A 2D modelling of an unsteady supersonic flow (M=3) in a channel with a parabolic arc obstacle (left Figure) and with a step (right Figure). The Euler equations for ideal compressible gas are in use. The pictures show adaptive moving grid which is used to catch moving shock waves. The numerical scheme implements quasi-second order predictor-corrector method with antidiffusion near strong discontinuities like shock waves (Code ASTRA, 2001).