Experimental Investigation of the Acoustic Characteristics of Shock-Vortex Ring Interaction Process

Abstract

The acoustic waves generated during the interaction of shock wave with a compressible vortex ring are studied experimentally. All experiments are performed in a short driver section shock tube with helium as a driver section gas for shock Mach numbers 1.30, and 1.55. The effect of different shock Mach numbers and reflected shock strength on the generation of acoustics waves is studied for different ring velocities. The far field noise generated during the interaction of the shock wave with the vortex ring is identified in addition to the sound generated during the evolution of vortex rings using Discrete Wavelet Transform. It has been found that the intensity of acoustic disturbance generated during the interaction of vortex ring with shock is dominant as compared with the sound generated during other key processes such as formation, jet interaction and pinching off noise. The intensity of acoustic fluctuation by shock vortex interaction is dominant in the direction of shock wave which also increases with Mach numbers.