Detonation Wave Interactions with Stratified Gas Layers

Simultaneous 2 MHz schlieren and 250 kHz broadband chemiluminescence are used to image the interaction of a hydrogen-oxygen-argon detonation wave in a narrow channel with a hydrogen gas layer. Test results demonstrated the facility capabilities to experimentally study detonations bounded by low-impedance gas. Wave-front velocity as a function of spatial location is extracted from schlieren images. Rapid acceleration of the shock front ahead of the detonating portion of the wave is observed where the hydrogen layer initiates. A porous upper boundary enables rapid decay of the accelerated shock, transitioning after a few cell lengths to a lagging oblique shock. The effects of three different hydrogen layer heights are compared and the resulting impacts on the transmitted shock-detonation complexes are analyzed.