Accession Number : ADA299092

Title :   Reaction Zone Models for Vortex Simulation of Turbulent Combustion.

Descriptive Note : Annual technical progress rept. no. 2,

Corporate Author : MASSACHUSETTS INST OF TECH CAMBRIDGE DEPT OF MECHANICAL ENGINEERING

Personal Author(s) : Ghoniem, Ahmed F.

PDF Url : ADA299092

Report Date : 01 OCT 1994

Pagination or Media Count : 95

Abstract : We pursued the development of a reaction zone model which can be used in the numerical simulation of turbulent combustion. We focused our attention on the high Reynolds number, high Damkohler number case in which the reaction zone thickness is much smaller than the thickness of the small scales of turbulence. Furthermore, we treated the case in which the entire flame thickness, including both the convection-diffusion zone and the reaction zone, is smaller or equal to the small scale of turbulence. Accordingly, we developed on unsteady strained, multistep chemistry and diffusion thin flame model which is based on the fundamental equations governing the convection-diffusion-reaction balance within the flame structure, while assuming that the strain rate remains constant within the flame. Moreover, we compared the results of a computation of an exothermic, finite rate kinetics model of a reacting shear layer with those obtained using an infinite rate kinetics case. This comparison established the fact that the impact of heat release on the flow, mixing and dynamics can be obtained using a thin flame model. In the coming year, we will focus on linking the thin flame, finite rate chemistry model to the flow simulation code and develop the proper set of boundary conditions of the flame model in order to expand its regime of applicability.

Descriptors :   *MATHEMATICAL MODELS, *COMBUSTION, SHEAR PROPERTIES, SIMULATION, THICKNESS, HIGH RATE, DYNAMICS, LAYERS, NUMERICAL ANALYSIS, RATES, TURBULENCE, VORTICES, STRAIN RATE, BOUNDARIES, CODING, CHEMISTRY, SCALE, THINNESS, DIFFUSION, FLOW, KINETICS, FLAMES, EQUATIONS, HEAT, REYNOLDS NUMBER, TURBULENT DIFFUSION.

Subject Categories : Operations Research
      Combustion and Ignition

Distribution Statement : APPROVED FOR PUBLIC RELEASE