Summary of Shock Wave Turbulent Boundary Layer Interaction Experiments In a Circular Test Section

Jonathan Sasson; Heath H. Reising; David O. Davis; Paul J. Barnhart

NASA NTRS · 20220017565

Summary of Shock Wave Turbulent Boundary Layer Interaction Experiments In a Circular Test Section

Jonathan Sasson·Heath H. Reising·David O. Davis·Paul J. Barnhart

Abstract

A series of experiments were performed at Mach 2.5 in a 17 cm diameter circular test section to characterize an impinging/reflected shock wave turbulent boundary layer interaction generated by a cone-cylinder centerbody. The cone-cylinder centerbody generates a conical shock wave that interacts with the naturally occurring boundary layer developing on the test section wall. Three different cone angles were used in the experiment to study unseparated, incipiently separated, and separated interactions. When the cone-cylinder centerbody is positioned on the centerline, a flowfield which is two-dimensional in the mean is generated. Three dimensional interactions were also created by offsetting the cone-cylinder centerbody from the test section centerline. The results are intended to provide benchmark quality datasets for computational fluid dynamics (CFD) validation without the pitfalls inherent in rectangular configurations where corner effects prohibit a truly two-dimensional flow in the mean. The experimental measurements included surface flow visualization, wall static pressure, flowfield Pitot tube pressure, constant-voltage anemometry (CVA) normal hot-wire, and particle image velocimetry (PIV) measurements. The hot-wire measurements were used to calculate mean mass flux and total temperature profiles, mass flux and total temperature turbulence intensities, and the mass flux-total temperature correlation. The PIV measurements provide three-dimensional mean velocity measurements. Agreement between the pressure, hot-wire, and PIV measurements is established in the undisturbed upstream flowfield.

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Supersonic shock wave and boundary layer interaction compressible flow

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Jonathan Sasson, Heath H. Reising, David O. Davis, Paul J. Barnhart. Summary of Shock Wave Turbulent Boundary Layer Interaction Experiments In a Circular Test Section. https://ntrs.nasa.gov/citations/20220017565

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