Recent advances in the shock wave/boundary layer interaction and its control in internal and external flows

High-resolution direct numerical simulations of flow structure and aerodynamic performance of wind turbine airfoil at wide range of Reynolds numbers

“…The flow recirculation and separation bubbles are observed on the suction surface, which then drop from the aerofoil surface and leave from the trailing edge adding more turbulence to the flow. A significant difference between the two Reynolds numbers is observed at α=16 o as the flow separation at this angle is remarkably small when the Reynolds number is increased to 1.5×10 5 . For a given adverse pressure gradient distribution, the separation resistance of the turbulent boundary layer increases with increasing Reynolds number.…”

“…The area that has recirculation flows and vortex generations is generally called Separation Bubble [5]. Koca et al [6] experimentally investigated the vortex generation over NACA-4412 wind turbine airfoil.…”

“…Kamada et al [10] used oil-film method, and blade surface tufts to visualise the flow structure over horizonal-axis wind turbine airfoils. The Separation bubbles were presented for the case of turbulent intensity (TI)=0.20% and Re=2.0×10 5 . The experiments showed that when the angle of attack increased, the separated region and vortex generations become larger and noticeable.…”

“…D'Alessandro et al [14] used Large eddy simulations (LES) to predict the flow structure and control the separation over dimpled wind turbine blade with NACA 64-014A airfoil. The simulations were performed at Re=1.75×10 5 . They found that the dimples produce a reduction of the LSB extension if the dimples were positioned before the LSB.…”

Hypersonic flow control of shock wave/turbulent boundary layer interactions using magnetohydrodynamic plasma actuators

“…As hypersonic vehicles become able to reach higher Mach numbers (Ma) in the relatively lower layers of near space, the shock wave/turbulent boundary layer interaction (STBLI) of internal and external aerodynamics become more obvious (Zhang et al, 2019;Huang et al, 2020). Oblique STBLI is a typical configuration for the intake of hypersonic vehicles; this means that the strong adverse pressure gradient brought about by the compression wave system of intake causes the boundary layer to separate and generate complex and unsteady wave systems.…”