Modeling of spray flame in gas turbine combustors with LES and FGM

Abstract

A large eddy simulation formulation was proposed for spray combustion in gas turbine combustion chambers, using a FGM combustion model coupled with detailed chemical reaction mechanisms. The solver was developed using the open-source toolkit—OpenFOAM. The two-way coupling between spray particles and gas field was modeled by a Eulerian–Lagrangian method. The enthalpy loss resulting from spray evaporation was also considered in the FGM combustion model. The solver was first validated against the experimental data of a model combustion chamber. The predictions of mean and fluctuation velocities were in good agreement with the experimental values for both cold and reacting flows, and the flame shapes were also nicely reproduced. It was revealed that there existed local extinctions at the swirler exit, leading to a lift-off flame. The validated solver was then applied to a realistic combustor of an aeroengine. It was found that different from the diffusive nature of the flame in the model combustor, the spray combustion in the realistic combustor is of partially premixed nature. The predicted pressure loss and the exit temperature profile agreed rather well with the measurements, demonstrating the capability of the present solver to simulate realistic combustors with complex geometries.