Heat exchange – With retainer for removable article – Electrical component
Reexamination Certificate
1998-10-29
2001-10-30
Flanigan, Allen (Department: 3743)
Heat exchange
With retainer for removable article
Electrical component
C361S704000, C257S722000
Reexamination Certificate
active
06308771
ABSTRACT:
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to an apparatus and method of cooling a heat producing electronic component. More particularly, this invention relates to a novel configuration and design for a heat exchanger providing an apparatus and method for managing low velocity fluid flow. The invention thereby expands the envelope of cooling performance provided by fluid flow over plates.
2. Discussion of Related Art
It is important to dissipate the heat produced by electrical devices in order to extend the useful life of these devices. Heat dissipation is particularly important in the case of high-power electronic components, such as microprocessors and lasers, which generate a relatively high amount of heat in a relatively small area. Conventional heat sink devices typically utilize an array of extended surfaces, such as fins, integrally formed on a common base. The array of extended surfaces project into an ambient fluid surrounding the device. The base is placed in thermal intimate contact with a heat-producing device to provide a conduction path to the fin array. Through forced or natural convection, fluid circulation around the fin array acts as the heat transfer medium for cooling the device to an operable temperature.
Designing acceptable heat exchangers to adequately dissipate the heat generated by these heat generating components is a difficult task. These electronic components are typically used within systems housed in an enclosed cabinet having a fan mounted therein. The fan is mounted so as to pull cooling fluid across the heat generating electrical components. Given their relative simplicity, traditional extruded plate fin heat exchangers are generally preferred from both cost and implementation perspectives. Traditional plate fin heat exchangers generally offer high surface area relative to their size. However, the design of the conventional plate fin heat exchanger is often inadequate for dissipating heat generated from high power electronic components. Accordingly, conventional plate fin heat exchangers with novel design layouts for providing enhanced cooling of electronic components are a preferred apparatus for providing the proper cooling of the heat generating components.
Advances have been made involving the use of narrow channel and micro-channel plate fin heat exchangers for cooling electronic components. For example, U.S. Pat. No. 5,304,846 to Azar et al., discloses a narrow-channeled heat exchanger with certain geometric relations aimed at improving the heat dissipation of the heat exchanger. Specifically, the patent teaches optimal ratios relating the height of the plate fins to the width of the channels. The ratios may be selected for optimizing the heat dissipation capabilities of the heat exchanger for a given pressure drop across the heat exchanger.
Although narrow channel heat exchangers significantly improve heat dissipation, they, like all other plate fin designs, suffer from boundary layer formation. The boundary layer consists of hydrodynamic and thermal layers which result from friction or drag which occurs when the cooling fluid and the plate fins meet. This boundary layer of hot low velocity fluid blankets the plate fin heat exchanger insulating the exchanger from cooler fluid flow, which causes a reduction in heat transfer and premature egress of fluid from the fin field. In addition, the boundary layer narrows the remaining channel available for fluid flow and causes a reduction in the volume of the fluid flow, thereby significantly reducing the productivity of the heat exchanger. Accordingly, the conventional heat exchanger incorporating the narrow channel design continues to suffer from a lower productivity due to the formation of high pressure and a boundary layer.
The Assignee has a patent application Ser. No. 08/673,802, now U.S. Pat. No. 5,957,194, hereby incorporate by reference, disclosing a heat exchanger comprising a fin field for reducing formation of high pressure within the fin field, increasing efficient heat transfer, and preventing premature egress of fluid from the fin field. This particular heat exchange design comprise fluid control and fluid ventilation designs for achieving a reduction in high pressure fluid within the fin field. Although the modifications disclosed in Assignee's pending application successfully reduce the formation of high pressure and fluid by-pass, such modifications to the individual fins can be costly and difficult to manufacture. In the best mode of Applicant's invention herein, Applicant overcomes the formation of high pressure and fluid by-pass through a novel design. The novel fluid control and fluid ventilation elements of U.S. Pat. No. 5,957,194 may be incorporated into Applicant's invention to further increase the performance of the heat exchanger within the parameters of the present invention, Accordingly, the present invention comprises a narrow channel fan tail heat exchanger for alleviating the inefficiencies associated with prior art conventional heat exchanger.
Therefore, what is desirable is a plate fin heat exchanger that reduces and/or deters formation of high pressure, prevents the premature egress of fluid from the fin field caused by formation of high pressure, minimizes boundary layer formation without increasing pressure, and enhances heat transfer. The present invention incorporating a fan tail design together with a narrow channel configuration overcomes the outstanding issues present in the prior art and achieves the theoretical limit of cooling performance provided by fluid flow over a plate fin heat exchanger.
SUMMARY OF THE INVENTION
It is therefore the general object of the present invention to provide a novel and improved plate fin heat exchanger for dissipating heat from an electronic heat generating component.
It is a further object of the invention to provide a novel heat exchanger adapted for optimum performance with low velocity fluid flows for expanding the envelope of cooling performance from fluid flow over plate fins. The novel design comprises a thermally conductive plate in thermal communication with the heat generating component, an array of thermally conductive plate fins affixed to the base, wherein the plate fins define a fin field having channels. The fins of the heat exchanger are designed to be affixed to the base of the heat exchanger at an acute angle relative to the base, such that the angle of the fin to the base is less than or equal to ninety degrees and the effective width of the fin array exceeds the width of the base.
It is even a further object of the invention to provide a novel heat exchanger design wherein the fins are in thermal communication with the base and affixed thereto such that the effective width of the wing span of the fins exceeds the width of the base. Commonly referred to as a fan tail, such an enlarged wing span, when compared to conventional heat exchangers, provides an increased control volume thereby allowing a greater volume of fluid flow to enter the fin field.
In yet a further embodiment of the invention, the novel heat exchanger comprises a fin density of at least ten fins per inch or greater of base length thereby providing a narrow channel heat exchanger with a fan tail. The aspect ratio of the individual channels between the fins, as compared to parallel fins affixed perpendicular to the base through an extrusion method, generates a reduced pressure drop across the heat exchanger. Accordingly, the fluid flow entering the heat exchanger is increased.
It is even a further object of the invention to provide a novel heat exchanger comprising fins with surface modifications and communication means. An increased surface area of the heat exchanger is among the benefits associated with surface modifications, such as undulations. In addition, the communication means provides for a more effective cooling of the heat generating component by the fluid passing through the heat exchanger.
In accordance with the invention, these and other objective are achieved by providing
Advanced Thermal Solutions, Inc.
Flanigan Allen
Lieberman & Brandsdorfer LLC
LandOfFree
High performance fan tail heat exchanger does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with High performance fan tail heat exchanger, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and High performance fan tail heat exchanger will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2581191