Development of scalar dissipation rate based reaction rate models for the large eddy simulations of premixed flames

本项目旨在开发一种有效的基于标量耗散率（SDR）的反应速率闭合方法，用于湍流预混火焰的大涡模拟（LES）。虽然基于SDR的闭包已经在非预混火焰的Reynolds average Navier Stokes （RANS）模拟中得到了很好的建立，但它们在紊流预混火焰的RANS和LES模拟中还很少见，而且目前还没有对它们在LES中的性能进行详细的评估。在本项目中，将开发基于SDR的反应速率闭包，并同时通过对明确过滤的直接数值模拟（DNS）数据的先验分析和对LES计算中模型性能的后验评估进行评估，并提供实验数据。在同时进行先验和后验分析的基础上，将开发新的模型并随后对其性能进行评估。最佳模型将在湍流预混火焰建模的LES代码中实现。高效的基于sdr的反应速率关闭将为在精益预混模式下运行的可靠、更清洁、更具成本效益的燃烧装置（例如火花点火发动机、精益预混预汽化（LPP）工业燃气轮机燃烧器）提供强大的CFD设计工具。

This project aims to develop an efficient Scalar Dissipation Rate (SDR) based reaction rate closure for the Large Eddy Simulation (LES) of turbulent premixed flames. Although SDR based closures are well established for Reynolds Averaged Navier Stokes (RANS) simulations of non-premixed flames, they are rare for RANS and LES of turbulent premixed flames, and no detailed evaluation of their performance in LES is available so far. In this project, the SDR based reaction rate closures will be developed and simultaneously assessed by a-priori analyses of explicitly filtered Direct Numerical Simulation (DNS) data, and a-posteriori evaluations of model performances in LES calculations, in a configuration for which experimental data is available. Based on the simultaneous a-priori and a-posteriori analyses, new models will be developed and their performance will subsequently be assessed. The best models will then be implemented in a LES code for turbulent premixed flame modelling. An efficient SDR-based reaction rate closure will provide a robust CFD based design tool for reliable, cleaner and cost-effective combustion devices operating in lean premixed mode (e.g. Spark Ignition engines, Lean Premixed Pre-vaporised (LPP) industrial gas turbine combustors).