Predicting crossflow induced transition with laminar kinetic energy transition model

• Published in: The International journal of heat and fluid flow 2020-02, Vol.81, p.108522, Article 108522
• Main Authors: Qin, Yupei, Yu, Xin
• Format: Article
• Language: English
• Subjects: Boundary layer transition; Crossflow; Hypersonic; Laminar kinetic energy
• ISSN: 0142-727X; 1879-2278
• DOI: 10.1016/j.ijheatfluidflow.2019.108522

lPrediction for crossflow induced transition is achieved via extending kT-kL-ω model.lTimescale and crossflow limit function are constructed to incorprate crossflow effect.lComputaional results shows remarkble agreement with experiment data or DNS data. The hypersonic laminar kinetic energy transition model is developed to be appropriate for crossflow induced boundary layer transition prediction. A crossflow timescale is constructed and incorporated in the kT-kL-ω transition model to reflect crossflow effect during three-dimensional boundary layer transition. The stream-wise vorticity is selected as the indicator of crossflow strength. Regarding the inviscid unstable characteristic of crossflow instability, the crossflow timescale is constructed by reference to the second mode timescale. To eliminate inappropriate development of the crossflow timescale where the effective length scale is large enough while the crossflow strength remains at a quite low level, a crossflow velocity limit function is proposed. The revised kT-kL-ω transition model has been applied to HIFiRE-5 and blunt cone with 1°angle of attack test cases. Results show good correspondence with the experimental data and DNS data, which demonstrates that the constructed crossflow timescale makes the revised transition model capable of reproducing crossflow induced transition behavior with a reasonable degree of accuracy.