Inertial-particle dynamics in turbulent flows: caustics, concentration fluctuations, and random uncorrelated motion

Abstract

We discuss the relation between three recent approaches of describing the dynamics and the spatial distribution of particles suspended in turbulent flows: phase-space singularities in the inertial particle dynamics (caustics), real-space singularities of the deformation tensor, and random uncorrelated motion. We discuss how the phase- and real-space singularities are related. Their formation is well understood in terms of a local theory. We discuss implications for random uncorrelated motion. Our results are supported by results of direct numerical simulations of inertial particles in model flows.

20 pages, 9 figures, as published

References in corpus (7)

• Caustic activation of rain showers
• Sling effect in collisions of water droplets in turbulent clouds
• Distribution of relative velocities in turbulent aerosols
• Ergodic and non-ergodic clustering of inertial particles
• Unmixing in Random Flows
• Stochastic suspensions of heavy particles
• Correlation Dimension of Inertial Particles in Random Flows

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