In this paper, the problem of concentric pervious spheres carrying a fluid sink at their centre and rotating slowly with different uniform angular velocities Ω1. Ω2 about a diameter has been studied. The analysis reveals that only azimuthal component of velocity exists and the torque, rate of dissipated energy is found analytically in the present situation. The expression of torque on inner sphere rotating slowly with uniform angular velocity Ω1, while outer sphere also rotates slowly with uniform angular velocity Ω2, is evaluated. The special cases like, (i) inner sphere is fixed (i.e. Ω1 = 0), while outer sphere rotates with uniform angular velocity Ω2, (ii) outer sphere is fixed (i.e. Ω2 = 0), while inner sphere rotates with uniform angular velocity Ω1, (iii.) inner sphere rotates with uniform angular velocity Ω1, while outer rotates at infinity with angular velocity Ω2; have been deduced. The corresponding variation of torque with respect to sink parameter has been shown via figures. AMS subject classification – 76 D07.

}, type={ArtykuĹ‚y / Articles}, title={Stokes flow around slowly rotating concentric pervious spheres}, volume={vol. 60}, number={No 2}, pages={165-184}, journal={Archive of Mechanical Engineering}, publisher={Polish Academy of Sciences, Committee on Machine Building}, doi={10.2478/meceng-2013-0011}, keywords={rotation of concentric spheres, fluid sink, slow viscous flow, Stokes approximation}, }