Numerical study of the Guderley and Vasilev reflections in steady two-dimensional shallow water flow

We present high-resolution numerical solutions of the depth-averaged two-dimensional inviscid shallow water equations which provide new information on shock reflection configuration within the von Neumann paradox conditions. The computed flow field and shock wave patterns close to the triple point for the Guderley and the Vasilev reflections confirm the four-wave theory. We suggest that the most likely Guderley reflection model is a four-wave pattern with a compression wave that originates along the downstream boundary of the supercritical patch. The compression wave, after being refracted by the slip stream, turns the flow behind the Guderley stem further toward the wall until critical condition is achieved.