The present invention relates to conduction-cooled electronics modules, and more particularly a means to adapt existing conduction-cooled electronics modules into a convection-cooled chassis.
Electronics modules are incorporated into modern systems for a variety of functions, ranging from basic communications and navigation in commercial aircraft to complex Airborne Early Warning (AEW) systems in military aircraft or battlefield management systems in ground vehicles. A primary high end electronics module standard used in the industry is the 6U Versa Module Eurocard (VME).
Existing high reliability, conduction cooled, 6U VME electronics modules for use in high performance avionics systems such as those in the F-18 or F-15 aircraft are maintained at operational temperatures by thermal conduction to cold walls. However, many ground vehicles and aircraft platforms, such as helicopters, do not have refrigerated cooling systems and rely on low pressure ambient air for temperature moderation.
As a result, a means to utilize conduction-cooled electronics modules in an air cooled system is desired.
According to one embodiment of the present invention, there is provided a modified convection-cooled VME compatible chassis that includes a convection bridge thermally interfaced with a VME electronics module just as a conduction chassis would. No modification to the VME electronics module is required, since the convection bridge is clamped or otherwise placed between the VME electronics module and the modified chassis. To enhance heat dissipation, an alternative embodiment of the present invention comprises fins (oriented in a direction other than horizontally) on the convection bridge. For better heat transfer, another alternative embodiment of the present invention comprises interstitial material such as grease or indium foil between the convection bridge and the VME electronics module. To improve convection properties, another alternative embodiment of the present invention comprises compatible air-moving appliances, such as a fan, as part of the modified VME chassis.
The present invention provides a means for adapting conduction-cooled electronics modules into a convection-cooled chassis, wherein a conduction-cooled module is modified by mounting a finned cooling plate or “convection bridge” to the heat dissipative surfaces of the module. The fins of the convection bridge create a large surface area and a low resistance air path through the avionics chassis. Thus, the finned convection bridge permits increased air flow through the avionics chassis, cooling the conduction-cooled electronics module by convection cooling. The concept utilizes additional card slots in the chassis to achieve the surface area necessary to provide adequate cooling with low pressure ambient air.
The fins on the finned-convection-bridge heat exchanger 104 are stationary fins; that is, they are not designed to move once the finned-convection-bridge heat exchanger 104 is manufactured. However, the fins on the finned-convection-bridge heat exchanger 104 may be mounted in the same orientation or in different orientations. For example, the fins on the finned-convection-bridge heat exchanger 104 may be mounted such that they are in the same direction, such as shown in the finned-convection-bridge heat exchanger 104.
The finned-convection-bridge heat exchanger 104 depicted in
As such, adaptation of the standard 6U VME electronics module 102 using a finned-convection-bridge heat exchanger 104 allows the use of the standard 6U VME electronics module 102 in a convection-cooled chassis by having the convection finned-convection-bridge heat exchanger 104 act as the thermal conducting interface just as a conduction chassis would otherwise interface with the standard conduction-cooled 6U VME electronics module 102. Further, the enhanced 6U VME electronics module 100 as described may mechanically secured in a convection-cooled chassis by wedgelocks in the same manner that a standard 6U VME conduction-cooled electronics module 102 is mechanically secured in a conduction-cooled chassis.
The cooling performance of this adaptation can be further enhanced by use of an interstitial material such as grease or indium foil between the standard 6U VME conduction-cooled electronics module 102 and the finned-convection-bridge heat exchanger 104.
As shown, the enhanced 6U VME module 302 uses a wider chassis slot interface and takes up the space of two modules when compared to the standard 6U VME conduction-cooled electronics module 308. As discussed before, the enhanced 6U VME electronics module 302 comprises a standard 6U VME conduction cooled electronics module coupled with a convection bridge heat exchanger, such as finned-convection-bridge heat exchanger 104 described with respect to
The purpose of the modified chassis side panel 414 is to provide air inlets so that air can be drawn through in the case of the chassis comprising a fan or any air-moving appliance. The air inlets can take different forms, from large air vents to small air holes. The chassis may need an increased slot width for this configuration, but as long as the card slot pitch height 410 is a multiple of 0.8 inches, compatibility with generic VME backplanes is maintained. Adaptations of electronics modules into convection-cooled chassis will typically entail pairing of the finned-convection-bridge heat exchanger with the existing product and replacement of the existing chassis side panels with modified chassis panels 414.
One embodiment of the present invention provides a means to utilize standard 6U VME conduction-cooled electronics modules designed for high end aircraft in other system applications without refrigerated cooling systems, saving money and time by eliminating the need to redesign modules for ambient air cooled applications. Alternate embodiments of the present invention may include the convection bridge heat exchanger being permanently mounted to the chassis, allowing direct insertion of standard 6U VME conduction-cooled electronics modules into the chassis. One of ordinary art in the skill should find that similar adaptations of the present invention can be implemented for other standard VME dimensions such as 3U or 9U modules.
The present application claims priority to U.S. Provisional Patent Application No. 61/008,191 filed on Dec. 11, 2007 entitled “Means to Utilize Conduction Cooled 6U VME Electronics Modules in an Air Cooled Avionics System”, the entire contents of which are incorporated herein for all purposes.
| Number | Date | Country | |
|---|---|---|---|
| 61008191 | Dec 2007 | US |