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arXiv · 2509.00111

A correction tensor for approximating drag on slow-moving particles of arbitrary shape

Duncan A. Lockerby
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Abstract

A new form of the Cunningham correction factor is presented that requires no experimental fitting. It is expanded to provide a predictive heuristic for non-spherical particles, via definition of a "correction tensor''. Its accuracy is tested against experiments and kinetic theory for the sphere, and stochastic solutions to the Boltzmann equation for a range of spheroids. It represents a simple, general tool for approximating transport properties of non-spherical micro/nano particles in a gas.

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Duncan A. Lockerby. 2025-08-28. A correction tensor for approximating drag on slow-moving particles of arbitrary shape. https://doi.org/10.1017/jfm.2025.10776

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