With the continuous development of computer systems, numerical simulations have been applied to complex flow fields for the engineering purposes. The flow in a scramjet combustor is typical one of such flow fields. We have studied the supersonic turbulent flow field numerically, and made it clear that existing turbulence models overestimate the turbulent intensity in the flow field. In the work, we concluded that, in order to correct the overestimation, some kinds of compressible effects should be reflected in a turbulence model. In addition, we examined the model performance for the flow passing through a shock wave, using the data derived from the liner interaction analysis. It was found that no existing turbulence model can reproduce the turbulence behavior around a shock reasonably, and the grid dependence is always very severe. In the present study, we propose a k-ε model capable of accurately reproducing the turbulence amplification due to a shock without grid dependence of solutions. Moreover, the proposed model is applied to the modeled flow in a scramjet combustor for the purpose of extensive validation. The results show that the turbulence amplification due to the shock is suppressed by the present model, and the smaller turbulence intensity is predicted in the region behind the shocks. These facts suggest that our model is promising for the computation of combustion, because the phenomena of self-ignition and non-premixed turbulent diffusing flame depend largely on the turbulence intensity.
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