A dynamic eddy-viscosity model based on the invariants of the rate-of-strain
A dynamic eddy-viscosity model based on the invariants of the rate-of-strain
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基于应变率不变量的动态涡粘模型
DOI：
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发表时间：
2011
期刊：
影响因子：
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通讯作者：
P. Moin
中科院分区：
文献类型：
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作者：
R. Verstappen;S. Bose;Jungil Lee;Haecheon Choi;P. Moin
大涡模拟（LES）旨在预测空间过滤湍流的动力学。通过构造，LES解仅包含大小≥ λ的尺度，其中λ表示空间滤波器的某些用户选择的长度尺度。基于涡粘性模型的大涡模拟和Navier-Stokes模拟仅在扩散系数上有所不同。因此，我们关注的问题是：“什么时候涡扩散率减少湍流的大小≥ 100？"。推导出涡粘滞系数νe必须依赖于应变率张量的两个不变量q和r。我们提出了一个动态版本的涡粘性模型和各向同性湍流和湍流通道流的LES目前的结果。
Large-eddy simulation (LES) seeks to predict the dynamics of spatially filtered turbulent flows. By construction, the LES solution contains only scales of size ≥ ∆, where ∆ denotes some user-chosen length scale of the spatial filter. A large-eddy simulation based on an eddy-viscosity model and a Navier-Stokes simulation differ only in diffusion coefficient. Therefore, we focus on the question: “When does eddy diffusivity reduce a turbulent flow to eddies of size ≥ ∆?”. It is deduced that the eddy viscosity νe has to depend on the two invariants q and r of the filtered rate-of-strain tensor. We present a dynamic version of the resultant eddy-viscosity model and present results from LES of isotropic turbulence and turbulent channel flow.