Investigation of the Laminar Flamelet Model of Turbulent Diffusion Flames

由于热化学方程和三维Navier-Stokes方程之间的耦合，模拟无前置湍流燃烧是一项艰巨的任务。有一种强烈的动机将化学问题与湍流脱钩。层流火焰面模拟是一种重要的解耦方法，也是目前燃烧模拟中常用的方法。研究的主要目的是研究湍流扩散火焰的层流火焰面模型的有效性，而实现这一科学目标的途径是对湍流扩散火焰的情况进行直接的数值模拟。在化学保持简单的情况下，通过模拟进行的研究将与理论研究相结合。为了研究氢气火焰的真实模型，将局部平衡化学模型与三维Navier-Stokes方程结合使用。分析调查将与其他地方正在进行的实验室工作相互作用地进行。提高对层流火焰模型有效性的理解将大大有助于湍流火焰建模工作，最终应用于燃烧系统中的关键问题，如点火和污染物形成。

Modeling nonpremxed turbulent combustion is a formidable task due to coupling between the thermochemical equations and the three-dimensional Navier-Stokes equations. There is a strong incentive to decouple the chemistry problem from the turbulence. Laminar flamelet modeling is a salient approach to decoupling, and is often used in current combustion modeling. The principal objective of the proposed research is the investigation of the validity of laminar flamelet modeling of turbulent diffusion flames The approach to this scientific objective is to perform direct numerical simulation of turbulent diffusion flame cases. The research via simulations will be combined with theoretical investigations in one of the cases when the chemistry is kept simple. In order to investigate a realistic model of hydrogen flames the partial equilibrium chemistry model will be implemented in conjunction with the 3D Navier-Stokes equations. The analytic investigations will be performed in interaction with ongoing laboratory work elsewhere. Improved understanding of the validity of laminar flamelet modeling will significantly contribute to turbulent flame modeling efforts, with eventual applications to critical issues in combustion systems such as ignition and pollutant formation.