Internal and External Aerodynamics of a Lean Burn Gas Turbine Fuel Injector

The internal aerodynamics of a lean burn gas turbine fuel injector confined is numerically investigated to understand the recirculation zone characteristics and shear layer interaction. The injector design is based on lean burn fuel injection concepts adopted in aero-engine combustors. Geometry involves a pilot and main mixer assembly which contains co-rotating and counter-rotating swirler arrangements separated by multiple fuel passages. The CFD formulation was based on the standard k-ε model. The model was then numerically resolved using methods of area-mass-flow rate-based techniques with preconditioning and calculated average velocities and turbulence characteristics. The central toroidal recirculation zone (CTRZ) formation by the pilot and main swirlers is captured and the shear layer structure is quantified at different axial locations.