Turbulent Swirl Flow Laser Research
Abstract
Тhree-dimensional, non-homogeneous, anisotropic turbulent velocity fields require complex
experimental and theoretical approach, associated with the complex numerical procedures.
Analysis of the vortex core and the statistical characteristics of turbulent swirl flow in straight pipe
behind axial fans are based on the latest experimental researches. Contemporary laser based
measuring techniques, such as stereo particle image velocimetry (SPIV), high speed SPIV
(HSSPIV) and one- and two-component laser Doppler anemometry (LDA) systems are applied.
Influence of the type and operating regime of axial fan on turbulence structure and turbulent
transfer mechanism is studied.
The phenomenon of the vortex core precession as well as the phenomenon of non-local
turbulent transfer and non-gradient turbulent diffusion is studied. In addition, the effects of
Reynolds and swirl number, and the effects of rotation speed and blade angle on these
phenomena are investigated. The physical inter...pretation of experimental data indicates
significant structural properties of a turbulent vortex core and a shear layer. Experimental and
correlation analysis examines the evolution of statistical characteristics and correlation
moments, which is the basis for drawing conclusions about the extreme turbulence nonhomogeneity
and anisotropy.
The HSSPIV measured distributions of turbulent stresses enabled the formation of anisotropy
invariant maps for various fan blade angles, so the important conclusions about the influence of
fan duty point on anisotropy and turbulence structure in the core, shear layer and sound flow
region were obtained. Additional pieces of information on turbulent structure physics were
obtained on the basis of experimentally determined autocorrelation functions and turbulence
integral scales, and also by the analysis of spectral functions of circumferential velocity
fluctuations. These considerations provide adequate physical interpretation of complex
interactions between the average and fluctuating velocity fields that characterize the processes of
turbulent transfer. Joint experimental and theoretical-numerical analysis allowed for meaningful
and important conclusions about various effects of different axial fan impellers on the turbulent
vortex core and turbulence structure.
Source:
CTR Tea Seminar, Friday, June 6, CTR Conference Room, 2014Collections
Institution/Community
Mašinski fakultetTY - GEN AU - Čantrak, Đorđe PY - 2014 UR - https://machinery.mas.bg.ac.rs/handle/123456789/6860 AB - Тhree-dimensional, non-homogeneous, anisotropic turbulent velocity fields require complex experimental and theoretical approach, associated with the complex numerical procedures. Analysis of the vortex core and the statistical characteristics of turbulent swirl flow in straight pipe behind axial fans are based on the latest experimental researches. Contemporary laser based measuring techniques, such as stereo particle image velocimetry (SPIV), high speed SPIV (HSSPIV) and one- and two-component laser Doppler anemometry (LDA) systems are applied. Influence of the type and operating regime of axial fan on turbulence structure and turbulent transfer mechanism is studied. The phenomenon of the vortex core precession as well as the phenomenon of non-local turbulent transfer and non-gradient turbulent diffusion is studied. In addition, the effects of Reynolds and swirl number, and the effects of rotation speed and blade angle on these phenomena are investigated. The physical interpretation of experimental data indicates significant structural properties of a turbulent vortex core and a shear layer. Experimental and correlation analysis examines the evolution of statistical characteristics and correlation moments, which is the basis for drawing conclusions about the extreme turbulence nonhomogeneity and anisotropy. The HSSPIV measured distributions of turbulent stresses enabled the formation of anisotropy invariant maps for various fan blade angles, so the important conclusions about the influence of fan duty point on anisotropy and turbulence structure in the core, shear layer and sound flow region were obtained. Additional pieces of information on turbulent structure physics were obtained on the basis of experimentally determined autocorrelation functions and turbulence integral scales, and also by the analysis of spectral functions of circumferential velocity fluctuations. These considerations provide adequate physical interpretation of complex interactions between the average and fluctuating velocity fields that characterize the processes of turbulent transfer. Joint experimental and theoretical-numerical analysis allowed for meaningful and important conclusions about various effects of different axial fan impellers on the turbulent vortex core and turbulence structure. T2 - CTR Tea Seminar, Friday, June 6, CTR Conference Room T1 - Turbulent Swirl Flow Laser Research UR - https://hdl.handle.net/21.15107/rcub_machinery_6860 ER -
@misc{ author = "Čantrak, Đorđe", year = "2014", abstract = "Тhree-dimensional, non-homogeneous, anisotropic turbulent velocity fields require complex experimental and theoretical approach, associated with the complex numerical procedures. Analysis of the vortex core and the statistical characteristics of turbulent swirl flow in straight pipe behind axial fans are based on the latest experimental researches. Contemporary laser based measuring techniques, such as stereo particle image velocimetry (SPIV), high speed SPIV (HSSPIV) and one- and two-component laser Doppler anemometry (LDA) systems are applied. Influence of the type and operating regime of axial fan on turbulence structure and turbulent transfer mechanism is studied. The phenomenon of the vortex core precession as well as the phenomenon of non-local turbulent transfer and non-gradient turbulent diffusion is studied. In addition, the effects of Reynolds and swirl number, and the effects of rotation speed and blade angle on these phenomena are investigated. The physical interpretation of experimental data indicates significant structural properties of a turbulent vortex core and a shear layer. Experimental and correlation analysis examines the evolution of statistical characteristics and correlation moments, which is the basis for drawing conclusions about the extreme turbulence nonhomogeneity and anisotropy. The HSSPIV measured distributions of turbulent stresses enabled the formation of anisotropy invariant maps for various fan blade angles, so the important conclusions about the influence of fan duty point on anisotropy and turbulence structure in the core, shear layer and sound flow region were obtained. Additional pieces of information on turbulent structure physics were obtained on the basis of experimentally determined autocorrelation functions and turbulence integral scales, and also by the analysis of spectral functions of circumferential velocity fluctuations. These considerations provide adequate physical interpretation of complex interactions between the average and fluctuating velocity fields that characterize the processes of turbulent transfer. Joint experimental and theoretical-numerical analysis allowed for meaningful and important conclusions about various effects of different axial fan impellers on the turbulent vortex core and turbulence structure.", journal = "CTR Tea Seminar, Friday, June 6, CTR Conference Room", title = "Turbulent Swirl Flow Laser Research", url = "https://hdl.handle.net/21.15107/rcub_machinery_6860" }
Čantrak, Đ.. (2014). Turbulent Swirl Flow Laser Research. in CTR Tea Seminar, Friday, June 6, CTR Conference Room. https://hdl.handle.net/21.15107/rcub_machinery_6860
Čantrak Đ. Turbulent Swirl Flow Laser Research. in CTR Tea Seminar, Friday, June 6, CTR Conference Room. 2014;. https://hdl.handle.net/21.15107/rcub_machinery_6860 .
Čantrak, Đorđe, "Turbulent Swirl Flow Laser Research" in CTR Tea Seminar, Friday, June 6, CTR Conference Room (2014), https://hdl.handle.net/21.15107/rcub_machinery_6860 .