The effect of boundary conditions on the fluid motion induced by the rotational-oscillatory motion of a porous sphere

Background. The theory of fluid motion through porous media is being investigated intensively in the present time due to its vast applications. The motion of fluid in its volume essentially depends upon boundary conditions on media interfaces. The present paper considers the effect of boundary conditions on the fluid flow induced by the rotational-oscillatory motion of a porous sphere submerged in the fluid. Materials and methods. The methods of mathematical physics and vector analysis were applied to solve the problem. The numerical methods were used in construction of velocity profile graphs. Results. The fluid velocity fields inside and outside of a porous sphere were determined depending on the boundary conditions on its surface. The velocity profiles are presented on the graphs. Conclusions. It is shown that the boundary conditions form has an effect on the fluid motion inside and outside of the porous sphere. Inside and outside the porous sphere there are surfaces on which the velocity equals zero. In the gaps between those surfaces the liquid flows with velocities pairwise opposite in directions.