Loop type heat pipe and waste heat recovery device

Abstract

A loop type heat pipe includes an evaporator located to evaporate a refrigerant by heat-exchanging with a first fluid as a heat source, and a condenser located to liquefy and condense the evaporated vapor refrigerant by heat-exchanging with a second fluid to be heated. The condenser has a refrigerant condensation side on which the condensed liquid refrigerant flows, and a refrigerant un-condensation side on which the vapor refrigerant before being condensed flows. In addition, the loop type heat pipe is provided with a flow limitation portion for flowing the second fluid from the refrigerant condensation side toward the refrigerant un-condensation side. For example, the loop type heat pipe is suitably used for a waste heat recovery device.

1 . A loop type heat pipe in which a refrigerant circulates, comprising: 
 an evaporator located to evaporate the refrigerant by heat-exchanging with a first fluid as a heat source;    a condenser located to liquefy and condense the evaporated vapor refrigerant by heat-exchanging with a second fluid to be heated, the condenser having a refrigerant condensation side on which the condensed liquid refrigerant flows, and a refrigerant un-condensation side on which the vapor refrigerant before being condensed flows; and    a flow limitation means for flowing the second fluid from the refrigerant condensation side toward the refrigerant un-condensation side.    
   
   
       2 . The loop type heat pipe according to  claim 1 , further comprising 
 a liquid refrigerant storage portion provided to store the condensed liquid refrigerant,    wherein the flow limitation means is provided for flowing the second fluid from a side of the liquid refrigerant storage portion toward the refrigerant un-condensation side.    
   
   
       3 . The loop type heat pipe according to  claim 2 , wherein the liquid refrigerant storage portion is a part of the condenser.  
   
   
       4 . The loop type heat pipe according to  claim 1 , further comprising 
 an operation stop means for stopping the evaporation of the refrigerant in the evaporator.    
   
   
       5 . The loop type heat pipe according to  claim 4 , wherein the operation stop means is a switching valve located to open and close a passage through which the liquid refrigerant condensed in the condenser flows to the evaporator.  
   
   
       6 . The loop type heat pipe according to  claim 4 , wherein the operating stop means is a flow control means for controlling a flow amount of the first fluid flowing to the evaporator.  
   
   
       7 . The loop type heat pipe according to  claim 1 , wherein: 
 the first fluid is an exhaust gas of an engine, generated by fuel combustion in the engine;    the second fluid is a coolant used for a coolant circuit of the engine; and    the evaporator and the condenser are located to recovery waste heat from the exhaust gas.    
   
   
       8 . The loop type heat pipe according to  claim 1 , wherein: 
 the evaporator includes a plurality of tubes in which the refrigerant flows, the tubes being arranged in parallel with each other and elongated in a first direction; and    the condenser includes a plurality of tubes arranged in parallel with each other and elongated in a second direction that is parallel with the first direction.    
   
   
       9 . The loop type heat pipe according to  claim 8 , further comprising a switching valve that is located in the condenser at a lower side of the tubes of the condenser to open and close a passage through which the liquid refrigerant flows toward the evaporator.  
   
   
       10 . The loop type heat pipe according to  claim 1 , wherein: 
 the evaporator includes a plurality of tubes arranged in parallel with each other and elongated in a first direction;    the condenser includes a plurality of tubes in which the refrigerant flows, the tubes being arranged in parallel with each other and elongated in a second direction that is perpendicular to the first direction; and    the condenser is located at an upper side of the evaporator.    
   
   
       11 . The loop type heat pipe according to  claim 10 , further comprising 
 a switching valve that is located in the condenser at a downstream side of the tubes of the condenser in a refrigerant flow to open and close a passage through which the liquid refrigerant flows toward the evaporator.    
   
   
       12 . A waste heat recovery device comprising: 
 a loop-type heat pipe including an evaporator located to evaporate a refrigerant by performing a heat exchange with a first fluid, and a condenser located to cool and condense the evaporated vapor refrigerant from the evaporator;    a first fluid flowing portion in which the first fluid flows to perform heat exchange with the refrigerant in the evaporator;    a second fluid flowing portion in which the second fluid flows to perform heat exchange with the refrigerant in the condenser;    an introducing pipe for introducing the second fluid to the second fluid flowing portion; and    a discharging pipe for discharging the second fluid from the second fluid flowing portion after passing through the second fluid flowing portion, wherein:    the condenser has a refrigerant condensation side on which the condensed liquid refrigerant flows, and a refrigerant un-condensation side on which the vapor refrigerant before being condensed flows; and    the introducing pipe is connected to the second fluid flowing portion at the refrigerant condensation side of the condenser, and the discharging pipe is connected to the second fluid flowing portion at the refrigerant un-condensation side of the condenser.    
   
   
       13 . The waste heat recovery device according to  claim 12 , wherein: 
 the evaporator includes a plurality of tubes in which the refrigerant flows, the tubes being arranged in parallel with each other and elongated in a first direction; and    the condenser includes a plurality of tubes in which the refrigerant flows, the tubes being arranged in parallel with each other and elongated in a second direction that is parallel with the first direction.    
   
   
       14 . The waste heat recovery device according to  claim 13 , further comprising a switching valve that is located in the condenser at a lower side of the tubes of the condenser to open and close a passage through which the liquid refrigerant flows toward the evaporator.  
   
   
       15 . The waste heat recovery device according to  claim 12 , further comprising 
 a flow control means for controlling a flow amount of the first fluid flowing to the evaporator.    
   
   
       16 . The waste heat recovery device according to  claim 12 , wherein: 
 the evaporator includes a plurality of tubes in which the refrigerant flows, the tubes being arranged in parallel with each other and elongated in a first direction;    the condenser includes a plurality of tubes in which the refrigerant flows, the tubes being arranged in parallel with each other and elongated in a second direction that is perpendicular to the first direction; and    the condenser is located at an upper side of the evaporator.    
   
   
       17 . The waste heat recovery device according to  claim 16 , further comprising a switching valve that is located in the condenser at a downstream side of the tubes of the condenser in a refrigerant flow to open and close a passage through which the liquid refrigerant flows toward the evaporator.