Abstract: A fuel metering unit for controlling a variable displacement pump including a main metering valve in fluid communication with the pump for metering an output of the pump, a pressure regulator in fluid communication with the metering valve to create a spill return and a control valve in fluid communication with the pressure regulator and the pump for regulating the spill return flow so the spill return flow is maintained substantially constant at a low level to minimize the heat generated by recirculation by setting a displacement of the pump.

Abstract: A fuel metering unit for controlling a variable displacement pump including a main metering valve in fluid communication with the pump for metering an output of the pump, a pressure regulator in fluid communication with the metering valve to create a spill return and a control valve in fluid communication with the pressure regulator and the pump for regulating the spill return flow so the spill return flow is maintained substantially constant at a low level to minimize the heat generated by recirculation by setting a displacement of the pump.

Abstract: A fuel pump for use in conjunction with a gas turbine engine is disclosed which includes a pump housing, a shrouded rotor member, and an inlet post member, wherein fluid is axially supplied along the pump centerline and then radially discharged at a first pressure to the interior chamber of the pump housing, at the base portion of vane elements associated with the rotor, thereby contacting the vane elements at a minimum angular velocity and angle of incidence. Also disclosed is a single bearing arrangement for eccentrically supporting a shrouded rotor member.

Abstract: A system is disclosed for draining residual fuel from the engine manifold of a gas turbine which includes an ejector having an inlet port for receiving high pressure fuel from a main fuel pump at engine shut-down, an outlet port and a suction port. The ejector defines a nozzle that extends between the inlet port and the outlet port for increasing the velocity of high pressure fuel flowing therethrough at engine shut-down so as to create suction at the suction port. A motive valve controls the flow of high pressure fuel between the main fuel pump and the inlet port of the ejector. The motive valve is configured for movement between a first position wherein high pressure fuel is directed from the main fuel pump to the engine manifold during engine start-up and operation, and a second position wherein high pressure fuel is directed from the main fuel pump to the inlet port of the ejector at engine shut-down.

Abstract: A centrifugal pump for a gas turbine engine, including a housing having a fluid inlet port for receiving fluid at an initial pressure and an interior chamber defining a central axis. An impeller disk disposed within the interior chamber of the housing and mounted for rotation about the central axis. The impeller disk defines first and second inlet areas and has a plurality of circumferentially spaced apart channels formed therein which extend from the inlet areas for conducting fluid from the inlet areas in a radially outward direction upon rotation of the impeller disk so as to increase the pressure of the fluid. A first collector is formed by the housing for receiving the fluid from the first inlet area via the channels at a first elevated pressure relative to the initial pressure and a second collector is formed by the housing for receiving fluid from the second inlet area via the channels at a second elevated pressure relative to the first elevated pressure.

Abstract: A fuel pump for use in conjunction with a gas turbine engine is disclosed which includes a pump housing, a shrouded rotor member, and an inlet post member, wherein fluid is axially supplied along the pump centerline and then radially discharged at a first pressure to the interior chamber of the pump housing, at the base portion of vane elements associated with the rotor, thereby contacting the vane elements at a minimum angular velocity and angle of incidence. Also disclosed is a single bearing arrangement for eccentrically supporting a shrouded rotor member.

Abstract: The fuel pumping system for delivering fuel to an engine includes a fuel transfer circuit for directing fuel from a fuel supply tank to the engine, a fuel boost pump, a main fuel pump and an accumulator device positioned along the transfer circuit between the boost pump and the engine for accumulating fuel and vapor so as to provide a reserve supply of fuel to the engine while minimizing the amount of undissolved vapor delivered to the engine. The system includes a return passage communicating, at one end, with the accumulator and at an opposite end with the fuel transfer circuit upstream of the boost pump for directing fuel and vapor from the accumulator into the transfer circuit.

Abstract: A unified fuel pump assembly combines a vane-type pump and a booster stage for the inlet of the vane-type pump, in a unitary structure to substantially reduce "windage" losses caused by relatively moving parts. The unified structure also includes an electric motor subassembly to provide motive power, and a liquid ring pump, which helps to process air bubbles through the fuel pump, is coupled to the electric motor rotor to further avoid "windage" losses. The vane type pump relies on the use of a central shaft capable of having a substantially uniform and relatively large diameter from end to end.