The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Aug. 22, 1989
Filed:
Jun. 02, 1988
Michael M Ladd, Renton, WA (US);
The Boeing Company, Seattle, WA (US);
Abstract
A heat exchanger having a variable thermal conductance is disclosed. The thermal conductance varies according to the absolute and relative temperatures between a high-temperature wall and a low-temperature wall. The heat exchanger includes an interior volume having a heat transfer medium therein. Fins extend from the low-temperature wall of the heat exchanger into the interior volume. The heat transfer medium in the fluid phase circulates over the fin surface area to transfer heat by convection and conduction from the high-temperature wall to the low-temperature wall. In the event the temperature of the heat transfer medium decreases, such as by a drop in the temperature of the low-temperature wall or by a decrease in heat flowing through the heat exchanger, a portion of the heat transfer fluid solidifies or freezes, which reduces the effective fin surface area and the circulation area. This reduces the thermal conductance of the heat exchanger. The heat transfer medium is selected based on the requirements of the heat transfer system. The fin configruation, the number of fins, their respective surface areas, and the distance of the fin tip to the high-temperature wall are also selected based on the system heat transfer requirements.