Heat transfer system with integrated evaporator and condenser

• US 9,182,177 B2
• Filed: 07/12/2012
• Issued: 11/10/2015
• Est. Priority Date: 07/12/2011
• Status: Active Grant

• Current Assignee: Flextronics America LLC (Flextronics International Limited)
• Original Assignee: Flextronics America LLC (Flextronics International Limited)
• Inventors: Shabany, Younes
• Primary Examiner(s): Ali, Mohammad M
• Assistant Examiner(s): Tanenbaum, Steve
• Application Number:
  US13/548,001
• Publication Number:
  US 20130042636A1
• Time in Patent Office: 1,216 Days
• Field of Search: 621/19, 622/592, 165/80.4, 16510433-10434, 165/104.26, 165/104.21, 165/185, 165/274, 361/679.52, 361/700, 361/679.54, 361/704, 361709-710
• US Class Current: 1/1
• CPC Class Codes: F28D 15/0233 the conduits having a particular shape, e.g. non-circular cross-section, annular F28D15/0241, F28D15/0266 take precedence
• CPC Class Codes: F28D 15/0266 with separate evaporating and condensing chambers connected by at least one conduit; Loop-type heat pipes; with multiple or common evaporating or condensing chambers F28D15/043 takes precedence
• CPC Class Codes: F28D 15/06 Control arrangements therefor
• CPC Class Codes: F28D 2021/0028 for cooling heat generating elements, e.g. for cooling electronic components or electric devices for cooling semiconductors H01L23/34, for cooling electric apparatus H05K7/20
• CPC Class Codes: H01L 23/427 Cooling by change of state, e.g. use of heat pipes by liquefied gas H01L23/445
• CPC Class Codes: H01L 2924/00 Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
• CPC Class Codes: H01L 2924/0002 Not covered by any one of groups H01L24/00, H01L24/00 and H01L2224/00

Abstract

Two phase heat transfer systems including integrated fluid transfer paths for exchange of a working fluid between an evaporator and condenser. Separate fluid transfer paths may be defined for communication of working fluid between the evaporator and condenser, wherein at least one of the fluid transfer paths is integrated with the evaporator and/or condenser. In one embodiment, both first and second fluid transfer paths are integrally provided to establish direct fluid communication between the evaporator and condenser to facilitate flow of vaporized and condensed working fluid respectively.

Claims

1. A heat transfer system, comprising:

an evaporator thermally engageable with a heat source and including an evaporator cavity holding a working fluid;

a condenser having a ceiling, a floor, one or more perimeter walls extending between the ceiling and the floor at the perimeter of the ceiling and the floor, one or more internal walls extending between the ceiling and the floor inside the perimeter walls, and a continuous condenser cavity between the ceiling, the floor, the perimeter walls and the internal walls, wherein the continuous condenser cavity is in fluid communication with the evaporator to receive vaporized working fluid from the evaporator, wherein the evaporator and the condenser are adjacent to each other such that a thin wall forms at least a portion of both the top surface of the evaporator cavity and the bottom surface of the continuous condenser cavity;

a first fluid transfer path extending from the evaporator to the condenser for movement of the vaporized working fluid from the evaporator to the condenser; and

a second fluid transfer path extending from the condenser to the evaporator for movement of condensed working fluid from the condenser to the evaporator, wherein the second fluid transfer path is separate from the first fluid transfer path;

wherein at least one of the first fluid transfer path or the second fluid transfer path is integrally defined by the evaporator or condenser, and further wherein the continuous condenser cavity extends laterally beyond the perimeter of the evaporator cavity, wherein the evaporator is sealed such that the working fluid is only able to exit the evaporator by entering the condenser.

2. The heat transfer system according to claim 1, wherein the evaporator is in direct fluid communication with the condenser via the first fluid transfer path integrally defined by at least one of the evaporator or the condenser.

3. The heat transfer system according to claim 2, wherein the condenser is in direct fluid communication with the evaporator via the second fluid transfer path integrally defined by at least one of the condenser and the evaporator.

4. The heat transfer system according to claim 1, further comprising:

an electronic component in thermal communication with the evaporator, wherein the electronic component generates heat in response to operation of the electronic component and comprises the heat source.

5. The heat transfer system according to claim 4, further comprising a fluid passage extending between the first fluid transfer path and the second fluid transfer path, wherein the fluid passage extends through the condenser.

6. The heat transfer system according to claim 5, wherein the fluid passage extends laterally beyond a lateral spatial extent of the evaporator.

7. The heat transfer system according to claim 6, wherein flow of the working fluid through the fluid passage comprises mass flow of the working fluid laterally beyond the lateral spatial extent of the evaporator.

8. The heat transfer system according to claim 6, wherein an internal surface area of the condenser is at least about twice as large as an internal surface area of the evaporator.

9. The heat transfer system according to claim 8, wherein a flow control establishes operational fluid flow of the working fluid from the first fluid transfer path, through the fluid passage, and to the second fluid transfer path.

10. The heat transfer system according to claim 9, wherein flow in a direction opposite the operational fluid flow is limited by the flow control.

11. The heat transfer system according to claim 4, wherein the working fluid comprises at least one of water, alcohol, or ammonia.

12. The heat transfer system according to claim 11, wherein the evaporator and the condenser are integrally constructed from a single portion of material.

13. The heat transfer system according to claim 12, wherein the material comprises aluminum or copper.

14. A system for cooling an electronic device, the electronic device operable to generate heat upon operation of the electronic device, the system comprising:

an evaporator provided in thermal communication with the electronic device, wherein the evaporator includes an evaporator cavity holding working fluid operable to absorb thermal energy transferred thereto from the electronic device;

a condenser having a ceiling, a floor, one or more perimeter walls extending between the ceiling and the floor at the perimeter of the ceiling and the floor, one or more internal walls extending between the ceiling and the floor inside the perimeter walls, and a continuous condenser cavity between the ceiling, the floor, the perimeter walls and the internal walls, wherein the continuous condenser cavity is in fluid communication with the evaporator and operable to receive vaporized working fluid from the evaporator, wherein the working fluid is vaporized as a result of the absorbing of thermal energy from the electronic device, wherein the evaporator and the condenser are adjacent to each other such that a thin wall forms at least a portion of both the top surface of the evaporator cavity and the bottom surface of the continuous condenser cavity, wherein the entirety of the continuous condenser cavity is located on a level above the bottom surface;

a first fluid transfer path extending from the evaporator to the condenser for movement of the vaporized working fluid from the evaporator to the condenser; and

a plurality of second fluid transfer paths each extending from the condenser to the evaporator for movement of condensed working fluid from the condenser to the evaporator, wherein the working fluid is condensed as a result of transfer of thermal energy from the working fluid to the condenser, and wherein the first fluid transfer path is separate from the second fluid transfer paths;

wherein at least one of the first fluid transfer path and the second fluid transfer path is integrally defined by the evaporator or condenser and the electronic device is outside of the evaporator cavity, and further wherein the continuous condenser cavity extends laterally beyond the perimeter of the evaporator cavity, wherein the evaporator is sealed such that the working fluid is only able to exit the evaporator by entering the condenser.

15. The system according to claim 14, further comprising a fluid passage extending between the first fluid transfer path and the second fluid transfer path, wherein the fluid passage at least in part extends laterally beyond a lateral spatial extent of the evaporator.

16. The system according to claim 15, further comprising a flow control for directing working fluid from the first fluid transfer path, through the fluid passage, and to the second fluid transfer path in that order.