Apparatus for reducing evaporator resistance in a heat pipe

Abstract

An arrangement is provided for cooling a heat-generating device (e.g., an integrated circuit chip) in a system such as a laptop computer. The arrangement includes a heat pipe having an evaporator made of porous materials with substantially uniformly sized pores and a wick made of finely porous material. The evaporator is thinner, on average, than the wick.

1 . A cooling apparatus, comprising: 
 a heat pipe to transfer heat from a first section to a second section, the heat pipe having an evaporator made of substantially uniform pore sized material; and    a heat exchanger, coupled to the heat pipe, to dissipate heat from the second section of the heat pipe.    
   
   
       2 . The cooling apparatus of  claim 1 , wherein the first section comprises an evaporator section in the heat pipe, and the second section comprises a condenser section in the heat pipe.  
   
   
       3 . The cooling apparatus of  claim 1 , wherein the heat pipe comprises: 
 a liquid coolant;    an evaporator, when heated, to evaporate at least a portion of the liquid coolant, the evaporator having a thin porous structure made of substantially uniform pore sized material; and    a wick to bring the at least a portion of the liquid coolant to the evaporator.    
   
   
       4 . The cooling apparatus of  claim 3 , wherein the heat pipe further comprises a container to enclose the evaporator, the wick, and the liquid coolant.  
   
   
       5 . The cooling apparatus of  claim 3 , wherein the evaporator comprises at one to two layers of porous material with the thickness of a layer being approximately the average diameter of particles that make the layer.  
   
   
       6 . The cooling apparatus of  claim 5 , wherein the particles in the evaporator comprises approximately substantially uniformly sized particles with an average diameter in an approximate range from 25 μm to 150 μm.  
   
   
       7 . The cooling apparatus of  claim 3 , wherein the wick comprises a porous structure made of finely porous material with average thickness in an approximate range from 0.5 mm to 1 mm.  
   
   
       8 . The cooling apparatus of  claim 3 , wherein the porous structure of the evaporator comprises particles whose average diameter is larger than the average diameter of particles in the porous material in the wick.  
   
   
       9 . The cooling apparatus of  claim 3 , wherein the average thickness of the porous structure of the evaporator is thinner than the average thickness of the porous structure of the wick.  
   
   
       10 . A heat pipe, comprising: 
 a liquid coolant;    an evaporator, when heated, to evaporate at least a portion of the liquid coolant, the evaporator having a porous structure made of substantially uniform pore sized material; and    a wick to bring the at least a portion of the liquid coolant to the evaporator.    
   
   
       11 . The heat pipe of  claim 10 , further comprising a container to enclose the evaporator, the wick, and the liquid coolant.  
   
   
       12 . The heat pipe of  claim 10 , wherein the evaporator comprises one to two layers of porous material with the thickness of a layer being approximately an average diameter of particles that make the layer.  
   
   
       13 . The heat pipe of  claim 12 , wherein the particles in the evaporator comprises approximately uniformly sized particles with an average diameter in an approximate range from 25 μm to 150 μm.  
   
   
       14 . The heat pipe of  claim 10 , wherein the wick comprises a porous structure made of finely porous material with average thickness in an approximate range from 0.5 mm to 1 mm.  
   
   
       15 . The heat pipe of  claim 10 , wherein the porous structure of the evaporator comprises particles whose average diameter is larger than the average diameter of particles in the porous material in the wick.  
   
   
       16 . The heat pipe of  claim 10 , wherein average thickness of the porous structure of the evaporator is thinner than the average thickness of the porous structure of the wick.  
   
   
       17 . A system, comprising: 
 a heat-generating device; and    a cooling system to dissipate heat generated by the heat-generating device using a heat pipe, the heat pipe having an evaporator made of substantially uniform pore sized material.    
   
   
       18 . The system of  claim 17 , wherein the heat-generating device comprises an integrated circuit chip.  
   
   
       19 . The system of  claim 17 , wherein the cooling system comprises: 
 a heat pipe, including an evaporator section and a condenser section, to transfer heat from the evaporator section to a condenser section, the heat pipe having an evaporator made of substantially uniform pore sized material; and    a heat exchanger, coupled to the heat pipe, to dissipate heat from the condenser section.    
   
   
       20 . The system of  claim 19 , wherein the heat pipe comprises: 
 a liquid coolant;    an evaporator, when heated, to evaporate at least a portion of the liquid coolant, the evaporator having a porous structure made of substantially uniform pore sized material;    a wick to bring the at least a portion of the liquid coolant to the evaporator, the thickness of the wick being greater on average than the thickness of the evaporator; and    a container to enclose the evaporator, the wick, and the liquid coolant.    
   
   
       21 . The system of  claim 20 , wherein the evaporator comprises one to two layers of porous material with the thickness of a layer being approximately the average diameter of particles that make the layer, the average diameter of particles being in an approximate range from 25 μm to 150 μm.  
   
   
       22 . The system of  claim 20 , wherein the wick comprises a porous structure made of finely porous material with average thickness in an approximate range from 0.5 mm to 1 mm.  
   
   
       23 . The system of  claim 20 , wherein the porous structure of the evaporator comprises particles whose average diameter is larger than average diameter of particles in porous material that makes the wick.  
   
   
       24 . The system of  claim 19 , wherein the heat exchanger extracts heat from vapor in the condenser section to condense the vapor to liquid.  
   
   
       25 . The system of  claim 24 , wherein the heat exchanger comprises a fan to enhance air flow and a plurality of fins to dissipate heat extracted from the vapor to ambient air.