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A compressibility correction for the shear stress transport (SST) model suitable for hypersonic compressible turbulent flows is proposed in this paper. Numerical computations are performed by using an improved TVD scheme, and the negative part of the source terms in the turbulence model is discretized by using an implicit scheme. To validate the corrected model, hypersonic flows over a flatplate, as well as compression ramps with or without separated flows are computed by using the developed model. The numerical results reveal that, in comparison with experimental results and results computed by the original model and semi-empirical formulae, the compressibility effects on the SST model stem from the scalar product of the weighted density average of the turbulent fluctuating velocity and the pressure gradient of the average flow field. In addition, it is demonstrated that the presently established model provides more favorable results on the wall pressure, skin friction and wall heating rate distribution for the experiments than the original SST model and other compressibility modifications. [ABSTRACT FROM AUTHOR]

Shock/boundary' layer interaction often exists in hypersonic inlets. Thus, a new method based on deformable bump to control boundary layer separation is brought forward in this paper. Computational results indicate that the method is effective to control shock/boundary-layer interaction by means of the precompression effect at windward side of the bump, the weakening effect on reflected shock and the accelerating effect on the boundary layer flow of expansion wave. When the shock impingement position is near the expansion wave-generated area at leeward side of the bump, the size of the separation bubble is greatly reduced. Furthermore, the control effect can be enhanced by increasing the bump height within the proper range. However, excessive height of the bump can strengthen the induced compression and expansion waves thus bringing negative effect on the inlet. In addition, the curvature of concave region at the bump windward side should be small and the largest curvature point in the expansion wave-generated area should be close to the shock impingement position while the curvatures of concave and prominent regions at the bump leeward side should be approximately equal. [ABSTRACT FROM AUTHOR]