Unsteady Flow between Two Concentric Rotating Spheres along with Uniform Transpiration

In this study, the numerical solution of unsteady flow between two concentric rotating spheres with suction and blowing at their boundaries is presented. The spheres are rotating about a common axis of rotation while their angular velocities are constant. The Navier-Stokes equations are solved by employing the finite difference method and implicit scheme. The resulting flow patterns are presented for various values of the flow parameters including rotational Reynolds number Re , and a blowing/suction Reynolds number Rew . Viscous torques at the inner and the outer spheres are calculated, too. It is seen that increasing the amount of suction and blowing decrease the size of eddies generated in the annulus.

Authors:

• O. Mahian
• A. B. Rahimi
• A. Kianifar
• A. Jabari Moghadam

Keywords:

• Concentric spheres
• numerical study
• suction andblowing
• unsteady flow
• viscous torque.

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