Explosion waves and shock waves VI. The disturbance produced by bursting diaphragms with compressed air

Experimental verification of the theoretical relationships governing the motion of shock waves has been derived from an investigation into the development of the disturbance set up in a uniform tube when a body of compressed gas, confined at one end by means of a copper diaphragm, is released by rupture of the diaphragm. The wave-speed camera has been used to obtain continuous Schlieren records of the passage of these effects along the tube and to analyse their properties under a variety of experim ental conditions, the main variations being those caused by the use of different thicknesses of diaphragm, different lengths of compression and expansion chambers, and of different gases in these chambers. The pressure effects released on the rupture of the diaphragm are the shock wave, a vortex formation and the expanding gases from behind the diaphragm. Schlieren snapshot (spark) photographs have been obtained showing the structure of these pressure effects when they are projected from the end of the tube into free air. The photographs show, in addition to these details, the establishment of a system of stationary sound waves. Diagrams have been constructed based on the experimental data showing the apparent form of the wave during various phases of its progress.