This paper describes analyses of the dynamics of harmonically forced, turbulent flames. It particularly focuses on the modulation of the ensemble averaged turbulent burning velocity by the harmonic forcing, S_(T,eff)(s,t) = S_(T,eff)(s) + S_(T,eff)'(s,f). The flame dynamics are analyzed computationally by solving the three-dimensional level set equation within an iso-density framework, extracting the instantaneous flame position, and ensemble averaging the results. We show that S_(T,eff)' has an inverse dependence upon the instantaneous, ensemble averaged flame curvature, an effect that scales with turbulence intensity and harmonic excitation amplitude. We show that this curvature dependence follows from basic application of Huygens propagation to flames with stochastic wrinkling superposed upon base curvature. Finally, we propose a model equation to describe the ensemble averaged turbulent flame dynamics which includes this effect.
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