Accession Number:

ADA272723

Title:

Reaction Zone Models for Vortex Simulation of Turbulent Combustion

Descriptive Note:

Annual technical progress rept. 1 Sep 92-31 Aug 93,

Corporate Author:

MASSACHUSETTS INST OF TECH CAMBRIDGE DEPT OF MECHANICAL ENGINEERING

Personal Author(s):

Report Date:

1993-10-01

Pagination or Media Count:

111.0

Abstract:

During the first year of this effort, two related issues were investigated 1 establishing the validity of the thin flame model when used to compute flow-combustion interactions in a turbulent shear layer 2 developing an efficient methodology to compute the unsteady strained flame structure when the flame thickness is much smaller than the flow scale. In the first effort, the transport element method was applied to compute a a reacting flow in which combustion proceeds according to a single-step, temperature dependent Arrhenius reaction, and b a mixing-limited model in which Schvab-Zeldovich variables are used to obtain the infinite speed chemistry results. The results of both computations showed that, at high Damkohler numbers, while there is a small error in the prediction of the total burning rate using the second approach, the second model accurately estimates the effect of combustion on the flow dynamics in terms of volumetric expansion and vorticity generation. Work on the second project resulted in a more efficient model to compute the flame structure under conditions of unsteady strain. The computational model is based on a series of mathematical transformations which reduce the governing equations to time- dependent reaction-diffusion equations. Turbulent Combustion, Numerical Simulation, Vortex Methods, Combustion Models.

Subject Categories:

  • Fluid Mechanics
  • Combustion and Ignition

Distribution Statement:

APPROVED FOR PUBLIC RELEASE