Abstract
The unsteady rarefaction wave generated in the double diaphragm shock tunnel by rupturing a light diaphragm placed between the vacuum and the test gas sections has been investigated experimentally. The diaphragm motion has been visualized by a sequence of Schlieren photographs. This has been found to be useful in order to locate the path of the diaphragm fragments after the bursting within the rarefaction wave in the (x-t) diagram. It has been concluded that at Mach number equals 4.25 the light diaphragm does not tear off, while at Mach number equals 7, it has been torn to fragments due to the impact of the primary shock wave and the higher temperature. The data reduction agrees well with the emission-absorption measurements.
