Turbulent Shock-Wave/Boundary-Layer Interactions Without Sidewall Effects at Mach 2.5, 3.0, and 3.5 — PIV Measurements from 2024 Test Entry

The High-Mach Validation Experiments (HMVE) campaign was initiated as a follow-on to shock-wave/boundary-layer interaction (SWBLI) experiments previously completed in the NASA GRC 225 cm2 Wind Tunnel at a freestream Mach number of 2.5. Data were collected at Mach 3.0 and 3.5 freestream conditions using the same set of 3 angles for the conical shock generators in the axisymmetric test section. Select cases from Mach 2.5 testing were also duplicated to verify repeatability. Particle image velocimetry (PIV) measurements were applied to collect large ensembles of velocity data which were stitched together to form a quasi-continuous view of the mean and turbulent flowfield behavior. Densely-spaced wall pressure measurements were concurrently acquired to supplement the flowfield information from PIV. The primary purpose of this report is to assess the quality of data obtained in this entry to guide subsequent test entries after which the comprehensive results will be analyzed in-depth. Herein, velocity data is visualized component-by-component in
contour plot form to visually assess the ability of the PIV technique to capture detailed flow features and also used to quantify and correct for small displacements in the shock generator tip which occur due to the long cantilevered support. As the Mach number regime contained in the overall dataset is being expanded, results are presented in a fashion which highlights trends in the flowfield behavior with variation in that parameter.