Heat exchanger and air conditioning system

Abstract

A heat exchanger for exchanging heat under the ground or water includes an outer pipe ( 51 ) to be installed under the ground or water; and a cooling heat-transfer pipe ( 52 ) which is inserted into the outer pipe ( 51 ), and which dissipates heat from refrigerant injected thereto. A heat medium is sealed in the outer pipe ( 51 ). The outer pipe ( 51 ) and the cooling heat-transfer pipe ( 52 ) are arranged so that the liquid heat medium is held between an inner wall surface of the outer pipe ( 51 ) and an outer wall surface of the cooling heat-transfer pipe ( 52 ).

1 . A heat exchanger, comprising:
 an outer pipe ( 51 ) to be installed under the ground or water;   a cooling heat-transfer pipe ( 52 ) which is inserted into the outer pipe ( 51 ), and which dissipates heat from refrigerant injected thereto; and   a heat medium sealed in the outer pipe ( 51 ),   wherein heat is dissipated by using a change in phase of the heat medium;   the outer pipe ( 51 ) and the cooling heat-transfer pipe ( 52 ) are arranged so that the liquid heat medium is held between an inner wall surface of the outer pipe ( 51 ) and an outer wall surface of the cooling heat-transfer pipe ( 52 ).   
     
     
         2 . The heat exchanger of  claim 1 , wherein
 the cooling heat-transfer pipe ( 52 ) contacts the inner wall surface of the outer pipe ( 51 ) for heat exchange.   
     
     
         3 . The heat exchanger of  claim 1 , wherein
 the cooling heat-transfer pipe ( 52 ) extends from one end of the outer pipe ( 51 ) to the other end.   
     
     
         4 . The heat exchanger of  claim 1 , wherein,
 in the outer pipe ( 51 ), a wick ( 90 ) is provided along the inner wall surface of the outer pipe ( 51 ).   
     
     
         5 . The heat exchanger of  claim 1 , wherein
 grooves ( 100 ) for holding the heat medium by surface tension are formed in the inner wall surface of the outer pipe ( 51 ).   
     
     
         6 . The heat exchanger of  claim 1 , further comprising:
 a heating heat-transfer pipe ( 80 ) which is inserted into the outer pipe ( 51 ), and which evaporates refrigerant injected thereto.   
     
     
         7 . The heat exchanger of  claim 1 , wherein
 the cooling heat-transfer pipe ( 52 ) is formed in coiled shape.   
     
     
         8 . An air conditioning system, comprising:
 the heat exchanger of  claim 1  to perform a refrigeration cycle.