Resonancet Effect in Jet Screech Mechanism

Abstract

Acoustic emission from an under-expanded supersonic jet has a spectrum that contains remarkable discrete tones which is called jet screech. Though a lot of researches have been carried out concerning the mechanism of jet screech, still many questions about some issues such as discontinuous jump of screech frequency, amplitude prediction of screech tone and source location of jet screech remain unsolved. For a physical understanding of jet screech mechanism and role of shock waves in generation jet screech, a kind of resonance system has been introduced and the mechanism of jet screech has been explained by the sound -disturbance resonance model.