Numerical research on aerodynamic characteristics of cavity with store at supersonic speeds

The aerodynamic characteristics of cavity with store at supersonic speeds are researched using large eddy simulation (LES) method and FW-H equations. A computational model is established, and the grid reliability is proved. The results show that the flow field is separated into three independent vortices because of the existence of missile, and the fluctuation of static pressure coefficient is enhanced. The sound pressure level (SPL) of cavity with store is 5~6 dB lower than that of empty cavity. The max SPLs are on both the sides of the cavity aft-wall, and the peak frequency is below 200 Hz. Flow field sound is generated from the self-sustained oscillation of shear layer. The sound generation cycle is shed vortices-sound wave-reflection sound wave-new shed vortices, which exists in the area between the head of missile and the aft-wall of cavity. These results can be used to build the control method for flow field of cavity with store at supersonic speeds.