Exhaust heat recovery apparatus

Abstract

An exhaust heat recovery apparatus includes an evaporation unit, a condensation unit, an evaporation-side communication part and a condensation-side communication part. The evaporation unit is disposed in an exhaust gas passage through which an exhaust gas flows and performs heat exchange between the exhaust gas and an operation fluid flowing therein, thereby evaporating the operation fluid. The condensation unit is disposed in a coolant passage through which an engine coolant flows and performs heat exchange between the operation fluid and the engine coolant, thereby condensing the operation fluid. The evaporation-side communication part connects the evaporation unit and the condensation unit for introducing evaporated operation fluid to the condensation unit. The condensation-side communication part connects the condensation unit and the evaporation unit for introducing condensed operation fluid to the evaporation unit. The condensation-side communication part is provided with a throttle part.

1 . An exhaust heat recovery apparatus comprising:
 an evaporation unit to be disposed in an exhaust gas passage through which an exhaust gas exhausted. from an engine flows, for performing heat exchange between the exhaust gas and an operation fluid flowing therein, thereby evaporating the operation fluid;   a condensation unit to be disposed in a coolant passage through which an engine coolant flows, for performing heat exchange between the engine coolant and the operation fluid that has been evaporated in the evaporation unit, thereby condensing the operation fluid;   an evaporation-side communication part connecting the evaporation unit and the condensation unit for introducing the operation fluid from the evaporation unit to the condensation unit;   a condensation-side communication part connecting the condensation unit and the evaporation unit for introducing the operation fluid from the condensation unit to the evaporation unit; and   a throttle part disposed in the condensation-side communication part.   
   
   
       2 . The exhaust heat recovery apparatus according to  claim 1 , wherein the throttle part includes a fixed throttle. 
   
   
       3 . The exhaust heat recovery apparatus according to  claim 2 , wherein the fixed throttle is provided by partly reducing a passage area of the condensation- side communication part. 
   
   
       4 . The exhaust heat recovery apparatus according to  claim 1 , wherein the throttle part includes a variable throttle that is configured to vary an opening degree of an orifice through which the operation fluid flows in accordance with a temperature of the operation fluid. 
   
   
       5 . The exhaust heat recovery apparatus according to  claim 4 , wherein the variable throttle is configured such that the opening degree is reduced in accordance with an increase in the temperature of the operation fluid. 
   
   
       6 . An exhaust heat recovery apparatus comprising:
 an evaporation unit to be disposed in an exhaust gas passage through which an exhaust gas exhausted from an engine flows, for performing heat exchange between the exhaust gas and an operation fluid flowing therein, thereby evaporating the operation fluid;   a condensation unit to be disposed in a coolant passage through which an engine coolant flows, for performing heat exchange between the engine coolant and the operation fluid that has been evaporated in the evaporation unit, thereby condensing the operation fluid;   an evaporation-side communication part connecting the evaporation unit and the condensation unit and defines a passage for introducing the operation fluid from the evaporation unit to the condensation unit; and   a condensation-side communication part connecting the condensation unit and the evaporation unit and defines a passage for introducing the operation fluid from the condensation unit to the evaporation unit, wherein the condensation-side communication part includes a throttle portion that has a reduced passage area.