Flow turbulization in a pseudo-shock forming in an axisymmetric duct with a frontal inlet

The results of the numerical modeling of the supersonic flow in an axisymmetric duct in which a pseudo-shock arises are presented. The duct includes the frontal inlet with a funnel-shaped part of initial compression of the supersonic flow and with a cylindrical throat part as well as the subsequent (cylindrical or diverging) diffuser where the flow slows down to a subsonic velocity. The flow conditions at the freestream Mach number M = 6 have been considered. Numerical computations of the flow have been done using a Navier–Stokes equations code and the k-ω SST turbulence model. As a result of computations, such flow parameters have been determined as the location of the pseudo-shock beginning, the length of the pseudo-shock supersonic part, the pressure distribution on the duct wall, the total pressure losses as well as the characteristics of flow turbulence. In particular, the variation of the turbulence intensity and turbulent viscosity along the pseudo-shock length have been examined and, based on these characteristics, the possibility of determining the location of a cross section, in which the pseudo-shock can be treated as completed, have been considered.