Effect of Stoichiometry and Strain Rate on Transient Flame Response

Abstract

The interaction of a premixed methane/air flame with a counter-rotating vortex pair is analyzed using a parallel low-Mach-number computational model that is based on a detailed C1C2 chemical mechanism. Attention is focused on the transient response of the heat release rate and the flame structure at the centerline of the vortex pair. Results are obtained for vortex pairs of different strengths under lean, stoichiometric, and rich conditions. For the range of vortex strengths considered, the computations indicate that the heat release rate in the rich flame decays significantly faster than in the stoichiometric flame; this behavior is consistent with recent experimental measurements. Meanwhile, the heat release rate in the lean flame decays at a slightly slower rate than in the stoichiometric flame. The transient response of flame radicals such as H, CH, OH, and HCO is also analyzed. The analysis reveals a complex nonlinear dependence of the transient structure on both the vortex strength and the stoichiometry.

Open PDF

Document Details

Document Type
Technical Report
Publication Date
Aug 04, 2000
Accession Number
ADA457954

Entities

People

  • Habib N. Najm
  • Omar M. Knio

Organizations

  • Johns Hopkins University

Tags

Communities of Interest

  • Energy and Power Technologies

DTIC Thesaurus Topics

  • Chemical Reactions
  • Combustion
  • Equations
  • Flames
  • Flow
  • Fuel Consumption
  • Heat Transfer
  • Mach Number
  • Mechanical Engineering
  • Production Rate
  • Research Facilities
  • Simulations
  • Stoichiometry
  • Strain Rate
  • Thermal Conductivity
  • Transport Properties
  • Two Dimensional

Fields of Study

  • Physics

Readers

  • Combustion science or combustion engineering.
  • Fluid Mechanics and Fluid Dynamics.