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Chemical Reaction Rate Effects in Turbulent Non-premixed Combustion

  • H. Bockhorn
Conference paper
Part of the Springer Series in Synergetics book series (SSSYN, volume 48)

Abstract

A turbulent combustion model without simplifying assumptions about the chemical reactions is evaluated by means of a sensitivity analysis. The turbulence model is conventional and based on gradient transport assumptions and an eddy viscosity concept. In addition to the equations of the turbulent flow field the species conservation equations are solved. The chemical reactions are described by a detailed, elementary kinetics reaction mechanism. The source terms in the species conservation equations are treated by means of a presumed-shapepdf-closure relaxing the assumption of statistically independent variables. The sensitivity analysis for the turbulent combustion model is performed in terms of the local first order sensitivity coefficients. The sensitivity analysis demonstrates the limitations of the turbulence model and the relative importance of single elementary steps of the reaction mechanism. From this, some arguments for the simplification of the closure for the mean chemical reaction rates are derived.

Keywords

Rate Coefficient Diffusion Flame Sensitivity Coefficient Combustion Model Scalar Dissipation Rate 
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Copyright information

© Springer-Verlag Berlin, Heidelberg 1990

Authors and Affiliations

  • H. Bockhorn
    • 1
  1. 1.Institut für Chemische TechnologieTechnische Hochschule DarmstadtDarmstadtFed. Rep. of Germany

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