Progress variable based filtered turbulent flame model and its application to a swirl-stabilised flame

In turbulent combustion simulation, the swirl flame is an important case because of its widespread applications and modelling complexity. Upon this issue, the filtered turbulent flame model (FTFM) is updated to FTFM-C to better describe extinction and reignition in the flow field. Although both FTFM and FTFM-C are modelling advantageous in the sense that entry parameters are computationally available, FTFM-C is expected to be more capable of predicting species concentrations. The performance of FTFM-C is first validated with laminar counterflow flame to exclude possible numerical interferences and the Sydney bluff-body jet flame HM1 within the framework of large eddy simulation. In studying the Sydney swirl flame SMH1 case, the obtained results from FTFM-C demonstrate that the upstream recirculation zone and the downstream vortex breakdown region can be well captured. A detailed comparison between the FTFM-C predictions and experimental measurements is presented, along with the literature results from the steady laminar flamelet model and the multi-environment filtered density function model. FTFM-C shows acceptable performance, with particular improvements in capturing the flame surface position.