Numerical Simulation of Supersonic Jet Noise with Overset Grid Techniques

Supersonic jets with a complex shock pattern appear in numerous technical applications. Most supersonic jets, especially in modern military or civil aircraft, are not perfectly expanded. Thereby, shocks are appearing in the jet core and interacting with the turbulent mixing-layers and emanating shock induced noise. Under certain conditions this upstream traveling noise can be amplified due to a closed feedback loop. These so called screech tones can reach sound pressure levels of up to 160 dB [11] and hence lead to immense noise pollution and even structural fatigue.