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arXiv · 1810.10285

Flow structures govern particle collisions in turbulence

Jason R. Picardo·Lokahith Agasthya·Rama Govindarajan·Samriddhi Sankar Ray
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Abstract

The role of the spatial structure of a turbulent flow in enhancing particle collision rates in suspensions is an open question. We show and quantify, as a function of particle inertia, the correlation between the multiscale structures of turbulence and particle collisions: Straining zones contribute predominantly to rapid head-on collisions compared to vortical regions. We also discover the importance of vortex-strain worm-rolls, which goes beyond ideas of preferential concentration and may explain the rapid growth of aggregates in natural processes, such as the initiation of rain in warm clouds.

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Jason R. Picardo, Lokahith Agasthya, Rama Govindarajan, Samriddhi Sankar Ray. 2019-03-26. Flow structures govern particle collisions in turbulence. https://doi.org/10.1103/physrevfluids.4.032601

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