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• A new DDES-Tr, based on the three-equation k-ω-γ transition/turbulence integrated model, was proposed through the similar way with the typical DDES. • A modification of the length scale was introduced to ensure the models worked in their own interest regions. • DDES-Tr model can not only resolve the massive separation on the leeward side, but also model the transition on the windward side. The hypersonic flow at high angle of attack past the Orion capsule was predicted by a delayed detached eddy simulation (DDES), based on a three-equation k-ω-γ transition/turbulence integrated model (Tr). The computational results of the mean and instantaneous heat rates by DDES-Tr are compared with the available measurements and DDES-FT (full turbulence). As expected, the massive separation on the leeward side can be well predicted by both DDES models, but DDES-FT cannot model the transition and over-predicts the heat flux on the windward side. Fortunately, the DDES-Tr model can not only resolve the massive separation on the leeward side, but also model the transition on the windward side. Furthermore, the contributions of the first, second, and crossflow modes on the transition are quantitatively explored. Although the freestream is hypersonic, the second Mack mode is very weak owing to the low supersonic speed after the strong bow shock wave. The transition is mainly dominated by the first and rarely by the crossflow mode. [ABSTRACT FROM AUTHOR]

After considering the local effects of nose bluntness on the transition, a modification for the timescale of the second mode in the three-equation k-ω-γ transition model has been proposed to improve the hypersonic transition past cones. The ratio of local unit Reynolds number over freestream unit Reynolds number ( Re local / Re ∞ ) is introduced to delay and reduce the development of second mode instability, according to the results of linear stability theory. The hypersonic transitions past a cone with three nose radii at the angle of attack of 0° were simulated to calibrate the new model and its constants. Then, the improved model is extended to predict the hypersonic transitions past the cones with larger radius and at non-zero angles of attack. Despite the original model can reflect the transition trend, the improved model performs much better than the original one when comparing with the available measurements. [ABSTRACT FROM AUTHOR]

To predict complex flow, including transition on the windward side and massive separation on the leeward side, a Reynolds averaged Navier Stokes-Large Eddy Simulation (RANS-LES) hybrid model based on the three-equation k - ω - γ transition model (RANS-LES-Tr) was developed. Then, it was applied to simulate the following three cases, such as the low-speed flow past a cylinder only with the first transition mode, the low-speed prolate spheroid flow at a high angle of attack (AoA) with both the first and crossflow modes; and hypersonic flow past the "Orion" capsule with the first, second and crossflow modes. RANS-LES-Tr shows much better agreements with available measurements, such as skin friction and heat flux on the windward side, than RANS-LES based on the full turbulence model. [ABSTRACT FROM AUTHOR]