Accurate hydrodynamic force and torque correlations for prolate spheroids from Stokes regime to high Reynolds numbers
In the process industry, particles are often transported and processed in a gas or liquid environment. Because hydrodynamic flows are very sensitive to scale, it is very beneficial to have models that can predict multi-phase flows in scaled-up process equipment. Most of these models still assume that the particles are spherical, for which hydrodynamic drag forces are relatively well known. However, the particles that are processed are increasingly much of non-spherical shape.
Especially for highly non-spherical particles, hydrodynamic lift forces and torque are equally important as drag, but accurate expressions are largely absent. Johan Padding has worked with researchers at the National Energy Technology Laboratory (NETL) in the USA, including his former PhD student Sathish Sanjeevi, to determine accurate correlations for drag, lift and torque on prolate spheroids, valid for a large range of aspect ratios, Reynolds numbers and angles of attack, and recently published their results in Chemical Engineering Journal. The derived correlations allow for much more accurate simulations of multiphase flows with highly elongated particles.
