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Updated: Jun 23, 2026
11:03
An Analog Macroscopic Technique for Studying Molecular Hydrodynamic Processes in Dense Gases and Liquids
Published on: December 4, 2017
Stochastic transport of particles in straining flows
D C Swailes1, Y Ammar, M W Reeks
1School of Mechanical & Systems Engineering, Newcastle University, Newcastle upon Tyne NE1 7RU, United Kingdom. d.c.swailes@ncl.ac.uk
Summary
Stochastic forcing and straining flow create stable particle distributions in turbulent flows. Particle inertia influences these distributions and leads to unique velocity patterns, offering insights into particle transport dynamics.
Area of Science:
- Fluid Dynamics
- Particle Transport
- Statistical Mechanics
Background:
- Particle segregation in turbulent flows is complex.
- Understanding particle distribution requires analyzing forces like straining flow and stochastic forcing.
Purpose of the Study:
- Investigate particle segregation features in turbulent flow.
- Analyze phase-space number density under combined straining flow and stochastic forcing.
- Examine the influence of particle inertia and strain rate.
Main Methods:
- Utilized a Fokker-Planck model to simulate particle behavior.
- Analyzed phase-space distributions of particles in straining flow fields.
- Assessed the Chapman-Enskog approximation for closure models.
Main Results:
- Nonsingular steady-state distributions were generated, unlike the zero strain case.
- Diffusional effects from stochastic forcing prevented singular distributions along stagnation lines.
- Particle inertia (Stokes number) significantly altered distribution forms.
- Strain rate was found to attenuate particle kinetic stresses.
- Large third-order velocity moments developed above a critical Stokes number.
Conclusions:
- The study reveals mechanisms for particle distribution and segregation in turbulent flows.
- Findings provide a testbed for closure models of third-order velocity moments.
- Particle inertia and flow dynamics critically influence particle behavior and distribution.
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