Abstract: A centrifugal pump and an impeller thereof are provided. The impeller defines an outer peripheral edge which includes a plurality of serrations circumferentially thereon. The plurality of serrations are configured such that additional power and momentum are transferred to a working fluid of the pump, which results in an additional pressure rise in the working fluid at relatively low flow rates of the centrifugal pump.

Abstract: A fuel system incorporating a boost pump unit, a boost pump unit and method of pumping fuel are provided. The fuel system and boost pump unit are preferably self-priming and do not utilize an airframe mounted pump for supplying fuel for an aircraft combustor. The boost pump unit includes a liquid ring pump and an air/fuel separator. The air/fuel separator has an inlet and first and second outlet ports. The inlet is operably fluidly coupled to an outlet of the liquid ring pump. The air/fuel separator has an arcuate flow path. The first outlet port is in fluid communication with a radially outer portion of the arcuate flow path and the second outlet port is in fluid communication with a radially inner portion of the arcuate flow path. A return line connected to the first outlet port is configured to return fuel to the liquid ring pump.

Abstract: A centrifugal pump and an impeller thereof are provided. The impeller defines an outer peripheral edge which includes a plurality of serrations circumferentially thereon. The plurality of serrations are configured such that additional power and momentum are transferred to a working fluid of the pump, which results in an additional pressure rise in the working fluid at relatively low flow rates of the centrifugal pump.

Abstract: A gear pump and gear pump housing are provided. The gear pump housing includes an inner wall and an outer wall. The inner wall defines an inner pumping cavity having a pumping cavity inlet and a pumping cavity outlet. The outer wall surrounds at least part of the inner wall. The outer wall being spaced apart from the outer wall defining a pressure cavity between the inner and outer walls. The pumping cavity outlet is in fluid communication with the pressure cavity. As such, the pressure cavity may be supplied with high pressure fluid that is pumped. The gear pump includes a pair of pumping gears between the pumping cavity inlet and pumping cavity outlet.

Abstract: A gear pump and gear pump housing are provided. The gear pump housing includes an inner wall and an outer wall. The inner wall defines an inner pumping cavity having a pumping cavity inlet and a pumping cavity outlet. The outer wall surrounds at least part of the inner wall. The outer wall being spaced apart from the outer wall defining a pressure cavity between the inner and outer walls. The pumping cavity outlet is in fluid communication with the pressure cavity. As such, the pressure cavity may be supplied with high pressure fluid that is pumped. The gear pump includes a pair of pumping gears between the pumping cavity inlet and pumping cavity outlet.

Abstract: A fuel system incorporating a boost pump unit, a boost pump unit and method of pumping fuel are provided. The fuel system and boost pump unit are preferably self-priming and do not utilize an airframe mounted pump for supplying fuel for an aircraft combustor. The boost pump unit includes a liquid ring pump and an air/fuel separator. The air/fuel separator has an inlet and first and second outlet ports. The inlet is operably fluidly coupled to an outlet of the liquid ring pump. The air/fuel separator has an arcuate flow path. The first outlet port is in fluid communication with a radially outer portion of the arcuate flow path and the second outlet port is in fluid communication with a radially inner portion of the arcuate flow path. A return line connected to the first outlet port is configured to return fuel to the liquid ring pump.

Abstract: A flow sensing dual pump switching system and method are provided that control the supply of fuel from a dual pump fuel system to a fuel metering unit. The system senses bypass pressure from the fuel metering unit to control the differential pressurization of the second pump. As the bypass is reduced, the pressure of the second pump is increased so that it may be added to that of the first pump to supply the increased fuel consumption needs of an engine. As the fuel consumption needs decrease, the flow from the second pump added to the first pump is reduced and the differential pressure of the second pump is similarly reduced. If the bypass pressure remains high, the switching system disconnects the output of the second pump from that of the first in favor of bypassing the flow to its input to reduce its differential pressure and conserve energy.

Abstract: An impeller for a centrifugal pump that includes a disk-shaped shroud having a central axis, a front surface, a rear surface, and a circular perimeter, and a hub at the center of the shroud, the hub having an axial bore. The impeller further includes a first set of vanes on the front surface of the shroud, the first set of vanes extending radially inward from the perimeter towards the hub, a second set of vanes on the rear surface of the shroud, the second set of vanes extending radially inward from the perimeter towards the hub, a balancing area on the rear surface of the shroud, the balancing area extending radially outward from the hub, and a number of openings in the shroud, the number of openings configured to allow a fluid to pass from one side of the shroud to the other.

Abstract: A flow sensing dual pump switching system and method are provided that control the supply of fuel from a dual pump fuel system to a fuel metering unit. The system senses bypass pressure from the fuel metering unit to control the differential pressurization of the second pump. As the bypass is reduced, the pressure of the second pump is increased so that it may be added to that of the first pump to supply the increased fuel consumption needs of an engine. As the fuel consumption needs decrease, the flow from the second pump added to the first pump is reduced and the differential pressure of the second pump is similarly reduced. If the bypass pressure remains high, the switching system disconnects the output of the second pump from that of the first in favor of bypassing the flow to its input to reduce its differential pressure and conserve energy.

Abstract: An impeller for a centrifugal pump that includes a disk-shaped shroud having a central axis, a front surface, a rear surface, and a circular perimeter, and a hub at the center of the shroud, the hub having an axial bore. The impeller further includes a first set of vanes on the front surface of the shroud, the first set of vanes extending radially inward from the perimeter towards the hub, a second set of vanes on the rear surface of the shroud, the second set of vanes extending radially inward from the perimeter towards the hub, a balancing area on the rear surface of the shroud, the balancing area extending radially outward from the hub, and a number of openings in the shroud, the number of openings configured to allow a fluid to pass from one side of the shroud to the other.

Abstract: A system for automatically transferring the fuel from one or more engine fuel manifolds directly to the engine fuel tank(s) during engine shutdown using an ejector pump has been presented. A checkvalve, which may be integrated with the ejector pump, is also used. A metering valve initiates fuel flow shutoff and is used in the draining of the fuel manifolds, thereby eliminating the need for an additional solenoid dedicated mainly to the shutoff function. The shutoff and pressurizing valve provides flow division between manifolds and manifold drain for systems having multiple manifolds. The bypass valve is used to turn the motive flow and/or manifold drain functions on and off as a function of engine speed at start and shutdown.

Abstract: A system for automatically transferring the fuel from one or more engine fuel manifolds directly to the engine fuel tank(s) during engine shutdown using an ejector pump has been presented. A checkvalve, which may be integrated with the ejector pump, is also used. A metering valve initiates fuel flow shutoff and is used in the draining of the fuel manifolds, thereby eliminating the need for an additional solenoid dedicated mainly to the shutoff function. The shutoff and pressurizing valve provides flow division between manifolds and manifold drain for systems having multiple manifolds. The bypass valve is used to turn the motive flow and/or manifold drain functions on and off as a function of engine speed at start and shutdown.

Abstract: A system for automatically transferring the fuel from one or more engine fuel manifolds directly to the engine fuel tank(s) during engine shutdown using an ejector pump has been presented. A checkvalve, which may be integrated with the ejector pump, is also used. A metering valve initiates fuel flow shutoff and is used in the draining of the fuel manifolds, thereby eliminating the need for an additional solenoid dedicated mainly to the shutoff function. The shutoff and pressurizing valve provides flow division between manifolds and manifold drain for systems having multiple manifolds. The bypass valve is used to turn the motive flow and/or manifold drain functions on and off as a function of engine speed at start and shutdown.

Abstract: A system for automatically transferring the fuel from one or more engine fuel manifolds directly to the engine fuel tank(s) during engine shutdown using an ejector pump has been presented. A checkvalve, which may be integrated with the ejector pump, is also used. A metering valve initiates fuel flow shutoff and is used in the draining of the fuel manifolds, thereby eliminating the need for an additional solenoid dedicated mainly to the shutoff function. The shutoff and pressurizing valve provides flow division between manifolds and manifold drain for systems having multiple manifolds. The bypass valve is used to turn the motive flow and/or manifold drain functions on and off as a function of engine speed at start and shutdown.

Abstract: A system for automatically transferring the fuel from one or more engine fuel manifolds directly to the engine fuel tank(s) during engine shutdown using an ejector pump has been presented. A checkvalve, which may be integrated with the ejector pump, is also used. A metering valve initiates fuel flow shutoff and is used in the draining of the fuel manifolds, thereby eliminating the need for an additional solenoid dedicated mainly to the shutoff function. The shutoff and pressurizing valve provides flow division between manifolds and manifold drain for systems having multiple manifolds. The bypass valve is used to turn the motive flow and/or manifold drain functions on and off as a function of engine speed at start and shutdown.