Numerical Study for Estimating Fluid Forces Acting on a Rotating Sphere in a Homogeneous Shear Flow.

Abstract

Fluid forces (drag and lift force) acting on a rotating sphere in a homogeneous linear shear flow are numeriacally studied by means of a three-dimensional numerical simulation based on a marker and cell (MAC) method. The effects of particle rotation speed, shear rate of fluid and particle Reynolds number Re con the fluid forces are estimated under various conditions from numerical predictions of drag and lift force. The results show that average lift force acts on a stationary sphere from the high-speed side to the low-speed side in a homogeneous linear shear flow with high particle Reynolds number of Re>100. The direction of the lift force is quite different between low and high particle Reynolds numbers. The difference can be explained in terms of the pressure acting on the surface of a sphere. The direction of the lift force for high particle Reynolds numbers is also examined through a preliminary. experiment in glycerin solution flow with a linear shear.