Detection of fluctuating density gradient flow field in shock wave boundary layer interactions using laser Schlieren system

This paper demonstrates the feasibility of laser Schlieren system in studying unsteady shock motion in important flow phenomena such as shock wave/boundary layer interactions. Time-dependent voltage signals from multichannel measurements reveal important aspects of flow behavior such as amplitude and velocity of shock motion, frequency content, and cross-correlation functions in a very straightforward way. Tests were performed on a Halis axisymmetric configuration in a hypersonic flow with air and CO₂. Received: 8 August 2001 / Accepted: 8 November 2001