Synchronous Surface Pressure and Velocity Measurements of standard model in hypersonic flow

Abstract

Experiments in the Hypersonic Wind tunnel of NUAA(NHW) present synchronous measurements of bow shockwave and surface pressure of a standard blunt rotary model (AGARD HB-2), which was carried out in order to measure the Mach-5-flow above a blunt body by PIV (Particle Image Velocimetry) as well as unsteady pressure around the rotary body. Titanium dioxide (Al2O3) Nano particles were seeded into the flow by a tailor-made container. With meticulous care designed optical path, the laser was guided into the vacuum experimental section. The transient pressure was obtained around model by using fast-responding pressure-sensitive paint (PSP)sprayed on the model. All the experimental facilities were controlled by Series Pulse Generator to ensure that the data was time related. The PIV measurements of velocities in front of the detached bow shock agreed very well with the calculated value, with less than 3% difference compared to Pitot-pressure recordings. The velocity gradient contour described in accord with the detached bow shock that showed on schlieren. The PSP results presented good agreement with the reference data from previous studies. Our work involving studies of synchronous shock-wave and pressure measurements proved to be encouraging.