A regenerative pump includes a housing defining a cavity having a fluid inlet arrangement and fluid outlet arrangement, and a channel having an open volume extending between the fluid inlet arrangement and the fluid outlet arrangement. A rotatable shaft extends into the housing. An impeller is mounted to the shaft within the cavity and has a plurality of vanes spaced circumferentially around the axis and opening into the channel. An arm arrangement at least partially defines walls of the channel. The arm arrangement is radially movable to vary the volume of the channel. Enlarging the volume of the channel inhibits regenerative circulatory flow during pumping and limits the pressure generated.

A liquid fuel system for an aircraft engine includes a first fuel supply conduit hydraulically connected to a fuel source, a second fuel supply conduit hydraulically connected to the engine, a fuel return conduit hydraulically connected to the second fuel supply conduit, and a fuel pump. The fuel pump has a main inlet hydraulically connected to the first fuel supply conduit, an outlet hydraulically connected to the second fuel supply conduit, and an intermediate inlet hydraulically connected to the fuel return conduit. The intermediate inlet is located between the main inlet and the outlet and in use has a pressure between the main inlet pressure and the outlet pressure. A method of supplying a liquid fuel to an aircraft engine is also described.

A rotodynamic pump for pumping a fluid includes an impeller, a housing surrounding the impeller, and a pressure regulating mechanism. The pressure regulating mechanism is configured to adjust the clearance between the impeller and the impeller housing to regulate pressure of the fluid downstream of the impeller. A method of regulating the delivery pressure is also disclosed.

A method of controlling a delivery pressure of an aircraft engine fuel system includes operating a rotodynamic fuel pump hydraulically connected to the fuel system to pump a fluid from an inlet of the rotodynamic pump and out of an outlet of the rotodynamic pump for delivery to the fuel system. The method further includes varying an angular relationship between the inlet and the outlet of the pump to control the delivery pressure. An aircraft engine fuel system and a rotodynamic pump are also described.

A transfer pump includes a housing defining an inlet and an outlet. A main pump path and a bypass path disposed between the inlet and the outlet. A motor is in fluid communication with the main pump path and is configured to be energized to move a fluid through the main pump path and the bypass path. The fluid movement being indicative of a non-siphoning condition occurring between the inlet and the outlet. A flow sensor is disposed in fluid communication with the bypass path and being configured to generate a flow rate signal indicative of a flow rate of fluid in the bypass path. A controller in communication with the flow sensor for receiving the flow rate signal and being configured to de-energize the motor when the flow rate signal satisfies a first flow rate threshold indicative of a siphoning condition occurring between the inlet and the outlet.

A centrifugal pump includes a selectable regenerative style pumping element, including a regenerative pump rotor and at least one side wall flow channel formed by a rotating disc. The regenerative pumping element is selectable between a first state in which the disc does not rotate with the impeller and a second state in which the disc rotates with the impeller.

A method of controlling a delivery pressure of an aircraft engine fuel system includes operating a rotodynamic fuel pump hydraulically connected to the fuel system to pump a fluid from an inlet of the rotodynamic pump and out of an outlet of the rotodynamic pump for delivery to the fuel system. The method further includes varying an angular relationship between the inlet and the outlet of the pump to control the delivery pressure. An aircraft engine fuel system and a rotodynamic pump are also described.

A rotodynamic pump for pumping a fluid includes an impeller, a housing surrounding the impeller, and a pressure regulating mechanism. The pressure regulating mechanism is configured to adjust the clearance between the impeller and the impeller housing to regulate pressure of the fluid downstream of the impeller. A method of regulating the delivery pressure is also disclosed.

A liquid fuel system for an aircraft engine includes a first fuel supply conduit hydraulically connected to a fuel source, a second fuel supply conduit hydraulically connected to the engine, a fuel return conduit hydraulically connected to the second fuel supply conduit, and a fuel pump. The fuel pump has a main inlet hydraulically connected to the first fuel supply conduit, an outlet hydraulically connected to the second fuel supply conduit, and an intermediate inlet hydraulically connected to the fuel return conduit. The intermediate inlet is located between the main inlet and the outlet and in use has a pressure between the main inlet pressure and the outlet pressure. A method of supplying a liquid fuel to an aircraft engine is also described.

A motor control device includes: a rotation control determination unit configured to determine whether a motor rotation control to rotate the motor fails; a parameter calculation unit configured to calculate a control failure frequency parameter having a correlation with a frequency of failure in the motor rotation control based on a determination result by the rotation control determination unit; an abnormality determination unit configured to determine whether an abnormality has occurred in the motor based on the control failure frequency parameter; and a stop suppression unit configured to suppress stop of rotation of the motor by changing a motor control parameter to perform the motor rotation control when the abnormality determination unit determines that an abnormality has occurred in the motor.