Abstract: This paper presented a numerical simulation method of three-dimensional shock wave/turbulent boundary layer interaction generated by a 20-deg sharp fin mounted on a flat plate at Mach number 2.93 and Reynolds number 9.8×10⁵,based on incoming boundary layer thickness.This investigation was conducted based upon GAO-YONG compressible turbulence equations recently developed by GAO Ge and YONG Yan.The equations were discretized using a finite volume method with the convection terms and diffusion terms calculated by the third-order Roe's flux difference splitting scheme and the second-order central difference scheme,respectively.The Runge-Kutta time marching method was employed to solve the governing equations for steady state solutions.Numerical results were compared with available experimental data in the form of surface pressures and boundary layer surveys of yaw angles.The computed three-dimensional flowfield shows most of the features covering λ-structure shock wave,primary vortex,separation region,and high-speed jet impingement;meanwhile,quasi-conical behavior of the surface pressure,surface attachment and separation streamlines exhibited in quasi-conical flowfield model of Alvi and Settles are presented.