Compound heat pipe, method of manufacturing the same, heat exchanger and heat exchanger system using the same

Abstract

The compound heat pipe according to the present invention may overcome physical limits, which a single metal pipe might have, by integrally joining different metal pipes having different physical properties, forming ridges on an inner surface thereof the pipe and protrusions on an outer surface thereof and may first increase heat transfer capability by increasing the heat transfer area between the pipe and fluid. Further, the compound heat pipe according to the present invention may secondly increase the heat transfer capability by setting the noncontact rate to be 30% or less so that the heat transfer rate of the compound heat pipe in the radial direction may be optimized.

1 . A compound heat pipe comprising:
 a first pipe body having at least one or more protrusions on an outer surface of the first pipe body, wherein the first pipe body is formed of a first metal material;   a second pipe body coupled with the first pipe body inside the first pipe body, wherein the second pipe body is formed of a second metal material having a different physical property from a physical property of the first metal material, and the second pipe has at least one or more ridges formed on an inner surface of the second pipe; and   an interface where the first and second pipe bodies abut each other, wherein a noncontact rate due to a gap present at the interface as defined in Equation 1 satisfies 30% or less:   
       
         
           
             
               
                 
                   
                     
                       Noncontact 
                        
                       
                           
                       
                        
                       rate 
                        
                       
                           
                       
                        
                       
                         ( 
                         % 
                         ) 
                       
                     
                     = 
                     
                       
                         L 
                         
                           2 
                            
                           π 
                            
                           
                               
                           
                            
                           
                             r 
                             ′ 
                           
                         
                       
                       × 
                       100 
                     
                   
                 
                 
                   
                     [ 
                     
                       Equation 
                        
                       
                           
                       
                        
                       1 
                     
                     ] 
                   
                 
               
             
           
         
         where L refers to a sum of lengths of circumferences of gaps present at the interface, and r′ refers to a radius of the interface. 
       
     
     
         2 . The compound heat pipe of  claim 1 , wherein the noncontact rate satisfies 5.0% to 25.3%. 
     
     
         3 . The compound heat pipe of  claim 1 , wherein the first pipe body has a Young's modulus of 60 to 130 GPa and the second pipe body has a Young's modulus of 100 to 200 GPa. 
     
     
         4 . The compound heat pipe of  claim 1 , wherein the first metal material is Al or an alloy of Al. 
     
     
         5 . The compound heat pipe of  claim 4 , wherein the first pipe body has a Young's modulus of 60 to 130 GPa. 
     
     
         6 . The compound heat pipe of  claim 4 , wherein the second metal material is any one of Cu, an alloy of Cu, Ti, an alloy of Ti, SUS, and an alloy of SUS. 
     
     
         7 . The compound heat pipe of  claim 6 , wherein the second pipe body has a Young's modulus of 100 to 200 GPa. 
     
     
         8 . The compound heat pipe of  claim 1 , wherein the first metal material is Cu or an alloy of Cu. 
     
     
         9 . The compound heat pipe of  claim 8 , wherein the first pipe body has a Young's modulus of 60 to 130 GPa. 
     
     
         10 . The compound heat pipe of  claim 8 , wherein the second metal material is any one of Ti, an alloy of Ti, SUS, and an alloy of SUS. 
     
     
         11 . The compound heat pipe of  claim 10 , wherein the second pipe body has a Young's modulus of 100 to 200 GPa. 
     
     
         12 . The compound heat pipe of  claim 1 , wherein the first metal material is any one of Al, Cu, and an alloy of Al and Cu, and the second metal material is any one of Cu, Ti, SUS, and an alloy of Cu, Ti, and SUS, and wherein the first pipe body has a Young's modulus of 60 to 130 GPa, and the second pipe body has a Young's modulus of 100 to 200 GPa. 
     
     
         13 . A heat exchanger comprising the compound heat pipe of  claim 1 . 
     
     
         14 . A heat exchanger system comprising the heat exchanger of claim  13 , wherein the heat exchanger system performs heat exchange. 
     
     
         15 . A method of manufacturing a compound heat pipe comprising:
 producing a bare tube by inserting a second metal pipe for a second pipe body into a first metal pipe for a first pipe body and then performing an expanding process; and   pulling the bare tube while rotating the bare tube with a helix type core inserted into the bare tube for forming ridges and a roller positioned outside the bare tube for forming protrusions, wherein a pressing force when performing the expanding process and a pressure when forming the ridges and protrusions are adjusted so that a noncontact rate defined in Equation 1 is not more than 30% due to a gap present at an interface where the first and second pipe bodies abut each other:   
       
         
           
             
               
                 
                   
                     
                       Noncontact 
                        
                       
                           
                       
                        
                       rate 
                        
                       
                           
                       
                        
                       
                         ( 
                         % 
                         ) 
                       
                     
                     = 
                     
                       
                         L 
                         
                           2 
                            
                           π 
                            
                           
                               
                           
                            
                           
                             r 
                             ′ 
                           
                         
                       
                       × 
                       100 
                     
                   
                 
                 
                   
                     [ 
                     
                       Equation 
                        
                       
                           
                       
                        
                       1 
                     
                     ] 
                   
                 
               
             
           
         
         where L refers to a sum of lengths of circumferences of gaps present at the interface, and r′ refers to a radius of the interface.