Heat exchanger for fuel cell system

• US 20020104645A1
• Filed: 02/05/2002
• Published: 08/08/2002
• Est. Priority Date: 02/07/2001
• Status: Active Grant

• Current Assignee: Calsonic Kansei Corporation
• Original Assignee: Calsonic Kansei Corporation
• Inventors: Yoshioka, Hiroki, Yoshida, Kazue
• Granted Patent: US 6,880,628 B2
• Time in Patent Office: Days
• US Class Current: 165/166
• CPC Class Codes: F28D 2021/0043 for fuel cells
• CPC Class Codes: F28D 9/0043 the plates having openings therein for circulation of at least one heat-exchange medium from one conduit to another
• CPC Class Codes: F28D 9/0056 with U-flow or serpentine-flow inside conduits; with centrally arranged openings on the plates
• CPC Class Codes: F28D 9/0075 the plates having openings therein for circulation of the heat-exchange medium from one conduit to another
• CPC Class Codes: F28F 13/08 by varying the cross-section of the flow channels
• CPC Class Codes: F28F 2250/102 with change of flow direction
• CPC Class Codes: F28F 3/025 the means being corrugated, plate-like elements
• CPC Class Codes: F28F 3/04 the means being integral with the element
• CPC Class Codes: H01M 8/04007 related to heat exchange
• CPC Class Codes: H01M 8/04067 Heat exchange or temperature measuring elements, thermal insulation, e.g. heat pipes, heat pumps, fins
• CPC Class Codes: H01M 8/0612 from carbon-containing material
• CPC Class Codes: Y02E 60/50 Fuel cells

Abstract

A plurality of heat transfer tube elements 17 are laminated with outer fins disposed between the heat transfer tube elements 17 in order to form a core. A gas flows between the outer fins. A passage 24 allowing flow of a cooling medium in a direction orthogonal to the direction of gas flow is formed in each heat transfer tube element 17. The passage 24 has a large passage 31 having a large width disposed upstream with respect to the direction a of gas flow and a small passage group 33 comprising a plurality of small passages 32 being more narrow than the large passage 31 and being disposed downstream with respect to the direction of gas flow. This arrangement allows non-uniformity in the temperature distribution of a gas flow to be suppressed to a low level with a downsizing, low-weight and low-cost device.

Claims

1. A heat exchanger for use in a fuel cell system, the heat exchanger comprising:

heat transfer tube elements having an flat passage allowing flow of a cooling medium therein;

outer fins retained between adjacent the heat transfer tube elements allowing flow of a gas there through and

a core formed by laminating the heat transfer tube elements and the outer fins in order;

wherein

the gas flows through the outer fins in a direction orthogonal to the direction of cooling medium flow which flows in the passage in each heat transfer tube element; and

a passage in at least a section of the passage for cooling medium provided in each heat transfer tube element comprises a large passage and a small passage group disposed in parallel, the large passage having a large width and being provided upstream to the core with respect to the direction of gas flow, and the small passage group comprising a plurality of small passages being narrower than the large passage and being provided downstream of the core with respect to the direction of gas flow.

2. The heat exchanger as defined in claim 1, wherein the small passage group is formed by disposing corrugated inner fins in the cooling medium passage.

3. The heat exchanger as defined in claim 2, wherein the small passage group has a width corresponding to 20-40% of the total width of the cooling medium passage.

4. The heat exchanger as defined in claim 1, further comprising;

an inlet tank connected with the inlet of the cooling medium passage provided on one end of the heat transfer tube elements, and

an outlet tank connected with the outlet of the cooling medium passage provided on the other end of the heat transfer tube elements.

5. The heat exchanger as defined in claim 4, wherein the inlet tank and the outlet tank are formed in a section of the heat transfer tube elements by a through hole provided in a direction orthogonal to the direction of cooling medium flow.

6. The heat exchanger as defined in claim 1, wherein the direction of cooling medium flow inverts after flowing through a section of the cooling medium passage from one longitudinal end of the heat transfer tube elements to the other longitudinal end, and flows in the opposite direction to the above by flowing through the other cooling medium passage from one longitudinal end of the heat transfer tube elements to the other longitudinal end.

7. The heat exchanger as defined in claim 6, wherein an inlet tank connected to the inlet of a section of the cooling medium passage and an outlet tank connected to the outlet of the remaining cooling medium passage are disposed adjacently on one end of the heat transfer tube elements, and an intermediate tank connected with the entire cooling medium passage is disposed on the other end of the heat transfer tube elements.

8. The heat exchanger as defined in claim 7, wherein the intermediate tank, the inlet tank and the outlet tank are formed in a section of the heat transfer tube elements by a through hole provided in a direction orthogonal to the direction of cooling medium flow.

9. The heat exchanger as defined in claim 7, wherein the cooling medium passage connected to the inlet tank is disposed upstream of the core with respect to the direction of gas flow.

10. The heat exchanger as defined in claim 9, wherein a large passage and a small passage group are disposed in parallel in the cooling medium passage disposed upstream.

11. The heat exchanger as defined in claim 1, wherein at least one face of the outer fin is coated with a catalyst.