Transport properties in turbulent premixed flames
نویسندگان
چکیده
In order to evaluate transport properties in turbulent premixed flames, a propagating turbulent premixed flame in an incoming homogeneous isotropic turbulence is directly simulated assuming a single-step irreversible Arrhenius-type reaction. To investigate the production of turbulent kinetic energy in the flame region, Favre averaged transport equation of turbulent kinetic energy along streamwise direction is analyzed. It is shown that the mean pressure gradient term, pressure dilatation and dilatation dissipation terms have important roles. Favre averaged transport equation of turbulent scalar flux along streamwise direction is then analyzed to investigate the turbulent scalar flux. It is shown that the fluctuating pressure term, mean pressure gradient term and velocity-reaction rate correlation term play important roles on appearance of counter-gradient diffusion.
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