Implicit flux-split schemes for the Euler equations

PROGRESS in the development of implicit algorithms for the Euler equations using the flux vector splitting method is described. Comparisons of the relative efficiency of relaxation and spatially split, approximately factored methods on a vector processor for transonic and supersonic twodimensional channel flows are made. A hybrid threedimensional algorithm is developed that uses relaxation in one coordinate direction and approximate factorization in the crossflow plane. The scheme is completely vectorizable and recovers conventional space-marching schemes for fully supersonic flows. The method is applied to a forebody shape in supersonic flow with an embedded pocket of subsonic flow.