CKDO one-equation RANS simulation on transition of hypersonic cross flow

Hypersonic cross-flow transition problem contains turbulence-shock effects, compressibility, cross-flow, transition, and many other phenomenons. This work employs the CKDO-tran model to simulate HIFiRE-5 which is a canonical model for hypersonic cross-flow transition. The compressibility effect, Reynolds number effectand attack angle effectare studied. It is found that the KDO-tran model without considering the compressibility effect cannot give an accurate prediction on transition, while it can predict the hypersonic cross-flow transition at different Reynolds number conditions, without introducing a specific transition mechanism. When the angle of attack is 0°, CKDO-tran can better predict the transition image of the two lobes; when the angle of attack is 4°, the transition line yielded by CKDO-tran starts too early, but the transition pattern is similar to the measurements. Therefore, CKDO-tran model is promising and deserves further development. The sensitivity study of inflow turbulence intensity shows that, along with the decrement of inflow turbulence intensity, the predicted transition pattern gradually deviates from the true pattern for the 4° attack angle case. Finally, the attack angle effect is analyzed, and it is speculated that accurate modeling of the freestream turbulence-shock interaction is the key to eliminate the attack angle effect.