The History of the Study of Shock Wave's Mach Reflection from the Wedge

This article discusses the history of study of shock-wave structures arising at a clash of the shock wave on a wedge. We introduce the concept of regular and Mach reflection. We consider von Neumann three-wave model containing a branching shock wave, main and reflected discontinuities, a tangential discontinuity (sliding surface) behind the shock waves line of intersection. Experiments on studying Mach reflection at low Mach numbers and small angle of the wedge are described. The main works devoted to J. Neumann paradox when at low Mach number Mach reflection, in accordance with the theory, cannot exist, but, nevertheless, is observed in the experiments. The work is useful for engineers and scientists to compile a basic overview of the problem of Mach reflection.