Large Scale Structures in Reacting Mixing Layers

  • C. Lee
  • R. W. Metcalfe
  • F. Hussain
Conference paper

Abstract

The role of large-scale coherent structures in the enhancement of mixing and chemical reaction in turbulent free shear flows has been investigated by analyzing direct numerical simulations of temporally growing reacting mixing layers. The streamwise vortical modes are found to enhance the reaction rate by convoluting the reaction surface and enhancing the mixing of the two species, although the relative significance of this effect is very sensitive to the species diffusivity. For certain Schmidt numbers, the effects of flame shortening are balanced by flame sheet stretching by the vortex pairing process. The behavior of the helicity density, dissipation, and enstrophy production in the braid region has been examined. There does not appear to be a simple correlation between the amplitude of the helicity density and the position of some very strong coherent structures in this flow.

Keywords

Combustion Vortex Convection Vorticity Convolution 

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Copyright information

© Springer-Verlag Berlin Heidelberg 1991

Authors and Affiliations

  • C. Lee
    • 1
  • R. W. Metcalfe
    • 1
  • F. Hussain
    • 1
  1. 1.Department of Mechanical EngineeringUniversity of HoustonHoustonUSA

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