Heat pipe having a wick with a hybrid profile

Abstract

A heat pipe system for conducting thermal energy. The heat pipe system includes a sealed tube having along its length a reservoir region, an evaporator region, and a condenser region, the tube having a first end and a second end and an inside wall. The system also includes a wick disposed adjacent the inside wall of the tube, the wick including a first portion at the first end of the tube and a second portion adjacent the first portion, wherein the first portion of the wick is thicker than the second portion of the wick, and wherein the second portion of the wick does not extend to the second end of the tube. The system also includes a working fluid contained within the tube.

What is claimed is: 
     
         1 . A heat pipe system for conducting thermal energy, comprising:
 a sealed tube having along its length a reservoir region, an evaporator region, and a condenser region, the tube having a first end, a second end, and an inside wall;   a wick disposed adjacent the inside wall of the tube, the wick comprising a first portion at the first end of the tube and a second portion adjacent the first portion, wherein the first portion of the wick is thicker than the second portion of the wick, and wherein the second portion of the wick does not extend to the second end of the tube; and   a working fluid contained within the tube.   
     
     
         2 . The heat pipe system of  claim 1 , further comprising a first heat source applied to the evaporator region. 
     
     
         3 . The heat pipe system of  claim 2 , further comprising a second heat source applied to the reservoir region. 
     
     
         4 . The heat pipe system of  claim 3 , wherein the first portion of the wick is in the reservoir region, the second portion of the wick is in the evaporator region, and the condenser region has no wick. 
     
     
         5 . The heat pipe system of  claim 4 , further comprising a heat sink in contact with the condenser region. 
     
     
         6 . The heat pipe system of  claim 5 , wherein the working fluid comprises water. 
     
     
         7 . A heat pipe system for conducting thermal energy, comprising:
 a sealed tube having along its length a reservoir region, an evaporator region, and a condenser region, the tube having a first end, a second end, and an inside wall extending between the first and second ends;   a wick disposed adjacent the inside wall of the tube, the wick comprising a first portion at the first end of the tube and a second portion adjacent the first portion and thinner than the first portion; and   a quantity of working fluid contained within the tube,   the heat pipe system having   a first state in which the wick holds substantially the entire quantity of working fluid, and   a second state in which heat is supplied to the evaporator region, in which the wick holds a portion of the quantity of working fluid, and in which a first part of a remainder of the working fluid has been heated to a vapor form, and in which a second part of the remainder of the working fluid is in condensed form on the inside wall of the tube in the condenser region of the tube.   
     
     
         8 . The heat pipe system of  claim 7 , further comprising a first heat source applied to the evaporator region. 
     
     
         9 . The heat pipe system of  claim 8 , further comprising a second heat source applied to the reservoir region. 
     
     
         10 . The heat pipe system of  claim 9 , wherein the first portion of the wick is in the reservoir region, the second portion of the wick is in the evaporator region, and the condenser region has no wick. 
     
     
         11 . The heat pipe system of  claim 10 , further comprising a heat sink in contact with the condenser region. 
     
     
         12 . The heat pipe system of  claim 11 , wherein the working fluid comprises water. 
     
     
         13 . A method of cooling using a heat pipe, the method comprising:
 heating a sealed tube at an evaporator region of the sealed tube located along the sealed tube between a condenser region and a reservoir region;   evaporating a working fluid in a first wick lining the evaporator portion of the sealed tube;   condensing the evaporated working fluid in the condenser region of the sealed tube;   moving the condensed working fluid back toward the evaporator portion of the sealed tube;   repeating the heating, evaporating, condensing, and moving steps with the condensed working fluid; and   maintaining a second wick lining the reservoir region of the sealed tube in a substantially dry condition during the heating, evaporating, condensing, and moving steps, wherein the second wick lining the reservoir region is thicker than the first wick lining the evaporator region.   
     
     
         14 . The method of  claim 13 , further comprising:
 condensing substantially all of the working fluid located within the sealed tube; and   retaining substantially all of the condensed working fluid within the first and second wicks after condensing substantially all of the working fluid located within the sealed tube.   
     
     
         15 . The method of  claim 13 , wherein evaporating a working fluid in a first wick lining the evaporator portion of the sealed tube comprises evaporating a working fluid in a first wick lining the evaporator portion of the sealed tube by applying a first heat source to the evaporator region. 
     
     
         16 . The method of  claim 13 , wherein maintaining a second wick lining the reservoir region of the sealed tube in a substantially dry condition comprises maintaining a second wick lining the reservoir region of the sealed tube in a substantially dry condition by applying a second heat source to the reservoir region. 
     
     
         17 . The method of  claim 13 , wherein condensing the evaporated working fluid in the condenser region of the sealed tube comprises condensing the evaporated working fluid in the condenser region of the sealed tube using a heat sink in contact with the condenser region. 
     
     
         18 . The method of  claim 13 , wherein the working fluid comprises water.