Development and Implementation of Practical Optimal LES Models

实用最优 LES 模型的开发和实施

• 批准号: 0352552
• 负责人: Robert Moser
• 金额: $ 2.76万
• 依托单位: University of Illinois at Urbana-Champaign
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2004
• 资助国家: 美国
• 起止时间: 2004-04-15 至 2005-04-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0352552&HistoricalAwards=false
• 关键词: Development; Implementation; Practical; Optimal; LES

ABSTRACTPROPOSAL NO.: CTS-0352552PRINCIPAL INVESTIGATOR: ROBERT D. MOSERINSTITUTION: UNIVERSITY OF ILLINOIS, URBANA-CHAMPAIGNDEVELOPMENT AND IMPLEMENTATION OF PRACTICAL OPTIMAL LES MODELS In many technological devices, it is of great importance to predict and/or control the effects of turbulent fluid flows, because the behavior of the turbulence may ultimately control the performance of the device. Large eddy simulation (LES) is one of the most promising techniques for reliable prediction of the high Reynolds number turbulent flows of technological interest. In LES, the largest scales of turbulence are simulated while the effects of the smallest scales are modeled. However, there are a number of challenges to overcome for LES to realize its full potential; these include the treatment of near-wall turbulence and the impact of numerical discretization, especially in flows with complex geometries. The objective of the proposed research is to produce LES models that will provide reliable predictions in a broad range of turbulent flows. The approach is to apply the "Optimal LES" formulation, in which LES models are developed through a formal optimization process. Optimal LES models are formulated in terms of small separation multi-point velocity correlations. The primary remaining challenge in developing such models is obtaining the required velocity correlations, without resorting to extensive empirical data. The required statistical correlations will be developed using dynamic techniques, in which the correlations are estimated from the running simulation and from theoretical considerations. Of particular interest in the current project will be modeling near-wall turbulence, scalar transport and compressibility. The results of this development will be a broadly applicable and accurate LES modeling technique, which will be implemented in application CFD codes. Optimal LES will be developed into a powerful predictive tool in a wide range of turbulent flows. This will have great impact on many engineering applications in which turbulence is one of the dominant phenomena. Important examples are: flow in gas turbine engines, flow over multi-element high-lift airfoils, and flow in stirred tank reactors. With reliable LES simulations, these and many other applications will enjoy improved new designs, and reduced design costs arising from the decreased need for testing.

摘要Propopos no。：CTS-0352552主题研究者：Robert D. Moserinstitution：伊利诺伊大学，Urbana-Champaigndevelpment和许多技术设备中实用最佳LES模型的实施，它非常重要，非常重要地预测和/或控制湍流的效果，因为最终可以控制湍流的效果。 大型涡流模拟（LES）是可靠预测高雷诺数技术兴趣的湍流的最有希望的技术之一。 在LE中，模拟了最大的湍流尺度，而最小尺度的效果进行了建模。 但是，LES要实现其全部潜力，需要克服许多挑战。这些包括处理近壁湍流的处理和数值离散化的影响，尤其是在具有复杂几何形状的流动中。拟议的研究的目的是生产LES模型，该模型将在广泛的湍流中提供可靠的预测。该方法是应用“最佳LES”公式，其中通过正式优化过程开发LES模型。 最佳LES模型是根据小分离多点速度相关性制定的。 开发此类模型的主要剩余挑战是获得所需的速度相关性，而无需诉诸广泛的经验数据。 所需的统计相关性将使用动态技术开发，其中从运行模拟和理论考虑中估算了相关性。 在当前项目中特别感兴趣的是建模近壁湍流，标量传输和可压缩性。 该开发的结果将是一种广泛且准确的LES建模技术，该技术将在应用程序CFD代码中实现。 最佳LE将被发展成为一个强大的预测工具，以广泛的湍流流。 这将对湍流是主要现象之一的许多工程应用产生巨大影响。 重要的例子是：燃气轮机发动机的流动，多元素高速翼型的流动以及搅拌罐反应器中的流动。借助可靠的LES模拟，这些和许多其他应用程序将享有改进的新设计，并且由于测试需求减少而降低了设计成本。