Supersonic particle-laden turbulent boundary layers (TBLs) over a flat-to-concave surface at Mach 2.7 were investigated for the first time using Eulerian-Lagrangian simulations. In the transition section, the concave surface's compressible effect creates a high-frequency collision zone and significantly increases the particle volume fraction. In the downstream concave section, Görtler-like vortices induced by concave surface dominate particle dynamics. Particles are transported from the outer to the inner TBL along interregions of Görtler-like vortices, while being entrained in large-scale low-speed regions and ejected from the inner to the outer TBL. Görtler-like vortices enhance particle preferential accumulation and increase particle mass exchange of high- and low-speed fluids, particularly for large inertial particles (${\text{St}}^{+}=75$). This leads to a decrease in Reynolds shear stress and an increase in skin friction due to concentrated drag feedback. In contrast, small inertial particles (${\text{St}}^{+}=15$) distribute uniformly and have minimal impact on turbulence due to their better flow tracking in the concave section. Additionally, the concave geometry enhances pressure gradients and drag forces, thickens the viscous sublayer, and drives particles toward the intrados, which significantly reduces particle-wall collisions and deposition in the wall.

Close

PrevNext

View figure in article

• Compressible flows
• Turbulent multiphase flows