OSCILLATION PHENOMENA OF PSEUDO-SHOCK WAVES.

Abstract

The oscillation phenomena of pseudo-shocks in a straight pipe were experimentally investigated and the causes and the frequencies of oscillations were discussed. As the result, it was found that the oscillation of the pseudo-shock became stronger with the increasing Mach number and the maximum wall static pressure fluctuation induced by the oscillation amounted to about 60 percent of the difference of static pressures before and behind the shock. Morevoer, it was shown that this oscillating phenomena could be explained by the interaction of the shock with the small disturbances existing in the supersonic flow upstream of the shock.