Tracer-based Shock Visualisation in a Transonic Compressor

Abstract

Tracer-based shock visualisation (TSV) is a new optical non intrusive technique to visualise the position and the structure of shocks in a transonic axial compressor. The number per volume density of particles, which are added to the flow, and with it the density of the fluid are visualised with a laser light sheet and an intensified CCD Camera. Structures like normal and oblique shocks, folk-shocks and separation regions can be clearly identified. The 3D-shape and structure of the blade passage shock is reconstructed from the collected data. The results are in good agreement with wall pressure measurements and numerical data. The experimental difficulties of the technique are discussed.