Research Initiation Award: Experimental Study on Laminar and Turbulent Flame Thickness

本项目旨在获得火焰厚度对拉伸、优先扩散和湍流的响应。它提出了三个具体目标：(i)发展一种使用速度分布来定义和量化火焰厚度的创新概念，以便能够轻松准确地进行有意义的评估；（ii）得到一维绝热预混火焰厚度；（iii）获得火焰厚度对物理化学参数的响应，以便与理论预测进行比较。此外，该程序的结果可以为将该概念扩展到非预混火焰提供基础。用激光多普勒测速法得到了速度分布和条件速度统计。逆流喷嘴配置将用于稳定平面绝热火焰。从这个实验研究中获得的结果将是有价值的，因为(i)它们将验证一种评估火焰厚度的简单方法，这是火焰的固有特性；（ii）它们将整合目前使用的众多定义，从而促进其描述和用法的统一；(3)补充和测试火焰厚度的理论研究。由于火焰厚度被广泛用于描述火焰的行为，对火焰稳定和解释湍流燃烧至关重要，因此本文的研究对燃烧科学和技术具有基础和实际意义。

This project aims to obtain the flame thickness response to stretch, preferential diffusion, and turbulence. It proposes three specific objectives: (i) develop an innovative concept of using velocity profiles to define and quantify flame thicknesses such that they can be meaningfully evaluated with ease and accuracy; (ii) obtain one-dimensional, adiabatic, premixed flame thicknesses; (iii) obtain flame thickness response to physico-chemical parameters for comparison with theoretical predictions. Furthermore, the results from this proposed program may provide a basis for extending the concept to nonpremixed flames. The velocity profiles and conditional velocity statistics will be obtained by using laser doppler velocimetry. A counterflow nozzle configuration will be used to stabilize planar, adiabatic flames. The results obtained from this proposed experimental study will be valuable because (i) they will validate a simple method of evaluating the flame thickness which is an intrinsic property of flames; (ii) they will consolidate numerous definitions in use presently, thereby promoting unity in its description and usage; and (iii) they will complement and test theoretical studies on flame thickness. Because flame thickness has been extensively used in describing behavior of flames important in flame stabilization and for interpreting turbulent combustion, the proposed study is of fundamental and practical importance to combustion science and technology.