Drag on an axisymmetric body performing rectilinear oscillations in a micropolar fluid

Abstract

In this paper, a general formula for the drag experienced by an axisymmetric body oscillating rectilinearly along its axis of symmetry in an incompressible micropolar fluid which is otherwise at rest is derived. The oscillatory flow of an incompressible micropolar fluid arising from the harmonic oscillations of an approximate sphere along its axis of symmetry is also considered. Assuming that the oscillation amplitude is small, the velocity components are obtained in terms of Bessel functions and Gegenbauer's functions. The drag experienced by the body is evaluated by using the formula derived and its variation is studied with respect to micropolarity parameter, frequency parameter and geometric parameter. The oscillatory flow generated by the sphere and spheroid are obtained as special cases.