Visualization of Self Induced Flow Oscillation in an Underexpanded Sonic Jet

Abstract

Self induced flow oscillation occurs when an underexpanded sonic or supersonic jet impinges on an obstacle. This oscillatory flow involves the movements of the Mach disk and pressure oscillation on the obstacle. In the present paper, a numerical simulation is carried out on a sonic jet impinging on a cylindrical body with the same diameter as the exit diameter of a nozzle. The flow field with the oscillation is visualized using computer color graphics and refer to a locus of the Mach disk and pressure disturbances of the wall surface on a cylindrical body.