Entrainment of Self-Sustained Flow Oscillations: Phaselocking or Asynchronous Quenching?

Abstract

Asynchronous quenching and phaselocking are two different mechanisms leading to the onset of synchronization of flow instabilities with externally excited oscillations. Experimental evidence for asynchronous quenching as well as for phaselocking is given from response measurements of representative pressures, velocities, or of forces for the following types of flow - forcing interactions: an oscillating circular cylinder in crossflow; interaction of an unstable, planar jet with an oscillating leading edge; a forced mixing layer between parallel streams; and a thermally forced cavity shear-layer.