Micro-channel pulsating heat pipe
A heat pipe device and a corresponding method in which micro-channel embedded pulsating heat pipes are incorporated into a substrate. A volume of fluid in a vacuum is introduced into a micro-channel which will become slugs of liquid. Heating of the contents of the micro-channel at an evaporator region (heat source) will cause vaporization within the micro-channel and cooling at a heat sink will cause condensation within the micro-channel, acting to both drive fluid flow within the micro-channel and efficiently transfer heat. Such devices could be used in a number of different configurations, including one as a stacked set of micro-channel embedded substrates.
1. A micro-channel embedded heat pipe comprising:
a first sheet having a first serpentine trace pattern;
a second sheet bonded onto said first sheet, said second sheet having a second serpentine trace pattern substantially matching said first serpentine trace pattern such that when said first sheet and said second sheet are bonded together to form a bonded sheet, a wire-free serpentine micro-channel is formed in said bonded sheet; and
at least one fill tube on at least one edge of the bonded sheet, allowing introduction of a fluid into said wire-free serpentine micro-channel;
wherein said wire-free serpentine micro-channel has a first end region having an evaporator region and has an opposed second end region having a condenser region.
2. The micro-channel embedded heat pipe of claim 1 , further including:
a liquid, contained within said wire-free serpentine micro-channel and partially filling said wire-free serpentine micro-channel; and
said wire-free serpentine micro-channel having a portion that is evacuated to at least a partial vacuum.
3. The micro-channel embedded heat pipe of claim 1 , wherein said wire-free serpentine micro-channel has said evaporator region and said condenser region each including a respective plurality of bends of said wire-free serpentine micro-channel.
4. The micro-channel embedded heat pipe of claim 1 , further comprising a working fluid introduced into said wire-free serpentine micro-channel, wherein said wire-free serpentine micro-channel spanning between said condenser region and said evaporator region is sealed after partially filling said wire-free serpentine micro-channel with said working fluid wherein no active fluid driver is in fluid communication with said working fluid.
5. A micro-channel embedded heat pipe comprising:
a planar substrate;
a wire-free serpentine micro-channel embedded within said planar substrate;
a working fluid that partially fills said wire-free serpentine micro-channel;
at least one evaporation region, on said planar substrate, the at least one evaporation region including a plurality of bends of said wire-free serpentine micro-channel; and
at least one condensation region on said planar substrate.
6. The micro-channel embedded heat pipe of claim 5 , further comprising:
a plurality of stacked planar substrates, including said planar substrate, each of said planar substrates having a respective serpentine micro-channel embedded therewithin;
said at least one evaporation region being included on said plurality of stacked planar substrates; and
said at least one condensation region being included on said plurality of stacked planar substrates.
7. The micro-channel embedded heat pump of claim 5 , wherein at least one evaporation transfer region includes a plurality of evaporation thermal transfer regions.
8. The micro-channel embedded heat pump of claim 5 , wherein at least one condensation transfer region includes a plurality of condensation thermal transfer regions.
9. The micro-channel embedded heat pump of claim 5 , wherein said planar substrate is incorporated into a structural element.
10. The micro-channel embedded heat pump of claim 5 , wherein the serpentine channels may vary in diameter size allowing the regulation of flow.
11. The micro-channel embedded heat pipe of claim 5 , further comprising a fill tube, wherein:
said wire-free serpentine micro-channel embedded within said planar substrate has said working fluid introduced by said fill tube positioned to allow said working fluid to be introduced into said wire-free serpentine micro-channel to partially fill said wire-free serpentine micro-channel; and
an unfilled region of said wire-free serpentine micro-channel is evacuated to a vacuum.
12. The micro-channel embedded heat pump of claim 5 , wherein said planar substrate includes two metallurgically joined sheets of material.
13. The micro-channel embedded heat pump of claim 5 , wherein said micro-channel includes a first plurality of micro-channel sections having a relatively larger cross-sectional area, and a second plurality of micro-channel sections having relatively small cross-sectional areas.