Nanostructured micro heat pipes

Abstract

A heat pipe comprising a chamber; a wick in the chamber, and a heat sink, which is adjacent to a first portion of the wick. A heat source adjacent to a second portion of the wick, wherein the wick is configured such that a gas condenses at the first portion of the wick and a liquid evaporates at the second portion of the wick. The fluid moves from the first portion of the wick to the second portion of the wick, and wherein the wick comprises nanostructures having a differentially-spaced apart gradient along the length of the wick so as to promote capillary fluid flow therealong.

1 . A heat pipe, comprising:
 a chamber;   a wick in the chamber,   a heat sink adjacent to a first portion of the wick; and   a heat source adjacent to a second portion of the wick, wherein the wick is configured such that a gas condenses at the first portion of the wick and a liquid evaporates at the second portion of the wick, wherein fluid moves from the first portion of the wick to the second portion of the wick, and wherein the wick comprises nanostructures having a differentially-spaced apart gradient along the length of the wick so as to promote capillary fluid flow therealong.   
     
     
         2 . The heat pipe of  claim 1 , further comprising:
 a substance in the chamber, the substance changing from gas phase to liquid phase at the first portion of the wick and from liquid phase to gas phase at the second portion of the wick.   
     
     
         3 . The heat pipe of  claim 1 , wherein the nanostructures comprise:
 an array of nanowires, nanopores, nanotubes, or any nanoscale protrusions.   
     
     
         4 . The heat pipe of  claim 1 , wherein the nanostructures are formed by one or a combination of the following processes:
 directly depositing a nanoporous film on a substrate;   depositing a solid film on a substrate and then electrochemically etching the solid film forming arrays of nano-pores;   electrochemically growing nanowires or nanotubes in the nano-pores;   annealing the nanowires to form polycrystalline wires;   etching the film away leaving a nanowire array; and/or   direct deposition of nanowires on a substrate.   
     
     
         5 . The heat pipe of  claim 4 , wherein the nanostructure size and density are determined by the manufacturing process. 
     
     
         6 . The heat pipe of  claim 1 , wherein the nanostructures are spaced between 20 nm to 500 nm apart from one another. 
     
     
         7 . The heat pump of  claim 1 , wherein the nanostructures are spaced farther apart at the first portion of the wick and closer together at the second portion of the wick. 
     
     
         8 . A heat dissipation system, comprising:
 a chamber;   a heat sink;   a heat source; and   a nanostructure array extending from the heat source.   
     
     
         9 . The heat dissipation system of  claim 8 , further comprising:
 a plurality of channels in the heat sink.   
     
     
         10 . The heat pipe of  claim 1 , wherein the wick has a capillary pressure between 0.01 MPa to 100 MPa. 
     
     
         11 . A nanostructured composite wick comprising:
 a channel; and   a plurality of nanostructures, wherein the nanostructures have a differentially-spaced apart gradient along the length of the channel so as to promote capillary fluid flow therealong.   
     
     
         12 . The wick of  claim 11 , wherein the nanostructure size and density are determined by the manufacturing process. 
     
     
         13 . The wick of  claim 11 , wherein the nanostructures are spaced between 20 nm to 500 nm apart from one another. 
     
     
         14 . The wick of  claim 11 , further comprising a heat source adjacent to a second portion of the wick, wherein the wick is configured such that a gas condenses at the first portion of the wick and a liquid evaporates at the second portion of the wick, wherein fluid moves from the first portion of the wick to the second portion of the wick, and wherein the nanostructures are spaced farther apart at a first portion of the wick and closer together at a second portion of the wick. 
     
     
         15 . The heat pipe of  claim 14 , further comprising:
 a substance in the chamber, the substance changing from gas phase to liquid phase at the first portion of the wick and from liquid phase to gas phase at the second portion of the wick.   
     
     
         16 . The heat pipe of  claim 11 , wherein the nanostructures comprise:
 an array of nanowires, nanopores, nanotubes, or any nanoscale protrusions.