Low-dimensional models for flows with density fluctuations
Low-dimensional models for flows with density fluctuations
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DOI：
10.1063/1.869321
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发表时间：
1997-07
影响因子：
4.6
通讯作者：
J. Lumley;A. Poje
中科院分区：
文献类型：
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作者：
J. Lumley;A. Poje
低维模型，使用适当的正交，或Karhunen-Loeve分解，在表示湍流边界层的壁区的行为方面是非常成功的。我们简要总结这项工作。我们希望在相干结构起重要作用的其他流动中，特别是在具有密度涨落的流动中，也能取得类似的成功。我们勾勒出这样一个分解的方法，密度波动的流量，建议不同的替代品，权衡可用的信息。在这样的低维模型中，获得经验本征函数是一个问题，因为它们通常只能通过广泛的测量或直接的数值模拟来确定。然而，最近的工作与能量方法的稳定性理论（修改通过使用各向异性的涡动粘度和反馈的平均配置文件）已经非常成功地预测的形式的经验本征函数在等温边界层。我们在这里介绍的是……
A low-dimensional model, using the proper orthogonal, or Karhunen–Loeve decomposition, has been remarkably successful in representing the behavior of the wall region of a turbulent boundary layer. We briefly summarize this work. We may hope for similar success in other flows in which coherent structures play an important role, in particular flows with density fluctuations. We sketch an approach to such a decomposition for flows with density fluctuations, suggesting various alternatives which weigh the available information differently. In such a low-dimensional model, obtaining the empirical eigenfunctions poses a problem, since they can usually be determined only from extensive measurements or direct numerical simulations. However, recent work with energy method stability theory (modified by use of an anisotropic eddy viscosity and feedback to the mean profile) has been remarkably successful in predicting the form of the empirical eigenfunctions in the isothermal boundary layer. We present here prelimina...