LES of Sooting Flames

Abstract

Soot prediction in realistic systems is one of the most challenging problems in theoretical and applied combustion. Soot formation as a chemical process is very complicated and not fully understood up to the moment. The major difficulty stems from the chemical complexity of the soot formation processes as well as its strong coupling with the other thermochemical and fluid processes that occur simultaneously. Soot is a major byproduct of incomplete combustion, having a strong impact on the environment, as well as the combustion efficiency. Therefore, it needs to be predicted in realistic configurations in an accurate and yet computationally efficient way. In the current study, a new soot formation subgrid model is developed and reported here. The new model is designed to be used within the context of the Large Eddy Simulation (LES) framework, combined with Linear Eddy Mixing (LEM) as a subgrid combustion model. The final model can be applied equally to premixed and non-premixed flames over any required geometry and flow conditions in the free, the transition, and the continuum regimes. The soot dynamics is predicted using a Method of Moments approach with Lagrangian Interpolative Closure (MOMIC) for the fractional moments. Since, no prior knowledge of the particles distribution is required, the model is generally applicable. The effect of radiation is introduced as an optically thin model. As a validation the model is first applied to a non-premixed non-sooting flame, then a set of canonically premixed flames. Finally, the model is validated against a non-premixed jet sooting flame. Good results are predicted with reasonable accuracy.

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Document Details

Document Type
Technical Report
Publication Date
Dec 01, 2006
Accession Number
ADA469968

Entities

People

  • Hossam El-asrag
  • Suresh Menon

Organizations

  • Georgia Tech

Tags

Communities of Interest

  • Biomedical
  • Energy and Power Technologies

DTIC Thesaurus Topics

  • Burning Rate
  • Chemical Kinetics
  • Chemical Products
  • Chemical Reactions
  • Chemical Synthesis
  • Chemistry
  • Combustion
  • Computational Fluid Dynamics
  • Computational Science
  • Differential Equations
  • Fluid Dynamics
  • Gas Turbines
  • Heat Transfer
  • Large Eddy Simulation
  • Physics Laboratories
  • Rate Of Formation
  • Turbulent Mixing

Readers

  • Combustion science or combustion engineering.
  • Computational Modeling and Simulation
  • Fluid Mechanics and Fluid Dynamics.