Secondary Flow Induced between Oscillating Circular Cylinders

The two-dimensional flow between oscillating circular cylinders is theoretically analyzed. The outer cylinder performs rotatory oscillations and the inner cylinder performs translational oscillations with small amplitude. Particular attention is focused upon a steady secondary streaming owing to the nonlinear hydrodynamic effect. The analytical expression for the secondary streaming is obtained. Streamlines of the secondary streaming are shown for a couple of values of radii of two oscillating circular cylinders. The behavior of the steady secondary streaming induced between two cylinders is clarified.