Experimental study on effects of plate angle on acoustic waves from supersonic impinging jets

This study experimentally investigates the generation mechanism of a higher-angle lobe which is an acoustic field feature supersonic jet impinging on inclined flat plate. The overall sound pressure level distribution and spectra, conditional averages near schlieren movies, time-averaged wall were obtained for three cases Mach 1.8 ideally expanded jets with plate angles 45°, 22.5°, 10° to downstream axis. In 45° 22.5° cases, appears. dominant waves in are radiated from source region that contains shock suggested be correlated large-scale turbulent structures. These results suggest dominated by generated interaction between inference supported fact near-field wave patterns qualitatively reproduced interference monopoles located neither nor observed case.