The reliability of the improved eN method for the transition prediction of boundary layers on a flat plate
The reliability of the improved eN method for the transition prediction of boundary layers on a flat plate
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DOI：
10.1007/s11433-012-4692-y
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发表时间：
2012-03
期刊：
影响因子：
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通讯作者：
Caihong Su
中科院分区：
文献类型：
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作者：
Caihong Su
在改进的eNmethod中，过渡判据是当扰动速度幅值达到自由流速度的1% ~ 2%时发生过渡，而在传统的eNmethod中，then因子是经验因子。本文用抛物化稳定方程（PSE）的过渡预测结果验证了改进方法中这一关键假设的可靠性。分别用改进的eNmethod和PSE方法对平板上不可压缩边界层和高超声速边界层在马赫数为6时的过渡位置进行了预测。两种方法的计算结果吻合较好，说明改进的eNmethod所提出的过渡判据是可靠的。
The transition criterion in the improved eNmethod is that transition would occur whenever the velocity amplitude of disturbance reaches 1%–2% of the free stream velocity, while in the conventional eNmethod, theNfactor is an empirical factor. In this paper the reliability of this key assumption in the improved eNmethod is checked by results of transition prediction by using the Parabolized Stability Equations (PSE). Transition locations of an incompressible boundary layer and a hypersonic boundary layer at Mach number 6 on a flat plate are predicted by both the improved eNmethod and the PSE method. Results from both methods agree fairly well with each other, implying that the transition criterion proposed in the improved eNmethod is reliable.