Fundamental understanding of turbulent flame propagation in droplet-laden reactant mixture based on experimental and numerical investigations

本计画的目的是利用实验与直接数值模拟（DNS）来研究含液滴混合物中紊流火焰传播的统计特性。湍流强度、湍流积分长度尺度、群数、挥发度、液滴直径和当量比的影响（包括整体和气相）对含液滴混合物中湍流火焰传播的影响将通过进行广泛的参数研究来详细分析，以获得这些参数对火焰传播统计的影响的基本物理理解，燃烧速率和污染物形成（例如NOx生成速率）。虽然在有限的程度上解决了在过去的实验研究，广泛的DNS为基础的调查这个问题，支持，并直接比较，实验尚未在现有的文献中报道。在这个项目中，从DNS和实验数据的基本物理理解将被用来开发模型的背景下，火焰和条件矩封闭（CMC）的反应速率关闭。火焰传播到液滴负载的混合物和它的建模的基本理解将提供一个强大的成本效益的计算流体动力学（CFD）为基础的设计工具，可靠的，节能的和清洁的燃烧装置，涉及液滴负载的混合物（例如，直接喷射（DI）发动机，压缩点火（CI）发动机，航空燃气轮机等）。

This project aims to investigate the statistical behaviour of turbulent flame propagation in a droplet-laden mixture using both experiments and Direct Numerical Simulations (DNS). The effects of turbulence intensity, integral length scale of turbulence, group number, volatility, droplet diameter, and equivalence ratio (both overall and gaseous phase) on turbu-lent flame propagation in droplet-laden mixtures will be analysed in detail by carrying out extensive parametric studies to obtain fundamental physical understanding of the influences of these parameters on the flame propagation statistics, burning rate and pollutant formation (e.g. NOx generation rate). Although addressed to a limited extent by experimental studies in the past, an extensive DNS based investigation of this problem, supported by, and directly compared with, experimentation is yet to be reported in the existing literature. In this project, the fundamental physical understanding from both DNS and experimental data will be used to develop models in the context of the flamelets and Conditional Moment Closure (CMC) based reaction rate closures. Fundamental understanding of flame propagation into droplet-laden mixtures and its modelling will provide a robust cost-effective Computational Fluid Dynamics (CFD) based design tool for reliable, energy-efficient and cleaner combustion devices involving droplet-laden mixtures (e.g. Direct Injection (DI) engines, Compression Ignition (CI) engines, Aero gas turbines etc.).