Preferential concentration of heavy particles in turbulence
Particle-laden flows are of relevant interest in many industrial and natural systems. When the carrier flow is turbulent, a striking feature is the phenomenon called preferential concentration: particles denser than the fluid have the tendency to inhomogeneously distribute in space, forming clusters...
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| Acceso en línea: | http://hdl.handle.net/20.500.12110/paper_14685248_v15_n5_p293_Obligado |
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todo:paper_14685248_v15_n5_p293_Obligado2023-10-03T16:17:28Z Preferential concentration of heavy particles in turbulence Obligado, M. Teitelbaum, T. Cartellier, A. Mininni, P. Bourgoin, M. turbulent mixing turbulent multi-phase flows Reynolds number Velocity Clustering mechanism Clustering properties Experimental conditions Homogeneous and isotropic Homogeneous isotropic turbulence Particle laden flows Preferential concentration Turbulent mixing Turbulence acceleration cluster analysis concentration (composition) flow modeling Reynolds number Stokes formula turbulence turbulent mixing Particle-laden flows are of relevant interest in many industrial and natural systems. When the carrier flow is turbulent, a striking feature is the phenomenon called preferential concentration: particles denser than the fluid have the tendency to inhomogeneously distribute in space, forming clusters and depleted regions. We present an investigation of clustering of small water droplets in homogeneous and isotropic active-grid-generated turbulence. We investigate the effect of Reynolds number (R&lamda;) and Stokes number (St) on particles clustering in the range R&lamda; ∼ 200-400 and St ∼ 2-10. Using Voronoï diagrams, we characterise clustering level and cluster properties (geometry, typical dimension and fractality). The exact same Voronoï analysis is then applied to investigate clustering properties of specific topological points of the velocity field of homogeneous isotropic turbulence obtained from direct numerical simulations at R ∼ 220 and 300. The goal is to compare clustering properties of actual particles with those of such points in order to explore the relevance of possible clustering mechanisms, including centrifugal effects (heavy particles sampling preferentially low-vorticity regions) and sweep-stick mechanisms (heavy particles preferentially sticking to low-acceleration points). Our study points towards a leading role of zero-acceleration points and sweep-stick effects, at least for the experimental conditions considered in this study. © 2014 Taylor and Francis. Fil:Teitelbaum, T. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina. Fil:Mininni, P. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina. JOUR info:eu-repo/semantics/openAccess http://creativecommons.org/licenses/by/2.5/ar http://hdl.handle.net/20.500.12110/paper_14685248_v15_n5_p293_Obligado |
| institution |
Universidad de Buenos Aires |
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I-28 |
| repository_str |
R-134 |
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Biblioteca Digital - Facultad de Ciencias Exactas y Naturales (UBA) |
| topic |
turbulent mixing turbulent multi-phase flows Reynolds number Velocity Clustering mechanism Clustering properties Experimental conditions Homogeneous and isotropic Homogeneous isotropic turbulence Particle laden flows Preferential concentration Turbulent mixing Turbulence acceleration cluster analysis concentration (composition) flow modeling Reynolds number Stokes formula turbulence turbulent mixing |
| spellingShingle |
turbulent mixing turbulent multi-phase flows Reynolds number Velocity Clustering mechanism Clustering properties Experimental conditions Homogeneous and isotropic Homogeneous isotropic turbulence Particle laden flows Preferential concentration Turbulent mixing Turbulence acceleration cluster analysis concentration (composition) flow modeling Reynolds number Stokes formula turbulence turbulent mixing Obligado, M. Teitelbaum, T. Cartellier, A. Mininni, P. Bourgoin, M. Preferential concentration of heavy particles in turbulence |
| topic_facet |
turbulent mixing turbulent multi-phase flows Reynolds number Velocity Clustering mechanism Clustering properties Experimental conditions Homogeneous and isotropic Homogeneous isotropic turbulence Particle laden flows Preferential concentration Turbulent mixing Turbulence acceleration cluster analysis concentration (composition) flow modeling Reynolds number Stokes formula turbulence turbulent mixing |
| description |
Particle-laden flows are of relevant interest in many industrial and natural systems. When the carrier flow is turbulent, a striking feature is the phenomenon called preferential concentration: particles denser than the fluid have the tendency to inhomogeneously distribute in space, forming clusters and depleted regions. We present an investigation of clustering of small water droplets in homogeneous and isotropic active-grid-generated turbulence. We investigate the effect of Reynolds number (R&lamda;) and Stokes number (St) on particles clustering in the range R&lamda; ∼ 200-400 and St ∼ 2-10. Using Voronoï diagrams, we characterise clustering level and cluster properties (geometry, typical dimension and fractality). The exact same Voronoï analysis is then applied to investigate clustering properties of specific topological points of the velocity field of homogeneous isotropic turbulence obtained from direct numerical simulations at R ∼ 220 and 300. The goal is to compare clustering properties of actual particles with those of such points in order to explore the relevance of possible clustering mechanisms, including centrifugal effects (heavy particles sampling preferentially low-vorticity regions) and sweep-stick mechanisms (heavy particles preferentially sticking to low-acceleration points). Our study points towards a leading role of zero-acceleration points and sweep-stick effects, at least for the experimental conditions considered in this study. © 2014 Taylor and Francis. |
| format |
JOUR |
| author |
Obligado, M. Teitelbaum, T. Cartellier, A. Mininni, P. Bourgoin, M. |
| author_facet |
Obligado, M. Teitelbaum, T. Cartellier, A. Mininni, P. Bourgoin, M. |
| author_sort |
Obligado, M. |
| title |
Preferential concentration of heavy particles in turbulence |
| title_short |
Preferential concentration of heavy particles in turbulence |
| title_full |
Preferential concentration of heavy particles in turbulence |
| title_fullStr |
Preferential concentration of heavy particles in turbulence |
| title_full_unstemmed |
Preferential concentration of heavy particles in turbulence |
| title_sort |
preferential concentration of heavy particles in turbulence |
| url |
http://hdl.handle.net/20.500.12110/paper_14685248_v15_n5_p293_Obligado |
| work_keys_str_mv |
AT obligadom preferentialconcentrationofheavyparticlesinturbulence AT teitelbaumt preferentialconcentrationofheavyparticlesinturbulence AT cartelliera preferentialconcentrationofheavyparticlesinturbulence AT mininnip preferentialconcentrationofheavyparticlesinturbulence AT bourgoinm preferentialconcentrationofheavyparticlesinturbulence |
| _version_ |
1782026461092249600 |