Modulation of a Quantized Vortex Street with a Vibrating Obstacle

Dynamics of a superfluid flow past an obstacle are investigated by solving the Gross–Pitaevskii equation numerically. For appropriate velocity and size of the obstacle, quantized vortices are periodically generated in the wake, which form a Bénard–von Kármán vortex street. It is found that vibration of an obstacle modulates the vortex street, breaking a symmetry. The parameter dependence of the modulation dynamics of vortices is investigated.