NUMERICAL INVESTIGATIONS ON SUPERSONIC FLUID FLOW BEHAVIORS PAST A CAVITY CONCERNING VELOCITY FIELD AND AEROACOUSTIC INFLUENCES WITH LES-APPROACH

Abstract

A suitable numerical model is developed to predict supersonic flow pertaining to a 3D open cavity. The researches of supersonic flow over the 3D cavity having length-to-depth ratio of 2, include the supersonic free-stream Mach number of 2 and the flow Reynolds number of 105. The numerical simulation has been done with the Large Eddy Simulation (LES) approach. The Smagorinky model is introduced for the present investigation. The results found have been compared with the numerical simulation predictions available in the literature. The results have been expressed in the form of both coefficient of pressure (Cp) and overall sound pressure level (OASPL) along the side wall of the open cavity. The coefficient of pressure along the side wall of the said cavity appears to be very much comparable both qualitatively and quantitatively with the reported numerical results by the other investigator. Nevertheless, the overall sound pressure level along the side wall of the stated cavity is over-predicted by nearly 25-40 dB between the aft and front walls. Above and beyond, the velocity vector pertaining to the open cavity has also been investigated. Fairly large recirculation is witnessed inside the cavity and therefore these need to be supressed. Besides, the amalgamation of a spoiler is also planned for future to alter the flow structures inside the cavity which can bring about the reduction in recirculation in addition to the overall sound pressure level along the side wall of the open cavity.