Reflection of a Wave at an Interface of Supersonic Flows and Wave Patterns in a Supersonic Compound Jet

Abstract

In the first half of this paper, the behavior of the reflected wave of a weak incident one at an interface of two supersonic flows is studied. The weakness of the incident wave makes it possible to use the isentropic characteristic theory with good approximation and, as a result, complication in the analysis is greatly reduced. It is found in this study that under a certain condition the reflected wave of an incident compression (or expansion) one is an expansion (or compression). The condition is given as a function of the Mach numbers of the flows and the ratios of the specific heats. In the latter half similar treatment is applied to the analysis of wave patterns in a supersonic compound jet. The treatment of the problem in flow deflection and pressure plane simplifies the analysis greatly. It becomes clear in this study that there are two different types of wave pattern in the jet. In the one, pressure is oscillatory in the jet and in the other non-oscillatory. The conditions which discriminate the both cases are also obtained.