Peculiarities of transonic inviscid flow over a concave airfoil

A numerical simulation of inviscid transonic flow over concave airfoil was carried out. Surface showing dependence of lift coefficient on freestream Mach number and angle of attack has been plotted based on experimental results. Has been found that this surface has a gap when angle of attack exceeds some critical angle, so there could be lift coefficient jumps for some values of freestream Mach number.