LES of the Ignition Process of Non-premixed CH4 based on Dynamic Thickened Flame Model

Abstract

Abstract. Improve the accuracy of ignition calculate simulation through dynamic thickening of the of flame front in order to achieve Large Eddy Simulation (LES) solution scales. Taking the WALL model which takes the sticky near the wall into account as the sub-grid turbulence model, simulating the process of energy releasing of spark plug by the way of adding Gauss heat source to the energy function. 40ms of the ignition process is calculated based on the cold state flow field, and compare the numerical simulation results with corresponding experimental results abroad. It shows: The simulation accuracy of cold flow field of LES is good, and be able to capture small-size vortex; Large Eddy Simulation based on dynamic thickening flame model is an effective method to predict the dynamic diffusion processes of CH 4 non-premixed flame; Recirculation zone plays an important role of fuel distribution, flame spread and stability.