Viscous Streaming Near an Oscillating and Pulsating Spherical Cavity

Abstract

This paper considers theoretically the viscous streaming from a spherical bubble undergoing small lateral and radial oscillations simultaneously. Assuming the oscillations are of comparable magnitude, it is shown that the radial oscillations greatly enhance the streaming. The form of the flow at large distances is a “Stokeslet”, a steady viscous flow which may however take some time to establish. The sign of the streaming depends on the phase-difference between the two types of oscillation. It should reverse in direction if the phase-difference passes through zero.