Lagrangian Investigation of Local Extinction, Re-Ignition and Auto-Ignition in Turbulent Flames

Abstract

Lagrangian PDF investigations are performed of the Sandia piloted flame E and the CabraH2/N2 lifted flame to help develop a deeper understanding of local extinction, re-ignition and auto-ignition in these flames, and of the PDF models abilities to represent these phenomena. Lagrangian particle time series are extracted from the PDF model calculations and are analyzed. In the analysis of the results for flame E, the particle trajectories are divided into two groups: continuous burning and local extinction. For each group, the trajectories are further sub-divided based on the particles origin: the fuel stream, the oxidizer stream, the pilot stream, and the intermediate region. The PDF calculations are performed using each of three commonly used models of molecular mixing, namely the EMST, IEM and modified Curl mixing models. The calculations with different mixing models reproduce the local extinction and re-ignition processes observed in flame E reasonably well.

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Document Details

Document Type
Technical Report
Publication Date
Oct 01, 2008
Accession Number
AD1005702

Entities

People

  • Haifeng Wang
  • Stephen B. Pope

Organizations

  • Cornell University

Tags

Communities of Interest

  • Air Platforms
  • Energy and Power Technologies

DTIC Thesaurus Topics

  • Boltzmann Equation
  • Chemical Reactions
  • Chemistry
  • Combustion
  • Differential Equations
  • Equations
  • Experimental Data
  • Ignition
  • Ignition Lag
  • Jet Flames
  • Large Eddy Simulation
  • Particle Trajectories
  • Physical Properties
  • Reaction Mechanisms
  • Simulations
  • Statistics
  • Strain Rate

Fields of Study

  • Physics

Readers

  • Combustion science or combustion engineering.
  • Computational Fluid Dynamics (CFD)