Wall shear stress and pressure fluctuations in compressible turbulent boundary layers laden with particles

We analyze the direct numerical simulation databases of particle-laden compressible turbulent boundary layers to evaluate the influences of the two-way coupling effects on wall shear stress and pressure fluctuations. Via analysis of one-point statistics, frequency spectra, and instantaneous and conditionally averaged flow fields, we demonstrate that increased particle mass loading progressively suppresses wall shear stress fluctuations associated with high-intensity sweeping and ejecting events. Conversely, fluctuations induced by particle feedback forces intensify but remain insufficient to offset the overall reduction in fluctuation intensity. Pressure fluctuations similarly exhibit reduced intensity at higher mass loadings. Notably, the direct influence of particle feedback forces on wall pressure fluctuations is comparatively negligible, indicating that vortical motions dominate wall pressure fluctuations.