Zhiyi Li, Alberto Cuoci, Alessandro Parente (ULB)

The present work focuses on the validation with OpenFOAM for the numerical simulation of turbulent combustion under Moderate or Intense Low-oxygen Dilution (MILD) combustion. Results for a Jet-in-Hot-Coflow (JHC) burner using a mixture of CH4 and H2 50/50 on molar basis are presented and discussed, with the objective of showing the sensitivity of the results to modelling parameters and numerical approach. Simulation were performed using Eddy Dissipation Concept (EDC) combustion model combined with edcPimpleSMOKE, a RANS transient solver coupled to the OpenSMOKE tool for stiff chemistry management. A 2D mesh with 30,000 computational cells is used. The sensitivity of the simulation results to different modelling choices is presented. This includes the sensitivity to the choice of the k-epsilon model parameters, the choice of canonical reactor simulating the fine structures and the EDC model coefficient. Moreover, the impact of molecular and turbulent diffusion on the results will be assessed, by investigating the effect of turbulent Schmidt number and considering the unbalanced influence of thermal to mass diffusion with non-unity Lewis Number. Finally, the combination of EDC combustion model with in-situ adaptive tabulation (ISAT) is presented, to assess the potential of computational time reduction.