Patent ID: 8820087

Claim:
A method of controlling delivery of fuel to a plurality of duplex nozzles in the combustor of a gas turbine, each duplex nozzle including a primary orifice and a secondary orifice defining an orifice pair, the method comprising: providing a flow divider having a single fuel inlet and a plurality of fuel outlets, the flow divider providing a separate positive displacement of fuel to each of the outlets, metering an equal fuel flow in tandem to each of the fuel outlets; providing a single primary fuel supply line connected to each fuel outlet of the flow divider, wherein each primary fuel supply line is separated from fluid communication with any other primary fuel supply line; conveying a liquid fuel from the fuel outlets through each respective primary fuel supply line at a predetermined rate; supplying the fuel from each primary fuel supply line to the primary orifice of a respective duplex nozzle; providing a secondary fuel supply line for each primary fuel supply line, each secondary fuel supply line having an inlet connected to a respective primary fuel supply line between the primary orifice in a respective duplex nozzle and the connection of the primary fuel supply line to a respective fuel outlet of the flow divider, wherein each secondary fuel supply line extends from a respective primary fuel supply line to a secondary orifice in the respective duplex nozzle; providing a valve between the connection of each secondary fuel supply line to a respective primary fuel supply line and a respective secondary orifice; identifying a predetermined operating condition of the gas turbine; and producing a valve actuating signal in response to identifying the predetermined operating condition, the valve actuating signal effecting actuation of the valves in the secondary fuel supply lines from a closed position to an open position whereby, for each orifice pair, fuel from each primary fuel supply line is conveyed through both the secondary orifice and the primary orifice located in the respective duplex nozzle.