Shock wave instability and spontaneous acoustic emission for arbitrary disturbances in real gases

The reflection of post-shock acoustic waves off the shock front is considered, and shock wave stability criteria are derived from considerations of the behavior of the reflection coefficient. The predictions compare well with observations of shock wave instability in carbon dioxide. However, extensions to the model seem necessary to give correlation in ionizing argon. Proposals are made for the possibility of unstable shock waves in liquefaction and detonation experiments, but these have not yet been tested experimentally.