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arXiv · 2609.21406

Relative velocity between a particle and turbulence

Yutaro Motoori·Daiki Watanabe·Susumu Goto
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Abstract

The relative velocity between a particle and the surrounding fluid is a key quantity that determines the various phenomena of particle-laden turbulence, such as particle clustering and turbulence modulation due to particles. We theoretically derive the expression for the relative velocity of a particle laden in turbulence by extending the argument of Balachandar (2009). This derivation provides a simplified form of the analytical model of Berk and Coletti (2024), and it makes the underlying physical assumptions explicit. Using direct numerical simulation data of turbulence in a periodic cube and turbulent channel flow, we demonstrate the validity of the derived expression, and show that it also holds for non-spherical particles and droplets.

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Yutaro Motoori, Daiki Watanabe, Susumu Goto. 2026-09-18. Relative velocity between a particle and turbulence. https://arxiv.org/abs/2609.21406

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