System and method for operating a heat engine from a closed circuit of refrigerant fluid allowing recovery of heat energy from an outer fluid

Abstract

The present invention relates to a heat engine integrating a refrigerant fluid in a closed circuit and intended to undergo changes in pressure and temperature, characterized in that the circuit comprises at least: one evaporation tank ( 4 ) positioned in contact with a fluid, outside the engine, moving in a nozzle ( 3 ), one liquefier ( 11 ) in contact with a fluid capable of absorbing heat and associated with a conduit allowing the liquefied refrigerant fluid to return into the tank ( 4 ), and at least one power turbine ( 15 ), positioned between the liquefier ( 11 ) and the tank ( 4 ), and one compressor ( 9 ) downstream from the tank ( 4 ) in the circuit and arranged for controlling the temperature of the refrigerant fluid by controlling the suction of the evaporated refrigerant fluid, and in that the refrigerant fluid remains at a pressure and temperature of saturating vapor on the whole of the circuit.

1 . A heat engine comprising at least one closed circuit integrating a refrigerant fluid capable of undergoing changes in pressure and temperature, the closed circuit comprises at least:
 one first portion forming an evaporation tank positioned so as to be in contact with a fluid, outside the engine, moving in a nozzle, intended to allow evaporation of the refrigerant fluid at a clean evaporator,   one second portion forming a liquefier in contact with a fluid capable of absorbing heat and intended to allow liquefaction of the refrigerant fluid, at least one conduit allowing the liquefied refrigerant fluid to return into the tank of the first portion, and   one third portion, positioned between the first portion and the second portion, comprising at least one power turbine actuated by the movement of the evaporated refrigerant fluid in the circuit, and   one compressor positioned downstream from the first portion relatively to the direction of motion of the refrigerant fluid in the circuit and arranged in order to control the temperature of the refrigerant fluid at the outlet of at least one evaporation tank while controlling the suction of the evaporated refrigerant fluid,   
       and in that the refrigerant fluid participating in heat transfer remains maintained at a saturating vapor pressure and at the corresponding temperature on the whole of the circuit. 
     
     
         2 . The heat engine according to  claim 1 , the fluid outside the engine is an ambient gas, the first portion of the circuit ensuring evaporation of the refrigerant fluid concomitantly with a lowering of the temperature of the outer fluid right down to a temperature strictly above the freezing or crystallization temperature of the water likely to be in suspension in the ambient gas, and in that the circuit also comprises at least:
 one dehydrating filter positioned downstream from the first portion of the circuit relatively to the direction of motion of the ambient gas in the nozzle, in order to drive the gas which has carried out a heat transfer towards the refrigerant fluid of the first portion of the circuit, and   one fourth portion of the circuit forming an evaporation tank positioned so as to be in contact with the air moving in the nozzle, intended to allow evaporation of the refrigerant fluid at a clean evaporator by carrying out a heat exchange towards the refrigerant fluid at temperatures below the freezing or crystallization temperature of the water in suspension in the ambient gas, this fourth portion being positioned downstream from the dehydrating filter relatively to the direction of movement of the ambient gas in the nozzle.   
     
     
         3 . The heat engine according to  claim 1 , the fluid capable of absorbing heat in the liquefier is formed by a coolant fluid moving in a clean closed circuit which allows absorption of heat of the refrigerant fluid at the liquefier on the one hand and provision of heat to a refrigerant fluid intended to be evaporated at an evaporator on the other hand. 
     
     
         4 . The heat engine according to  claim 1 , the fluid capable of absorbing heat in the liquefier is formed by the refrigerant fluid moving in a parallel portion of the circuit and flowing from a fourth or fifth portion of the circuit forming an evaporation tank positioned so as to be in contact with the fluid, outside the engine, moving in the nozzle, intended to allow evaporation of the refrigerant fluid at a clean evaporator, this fourth or fifth portion being positioned downstream from the first portion of the circuit relatively to the direction of motion of the outer fluid in the nozzle, the refrigerant fluid evaporating at a temperature below the temperature of the refrigerant fluid flowing from the tank of the first portion being set into motion by a compressor positioned downstream from the liquefier relatively to the direction of motion of the fluid in the circuit. 
     
     
         5 . The heat engine according to  claim 1 , the engine integrates at least one auxiliary heating device in order to increase the temperature of the refrigerant fluid at the outlet and/or at the inlet of at least one turbine and/or compressor, and in that the auxiliary heating device is associated with a device for injecting liquid refrigerant fluid in order to maintain a saturating vapor pressure and avoid the formation of a dry vapor. 
     
     
         6 . The heat engine according to  claim 1 , at least one component capable of operating with heat losses is positioned in an adiabatic enclosure open in the portion of the nozzle located upstream from at least the first portion of the circuit relatively to the direction of motion of the outer fluid in the nozzle. 
     
     
         7 . The heat engine according to  claim 1 , the motion of the fluid, outside the engine, in the nozzle, involves a turbo-compressor. 
     
     
         8 . A method for operating a heat engine according to  claim 1 , the method comprises cyclically:
 a step for vaporizing the refrigerant fluid in a tank of a first portion of the circuit subsequent to at least one heat transfer from a fluid outside the engine,   a suction step by a compressor of the refrigerant fluid vaporized in a tank of a first portion of the circuit,   a step for actuating a power turbine by displacing the refrigerant fluid vaporized in the circuit,   a step for liquefying the refrigerant fluid in the second portion of the circuit forming the liquefier subsequent to at least one heat transfer towards a fluid used as a coolant,   a step for returning the liquefied refrigerant fluid into a tank of the first portion of the circuit.   
     
     
         9 . The method for operating a heat engine according to  claim 8 , the fluid used as a coolant being the refrigerant fluid moving in a parallel portion of the circuit, the method also comprises:
 a step for vaporizing the refrigerant fluid in a tank of a fourth or fifth portion of the circuit subsequent to at least one heat transfer from a fluid outside the engine concomitantly with the step of vaporization of the refrigerant fluid in the first portion of the circuit, the vaporization being carried out at a temperature less than that of the vaporization in the first portion of the circuit,   a step for suction by the compressor of the refrigerant fluid vaporized in a tank of a fourth or fifth portion of the circuit,   a step for absorption of heat from the refrigerant fluid during liquefaction in the liquefier by the refrigerant fluid vaporized in a tank of a fourth or fifth portion of the circuit,   a step for mixing, at the compressor, the refrigerant fluid vaporized in a tank of a fourth or fifth portion of the circuit, with the vaporized refrigerant fluid in another portion of the circuit in order to integrate the circuit of the vaporized refrigerant fluid into the first portion of the circuit, and   a step for returning the liquefied refrigerant fluid into a tank of the fourth or fifth portion of the circuit.   
     
     
         10 . The method for operating a heat engine according to  claim 8 , the method also comprises at least:
 one step for heating the evaporated refrigerant fluid moving in the circuit, and/or   one step for injecting liquefied refrigerant fluid into evaporated refrigerant fluid moving in the circuit.