Patent ID: 8590310

Claim:
A fuel system for dividing fuel between primary and secondary nozzles in a gas turbine engine, the fuel system comprising: primary and secondary fuel nozzles coupled to a combustor in the gas turbine engine; a fuel pump that generates a fuel flow; a first flow divider valve that receives the fuel flow and divides fuel to the primary and secondary fuel nozzles, the first flow divider valve comprising: a valve housing having an inlet for receiving the fuel flow; means for providing primary fuel to the primary fuel nozzles comprising a spring-actuated piston valve disposed within the valve housing to maintain a backpressure in the fuel flow that routes the primary fuel through a first fuel line extending between the inlet and the primary nozzles; and means for providing secondary fuel to the secondary fuel nozzles while progressively decreasing the pressure drop across the means for providing the secondary fuel to the secondary fuel nozzles, the means for providing secondary fuel to the secondary fuel nozzles comprises: a window in the valve housing disposed along the piston to route the secondary fuel through a second fuel line; and a second flow divider valve disposed within the valve housing and coupled to the second fuel line and a plurality of outlets fluidly coupled to the secondary nozzles.