Analysis of irregular Mach reflections of explosively-driven shock waves from surfaces

When shock waves reflect from surfaces at angles of attack, the reflection generated can be classified as either a regular oblique or an irregular Mach reflection. Mach reflections contain a normal shock, the Mach stem, that forms to allow conservation of mass, and results in a significant increase in pressure compared to an oblique shock wave reflection. Shock polar analysis is used to identify the regions of Mach number and angle combinations that will result in the formation of irregular shock reflections. The structure of several irregular reflections is analyzed to estimate the peak overpressure and other characteristics for each type of reflection. A developed analytical model of shock reflections is then used to determine the reflection type and characteristics from varying height of burst from a scaled explosive weight. This approach can be used to analytically determine and optimize the overpressure generated by explosively driven shock waves produced at varying heights of burst.