Analysis of scalar dissipation in terms of vorticity geometry in isotropic turbulence

  title={Analysis of scalar dissipation in terms of vorticity geometry in isotropic turbulence},
  author={Michel Gonzalez},
  journal={Journal of Turbulence},
  • Michel Gonzalez
  • Published 11 September 2012
  • Physics, Environmental Science
  • Journal of Turbulence
The mechanisms promoting scalar dissipation through scalar gradient production are scrutinised in terms of vorticity alignment with respect to strain principal axes. For that purpose, a stochastic Lagrangian model for the velocity gradient tensor and the scalar gradient vector is used. The model results show that the major part of scalar dissipation occurs for stretched vorticity, namely when the vorticity vector aligns with the extensional and intermediate strain eigenvectors. More… 
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