreno je sedam različitih radnih režima turbine. Da bi se smanjilo korišćenje računarskih resursa izvedene su stacionarne simulacije strujanja. Za sve slučajeve dobijena je dobra numerička stabilnost i konvergencija rešenja. Radne krive turbine formirane su za svaki od izabranih modela turbulencije na osnovu rezultata izvedenih simulacija u različitim radnim režimima. Za optimalni radni režim turbine, u proizvoljno izabranom poprečnom preseku difuzora izračunati su profili brzina za svaki model turbulencije, kao i raspodela statičkog pritiska po konturama loptatica radnog kola turbine. Izvršeno je upoređivanje dobijenih performansi turbine i data je analiza dobijenih profila brzine i raspodele statičkog pritiska za izabrane modele turbulencije.
AB  - Numerical flow simulations in a small bulb turbine by the use of Ansys CFX software were performed in this paper. Simulations were performed for three different RANS-based models: k-ε , k-ω and SST. For each of these models, seven different operating regimes were considered. In order to reduce computational effort, steady state simulations were performed. In all cases, good numerical stability and convergence of solution were obtained. Based on the obtained results, performance curves for each of selected turbulence models in different operating regimes are formed. In turbine's optimal operating regime, velocity profiles in a selected cross section of the draft tube were calculated, as well as the static pressure distribution on runner blades. Comparison of obtained performance curves was performed. Analysis of the velocity profiles and distribution of static pressure are given for each of the selected turbulence model.
PB  - Univerzitet u Beogradu - Mašinski fakultet, Beograd
T2  - FME Transactions
T1  - Simulacije strujanja u maloj cevnoj turbini primenom dvojednačinskih modela turbulencije
T1  - Flow simulations in a small bulb turbine using two-equation turbulence models
EP  - 127
IS  - 2
SP  - 118
VL  - 42
DO  - 10.5937/fmet1402118N
ER  - 

@article{
author = "Novković, Đorđe  and Lečić, Milan and Burazer, Jela M. and Radenković, Darko",
year = "2014",
abstract = "U radu su urađene numeričke simulacije strujanja u maloj cevnoj turbini primenom softvera Ansys CFX. Simulacije su izvedene primenom tri različita modela turbulencije koji su bazirani na Rejnoldsovom osrednjavanju Navije-Stoksovih jednačina: k-ε , k-ω i SST. Za svaki od navedenih modela razmotreno je sedam različitih radnih režima turbine. Da bi se smanjilo korišćenje računarskih resursa izvedene su stacionarne simulacije strujanja. Za sve slučajeve dobijena je dobra numerička stabilnost i konvergencija rešenja. Radne krive turbine formirane su za svaki od izabranih modela turbulencije na osnovu rezultata izvedenih simulacija u različitim radnim režimima. Za optimalni radni režim turbine, u proizvoljno izabranom poprečnom preseku difuzora izračunati su profili brzina za svaki model turbulencije, kao i raspodela statičkog pritiska po konturama loptatica radnog kola turbine. Izvršeno je upoređivanje dobijenih performansi turbine i data je analiza dobijenih profila brzine i raspodele statičkog pritiska za izabrane modele turbulencije., Numerical flow simulations in a small bulb turbine by the use of Ansys CFX software were performed in this paper. Simulations were performed for three different RANS-based models: k-ε , k-ω and SST. For each of these models, seven different operating regimes were considered. In order to reduce computational effort, steady state simulations were performed. In all cases, good numerical stability and convergence of solution were obtained. Based on the obtained results, performance curves for each of selected turbulence models in different operating regimes are formed. In turbine's optimal operating regime, velocity profiles in a selected cross section of the draft tube were calculated, as well as the static pressure distribution on runner blades. Comparison of obtained performance curves was performed. Analysis of the velocity profiles and distribution of static pressure are given for each of the selected turbulence model.",
publisher = "Univerzitet u Beogradu - Mašinski fakultet, Beograd",
journal = "FME Transactions",
title = "Simulacije strujanja u maloj cevnoj turbini primenom dvojednačinskih modela turbulencije, Flow simulations in a small bulb turbine using two-equation turbulence models",
pages = "127-118",
number = "2",
volume = "42",
doi = "10.5937/fmet1402118N"
}

Novković, Đ., Lečić, M., Burazer, J. M.,& Radenković, D.. (2014). Simulacije strujanja u maloj cevnoj turbini primenom dvojednačinskih modela turbulencije. in FME Transactions
Univerzitet u Beogradu - Mašinski fakultet, Beograd., 42(2), 118-127.
https://doi.org/10.5937/fmet1402118N

Novković Đ, Lečić M, Burazer JM, Radenković D. Simulacije strujanja u maloj cevnoj turbini primenom dvojednačinskih modela turbulencije. in FME Transactions. 2014;42(2):118-127.
doi:10.5937/fmet1402118N .

Novković, Đorđe , Lečić, Milan, Burazer, Jela M., Radenković, Darko, "Simulacije strujanja u maloj cevnoj turbini primenom dvojednačinskih modela turbulencije" in FME Transactions, 42, no. 2 (2014):118-127,
https://doi.org/10.5937/fmet1402118N . .

TY  - JOUR
AU  - Radenković, Darko
AU  - Burazer, Jela M.
AU  - Novković, Đorđe 
PY  - 2014
UR  - https://machinery.mas.bg.ac.rs/handle/123456789/1945
AB  - U radu su primenjene dve vrste invarijantnih mapa kako bi se procenio stepen anizotropnosti turbulentnog vihornog strujanja. Korišćene su invarijantna mapa, koju su predložili Lamli i Njuman, kao i baricentrična mapa. Analizirane su razlike u vizuelnom predstavljanju stanja anizotropnosti i izvedene su matematičke osnove za obe mape. Analizom eksperimentalnih podataka je pokazano da postoji značajan uticaj vihora na anizotropnost turbulencije. Korišćenje mapa anizotropnosti pokazuje da su različite oblasti strujnog polja u vihornom strujanju okarakterisane različitim stanjima anizotropnosti.
AB  - Anisotropy invariant map proposed by Lumley and Newman and barycentric map proposed by Banerjee et al. were used in order to estimate the degree of anisotropy in turbulent swirl flow. The differences in visual interpretations of anisotropy states in these two maps were analyzed and mathematical basis of these two maps was derived. Experimental data reveal that there is significant influence of swirl on the anisotropy of turbulence. Anisotropy invariant mapping shows that different flow regions of swirl flow are characterized by different anisotropy states.
PB  - Univerzitet u Beogradu - Mašinski fakultet, Beograd
T2  - FME Transactions
T1  - Analiza anizotropnosti turbulentnog vihornog strujanja
T1  - Anisotropy analysis of turbulent swirl flow
EP  - 25
IS  - 1
SP  - 19
VL  - 42
DO  - 10.5937/fmet1401019R
ER  - 

@article{
author = "Radenković, Darko and Burazer, Jela M. and Novković, Đorđe ",
year = "2014",
abstract = "U radu su primenjene dve vrste invarijantnih mapa kako bi se procenio stepen anizotropnosti turbulentnog vihornog strujanja. Korišćene su invarijantna mapa, koju su predložili Lamli i Njuman, kao i baricentrična mapa. Analizirane su razlike u vizuelnom predstavljanju stanja anizotropnosti i izvedene su matematičke osnove za obe mape. Analizom eksperimentalnih podataka je pokazano da postoji značajan uticaj vihora na anizotropnost turbulencije. Korišćenje mapa anizotropnosti pokazuje da su različite oblasti strujnog polja u vihornom strujanju okarakterisane različitim stanjima anizotropnosti., Anisotropy invariant map proposed by Lumley and Newman and barycentric map proposed by Banerjee et al. were used in order to estimate the degree of anisotropy in turbulent swirl flow. The differences in visual interpretations of anisotropy states in these two maps were analyzed and mathematical basis of these two maps was derived. Experimental data reveal that there is significant influence of swirl on the anisotropy of turbulence. Anisotropy invariant mapping shows that different flow regions of swirl flow are characterized by different anisotropy states.",
publisher = "Univerzitet u Beogradu - Mašinski fakultet, Beograd",
journal = "FME Transactions",
title = "Analiza anizotropnosti turbulentnog vihornog strujanja, Anisotropy analysis of turbulent swirl flow",
pages = "25-19",
number = "1",
volume = "42",
doi = "10.5937/fmet1401019R"
}

Radenković, D., Burazer, J. M.,& Novković, Đ.. (2014). Analiza anizotropnosti turbulentnog vihornog strujanja. in FME Transactions
Univerzitet u Beogradu - Mašinski fakultet, Beograd., 42(1), 19-25.
https://doi.org/10.5937/fmet1401019R

Radenković D, Burazer JM, Novković Đ. Analiza anizotropnosti turbulentnog vihornog strujanja. in FME Transactions. 2014;42(1):19-25.
doi:10.5937/fmet1401019R .

Radenković, Darko, Burazer, Jela M., Novković, Đorđe , "Analiza anizotropnosti turbulentnog vihornog strujanja" in FME Transactions, 42, no. 1 (2014):19-25,
https://doi.org/10.5937/fmet1401019R . .

TY  - CONF
AU  - Radenković, Darko
AU  - Crnojevic, Cvetko
PY  - 2011
UR  - https://machinery.mas.bg.ac.rs/handle/123456789/6674
C3  - 3rd International Symposium Contemporary Problems of Fluid Mechanics
T1  - Calculation of flow parameters of the mixing chamber gas ejector that is used to transport the disperse phase
UR  - https://hdl.handle.net/21.15107/rcub_machinery_6674
ER  - 

@conference{
author = "Radenković, Darko and Crnojevic, Cvetko",
year = "2011",
journal = "3rd International Symposium Contemporary Problems of Fluid Mechanics",
title = "Calculation of flow parameters of the mixing chamber gas ejector that is used to transport the disperse phase",
url = "https://hdl.handle.net/21.15107/rcub_machinery_6674"
}

Radenković, D.,& Crnojevic, C.. (2011). Calculation of flow parameters of the mixing chamber gas ejector that is used to transport the disperse phase. in 3rd International Symposium Contemporary Problems of Fluid Mechanics.
https://hdl.handle.net/21.15107/rcub_machinery_6674

Radenković D, Crnojevic C. Calculation of flow parameters of the mixing chamber gas ejector that is used to transport the disperse phase. in 3rd International Symposium Contemporary Problems of Fluid Mechanics. 2011;.
https://hdl.handle.net/21.15107/rcub_machinery_6674 .

Radenković, Darko, Crnojevic, Cvetko, "Calculation of flow parameters of the mixing chamber gas ejector that is used to transport the disperse phase" in 3rd International Symposium Contemporary Problems of Fluid Mechanics (2011),
https://hdl.handle.net/21.15107/rcub_machinery_6674 .