Navier-Stokes Computations of Turbulent Compressible Two-Dimensional Impinging Jet Flowfields

Abstract

Planar mass-averaged compressible Navier-Stokes and energy equations in stream function/vorticity form are solved in conjunction with a two-equation (fc-e) turbulence model for impinging jet configurations relevant to VTOL aircraft design. The physical domain of the flow is mapped conformally into a rectangular computational region. An augmented central-difference scheme is used to preserve the diagonal dominance character of the difference equations at high Reynolds numbers. The resulting difference equations are solved by successive point relaxation. Excellent agreement with the experimental data is obtained for the airframe undersurface pressure, ground-plane pressure, and the centerline velocity decay along the jet axis. Computed turbulent kinetic energy along the jet axis, however, has a larger overshoot near the ground plane than indicated by the experimental data.