Unitary sliding vane compressor-expander and electrical generation system

• US 6,589,033 B1
• Filed: 09/29/2000
• Issued: 07/08/2003
• Est. Priority Date: 09/29/2000
• Status: Expired due to Fees

• Current Assignee: Phoenix Analysis And Design Technologies, Inc.
• Original Assignee: Phoenix Analysis And Design Technologies, Inc.
• Inventors: Miller, Eric R., Addink, Jason L., Rogers, Bradley B., Rosales, Jorge L., Johnson, Mark C.
• Primary Examiner(s): Denion, Thomas
• Assistant Examiner(s): Trieu, Theresa
• Application Number:
  US09/678,368
• Time in Patent Office: 1,012 Days
• Field of Search: 418/13, 418/152, 418/179, 418/158, 418/DIG.1, 418/82, 418/268, 429/34, 429/26, 429/13, 429/17, 621/16, 624/98, 624/02, 604/19
• US Class Current: 418/13
• CPC Class Codes: F01C 11/004 and of complementary function, e.g. internal combustion engine with supercharger
• CPC Class Codes: F04C 18/3446 the inner and outer member being in contact along more than one line or surface
• CPC Class Codes: F04C 23/00 Combinations of two or more pumps, each being of rotary-piston or oscillating-piston type, specially adapted for elastic fluids; Pumping installations specially adapted for elastic fluids; Multi-stage pumps specially adapted for elastic fluids F04C25/00 takes precedence
• CPC Class Codes: F04C 23/003 having complementary function
• CPC Class Codes: F04C 25/00 Adaptations of pumps for special use of pumps for elastic fluids

Abstract

The present invention provides a unitary sliding-vane type compressor-expander comprising a housing with a compressor inlet and outlet, and an expander inlet and outlet. A single rotor is disposed therein defining in cooperation with the housing a compression chamber on one side and an expansion chamber on the opposite side. The rotor includes a plurality of regularly spaced vanes slidingly disposed in slots about the periphery of the rotor. The bottoms of the vane slots may be vented through a passage in the housing to the inlet air, or alternatively through a groove between the vane and vane slot to the compression or exhaust chambers. Permanent magnets are used in the vanes and housing to increase or decrease the contact force between the vane tip and housing. An integral condenser-humidifier is provided in the path of the expanded gas exhausting from the turbine outlet for condensing water out of the expanded gas and returning the condensed water to the compressor-expander. The integral condenser may comprise a substantially vertically oriented spout or an internal chamber. In another embodiment of the invention an electrical generation system is provided comprising a unitary sliding vane type compressor-expander in combination with a fuel cell. The compressor portion of the compressor-expander provides compressed air to an oxidant inlet of the fuel cell, and the spent oxidant exhaust from the fuel cell is expanded through the expander portion of the compressor-expander.

Claims

1. A fuel cell electrical generation system comprising:

a unitary sliding vane type compressor-expander for improving the efficiency of the system, comprising;

a housing having a compressor side with a compressor inlet port and a compressor outlet port, and an expander side with an expander inlet port and an expander outlet port;

a cylindrical rotor disposed within the housing and having a plurality sliding vanes disposed in slots around an outer periphery thereof, wherein the vanes are configured to slide inward and outward along the slots upon rotation of the rotor, thereby maintaining contact with an inner contoured surface of the housing and simultaneously compressing oxidant gas on the compressor side of the housing and expanding oxidant gas on the expander side of the housing;

a fuel cell for generating output electrical power having an oxidant inlet connected to the compressor outlet port of the compressor-expander for receiving pre-compressed oxidant gas therefrom, an oxidant outlet connected to the expander inlet port of the compressor-expander for exhausting compressed oxidant thereto, a fuel inlet for introducing fuel to react with the oxidant gas, and a fuel exhaust for exhausting reacted fuel;

a motor, powered by electricity derived from the fuel cell electrical generation system, having an output shaft connected to the cylindrical rotor of the compressor-expander for rotationally driving the cylindrical rotor to cause the simultaneous compression and expansion of oxidant gas in the compressor-expander.

2. The fuel cell electrical generation system of claim 1, wherein the bottoms of the vane slots are vented.

3. The fuel cell electrical generation system of claim 2, wherein the bottom of one vane slot is vented to the bottom of at least one other vane slot.

4. The electrical generation system of claim 3, wherein the bottom of at least one vane slot is vented to at least one of the inlet and outlet ports.

5. The fuel cell electrical generation system of claim 1, further comprising an integral exhaust gas condenser-humidifier.

6. The fuel cell electrical generation system of claim 5, wherein the integral condenser comprises one of a vertically oriented spout, or an internal chamber.

7. The fuel cell electrical generation system of claim 1, further comprising:

a permanent magnet in at least one of the vanes; and

at least one stationary magnet in the housing.

8. The fuel cell electrical generation system of claim 1, wherein the compressor-expander housing is made of a material selected from the group consisting of:

stainless steel, aluminum, aluminum with an anodize coating, aluminum with a TEFLON impregnated anodize coating, or ceramic.

9. The fuel cell electrical generation system of claim 1, wherein the compressor-expander rotor is made of a material selected from the group consisting of:

stainless steel, aluminum, aluminum with an anodize coating, aluminum with a TEFLON impregnated anodize coating, or ceramic.

10. A unitary sliding vane type compressor-expander, comprising:

a compressor portion with a compressor inlet and a compressor outlet;

an expander portion with an expander inlet and an expander outlet; and

an integral condenser-humidifier disposed in fluid communication with the expander outlet for condensing water out of the expanded gas and returning the condensed water directly to the expander outlet.

11. The compressor expander of claim 10, further comprising:

a housing; and

a single rotor with a plurality of sliding vanes in slots defining in cooperation with the housing a compression chamber in the compressor portion and an expansion chamber in the expander portion of the compressor-expander.

12. The unitary compressor-expander of claim 11, wherein the bottom of the vane slots in the rotor are vented.

13. The unitary compressor-expander of claim 12, wherein the bottom of at least one slot is vented to the compression chamber.

14. The unitary compressor-expander of claim 12, wherein the bottom of the vane slots are vented through a groove between the face of the vane and the slot.

15. The unitary compressor-expander of claim 11, wherein the bottom of at least one vane slot is vented to at least one of the inlet and outlet ports.

16. The unitary compressor-expander of claim 11, further comprising:

a permanent magnet in at least one of the vanes; and

at least one stationary magnet in the housing.

17. The compressor-expander of claim 11, wherein the housing is made of a material selected from the group consisting of:

stainless steel;

aluminum;

aluminum with an anodize coating;

aluminum with a TEFLON impregnated anodize coating;

or ceramic.

18. The compressor-expander of claim 11, wherein the rotor is made of a material selected from the group consisting of:

stainless steel;

aluminum;

aluminum with an anodize coating;

aluminum with a TEFLON impregnated anodize coating;

or ceramic.

19. The unitary compressor-expander of claim 10, wherein the integral condenser is configured to allow condensed water to drain under the influence of gravity into the path of the vanes at the expander outlet.

20. The unitary compressor-expander of claim 10, wherein the integral condenser comprises a substantially vertical spout.

21. The unitary compressor-expander of claim 20, wherein the orientation of the vertical spout is adjustable relative to the compressor-expander.

22. The unitary compressor-expander of claim 10, wherein the integral condenser comprises an internal chamber.

23. A unitary compressor-expander comprising:

a housing having a compressor side with a compressor inlet and a compressor outlet, and an expander side with an expander inlet and an expander outlet;

a cylindrical rotor disposed within the housing and having a plurality sliding vanes disposed in slots around an outer periphery thereof, wherein the vanes are configured to slide outwardly along the slots upon rotation of the rotor, and sealingly contact an inner contoured surface of the housing;

a vane magnet in at least one of the vanes;

at least one stationary magnet in the housing disposed about the inner contacting surface, wherein the poles of the vane magnet are substantially aligned with the direction of the vane and its corresponding slot, and the poles of the at least one stationary magnet are substantially aligned with the vanes and slots as they pass by the stationary magnet, wherein a first one of said at least one stationary magnets is oriented to repel the vane magnet, and a second one of said at least one stationary magnets is oriented to attract the vane magnet.

24. A method for improving the efficiency of a fuel cell electrical generation system, comprising the steps of:

providing a fuel cell for generating output electrical power having an oxidant inlet, an oxidant outlet, a fuel inlet, and a fuel exhaust;

connecting a unitary vane type compressor-expander to the fuel cell, comprising;

a housing having a compressor side with a compressor inlet port and a compressor outlet port, and an expander side with an expander inlet port and an expander outlet port;

a cylindrical rotor disposed within the housing and having a plurality sliding vanes disposed in slots around an outer periphery thereof, wherein the vanes are configured to slide inward and outward along the slots upon rotation of the rotor, thereby maintaining contact with an inner contoured surface of the housing and simultaneously compressing oxidant gas on the compressor side of the housing and expanding oxidant gas on the expander side of the housing;

driving the unitary compressor expander with a motor, powered by electricity derived from the fuel cell electrical generation system, by means of an output shaft of the motor connected to the cylindrical rotor of the compressor-expander for rotationally driving the cylindrical rotor;

compressing air drawn from the compressor inlet on in the compressor side of the compressor-expander;

supplying the compressed air to an oxidant inlet of the fuel cell for reacting with fuel introduced through the fuel inlet; and

expanding the spent oxidant gas from the fuel cell across the expander side of the compressor-expander.

25. The method of claim 24, further comprising the steps of:

condensing water out of the expanded exhaust gas; and

carrying at least a portion of the condensed water by rotation of the rotor, across into the compressor side of the compressor-expander.

26. The method of claim 25, further comprising the step of providing a substantially vertical spout for performing the step of condensing water out of the expanded exhaust gas.

27. The method of claim 25, further comprising the step of providing an internal condensing chamber in the path of the expanded exhaust gas for performing the condensing step.