LES of a Premixed Jet Flame in Cross-Flow

In this work, we conduct a preliminary analysis of a premixed jet flame in a vitiated cross-flow, a configuration that closely represents axially-staged combustion. In recent times this concept has gained significant attention of gas turbine manufacturers due to its greater fuel flexibility and lower NOx emissions. Large-eddy simulation (LES) is used to model a methane-air jet with an equivalence ratio (f) of 1.1 injected into a vitiated crossflow (f = 0.575, T = 1623 K) at an elevated pressure (5 atm). The simulation is carried out with a compressible high-order accurate numerical solver (S3D). Sub-grid scale fluxes are modelled using artificial fluid properties (AFP) and the chemical source term is closed with a well-mixed assumption. Trajectory and flow field of the JICF are captured reasonably well. The analysis is focused on flame stabilisation and the simulation results showed that the flame is lifted from the jet exit with an anchoring point on the leeward side of the jet. Further, it was also found that auto-ignition might play an important role in flame stabilisation and structure.