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.
