Abstract: A transition model considering the compressibility of flow, which is called γ-Reθt-fRe, is developed from the original γ-Reθt transition model framework. The compressibility correction is introduced for the existing transition criteria, and the original transition correlation function based on incompressible flow is modified by using the Reynolds number compressibility analogy relation obtained by reference temperature method. In order to achieve the localization of the model, an addition-al Reynolds number compressibility analogy relation fRe transport equation is constructed. The developed γ-Reθt-fRe transition model is used to examine the transition cases under different flow conditions and compared with the basic γ-Reθt transition model. The numerical simulation results show that the γ-Reθt-fRe transition model achieves seamless unified simulation capability from low speed to high speed. Under the condition of low speed flow, γ-Reθt-fRe transition model is automatically restored to the basic γ-Reθt transition model. Under supersonic and hypersonic flow conditions, γ-Reθt-fRe transition model significantly improves the prediction of flow transition trigger position and transition zone development.

Key words: Flow transition, Hypersonic, γ-Reθt transition model, Reference temperature method, Compressibility correction