Abstract:
A gas turbine engine fuel supply system includes a primary gear pump, a secondary gear pump, and a pump bypass valve. The primary gear pump always actively delivers fuel to the downstream fuel system, and is sized to supply 100% of the burn flow needed at a select low demand condition. The secondary gear pump is sized to make up the remainder of the flow at high demand conditions, and actively delivers fuel to the downstream fuel system only during those conditions. To supply discharge fuel pressures in excess of gear pump capability, a supercharger pump is disposed upstream of the primary and secondary gear pumps. The pump bypass valve is configured to regulate fuel pressure at the primary gear pump outlet to one of a plurality of preset differential pressures above one of a plurality of fuel load pressures and prevents reverse pressurization of the gear pumps.
Abstract:
A gas turbine engine fuel supply system includes a primary gear pump and a secondary gear pump. The primary gear pump always actively delivers fuel to the downstream fuel system, and is sized to supply 100% of the burn flow needed at a select low demand condition. The secondary gear pump is sized to make up the remainder of the flow at high demand conditions, and actively delivers fuel to the downstream fuel system only during those conditions. To supply discharge fuel pressures in excess of gear pump capability, a supercharger pump is disposed upstream of the primary and secondary gear pumps. The supercharger pump is preferably activated only during high demand conditions as an additional energy conservation measure.
Abstract:
A gas turbine engine fuel supply system includes a primary gear pump and a secondary gear pump. The primary gear pump always actively delivers fuel to the downstream fuel system, and is sized to supply 100% of the burn flow needed at a select low demand condition. The secondary gear pump is sized to make up the remainder of the flow at high demand conditions, and actively delivers fuel to the downstream fuel system only during those conditions. To supply discharge fuel pressures in excess of gear pump capability, a supercharger pump is disposed upstream of the primary and secondary gear pumps. The supercharger pump is preferably activated only during high demand conditions as an additional energy conservation measure.
Abstract:
A fuel metering system includes a metering valve having a first inlet fluidly coupled to a source of fluid at a first pressure, a second inlet, a first outlet and a second outlet. The metering valve includes a slot, and a valve body movable to control an amount of fluid supplied to the first and second outlet. The fuel metering system includes a servo valve fluidly coupled to the second inlet and to a second source of fluid at a second pressure. The servo valve is in fluid communication with the second inlet and a body of the servo valve is movable to supply a fluid to move the valve body. The slot is configured to variably restrict the flow of the fluid through the second outlet to balance a force applied by a biasing member. The fuel metering system includes a fixed flow restriction downstream of the second outlet.
Abstract:
A fuel metering system includes a metering valve having a first inlet fluidly coupled to a source of fluid at a first pressure, a second inlet, a first outlet and a second outlet. The metering valve includes a slot, and a valve body movable to control an amount of fluid supplied to the first and second outlet. The fuel metering system includes a servo valve fluidly coupled to the second inlet and to a second source of fluid at a second pressure. The servo valve is in fluid communication with the second inlet and a body of the servo valve is movable to supply a fluid to move the valve body. The slot is configured to variably restrict the flow of the fluid through the second outlet to balance a force applied by a biasing member. The fuel metering system includes a fixed flow restriction downstream of the second outlet.
Abstract:
Embodiments of a combined overspeed and fuel stream selector system are provided. In an embodiment, the assembly includes a conduit network, a Discharge Select Valve (DSV), and a shutoff valve. The DSV is fluidly coupled to a primary fuel inlet, a secondary fuel inlet, and a primary fuel outlet included in the conduit network. The shutoff valve is fluidly coupled between the primary fuel inlet and the primary fuel outlet. In a standard operation mode, the shutoff valve is maintained in an open position, while fuel received at the primary fuel inlet is directed through the shutoff valve, through the DSV, and to the primary fuel inlet. Conversely, in a backup operation mode, the shutoff valve is closed to block fuel flow from the primary fuel inlet to the primary fuel outlet, while the DSV directs fuel flow received at the secondary fuel inlet to the primary fuel outlet.
Abstract:
Embodiments of a combined overspeed and fuel stream selector system are provided. In an embodiment, the assembly includes a conduit network, a Discharge Select Valve (DSV), and a shutoff valve. The DSV is fluidly coupled to a primary fuel inlet, a secondary fuel inlet, and a primary fuel outlet included in the conduit network. The shutoff valve is fluidly coupled between the primary fuel inlet and the primary fuel outlet. In a standard operation mode, the shutoff valve is maintained in an open position, while fuel received at the primary fuel inlet is directed through the shutoff valve, through the DSV, and to the primary fuel inlet. Conversely, in a backup operation mode, the shutoff valve is closed to block fuel flow from the primary fuel inlet to the primary fuel outlet, while the DSV directs fuel flow received at the secondary fuel inlet to the primary fuel outlet.
Abstract:
A gas turbine engine fuel supply system includes a primary gear pump, a secondary gear pump, and a pump bypass valve. The primary gear pump always actively delivers fuel to the downstream fuel system, and is sized to supply 100% of the burn flow needed at a select low demand condition. The secondary gear pump is sized to make up the remainder of the flow at high demand conditions, and actively delivers fuel to the downstream fuel system only during those conditions. To supply discharge fuel pressures in excess of gear pump capability, a supercharger pump is disposed upstream of the primary and secondary gear pumps. The pump bypass valve is configured to regulate fuel pressure at the primary gear pump outlet to one of a plurality of preset differential pressures above one of a plurality of fuel load pressures and prevents reverse pressurization of the gear pumps.