Abstract
This paper aims to investigate the effects of a sound-driven disturbance on a round jet issuing into a counter uniform flow. An annular disturbance was driven by the acoustic excitation and was introduced to the shear layer of the jet at the nozzle exit. Experimental parameters are the velocity ratio Vr of the jet to the counter flow and the Strouhal number of the jet excitation. Fluid dynamical features were examined using LDV with respect to the mean and fluctuating velocity fields along the jet axis. It was found for Vr=1.0 and 2.0 that the annular disturbance slightly changes the decay rate of the mean velocity near the mean stagnation point, but for Vr=3.0 and 4.0 no clear influence of the disturbance was ascertained on the axial mean and rms velocity profiles in the development region of the counter jet.
