Computational Analysis of Reacting Flows in Afterburner

摘要

Gas turbine afterburner is used during take-off, combat, maneuvers, and emergencies when the aircraft engine needs more thrust than normal. A 60° sector full-scaled afterburner, with extended domain of three times the nozzle diameter in the axial direction and two times the nozzle diameter in the radial direction, is modeled. The numerical calculations are performed using SIMPLE algorithm and k-ε model has been used for turbulence. Kerosene (C_(12)H_(23)) is taken as fuel and virtual injectors are specified for fuel injection. Energy equation and species transport with the Discrete Phase model is selected for computations. Maximum density of 1.25 kg/m~3 is observed and the density of the fluid reduced to 0.2 kg/ m~3 at the exit of nozzle after combustion. The desired Mach number of 1.1 could be observed at the exit of the nozzle. The CO_2 mass fraction increased from 0 to 0.075 whereas the O_2 mass fraction decreased from 0.23 to 0.145 from the inlet to the exit of afterburner. The maximum temperature of 2500 K is observed radially at 0.2 m, from the center of the afterburner and axially at a distance of 0.9 m of afterburner. The obtained results are validated with published experimental and computational fluid dynamics results.