Preferential concentration of particles by turbulence
- Department of Mechanical Engineering, Stanford University, Stanford, CA 94305, U.S.A.
- Received 18 February 1994
- Available online 18 February 2003
Abstract
Preferential concentration describes the accumulation of dense particles within specific regions of the instantaneous turbulence field. This phenomenon occurs in dilute particle-laden flows with particle time constants of the same order as an appropriately chosen turbulence time scale. The mechanisms which drive preferential concentration are centrifuging of particles away from vortex cores and accumulation of particles in convergence zones. Experimental and numerical studies are reviewed which demonstrate that preferential concentration occurs in a wide range of flows including plane and axisymmetric free shear flows, wall-bounded flows, homogeneous turbulent flows, and complex shear flows. The same basic mechanisms are active in all these flows but the specific effects and the definition of an appropriate time scale change from problem to problem. Preferential concentration has been shown to have a significant effect on droplet combustion, aerosol particle settling and turbulence modification by particles and is expected to be significant in numerous other applications. Current models describing preferential concentration and its global effects on the flow are inadequate.
Keywords
- particle concentration field;
- particle clustering;
- turbulence;
- particle laden flow;
- droplet clustering;
- particle-vortex interaction;
- particles
References
- Aggarwal and Uthuppan, 1993
Dispersion enhancement in the near region of an externally forced jet
Bull. Am. Phys. Soc., 38 (1993), p. 2279
- Bachalo et al., 1993
An investigation of spray interaction with large-scale eddies
Aiaa 93–0696 (1993)
- Bellan and Harstad, 1988
Turbulence effects during evaporation of drops in clusters
Int. J. Heat Mass Transfer, 31 (1988), pp. 1655–1668
- Berlemont et al., 1990
Particle-Lagrangian simulation in turbulent flows
Int. J. Multiphase Flow, 16 (1990), pp. 19–34
- Bernal and Roshko, 1986
Streamwise vortex structures in plane mixing layers
J. Fluid Mech., 170 (1986), pp. 499–525
- Brooke et al., 1994
Free-flight mixing and deposition of aerosols
(1994) Manuscript submitted for publication
- Brooke et al., 1992
Turbulent deposition and trapping of aerosols at a wall
Phys. Fluids A, 4 (1992), pp. 825–834
- Brown and Roshko, 1974
On the density effects and large structure in turbulent mixing layers
J. Fluid Mech., 64 (1974), pp. 693–704
- Chein and Chung, 1987
Effects of vortex pairing on particle dispersion in turbulent shear flows
Int. J. Multiphase Flow, 13 (1987), pp. 785–802
- Chein and Chung, 1988
Particle dynamics in a gas-particle flow over normal and inclined plates
Chem. Engng Sci., 43 (1988), pp. 1621–1636
- Chung and Troutt, 1988
Simulation of particle dispersion in an axisymmetric jet
J. Fluid Mech., 186 (1988), pp. 199–222
- Crowe et al., 1988
Particle mixing in free shear flows
Prog. Energy Combust. Sci., 14 (1988), pp. 171–194
- Crowe et al., 1993
Particle dispersion by organized turbulent structures
M.C. Roco (Ed.), Particulate Two-phase Flows, Butterworth-Heinemann, New York (1993) Chap. 18
- Cuzzi
- Cuzzi, J. 1994 Personal communication.
- Deutsch and Simonin, 1991
Large eddy simulation applied to the modelling of particulate transport coefficients in turbulent two-phase flows
Proc. 8th Symp. Turbulent Shear Flows, Munich (1991), pp. 10-1-1–10-1-6
- Dyer and Soulsby, 1988
Sand transport on the continental shelf
Ann. Rev. Fluid Mech., 20 (1988), pp. 295–324
- Elghobashi and Abou-Arab, 1983
A two-equation model for two-phase flows
Phys. Fluids, 26 (1983), pp. 931–938
- Elghobashi and Truesdell, 1993
On the two-way interaction between homogeneous turbulence and dispersed solid particles. 1: turbulence modification
Phys. Fluids A, 5 (1993), pp. 1790–1801
- Eswaran and Pope, 1988
An examination of forcing in direct numerical simulations of turbulence
Comput. Fluids, 16 (1988), pp. 257–278
- Fessler et al., 1994
Preferential concentration of heavy particles in a turbulent channel flow
Phys. Fluids (1994) Submitted to
- Fichot et al., 1993
Unsteady evaporation and combustion of a drop cluster inside a vortex
Aiaa 93–0695 (1993)
- Fung and Perkins, 1989
Particle trajectories in turbulent flow generated by true-varying random Fourier modes
H.H. Fernholz, H.E. Fiedler (Eds.), Advances in Turbulence 2, Springer, New York (1989)
- Ganan-Calvo and Lasheras, 1991
The dynamics and mixing of small spherical particles in a plane, free shear layer
Phys. Fluids A, 3 (1991), pp. 1207–1217
- Glawe and Samimy, 1993
Dispersion of solid particles in compressible mixing layers
J. Propulsion Power, 9 (1993), pp. 83–89
- Gore and Crowe, 1989
Effect of particle size on modulating turbulent intensity
Int. J. Multiphase Flow, 15 (1989), pp. 279–285
- Hansell et al., 1992
A simulation of particle dispersion in a turbulent jet
Int. J. Multiphase Flow, 18 (1992), pp. 559–576
- Hardalupas et al., 1990
Velocity and size characteristics of liquid-fuelled flames stabilized by a swirl burner
Proc. R. Soc. Lond., A428 (1990), pp. 129–155
- Hardalupas et al., 1992
Particle dispersion in a vertical round sudden-expansion flow
Proc. R. Soc. Lond., A341 (1992), pp. 411–442
- Hetsroni, 1989
Particles-turbulence interaction
Int. J. Multiphase Flow, 15 (1989), pp. 735–746
- Hunt et al., 1987
Big whorls carry little whorls
Proceedings of the Summer Program 1987, Center for Turbulence Research, Stanford University, Calif., (1987)
- Hunt et al., 1988
Eddies, streams and convergence zones in turbulent flows
Proc. of the Summer Program 1988, Center for Turbulence Research, Stanford University, Calif., (1988), pp. 193–208
- Ishima et al., 1993a
Effect of particle residence time on particle dispersion in a plane mixing layer
Trans. ASME, J. Fluids Engng, 115 (1993), pp. 751–759
- Ishima et al., 1993b
Particle dispersion in a flow field with vortex shedding behind a pair of vortices
ASME FED-Vol 166, Gas—Solid Flows (1993), pp. 215–220
- Kada and Hanratty, 1960
Effects of solids on turbulence in a field
AIChE Jl, 6 (1960), pp. 624–630
- Kamalu et al., 1988
Particle dispersion by ordered motion in mixing layers
ASME Cavitation Multiphase Flow Forum FED, 64 (1988), pp. 150–154
- Kallio and Reeks, 1989
A numerical simulation of particle deposition in turbulent boundary layers
Int. J. Multiphase Flow, 15 (1989), pp. 433–446
- Kobayashi et al., 1988
Dispersed phase transport in a plane mixing layer
Transport Phenomena in Turbulent FlowHemisphere, New York (1988), pp. 433–446
- Kraichnan, 1970
Diffusion by a random velocity field
Phys. Fluids, 13 (1970), pp. 22–31
- Kulick et al., 1993
On the interactions between particles and turbulence in a fully-developed channel flow in air
Report MD-66Department of Mechanical Engineering Stanford University, Calif., (1993)
- Laitone, 1981
A numerical solution for gas-particles flows at high Reynolds number
J. appl. Mech., 48 (1981), pp. 465–471