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

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.