Preferential concentration of particles by turbulence

Kyle Squires, John K. Eaton

Research output: Contribution to journalArticle

604 Citations (Scopus)

Abstract

Direct numerical simulation of isotropic turbulence was used to investigate the effect of turbulence on the concentration fields of heavy particles. The hydrodynamic field was computed using 643 points and a statistically stationary flow was obtained by forcing the low-wave-number components of the velocity field. The particles used in the simulations were time advanced according to Stokes drag law and were also assumed to be much more dense than the fluid. Properties of the particle cloud were obtained by following the trajectories of 1 000 000 particles through the simulated flow fields. Three values of the ratio of the particle time constant to large-scale turbulence time scale were used in the simulations: 0.075, 0.15, and 0.52. The simulations show that the particles collect preferentially in regions of low vorticity and high strain rate. This preferential collection was most pronounced for the intermediate particle time constant (0.15) and it was also found that the instantaneous number density was as much as 25 times the mean value for these simulations. The fact that dense particles collect in regions of low vorticity and high strain in turn implies that turbulence may actually inhibit rather than enhance mixing of particles.

Original languageEnglish (US)
Pages (from-to)1169-1178
Number of pages10
JournalPhysics of Fluids A
Volume3
Issue number5
StatePublished - 1991
Externally publishedYes

Fingerprint

Turbulence
turbulence
Vorticity
Direct numerical simulation
Drag
Strain rate
Flow fields
vorticity
time constant
Hydrodynamics
Trajectories
simulation
Fluids
isotropic turbulence
direct numerical simulation
drag
strain rate
flow distribution
velocity distribution
hydrodynamics

ASJC Scopus subject areas

  • Condensed Matter Physics
  • Physics and Astronomy(all)
  • Mechanics of Materials
  • Computational Mechanics
  • Fluid Flow and Transfer Processes
  • Engineering(all)

Cite this

Preferential concentration of particles by turbulence. / Squires, Kyle; Eaton, John K.

In: Physics of Fluids A, Vol. 3, No. 5, 1991, p. 1169-1178.

Research output: Contribution to journalArticle

Squires, Kyle ; Eaton, John K. / Preferential concentration of particles by turbulence. In: Physics of Fluids A. 1991 ; Vol. 3, No. 5. pp. 1169-1178.
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