Towards Modeling Lean Blow Out in Gas Turbine Flameholder Applications

Abstract

The objective of this study was to assess the accuracy of the large-eddy simulation (LES) methodology, with a simple combustion closure based on equilibrium chemistry, for simulating turbulent reacting flows behind a bluff body flameholder. Specifically, the variation in recirculation zone length with change in equivalence ratio was calculated and compared to experimental measurements. It was found that the present LES modeling approach can reproduce this variation accurately. However, it understated the recirculation zone length at the stoichiometric condition. The approach was assessed at the lean blow out condition to evaluate its behavior at the lean limit and to analyze the physics of combustion instability.