Shock tubes

Abstract

A shock tube is a facility that can produce transmitted shock waves in controlled laboratory conditions. The facility is a duct divided into two sections as shown schematically in Fig. 1. One part, the driver, accommodates high pressure gas (P4) while the other section (the driven) contains the low pressure test gas (P1). The two sections are separated by a barrier (diaphragm). Once the barrier is suddenly removed a shock wave propagates into the driven section and a rarefaction wave propagates into the driver section. By appropriate choice of the two pressures, P4 and P1, and gas species a desired strength of the resulting/generated shock wave (its Mach number, Ms) can be obtained. As shown subsequently, the initial thermodynamic conditions of the gases used dictate the post-shock flow i.e., the conditions behind the shock wave.