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arXiv · 2108.01777

Fluid-mediated sources of granular temperature at finite Reynolds numbers

Aaron M. Lattanzi·Vahid Tavanashad·Shankar Subramaniam·Jesse Capecelatro
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Abstract

We derive analytical solutions for hydrodynamic sources and sinks to granular temperature in moderately dense suspensions of elastic particles at finite Reynolds numbers. Modeling the neighbor-induced drag disturbances with a Langevin equation allows an exact solution for the joint fluctuating acceleration-velocity distribution function $P\left(v^{\prime},a^{\prime};t\right)$. Quadrant-conditioned covariance integrals of $P\left(v^{\prime},a^{\prime};t\right)$ yield the hydrodynamic source and sink that dictate the evolution of granular temperature. Analytical predictions are in agreement with benchmark data obtained from particle-resolved direct numerical simulations and show promise as a general theory from gas--solid to bubbly flows.

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Aaron M. Lattanzi, Vahid Tavanashad, Shankar Subramaniam, Jesse Capecelatro. 2021-08-03. Fluid-mediated sources of granular temperature at finite Reynolds numbers. https://doi.org/10.1017/jfm.2022.351

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