Reduced Stress Tensor and Dissipation and the Transport of Lamb Vector
Reduced Stress Tensor and Dissipation and the Transport of Lamb Vector
复制标题
减少应力张量和耗散以及 Lamb 向量的传输
DOI：
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发表时间：
1996
期刊：
影响因子：
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通讯作者：
Jian
中科院分区：
文献类型：
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作者：
Jiezhi Wu;Ye Zhou;Jian
我们开发了一种方法，以确保应力张量，无论其数量的独立组件，可以减少到一个完全等效的一个具有相同数量的独立组件的表面力。当剪切粘度为常数时，它适用于动量平衡。直接应用这种方法的能量平衡也导致动能耗散率的减少。按照这个程序，可以实现分析和计算的显著节省。对于湍流，这种策略直接意味着在将其投入计算之前，给定的雷诺应力模型总是可以被简化的模型所取代。此外，我们展示了如何雷诺应力张量的建模可以减少到平均湍流兰姆矢量单独，这是简单得多。作为这种替代建模发展的第一步，我们推导出兰姆矢量及其平方的控制方程。这些方程形成了新的二阶封闭格式的基础，我们相信，应该有利地比较传统的雷诺应力输运方程。
We develop a methodology to ensure that the stress tensor, regardless of its number of independent components, can be reduced to an exactly equivalent one which has the same number of independent components as the surface force. It is applicable to the momentum balance if the shear viscosity is constant. A direct application of this method to the energy balance also leads to a reduction of the dissipation rate of kinetic energy. Following this procedure, significant saving in analysis and computation may be achieved. For turbulent flows, this strategy immediately implies that a given Reynolds stress model can always be replaced by a reduced one before putting it into computation. Furthermore, we show how the modeling of Reynolds stress tensor can be reduced to that of the mean turbulent Lamb vector alone, which is much simpler. As a first step of this alternative modeling development, we derive the governing equations for the Lamb vector and its square. These equations form a basis of new second-order closure schemes and, we believe, should be favorably compared to that of traditional Reynolds stress transport equation.