Thermal Impedance Matching Using Common Materials

Abstract

A device and method for dissipating heat from a source of heat is described. A plurality of layers of thermally conductive materials receives a flow of heat from a source of heat. A first layer of the plurality of layers receives the flow of heat from the source of heat and redirects and transfers the flow of heat to a second of the plurality of layers. Each layer has a separate preselected thermal impedance to control a desired temperature change across the plurality of layers and to maintain a desired operating temperature of the source heat.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS[0001]This Application is a continuation-in-part application of co-pending U.S. application Ser. No. 13 / 375,060 filed on Nov. 29, 2011 which is a national stage filing under 35 U.S.C. §371 of PCT / US2011 / 022534 which has an international filing date of Jan. 26, 2011 and which was published as WO 2011 / 094282 A1 on Aug. 4, 2011 and which claimed the benefit of U.S. Provisional Patent Application No. 61 / 298,406 filed Jan. 26, 2010. The contents of all three applications are incorporated herein by reference as if fully set forth herein.FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT[0002]N / ATECHNICAL FIELD[0003]The invention relates to heat management systems. More particularly, the invention relates to heat management systems wherein a heat flow is vectored to enhance rapid dissipation into regions less thermally conductive than the source element. Although applicable anywhere heat flow is critical, an immediate and important application is in lighting...

AI Technical Summary

Benefits of technology

[0016]Another aspect of the invention is directed to a method of dissipating heat from a source of heat. The method comprises the steps of: (1) providing a source of heat; (2) providing a first layer of a first material having a first thermal conductivity adjacent the source of heat; (3) providing a second layer of a second material having a second thermal conductivity adjacent the first layer; and (4) selecting volumetric dimensions of the first and second layers to match a thermal impedance of the first layer to a thermal impedance of the second layer and to minimize a change in temperature from the first layer to the second layer.

Problems solved by technology

When natural convection is not adequate, a power device typically a blower 6, is used to provide a higher level of mass flow and to gain the desired thermal equilibrium, thus consuming additional energy, increasing the size of the system and adds weight / material / cost.

A disparity of thermal impedances makes this process highly ineffective but nearly universally accepted as an adequate and reasonable approach in the art.

Radiation typically does not come into play in most applications involving living spaces, as these applications require higher temperatures than can be tolerated safely by its human inhabitants.

The temperature at which reflex action can safely protect someone from injury of burns is about 80° C. The temperature at which radiation is effective is in the order of hundreds of degrees C. Therefore, the use of radiation cooling is not a method compatible with most spaces occupied by people.

A widespread use of light emitting diodes (LED) in industrial lighting is limited by the LEDs sensitivity to temperature.

These methods are expensive and severely limit the design of aesthetically pleasing and practical lighting fixtures.

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