Heat exchange apparatus

Abstract

A heat exchange apparatus includes a heat exchange circuit which is provided with an evaporator which is connected in output to a condenser, which is connected, in output, by way of the interposition of expansion elements to the evaporator and in which there is at least one regenerative exchanger between the evaporator and the condenser. The apparatus includes adjustment valve elements between the outlet of the condenser and the inlet of the evaporator. Sensor elements are further provided which are adapted to measure at least one thermodynamic parameter of the exchange fluid at preset points of the circuit and control elements are further provided which are connected to the sensor elements and are configured to calculate, using measurements supplied by the sensor elements, the instantaneous efficiency and a reference efficiency of the regenerative exchanger.

1 - 16 . (canceled) 
     
     
         17 . A heat exchange apparatus comprising: a heat exchange circuit which is passed through by a heat exchange fluid and is provided with an evaporator which is connected in output, by way of the interposition of a compressor, to a condenser, which is connected in output, by way of the interposition of expansion means, to said evaporator, between said evaporator and said condenser there being at least one regenerative exchanger for an exchange of heat between a vapor-phase exchange fluid that exits from said evaporator and a liquid-phase exchange fluid that exits from said condenser, and further comprising, between an outlet of said condenser and an inlet of said evaporator, adjustment valve means for a flow of said exchange fluid, sensor means being provided which are adapted to measure at least one thermodynamic parameter of said exchange fluid at preset points of said circuit and control means being provided which are connected to said sensor means and are configured to calculate, using measurements supplied by said sensor means, an instantaneous efficiency of said regenerative exchanger and a reference efficiency of said regenerative exchanger, said control means being adapted to act on said adjustment valve means in order to vary their degree of opening, at least on the basis of a difference between the instantaneous efficiency and the reference efficiency of said regenerative exchanger. 
     
     
         18 . The apparatus according to  claim 17 , wherein said circuit comprises at least one liquid line which connects the outlet of said condenser with the inlet of said evaporator and passes through said regenerative exchanger, said expansion means comprising at least one adjustable expansion valve, which is interposed along said liquid line between said regenerative exchanger and said evaporator, said adjustment valve means comprising at least one first adjustment valve which is constituted by said at least one adjustable expansion valve. 
     
     
         19 . The apparatus according to  claim 18 , wherein said adjustment valve means comprise at least one second adjustment valve which is adapted to adjust the flow of the liquid-phase exchange fluid that passes through said regenerative exchanger. 
     
     
         20 . The apparatus according to  claim 19 , wherein said at least one second adjustment valve is interposed along said liquid line. 
     
     
         21 . The apparatus according to  claim 19 , further comprising a bypass line which connects a first section of said liquid line located upstream of said regenerative exchanger to a second section of said liquid line located downstream of said regenerative exchanger, said at least one second adjustment valve being interposed along said bypass line. 
     
     
         22 . The apparatus according to  claim 21 , wherein said second adjustment valve comprises a variable-aperture three-way valve which is connected, with two ways, along said liquid line and, with a third way, to said bypass line. 
     
     
         23 . The apparatus according to  claim 21 , wherein said at least one second adjustment valve comprises a variable-aperture two-way valve interposed along said bypass line. 
     
     
         24 . The apparatus according to  claim 21 , wherein said at least one second adjustment valve comprises a two-way valve interposed along said liquid line, upstream of said regenerative exchanger. 
     
     
         25 . The apparatus according to  claim 17 , wherein said circuit comprises at least one steam line which connects the outlet of said evaporator with the inlet of said condenser and passes through said regenerative exchanger, said compressor being interposed along said steam line, between said regenerative exchanger and said condenser, said sensor means comprising a first temperature sensor which is arranged along said steam line between said regenerative exchanger and said compressor, a second temperature sensor arranged along said liquid line upstream of said regenerative exchanger, a third temperature sensor arranged along said liquid line downstream of said regenerative exchanger, and a pressure sensor arranged along said steam line between said evaporator and said compressor. 
     
     
         26 . The apparatus according to  claim 25 , wherein said sensor means comprise a fourth temperature sensor which is arranged along said steam line between said evaporator and said regenerative exchanger. 
     
     
         27 . The apparatus according to  claim 17 , wherein said control means are configured to calculate said reference efficiency, by requiring a superheating of said exchange fluid at said evaporator to be comprised substantially between 0 and 5 K. 
     
     
         28 . The apparatus according to  claim 18 , wherein said control means are configured to actuate said adjustable expansion valve on the basis of the difference between the instantaneous efficiency and the reference efficiency of said regenerative exchanger. 
     
     
         29 . The apparatus according to  claim 19 , wherein said control means are configured to actuate said adjustable expansion valve, on the basis of the difference between actual superheating of said heat exchange fluid at the outlet of said evaporator or at the inlet of said compressor, which is determined using the measurements of said sensor means, and a preset reference value for the superheating of said exchange fluid at said evaporator, and to actuate said second adjustment valve, on the basis of the difference between the instantaneous efficiency and the reference efficiency of said regenerative exchanger. 
     
     
         30 . A method for adjusting a heat exchange apparatus of the type comprising a heat exchange circuit which is passed through by a heat exchange fluid and is provided with an evaporator which is connected in output, by way of the interposition of a compressor, to a condenser, which is connected in output, by way of the interposition of expansion means, to said evaporator and with the interposition, between said evaporator and said condenser, of at least one regenerative exchanger for heat exchange between the vapor-phase exchange fluid that exits from said evaporator and the liquid-phase exchange fluid that exits from said condenser, and further comprising the steps of performing a measurement of at least one thermodynamic parameter of said exchange fluid at preset points of said circuit, calculating, using the measurements made, an instantaneous efficiency and a reference efficiency of said regenerative exchanger, calculating a difference between a calculated value of the instantaneous efficiency of said regenerative exchanger and a calculated value of the reference efficiency of said regenerative exchanger, and varying a degree of opening of adjustment valve means interposed between an outlet of the condenser and an inlet of the evaporator on the basis of a calculated value of the difference between the instantaneous efficiency and the reference efficiency of said regenerative exchanger. 
     
     
         31 . The method according to  claim 30 , wherein the instantaneous efficiency is calculated using the measurement at least of a temperature of said liquid-phase exchange fluid in input to said regenerative exchanger and of a temperature of said vapor-phase exchange fluid in output from said regenerative exchanger. 
     
     
         32 . The method according to  claim 30 , wherein the reference efficiency of said regenerative exchanger is calculated by requiring a superheating of said exchange fluid at said evaporator to be comprised between 0 and 5 K.