To the Problem of Friction Minimization on Permeable Surfaces at Supersonic Flow Rate

In this paper, we consider the variational problem of minimizing the Newtonian drag on an airfoil in a supersonic gas flow. A new condition for Lagrange multipliers on the streamlined airfoil was found that can be used to construct an optimal law for injection control in the analytical form. It is shown that for the flow around wedges, this control is finite at the stagnation point that is important in terms of practical realization of the optimal control.