STOKESIAN FLOW OF A MICROPOLAR FLUID PAST A SPHERE.

A creeping flow of micropolar fluids past a sphere is presented by using a vector potential. As a boundary condition, an intermediate spin condition between zero spin and one-half of vorticity is used. Analytical expressions for velocity, vorticity, microrotation in the flow field and drag on the sphere are obtained, which are completely characterized by three dimensionless parameters, i. e. the ratio of vortex viscosity to shear viscosity, the size effect parameter of corpuscles to the sphere and the wall-condition parameter. Characteristics of steady flows past a sphere are investigated for these parameters. The viscosity ratio represents a polar effect which occurs between corpuscles and the fluid. The size effect parameter means the ratio of a corpuscle to the radius of a sphere.