Direct numerical simulation of supersonic turbulent boundary layer with spanwise wall oscillation

Abstract

Direct numerical simulations (DNS) of Mach = 2.9 supersonic turbulent boundary layers with spanwise wall oscillation (SWO) are conducted to investigate the turbulent heat transport mechanism and its relation with the turbulent momentum transport. The turbulent coherent structures are suppressed by SWO and the drag is reduced. Although the velocity and temperature statistics are disturbed by SWO differently, the turbulence transports of momentum and heat are simultaneously suppressed. The Reynolds analogy and the strong Reynolds analogy are also preserved in all the controlled flows, proving the consistent mechanisms of momentum transport and heat transport in the turbulent boundary layer with SWO. Despite the extra dissipation and heat induced by SWO, a net wall heat flux reduction can be achieved with the proper selected SWO parameters. The consistent mechanism of momentum and heat transports supports the application of turbulent drag reduction technologies to wall heat flux controls in high-speed vehicles.