REFINEMENT OF THE SPECTRAL MODEL OF TURBULENT BURNING VELOCITY (IN THE CASE OF STOICHIOMETRIC MIXTURES)

The formerly proposed spectral model of turbulent mass burning velocity is refined for practical use. The model is expressed by an integral form of the product of two independent functions. One is the turbulence energy spectrum and the other is the characteristic spectrum solely related to the mixture properties, such as laminar burning velocity and laminar flame thickness. Refinements are made in regard to the following three points: (1) a small modification in the characteristic spectrum of the mixture, (2) consideration of turbulence spectrum shape variation with turbulence intensity and (3) a new idea regarding the upper limit of the integral which is strongly related to the small-scale structure of the turbulent flame. The predicted velocities for stoichiometric mixtures are compared with the measured turbulent mass burning velocities, where the laminar burning velocity, laminar flame thickness and turbulence intensity are varied extensively and independently with each other. The comparison shows fairly good quantitative consistency.