Analysis of Pseudo-Shock System Structure and Asymmetry in Laval Nozzles with Parallel Side Walls

Abstract

The scope of this work is to investigate the structure and stochastic asymmetry of pseudo-shock systems in Laval nozzles with parallel side walls in detail by numerical and experimental means. The location of the pseudo-shock system is defined in an adiabatic system of two successive chocked Laval nozzles by the ratio of the critical cross sections A2*/A1*, the stagnation pressure loss across the shock system and viscous losses. Depending on the geometry and the test conditions, the pseudo-shock system attaches stochastically to the upper and lower nozzle wall where the driving mechanism is analysed by means of high speed and short pulse Schlieren visualisation and numerical simulations.