Investigation of the Laminar Flamelet Model of Turbulent Diffusion Flames

由于热化学方程和三维纳维-斯托克斯方程之间的耦合，对非预混合湍流燃烧进行建模是一项艰巨的任务。 人们有强烈的动机将化学问题与湍流分开。 层流火焰模型是一种重要的解耦方法，并且经常用于当前的燃烧建模中。 本研究的主要目标是调查湍流扩散火焰层流火焰模型的有效性。实现这一科学目标的方法是对湍流扩散火焰情况进行直接数值模拟。 在化学保持简单的情况之一中，通过模拟进行的研究将与理论研究相结合。 为了研究氢火焰的真实模型，部分平衡化学模型将与 3D 纳维-斯托克斯方程结合使用。 分析研究将与其他地方正在进行的实验室工作相互作用进行。 提高对层流火焰建模有效性的理解将极大地促进湍流火焰建模工作，并最终应用于燃烧系统中的关键问题，例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.