Gas turbine combustor with turbulence enhanced mixing fuel injectors

TLDR: In this article, the primary gas fuel spray bars are aerodynamically shaped and a row of fuel discharge ports are formed on opposing sides of the spray bar sides to create turbulence in the air flow that ensures adequate mixing of fuel and air.

Abstract: A combustor for a gas turbine having primary and secondary combustion zones. The combustor has primary gas fuel spray pegs for supplying a lean mixture of gaseous fuel to the primary combustion zone via a first annular pre-mixing passage and secondary fuel spray bars for supplying a lean mixture of fuel to the secondary combustion zone via a second annular pre-mixing passage. The fuel spray bars are aerodynamically shaped and a row of fuel discharge ports are formed on opposing sides of the spray bar. A pair of mixing fins project outwardly from the spray bar sides. The fins create turbulence in the air flow that ensures adequate mixing of the fuel and air. The fins have sufficient height and are displaced sufficiently far from the fuel discharge ports so that although the turbulence has not dissipated by the time the air flow reaches the fuel discharge ports, the zone of recirculation located downstream from the fins does not extend to the fuel discharge ports. This ensures that the spray bars will not act as flame holders and cause combustion to occur prematurely within the pre-mixing passage.