Numerical simulation of aerodynamic and aeroacoustic characteristics of subsonic rocket sled

Rocket sled is the main equipment for horizontal launching and ground test equipment for high-speed aircraft. The aerodynamic characteristic analysis of a rocket sled is not only the object of experimental research, but also a way to avoid the potential safety hazard in the ground test which may cause the aircraft to overturn or even get out of its rail. Severe aerodynamic noise may damage the precise instruments during high-speed rocket sleds experiments. In order to instruct the design of aeroacoustics protection, numerical simulations are conducted based on computational fluid dynamics and computational acoustics. The distribution of velocity and pressure has been analyzed. Diagram of sound pressure level on the symmetric face under different situations has been compared. Characteristic frequencies and the directivity of aeroacoustics under three conditions with different Mach numbers are investigated. It can be found that the characteristic frequency and sound pressure level increases with the Mach number of the incoming flow. The directivity of noise at characteristic frequency also changed with the incoming flow's Mach number. Characteristic frequency under three conditions are revealed. Some suggestions have been put forward to reduce the influence of aeroacoustic noise. The conclusions may guide the design of aeroacoustics protection for the rocket sled test.