Centrifugal fuel pump with variable pressure control

Patent metadata

Field	Value
Publication number	US-9897054-B2
Application number	US-201514597938-A
Country	US
Kind code	B2
Filing date	Jan 15, 2015
Priority date	Jan 15, 2015
Publication date	Feb 20, 2018
Grant date	Feb 20, 2018

Abstract

A fuel flow control system includes a centrifugal pump, a gas inlet valve, and a control. The centrifugal pump has a fuel inlet, a gas inlet, and an outlet. The gas inlet valve is disposed upstream of the gas inlet and is responsive to valve position commands to move between a closed position, in which inert gas is prevented from flowing into the gas inlet, and a plurality of open positions, in which inert gas may flow into the gas inlet. The control is coupled to the gas inlet valve and is configured to supply the valve position commands to the gas inlet valve to command the gas inlet valve to selectively move to the closed position, such that the centrifugal pump is configured to operate as a fuel pump, or any open position, such that the centrifugal pump is configured to operate as a fuel-gas mixer.

First claim

What is claimed is:

1. A fuel flow control system, comprising:
a centrifugal pump having an impeller, a fuel inlet, a gas inlet, and an outlet, the impeller including a central section and a plurality of impeller blades that extend radially away from the central section, each impeller blade including a leading edge and a trailing edge;
a gas inlet valve disposed upstream of the gas inlet and responsive to valve position commands to move between a closed position, in which inert gas is prevented from flowing into the gas inlet, and a plurality of open positions, in which inert gas may flow into the gas inlet; and
a control coupled to the gas inlet valve and configured to supply the valve position commands to the gas inlet valve to command the gas inlet valve to selectively move to the closed position or one of the plurality of open positions,
wherein:
the impeller further includes a plurality of internal gas flow channels formed in the impeller, each internal gas flow channel in fluid communication with the gas inlet and including a gas inlet port, a gas outlet port, and a flow passage, each gas inlet port formed in the central section, each gas outlet port formed in the impeller and disposed adjacent a trailing edge of a different impeller blade, each flow passage formed entirely within the impeller and extending between its gas inlet port and its gas outlet port,
in the closed position, the centrifugal pump is configured to operate as a fuel pump,
in any one of the open positions, the centrifugal pump is configured to operate as a fuel-gas mixer,
discharge pressure at the outlet of the centrifugal pump varies with inert gas flow into the gas inlet, and
the control is further configured to supply the valve commands to the gas inlet valve to predictably control the discharge pressure at the outlet of the centrifugal pump.

2. The system of claim 1 , wherein the centrifugal pump is adapted to receive a drive torque and is configured, upon receipt thereof, to draw fuel into the fuel inlet and:
(i) when the gas inlet valve is in the closed position, to discharge only fuel from the outlet, and
(ii) when the gas inlet valve is in any one of the open positions, to receive inert gas injected into the gas inlet, mix the fuel and inert gas to produce a fuel-gas mixture, and discharge the fuel-gas mixture from the outlet.

3. The system of claim 1 , wherein the gas inlet is configured such that inert gas supplied thereto is discharged into the centrifugal pump between the fuel inlet and the outlet.

4. The system of claim 1 , wherein the centrifugal pump comprises:
an impeller shaft having a central bore formed therein and an outer surface, the impeller shaft adapted to couple to a drive shaft;
an impeller formed on the impeller shaft;
an inducer formed on the impeller shaft and disposed upstream of the impeller; and
a plurality of gas flow channels formed in the impeller shaft and extending between the central bore and the outer surface, each gas flow channel disposed between the inducer and the impeller and in fluid communication with the gas inlet.

5. The system of claim 1 , wherein the centrifugal pump comprises:
a pump housing having the gas inlet formed therein; and
an impeller rotationally mounted within the pump housing, the impeller disposed downstream of the gas inlet.

6. A fuel flow control system, comprising:
a centrifugal pump having an impeller, a fuel inlet, a gas inlet, and an outlet, the impeller including a central section and a plurality of impeller blades that extend radially away from the central section, each impeller blade including a leading edge and a trailing edge, the centrifugal pump adapted to receive a drive torque and configured, upon receipt thereof, to draw fuel into the fuel inlet;
a gas inlet valve disposed upstream of the gas inlet and responsive to valve position commands to move between a closed position, in which inert gas is prevented from flowing into the gas inlet, and a plurality of open positions, in which inert gas may flow into the gas inlet; and
a control coupled to the gas inlet valve and configured to supply the valve position commands to the gas inlet valve to command the gas inlet valve to selectively move to the closed position or one of the plurality of open positions,
wherein:
(i) when the gas inlet valve is in the closed position, the centrifugal pump is further configured to discharge only fuel from the outlet,
(ii) when the gas inlet valve is in any one of the open positions, the centrifugal pump is further configured to receive inert gas injected into the gas inlet, mix the fuel and inert gas to produce a fuel-gas mixture, and discharge the fuel-gas mixture from the outlet,
the impeller further includes a plurality of internal gas flow channels formed in the impeller, each internal gas flow channel in fluid communication with the gas inlet and including a gas inlet port, a gas outlet port, and a flow passage, each gas inlet port formed in the central section, each gas outlet port formed in the impeller and disposed adjacent a trailing edge of a different impeller blade, each flow passage formed entirely within the impeller and extending between its gas inlet port and its gas outlet port.

7. The system of claim 6 , wherein:
when the gas inlet valve is in the closed position, the centrifugal pump is configured to operate as a fuel pump, and
when the gas inlet valve is in one of the plurality of open positions, the centrifugal pump is configured to operate as a fuel-gas mixer.

8. The system of claim 6 , wherein discharge pressure at the outlet of the centrifugal pump varies with inert gas flow into the gas inlet.

9. The system of claim 8 , wherein the control is further configured to supply the valve commands to the gas inlet valve to thereby control the discharge pressure at the outlet of the centrifugal pump.

10. The system of claim 6 , wherein the gas inlet is configured such that inert gas supplied thereto is discharged into the centrifugal pump between the fuel inlet and the outlet.

11. The system of claim 6 , wherein the centrifugal pump further comprises:
an impeller shaft having the impeller formed thereon, the impeller shaft further having a central bore formed therein and an outer surface, the impeller shaft adapted to couple to a drive shaft;
an inducer formed on the impeller shaft and disposed upstream of the impeller; and
a plurality of gas flow channels formed in the impeller shaft and extending between the central bore and the outer surface, each gas flow channel disposed between the inducer and the impeller and in fluid communication with the gas inlet.

12. The system of claim 6 , wherein the centrifugal pump comprises:
a pump housing having the gas inlet formed therein; and
an impeller rotationally mounted within the pump housing, the impeller disposed downstream of the gas inlet.

13. A fuel flow control system, comprising:
a centrifugal pump having a fuel inlet, a gas inlet, and an outlet;
a gas inlet valve disposed upstream of the gas inlet and responsive to valve position commands to move between a closed position, in which inert gas is prevented from flowing into the gas inlet, and a plurality of open positions, in which inert gas may flow into the gas inlet; and
a control coupled to the gas inlet valve and configured to supply the valve position commands to the gas inlet valve to command the gas inlet valve to selectively move to the closed position or one of the plurality of open positions, to thereby control discharge pressure at the outlet of the centrifugal pump,
wherein the centrifugal pump further comprises:
an impeller shaft having a central

Assignees

• Honeywell Int Inc

Inventors

• Lo Charles
• Laboda Dan

Classifications

• F04D17/08

  Centrifugal pumps · CPC title

• F02M59/36 Primary

  by variably-timed valves controlling fuel passages {to pumping elements or overflow passages} · CPC title

• F04D31/00

  Pumping liquids and elastic fluids at the same time · CPC title

• B64D37/32

  Safety measures not otherwise provided for, e.g. preventing explosive conditions · CPC title

• F04D29/2277 Primary

  for increasing NPSH or dealing with liquids near boiling-point · CPC title