Coiled heat pipes and methods thereof

Abstract

A coiled heat pipe and methods of making a coiled heat pipe are provided. The coiled heat pipe includes a sealed-exterior coil and a plurality of interior-perforated coils. The exterior coil and the plurality of interior-perforated coils are be formed from a single aluminum sheet. The exterior coil is sealed and houses, or otherwise contains, a partial vacuum and a working fluid.

1 ) A coiled heat pipe comprising: an exterior coil and a plurality of interior-perforated coils, wherein the exterior coil and the plurality of interior-perforated coils are formed from a single aluminum sheet. 
     
     
         2 ) The coiled heat pipe of  claim 1 , wherein the aluminum sheet is a 5xxx series aluminum. 
     
     
         3 ) The coiled heat pipe of  claim 1 , wherein the exterior coil is sealed and contains: a partial vacuum and a working fluid. 
     
     
         4 ) The coiled heat pipe of  claim 3 , wherein the working fluid is selected from the group consisting of water, ethanol, acetone; butane, pentanone, sodium, mercury, other organic compounds, and combinations thereof. 
     
     
         5 ) The coiled heat pipe of  claim 1 , wherein the plurality of interior-perforated coils includes at least two interior-perforated coils. 
     
     
         6 ) The coiled heat pipe of  claim 1 , wherein a first end of the single aluminum sheet forms the plurality of interior-perforated coils and the first end is contained within the exterior coil, and a second end of the single aluminum sheet is sealed to a portion of the exterior coil. 
     
     
         7 ) The coiled heat pipe of  claim 1 , wherein the plurality of interior-perforated coils each include a first and second surface, and the plurality of interior-perforated coils are spaced apart such that the first and second surfaces may both function as wicking surfaces. 
     
     
         8 ) The coiled heat pipe of  claim 1 , wherein the interior-perforated coils further comprise spacers selected from the group comprising: bumps, tabs, deliberate burrs, and the like. 
     
     
         9 ) The coiled heat pipe of  claim 1 , further comprising a lap extending from the exterior coil. 
     
     
         10 ) A method of producing a coiled heat pipe comprising:
 providing an aluminum alloy sheet;   optionally heat treating the aluminum alloy sheet;   perforating a first portion of the aluminum alloy sheet to form a perforated end;   coiling the perforated end about itself to form a plurality of interior-perforated coils, having interior-perforated coil outer perimeters;   coiling a non-perforated end of the aluminum alloy sheet about the plurality of interior-perforated coils to form a lap, and an exterior coil having a distal end and exterior coil outer perimeters; and   optionally etching the aluminum alloy sheet with a solvent.   
     
     
         11 ) The method of  claim 10 , wherein the heat treating produces a continuous etchable phase on the aluminum alloy sheet, and wherein the solvent dissolves the continuous etchable phase on the aluminum alloy sheet. 
     
     
         12 ) The method of  claim 11 , further comprising: thermomechanically processing the aluminum alloy sheet to produce grains having a size and a shape suitable for wicking, wherein the heat treating produces a continuous etchable phase on the grain boundaries, and wherein the solvent dissolves the continuous etchable phase on the grain boundaries. 
     
     
         13 ) The method of  claim 10 , further comprising: sealing the distal end of the exterior coil to a portion of the exterior coil; sealing interior-perforated coil perimeters and the exterior coil perimeters to form a sealed-exterior coil. 
     
     
         14 ) The method of  claim 13 , further comprising: removing at least a portion of the gas within the coiled heat pipe; and filling at least a portion of coiled heat pipe with a working fluid, wherein the working fluid is selected from the group consisting of water, ethanol, acetone, sodium, mercury, and combinations thereof. 
     
     
         15 ) The method of  claim 13 , wherein the free edge of the exterior coil is sealed to a portion of the exterior coil by a method selected from group consisting of welding and adhesive bonding. 
     
     
         16 ) The method of  claim 13 , further comprising: removing the lap. 
     
     
         17 ) The method of  claim 10 , wherein the continuous etchable phase is magnesium bearing, and the solvent is nitric acid. 
     
     
         18 ) The method of  claim 18 , wherein the etching step is from about 5 minutes to about 90 minutes at a temperature range of about 30° C. to about 90° C. 
     
     
         19 ) The method of  claim 12 , wherein the grain size ranges from about 10 microns to about 500 microns. 
     
     
         20 ) The method of  claim 12 , further comprising the step of straining the continuous etchable phase on the grain boundaries, by rolling, to deform the grain boundaries in the direction of the strain before the etching step.