Shock-associated noise in supersonic jets

This paper examines the fundamental mechanism of broadband shock noise in an improperly expanded supersonic jet. The study includes circular convergent and convergent-divergent nozzles. The main source of shock noise is determined to be the transient interaction between the shock front and the convected vorticity within the jet plume. The discussion of the noise generation mechanism is based on detailed numerical analysis, theoretical modeling, refined measurements of the jet mean flow, shock-cell structure, turbulence, and noise. Results in this study provide a broad-based generalization for the Harper-Bourne and Fisher analysis and prediction method.