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对原始的k-ω-γ转捩模式和“层流+转捩准则”模型进行了改进,在2种方法中分别增加了横流模态时间尺度和横流转捩准则用于预测横流失稳诱导转捩。通过对网格预处理可并行计算获得边界层外缘信息以及边界层内横流速度。采用不同雷诺数条件下的0°攻角尖锥以及HIFiRE-5外形对2种方法预测高超声速边界层转捩的性能进行了比较分析。研究结果表明,2种方法均能正确反映高超声速边界层转捩起始位置和转捩区长度随雷诺数的变化趋势,但不能捕捉转捩区热流峰值;“层流+转捩准则”模型计算得到的传热系数在全湍流区较k-ω-γ转捩模式偏高。对于同时存在流向不稳定和横流不稳定的HIFiRE-5外形,改进的k-ω-γ转捩模式和改进的“层流+转捩准则”模型相比于原始的模型均能更加准确地预测中心线两侧横流失稳诱导形成的转捩;对于中心线附近因速度剖面拐点引起的边界层转捩,“层流+转捩准则”模型由于与边界层厚度相关,预测得到的转捩位置较试验结果靠前,k-ω-γ转捩模式与试验结果吻合很好。
The original k-ω-γ transition model and the “laminar + transition criterion” model were improved, and the cross-flow modal time scale and cross-flow transition criterion were added to the two methods respectively to predict the cross-flow loss Steady induction transfer 捩. The boundary information and the cross-flow velocity in the boundary layer can be obtained by parallel computing of grid preprocessing. The performance of two methods for predicting hypersonic boundary layer transitions was analyzed by using 0 ° angle of attack cone and HIFiRE-5 profile at different Reynolds numbers. The results show that both of the two methods can correctly reflect the change trend of the initial position and the length of the transition zone with the Reynolds number in the hypersonic boundary layer, but can not capture the peak value of the heat flow in the transition zone. The laminar flow + The heat transfer coefficient calculated by the model is higher in the turbulence region than in the k-ω-γ transition mode. For both HIFiRE-5 profiles with unstable flow and cross-flow instability, the improved k-ω-γ transition mode and the improved “laminar flow + transition criterion” model are more accurate than the original model For the boundary layer transition caused by the inflection point of the velocity profile in the vicinity of the centerline, the “Laminar + Transition Criterion” model is predicted by the correlation with the boundary layer thickness Of the transfer position of the front of the test results, k-ω-γ transfer mode consistent with the test results very well.