Loop heat pipe and startup method for the same

Abstract

A loop heat pipe includes: a first evaporator and a second evaporator each of which vaporizes a liquid-phase working fluid and converts the liquid-phase working fluid to a vapor-phase working fluid; a first condenser and a second condenser each of which condenses the vapor-phase working fluid and converts the vapor-phase working fluid back to the liquid-phase working fluid; a first vapor line through which the working fluid converted to the vapor phase is transported to the first condenser; a first liquid line through which the working fluid converted to the liquid phase is transported to the second evaporator; a second vapor line through which the working fluid converted to the vapor phase is transported to the second condenser; and a second liquid line through which the working fluid converted to the liquid phase is transported to the first evaporator.

1 . A loop heat pipe comprising:
 a first evaporator and a second evaporator each of which vaporizes a liquid-phase working fluid by receiving heat from a heat source and thereby converts the liquid-phase working fluid to a vapor-phase working fluid;   a first condenser and a second condenser each of which condenses the vapor-phase working fluid by giving off heat and thereby converts the vapor-phase working fluid back to the liquid-phase working fluid;   a first vapor line through which the working fluid converted to the vapor phase by the first evaporator is transported to said first condenser;   a first liquid line through which the working fluid converted to the liquid phase by the first condenser is transported to said second evaporator;   a second vapor line through which the working fluid converted to the vapor phase by the second evaporator is transported to said second condenser; and   a second liquid line through which the working fluid converted to the liquid phase by the second condenser is transported to said first evaporator.   
     
     
         2 . The loop heat pipe as claimed in  claim 1 , further comprising a bypass line which connects between said first vapor line and said second vapor line. 
     
     
         3 . The loop heat pipe as claimed in  claim 2 , wherein said bypass line connects between a portion of said first vapor line in the vicinity of said first condenser and a portion of said second vapor line in the vicinity of said second condenser. 
     
     
         4 . The loop heat pipe as claimed in  claim 2 , wherein the cross-sectional area of a working fluid flow section of said bypass line is not larger than the cross-sectional area of a working fluid flow section of said first vapor line or said second vapor line. 
     
     
         5 . The loop heat pipe as claimed in  claim 4 , wherein the ratio of said cross-sectional area of said bypass line to said cross-sectional area of said first vapor line or said second vapor line is in the range of 0.1 to 1. 
     
     
         6 . The loop heat pipe as claimed in  claim 1 , wherein said first evaporator is located upwardly of said second evaporator as viewed along a plumbline direction. 
     
     
         7 . The loop heat pipe as claimed in  claim 1 , wherein said first condenser and said second condenser are constructed in integral fashion. 
     
     
         8 . The loop heat pipe as claimed in  claim 7 , wherein said first condenser includes a first condenser line and said second condenser includes a second condenser line, and wherein a plurality of heat sinking plates are coupled in common to both said first condenser line and said second condenser line. 
     
     
         9 . A method for starting up a loop heat pipe which comprises: a first evaporator and a second evaporator each of which vaporizes a liquid-phase working fluid by receiving heat from a heat source and thereby converts the liquid-phase working fluid to a vapor-phase working fluid; a first condenser and a second condenser each of which condenses the vapor-phase working fluid by giving off heat and thereby converts the vapor-phase working fluid back to the liquid-phase working fluid; a first vapor line through which the working fluid converted to the vapor phase by the first evaporator is transported to said first condenser; a first liquid line through which the working fluid converted to the liquid phase by the first condenser is transported to said second evaporator; a second vapor line through which the working fluid converted to the vapor phase by the second evaporator is transported to said second condenser; and a second liquid line through which the working fluid converted to the liquid phase by the second condenser is transported to said first evaporator, wherein said first evaporator is located upwardly of said second evaporator as viewed along a plumbline direction, and said first evaporator is started to receive heat after a predetermined length of time has elapsed from the time said second evaporator began to receive heat. 
     
     
         10 . The loop heat pipe startup method as claimed in  claim 9 , wherein said predetermined length of time is determined based on the time taken for the liquid-phase working fluid to begin to flow into said first evaporator. 
     
     
         11 . The loop heat pipe startup method as claimed in  claim 9 , wherein said loop heat pipe comprises a bypass line which connects between said first vapor line and said second vapor line.