A brief introduction of the time-filtered Navier–Stokes (TFNS) equations for very large eddy simulation (VLES) and its distinct features is presented. A set of nonlinear subscale models and their advantages over the linear subscale eddy viscosity models are described. A guideline for conducting a TFNS/VLES simulation is also provided. In this paper, we present simulations for three turbulent flows. The first one is the turbulent pipe flow at both low and high Reynolds numbers to illustrate the basic features of TFNS/VLES; the second one is the swirling turbulent flow in an LM6000 single injector to further demonstrate the differences between the results from nonlinear models versus linear viscosity models; the third one is a more complex turbulent flow generated in a single-element lean direct injection combustor, which demonstrates that the current TFNS/VLES approach is capable of predicting dynamically important, unsteady turbulent structures even with a relatively coarse mesh grid.

中文翻译：

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用于湍流超大涡模拟的非线性子尺度湍流模型

简要介绍了用于超大涡模拟 (VLES) 的时间滤波纳维 - 斯托克斯 (TFNS) 方程及其独特的特征。描述了一组非线性子尺度模型及其相对于线性子尺度涡粘性模型的优势。还提供了进行 TFNS/VLES 模拟的指南。在本文中，我们对三种湍流进行了模拟。第一个是低雷诺数和高雷诺数下的湍流管流，以说明 TFNS/VLES 的基本特征；第二个是 LM6000 单喷射器中的涡流湍流，以进一步证明非线性模型与线性粘度模型的结果之间的差异；第三个是在单元件贫燃直喷燃烧器中产生的更复杂的湍流，