Investigation of Swirling Kerosene Flame Extinction using Flamelet Generated Manifold Model

Advances in computational resources are making Computational Fluid Dynamics (CFD) increasingly accessible for a variety of engineering applications. However, certain complex problems, such as simulating detailed flame kinematics, remain computationally prohibitive for many users. Developing cost-effective methods to simulate these challenges would greatly benefit applications involving flame dynamics, such as turbine engines or industrial burners. This study investigates the lean blowout behavior of a swirling kerosene flame using the commercial CFD software Ansys Fluent. The primary objective of the study is to assess the accuracy of the Flamelet Generated Manifold (FGM) combustion model in predicting flame extinction. The Cambridge Swirl Burner, featuring a single-stage swirler, has been selected as the burner under investigation given the extensive experimental data available to validate the current work. The hybrid RANS-LES turbulence model, Stress Blended Eddy Simulation (SBES) was selected to model the turbulence fluctuations, which is a key component of local extinction, while avoiding the computational requirements of full LES. The results demonstrated that FGM models can capture transient near-blowout phenomena such as local extinction and flame liftoff for kerosene flame. An extinction was also captured at an equivalence ratio of 0.187. However, this event was likely initiated through numerical instabilities. Further refinement and stabilization of the model is necessary to correctly capture the actual blowout limit.