Correction of sensor-size-related attenuation for wall pressure fluctuations measurements

Abstract

The paper presents the correction of sensor-size-related attenuation for wall pressure fluctuations measurements beneath turbulent boundary layer flows. The wall pressure spectra were measured with three commonly used flush-mounted sensors with protection screens, one flush-mounted surface sensor, and one pinhole-mounted sensor that measured the unattenuated spectra as reference. Zero, favorable and adverse pressure gradient flows were realized on a flat plate model, where the pressure gradients were produced by a NACA 0012 airfoil installed above the plate. The flows cover the Reynolds number in the range of 2200 < Re θ < 9100 and the boundary layer shape factor of 1.3 < H < 1.85. The Hu model is applied to correct the attenuation measured with the flush-mounted sensors. Convincing correction results are obtained for all the sensors and flow conditions.