Spatial Characteristics of Turbulent Kinetic Energy Transfer in Supersonic Compression Corners

Direct numerical simulations (DNSs) were performed to study the shock-wave/turbulent-boundary-layer interaction (SWTBLI) in compression corner flow with turning angle 8° and 24°. The freestream Mach number was Ma_∞ = 2.9. The spatially developing characteristics of turbulent kinetic energy (TKE) transfer were analyzed in both physical and scale space to delineate nonlocal nonequilibrium characteristics of multiscale TKE transfer. It is found that turbulent amplification occurs after the shock wave. Such a phenomenon is attributed to the enhancement of the TKE production that leads to the spontaneous spawn of outer-layer large-scale turbulent motion. If the turbulent boundary layer (TBL) separates from the wall after the shock wave (in the 24° case), the outer layer is approximately decoupled from the inner layer, resulting in a quasi-equilibrium TKE transfer process; meanwhile, the inner-layer TKE transfer process reappears, leading to a spatial developing two-layer feature. In contrast, if no mean TBL separation is evident (in the 8° case), the TKE transfer process in both the inner-layer and outer-layer regions gets enhanced in the SWTBLI region. Furthermore, the kinematic self-similarity in the inertial region of the attached Turbulent boundary layer (TBL) is broken after the shock wave, indicating the significant influence of SWTBLI on turbulent eddies.