FLOW DUE TO A POINT VORTEX IN AN OSCILLATING AND ROTATING STRAINING FLOW

摘要

We consider a simple model of transport of a passive scalar around a coherent vortex at distances much larger than its size but much smaller than the distance to its nearest neighbours. The vortex is approximated by a point vortex with circulation F, the strain rate has harmonic time-dependence, and the principal axes rotate with constant angular velocity.