Parametric analysis of Velocity Conditioned Modified Curl’s Model (VC-MCM) in the PDF method for Turbulent Non-Premixed Flames

In the probability density function (PDF) method for turbulent combustion, model for molecular diffusion process is required and has large influence on the accuracy of numerical simulations. While most of the existing mixing models can ensure that scalar mean does not change and the scalar dissipation rate is correct, they neglect the possible effect of velocity on the mixing process. However, the Direct Numerical Simulation (DNS) shows that such neglection is only valid if the flow is completely local anisotropic. Therefore, local isotropy requires a velocity-conditioned mixing model. Therefore, in this work, a velocity-conditioned modified Curl’s model is introduced and applied for well-known turbulent non-premixed flames, Sandia Flame series D-F. The influence of model parameters such as mixing parameter and the turbulence parameters are investigated based on general Modified Curl’s Model and Velocity-Conditioned Modified Curl’s Model are compared, together with the experimental data. Moreover, effects of Reynolds number on the model calculations are also investigated. The computational requirements along with the useful results are also discussed in this research work for the both the models.