Thermal management system and computer arrangement

Abstract

It is the object of the present invention to provide a low weight, compact, low vertical profile thermal management system for removing heat from electronic components. The thermal management system comprises of a plurality of “flow-through” type cooling devices, a source of filtered pressurized fluid suitable for use as a coolant, and a fluid delivering device that supplies the cooling devices with fluid. A preferred fluid is air, such as a filtered pressurized air. The cooling device is comprised of a high conductivity metal matrix composite heat spreader, a miniature heat sink, preferably of the same material, a permeable heat exchanger with high specific surface, and a closure that provides structural integrity of the cooling device.

Description

RELATED APPLICATIONS [0001] This application claims the benefit of U.S. Provisional Application No. 60 / 591,254, filed on Jul. 26, 2004 and U.S. Provisional Application No. 60 / 560,382, filed on Apr. 7, 2004. The entire teachings of the above applications are incorporated herein by reference.FIELD OF INVENTION [0002] The present invention relates to a thermal management system, especially electronics cooling and computer arrangement, and more particularly, to high performance electronics thermal management device that achieves high heat dissipation rates and provides a compact arrangement in which the electronic components are disposed with maximized space and weight efficiency. BACKGROUND OF THE INVENTION [0003] High power electronic components continue to have an increasing demand for higher power dissipating waste heat generated during computer operating within a relatively confined space. A major thermal management challenge is to adjust the constantly increasing heat emission fro...

AI Technical Summary

Benefits of technology

[0018] It is the object of the present invention to provide a low weight, compact, low vertical profile thermal management system for removing heat from electronic components. The thermal management system comprises of a plurality of “flow-through” type cooling devices, a source of filtered pressurized fluid suitable for use as a coolant, and a fluid delivering device that supplies the cooling devices with fluid. A preferred fluid is air, such as a filtered pressurized air. The cooling device is comprised of a high conductivity metal matrix composite heat spreader, a miniature heat sink, preferably of the same material, a permeable heat exchanger with high specific surface, and a closure that provides structural integrity of the cooling device.

[0021] It is the further object of the present invention to provide a miniature air mover capable of overcoming the hydraulic resistance of the air filtration device and a plurality of the flow-through cooling devices.

[0023] It is the further object of the present invention to provide a high conductivity, CTE controlled heat spreader that is integrated metallurgically with a ceramic substrate, on which an electronic device can be placed using conventional technique. Thus, an ideal thermal contact between the ceramic substrate and a heat removal structure is created, and use of the low thermal conductivity interface materials is avoided.

[0026] It is the further object of the present invention to provide a computer arrangement in which one or more electronic components can be arranged in any desirable order and orientation without concern of air flow directivity, components proximity, gravitation, and electro magnetic influence. New computer arrangement comprises the encapsulated modules with electronic components and the thermal management system on the basis the flow-through cooling devices and a supply of filtered pressurized air. New computer arrangement provides freedom in layout for electronic devices and protection from exterior contamination factors.

[0028] It is the further object of the present invention to provide a method for manufacturing the components of “flow-through” cooling devices in high volume and low cost.

Problems solved by technology

A major thermal management challenge is to adjust the constantly increasing heat emission from the electronic components to the constantly reducing weight and size of the computer arrangement.

Functional and designing division onto the heat removal and heat dissipating parts becomes typical for the modern computer architecture because the currently used cooling material and technologies can no longer manage the increased heat flux being coupled in one thermal management device.

Unfortunately, the currently used solutions are not free from the drawbacks.

The solid-state conductivity heat removal devices are heavy and their thermal conductivity often is beyond of what is required.

Another disadvantage of the commonly used aluminum and cooper heat spreaders is the CTE mismatch with CTEs of semiconductor materials by the factor 2-3.

The liquid cooling close-loop systems are heavy, roomy, and expensive in manufacturing.

Heat pipes are often bulky and fragile.

Thermoelectric cooling devices are heavy and bulky; their energy consumption is in a range that puts them outside of battery-driven applications.

Distribution of air streams within the finned structure is uneven due to turbulent nature of air flow and formation of the flow stagnation areas.

Conventional heat sink-fan tandems produce a large amount of high velocity air flow that is the main source of computer noise.

A large amount of air pumped through the computer causes deposition of contaminations on the surface of electronic components that reduces heat exchange additionally.

Use of air filtration devices for fan air movers is limited because of the air pressure developed by air fans do not meet the pressure drop conditions in the air filtration systems.

A large volume air flows produced by fans are used in inefficient way in computer systems.

Unfortunately, the prior art does not disclose solutions able to meet these requirements.

Still another disadvantage of the common design heat sinks is that they occupy too much physical volume to be practical in extremely confined applications.

However, the mentioned metal matrix composite materials do not provide exact harmony with the CTE of such semiconductor materials as silicon or gallium arsenide.

Besides, the conventionally used sintering and die casting manufacturing technologies do not provide production of the net-shape, net-size components with fine details.

Additional machining is requires for theses difficult-to-machine materials that adds to their cost.

Further, individual components, such as a microprocessor, may produce significant heat emission in very local areas.

As computer systems have become more complex and powerful, the individual components generate more heat.

Unfortunately, as the number of fins has increased, airflow provided by the fans has been inadequate to penetrate the now relatively dense fin structure, limiting the ability to cool the component.

Increasing air flow to a sufficiently high level has proven problematic because fans tend to be noisy, consume substantial electrical power and increase their size consuming valuable real estate in the computer housing.

These auxiliary fans have provided some relief but they have created additional problems.

For example, increase of the number of auxiliary fans adds to the cost and complicity of the computer system.

Further, with the growing complexity of modern computer systems, more and more individual components require additional cooling capacity.

As the number of components grows, the problem associated with installing additional auxiliary fans is compounded.

This creates an additional problem of air flows matching, which often becomes an obstacle for further miniaturization of computer systems.

The fans take up valuable space within the housing, increase costs and noise, and are particularly susceptible to failure due to their mechanical nature.

The fans and heat sinks also complicate the general layout of the components within the housing, hampering overall size of the computer.

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