Influence of the Flame Sensor Formulation in the Thickened Flame Model for Large Eddy Simulations of Premixed Turbulent Flames

The Thickened Flame Model is a widely used combustion closure for Large Eddy Simulation of turbulent premixed flames. A key modeling choice within its framework is the flame sensor formulation, which controls the spatial extent over which artificial thickening is applied. This work investigates the influence of two sensor formulations on species mass fraction predictions for the turbulent Bunsen flame. Simulations are performed within the in-house MFSim platform. Results demonstrate that the sensor formulation is as impactful on solution accuracy as the maximum thickening factor itself, and that reaction-rate-based sensors are preferable for premixed combustion with detailed chemistry, as they confine thickening to the chemically active zone and preserve local heat release intensity.