REYNOLDS NUMBER INFLUENCE ON INTEGRAL AND STATISTICAL CHARACTERISTICS OF THE TURBULENT SWIRL FLOW IN STRAIGHT CONICAL DIFFUSER
Abstract
Results of experimental investigations of the turbulent swirl flow in straight conical diffuser
are presented in this paper. Diffusers have the inlet diameter 0.4 m and total divergence angles
8.6°. The incompressible swirl flow field is generated by the axial fan with outer diameter 0.397
m. Measurements are performed in one measuring sections downstream the axial fan impeller, i.e.
in conical diffuser (z/R0 = 1) with one-component laser Doppler anemometry (LDA) system, for
four flow regimes. Axial and circumferential velocities are measured. Reynolds numbers
calculated on the basis of the average axial velocity, ranges from 149857 to 216916. Integral
parameters, such as volume flow rate, average circulation and swirl number are determined.
Statistical characteristics are calculated such as level of turbulence, skewness and flatness factors.
The highest levels of turbulence for axial velocity are reached in the region 0.4 < r/R < 0.6, where
D = 2R. The highest levels of turb...ulence for circumferential velocity are reached in the region
around r/R = 0.4 for lower values of circulation, respectively in the core region for higher values
of circulation.
Keywords:
turbulence / swirl / flow / fan / diffuser / LDASource:
6th International Congress of Serbian Society of Mechanics, Mountain Tara, Serbia, 19-21 June, Conference Proceedings, Minisymposium M2: Turbulence, Eds.: Lazarević M. et al., paper No. M2e, 6 pages, 2017Publisher:
- Serbian Society of Mechanics
Funding / projects:
- Application of Novel Measurement and Computational Techniques on Investigation of Air Flow in Ventilation Systems of Energy Extremely Efficient (“Passive”) Buildings (RS-MESTD-Technological Development (TD or TR)-35046)
- Bilateral cooperation between MESTD, Serbia and Ministry of Science, Montenegro (2016-2018), coordinated between University of Belgrade, Faculty of Mechanical Engineering and University of Montenegro, Faculty of Mechanical Engineering: Investigation of the influence of turbulent swirl flow on the energy parameters of the axial fans by use of the contemporary measurement techniques, what is gratefully acknowledged.
Collections
Institution/Community
Mašinski fakultetTY - CONF AU - Ilić, Dejan AU - Čantrak, Đorđe AU - Janković, Novica PY - 2017 UR - https://machinery.mas.bg.ac.rs/handle/123456789/5235 AB - Results of experimental investigations of the turbulent swirl flow in straight conical diffuser are presented in this paper. Diffusers have the inlet diameter 0.4 m and total divergence angles 8.6°. The incompressible swirl flow field is generated by the axial fan with outer diameter 0.397 m. Measurements are performed in one measuring sections downstream the axial fan impeller, i.e. in conical diffuser (z/R0 = 1) with one-component laser Doppler anemometry (LDA) system, for four flow regimes. Axial and circumferential velocities are measured. Reynolds numbers calculated on the basis of the average axial velocity, ranges from 149857 to 216916. Integral parameters, such as volume flow rate, average circulation and swirl number are determined. Statistical characteristics are calculated such as level of turbulence, skewness and flatness factors. The highest levels of turbulence for axial velocity are reached in the region 0.4 < r/R < 0.6, where D = 2R. The highest levels of turbulence for circumferential velocity are reached in the region around r/R = 0.4 for lower values of circulation, respectively in the core region for higher values of circulation. PB - Serbian Society of Mechanics C3 - 6th International Congress of Serbian Society of Mechanics, Mountain Tara, Serbia, 19-21 June, Conference Proceedings, Minisymposium M2: Turbulence, Eds.: Lazarević M. et al., paper No. M2e, 6 pages T1 - REYNOLDS NUMBER INFLUENCE ON INTEGRAL AND STATISTICAL CHARACTERISTICS OF THE TURBULENT SWIRL FLOW IN STRAIGHT CONICAL DIFFUSER UR - https://hdl.handle.net/21.15107/rcub_machinery_5235 ER -
@conference{ author = "Ilić, Dejan and Čantrak, Đorđe and Janković, Novica", year = "2017", abstract = "Results of experimental investigations of the turbulent swirl flow in straight conical diffuser are presented in this paper. Diffusers have the inlet diameter 0.4 m and total divergence angles 8.6°. The incompressible swirl flow field is generated by the axial fan with outer diameter 0.397 m. Measurements are performed in one measuring sections downstream the axial fan impeller, i.e. in conical diffuser (z/R0 = 1) with one-component laser Doppler anemometry (LDA) system, for four flow regimes. Axial and circumferential velocities are measured. Reynolds numbers calculated on the basis of the average axial velocity, ranges from 149857 to 216916. Integral parameters, such as volume flow rate, average circulation and swirl number are determined. Statistical characteristics are calculated such as level of turbulence, skewness and flatness factors. The highest levels of turbulence for axial velocity are reached in the region 0.4 < r/R < 0.6, where D = 2R. The highest levels of turbulence for circumferential velocity are reached in the region around r/R = 0.4 for lower values of circulation, respectively in the core region for higher values of circulation.", publisher = "Serbian Society of Mechanics", journal = "6th International Congress of Serbian Society of Mechanics, Mountain Tara, Serbia, 19-21 June, Conference Proceedings, Minisymposium M2: Turbulence, Eds.: Lazarević M. et al., paper No. M2e, 6 pages", title = "REYNOLDS NUMBER INFLUENCE ON INTEGRAL AND STATISTICAL CHARACTERISTICS OF THE TURBULENT SWIRL FLOW IN STRAIGHT CONICAL DIFFUSER", url = "https://hdl.handle.net/21.15107/rcub_machinery_5235" }
Ilić, D., Čantrak, Đ.,& Janković, N.. (2017). REYNOLDS NUMBER INFLUENCE ON INTEGRAL AND STATISTICAL CHARACTERISTICS OF THE TURBULENT SWIRL FLOW IN STRAIGHT CONICAL DIFFUSER. in 6th International Congress of Serbian Society of Mechanics, Mountain Tara, Serbia, 19-21 June, Conference Proceedings, Minisymposium M2: Turbulence, Eds.: Lazarević M. et al., paper No. M2e, 6 pages Serbian Society of Mechanics.. https://hdl.handle.net/21.15107/rcub_machinery_5235
Ilić D, Čantrak Đ, Janković N. REYNOLDS NUMBER INFLUENCE ON INTEGRAL AND STATISTICAL CHARACTERISTICS OF THE TURBULENT SWIRL FLOW IN STRAIGHT CONICAL DIFFUSER. in 6th International Congress of Serbian Society of Mechanics, Mountain Tara, Serbia, 19-21 June, Conference Proceedings, Minisymposium M2: Turbulence, Eds.: Lazarević M. et al., paper No. M2e, 6 pages. 2017;. https://hdl.handle.net/21.15107/rcub_machinery_5235 .
Ilić, Dejan, Čantrak, Đorđe, Janković, Novica, "REYNOLDS NUMBER INFLUENCE ON INTEGRAL AND STATISTICAL CHARACTERISTICS OF THE TURBULENT SWIRL FLOW IN STRAIGHT CONICAL DIFFUSER" in 6th International Congress of Serbian Society of Mechanics, Mountain Tara, Serbia, 19-21 June, Conference Proceedings, Minisymposium M2: Turbulence, Eds.: Lazarević M. et al., paper No. M2e, 6 pages (2017), https://hdl.handle.net/21.15107/rcub_machinery_5235 .