Evaporative heat exchanger for cooling a refrigerant

Abstract

An evaporative heat exchanger for cooling a hot refrigerant having a core of alternatively stacked dry and wet plates. Each dry plate includes a dry side defining a plurality of dry channels in a first direction, a series of ports distributed along the dry channels, a wet side, and a refrigerant cooling section. Each wet plate includes a wet side adjacent to and cooperates with the wet side of the dry plate to define a plurality of wet channels in a second direction. The dry channels, ports, and wet channels define a labyrinth for the air flow, which evaporates the liquid contained in the wet channels resulting in a cooling of the refrigerant. The refrigerant cooling section is integral with the outboard of the dry plate and adjacent to an end section of the wet channels to provide enhanced refrigerant cooling.

1 . An evaporative heat exchanger for cooling a refrigerant, comprising:
 a dry plate having an air flow section and an integral refrigerant cooling section, wherein said airflow section includes a dry side defining a plurality of dry channels in a first direction for air flow and a wet side opposite said dry side, and a series of ports distributed along said dry channel;   a wet plate having a wet surface adjacent to and cooperates with said wet side of dry plate to define a plurality of wet channels in a second direction for air flow, wherein each said wet channel is adapted to contain an evaporative liquid and communicates with said dry channel through said ports; and   means to distribute said evaporative liquid onto said wet channels;   wherein said refrigerant cooling section includes refrigerant passageways, and is disposed outboard of said air flow section and adjacent to an open end section of each said wet channel;   whereby air introduced into said dry channels flows through said ports and through said wet channels evaporating said evaporative liquid to enhance cooling of said dry plate and said end section of said wet channels to thereby enhance cooling of said refrigerant cooling section.   
   
   
       2 . An evaporative heat exchanger for cooling a refrigerant of  claim 1 , further comprising an inlet refrigerant header in hydraulic communication with openings of said refrigerant passageways and an outlet refrigerant header in hydraulic communication with opposing openings of said refrigerant passageways. 
   
   
       3 . An evaporative heat exchanger for cooling a refrigerant of  claim 1 , wherein said refrigerant passageways have a hydraulic diameter in the range of 0.3 to 0.7 mm. 
   
   
       4 . An evaporative heat exchanger for cooling a refrigerant of  claim 1 , wherein said dry plates and said wet plates comprises copper, aluminum, or brass. 
   
   
       5 . An evaporative heat exchanger for cooling a refrigerant of  claim 1 , wherein said dry plates and said wet plates are brazed together. 
   
   
       6 . An evaporative heat exchanger for cooling a refrigerant of  claim 4 , wherein ratio for the area of the largest port opening compared to the area of the smallest port opening is in the range of 1.125 to 2.000. 
   
   
       7 . An evaporative heat exchanger for cooling a refrigerant of  claim 1 , wherein said dry plate comprises an integrated evaporative liquid distribution conduit. 
   
   
       8 . An evaporative heat exchanger for cooling a refrigerant of  claim 7 , wherein said dry plate comprises extruded copper, aluminum, or brass. 
   
   
       9 . An evaporative heat exchanger for cooling a refrigerant of  claim 1 , wherein said wet surface of wet plate comprises a texture for the wicking of said evaporative fluid. 
   
   
       10 . A plate for an evaporative heat exchange for cooling a refrigerant, comprising:
 a heat conductive plate having a dry side including an air flow section having a plurality of fins; and   a refrigerant cooling section outboard and integral with said air flow section,   wherein said refrigerant cooling section includes a plurality of passageways for refrigerant flow.   
   
   
       11 . A plate for an evaporative heat exchanger of  claim 10 , further comprising a wet side opposing said dry side;
 wherein said fins are substantially parallel and cooperation with said dry side to form a plurality of substantially parallel dry channels for air flow; and   where in said dry channels include a series of ports in hydraulic communication with said wet side.   
   
   
       12 . A plate for an evaporative heat exchanger of  claim 11 , comprises a first port upstream of air flow and a last port downstream of air flow, wherein said first port has a smaller open area than said last port. 
   
   
       13 . A plate for an evaporative heat exchanger of  claim 12 , wherein the ratio of said last port open area to said first port open area is in the range of 1.125:1 to 2.0:1.0. 
   
   
       14 . A plate for an evaporative heat exchanger of  claim 10 , wherein said passageways for refrigerant flow have a hydraulic diameter in the range of 0.3 to 0.7 mm. 
   
   
       15 . A plate for an evaporative heat exchanger of  claim 10 , further comprising an evaporative liquid distribution conduit. 
   
   
       16 . A plate for an evaporative heat exchanger of  claim 15 , further comprising copper, aluminum, or brass. 
   
   
       17 . A plate for an evaporative heat exchanger of  claim 16 , wherein said plate is extruded. 
   
   
       18 . An evaporative heat exchanger for cooling a refrigerant, comprising:
 a first dry plate having a dry side defining a plurality of dry channels in a first direction and a wet side opposite said dry side, a series of ports distributed along said dry channel, and an refrigerant cooling section comprising refrigerant passageways;   a second dry plate having a dry side defining a plurality of dry channels in a first direction and a wet side opposite said dry side, a series of ports distributed along said dry channel, and an refrigerant cooling section comprising refrigerant passageways; and   a wet plate having a wet surface adjacent to and cooperates with said wet side of said first dry plate to define a plurality of wet air flow conduits in a second direction adapted to contain an evaporative liquid, each said wet plate further having a dry surface adjacent to and cooperates with said dry side of second dry plate to define a plurality of dry air flow conduits in said first direction, wherein said wet flow conduits communicate with said dry air flow conduits said ports;   wherein said refrigerant cooling section is integral with outboard of said dry plate and adjacent to an end section of each said wet channel; thereby providing enhanced heat transfer between refrigerant in said passages and air flow through said wet channel.   
   
   
       19 . An evaporative heat exchanger for cooling a refrigerant of  claim 18 , where said dry air flow conduit has a hydraulic diameter of 2.0 to 5.0 mm. 
   
   
       20 . An evaporative heat exchanger for cooling a refrigerant of  claim 18 , where said wet air flow conduit has a hydraulic diameter of 2.0 to 7.5 mm.