Navier-Stokes study of supersonic cavity flowfield with passive control

A computational investigation of the supersonic turbulent flow past a two-dimensiona l rectangular cavity with passive venting is described. The effect of passive venting was included through the use of a porous surface over a vent chamber in the floor of the cavity. The passive venting was numerically simulated by the use of a linear form of the Darcy pressure-velocity law. The time-accurate solutions of the two-dimensional, Reynoldsaveraged, Navier-Stokes equations were generated using the explicit MacCormack scheme. The capability Of the numerical scheme is first demonstrated by the computations of an open and closed cavity without passive venting. The results of these computations also provide a reference case for the passive venting computations. The effect of passive venting on the closed cavity is then demonstrated and analyzed. These results show that the passive venting dramatically changes the closed cavity flow to nearly an open cavity flow. The free shear layer formed between the high-speed outer flow and slower inner flow is seen to bridge the cavity completely j resulting in an open cavity flow. The passive venting velocities are determined to be less than 5% of the freestream velocities, and largely confined to the upstream and downstream portions of the cavity floor. The computational results show good agreement with available experimental data.