Wall-pressure measurements in a mach 3 shock-wave turbulent boundary layer interaction at a DNS-accessible reynolds number

Experiments are performed to investigate the fluctuating wall pressure in a Mach 2.9 shock-wave turbulent boundary layer interaction with a low Reynolds number based on momentum thickness of 2400. This Reynolds number is accessible to present direct numerical simulations (DNS), so that the data can be used for DNS validation. The configuration studied is a nominally two-dimensional 24° compression corner. Compared to data at higher Reynolds numbers (of order 10⁴-10⁵), the results show a smaller peak in the RMS of the pressure fluctuations. The wall-pressure signal does not exhibit the large degree of intermittency found in the shock-foot region at higher Reynolds numbers. Spectra show that the signal energy is more distributed over the range of shock oscillation frequencies, resulting in a smaller peak energy as compared to data at high Reynolds numbers. The shock motion has a broadband frequency distribution with a peak slightly below 1 kHz, similar to that seen in higher Reynolds number flows. The mean-wall pressure distribution, RMS pressure fluctuation profile, wall-pressure signal, and shock-motion frequency agree well with a DNS performed at matching conditions.