Two-dimensional axisymmetric simulation of under-expanded supersonic impinging jet

Abstract

This paper investigates the unsteady flow features of two-dimensional (2D) axisymmetric under-expanded supersonic impinging jet with a nozzle pressure ratio (NPR) of 3.5 and a distance ratio (z/D) of 2.5. A comparison between 2D axisymmetric, three-dimensional (3D) Large Eddy Simulation (LES) and experimental data is given. Good agreement can be seen in mean profiles and shock location data. Utilizing spectral and Proper Orthogonal Decomposition (POD) tools, two acoustic contributions of the 2D axisymmetric simulation are observed at the dominant tone frequency. The first one is responsible for acoustic waves propagating to the far field and the other one observed from the sides of the jet p..