Evaporative cooler and desiccant assisted vapor compression AC system

Abstract

An air conditioning system includes an evaporator assembly and a condenser assembly. A first portion of the exhaust airstream leaves the condenser and enters a primary channel of an evaporative cooler assembly. Water evaporates from the evaporative cooler tubes and creates a moisture-laden airstream. A plurality of apertures in the evaporative cooler tubes bleeds the moisture-laden airstream into a secondary channel defined within the evaporative cooler tubes. The heat drawn from the air in the primary channel produces an evaporatively cooled airstream that enters a desiccant wheel. A solid desiccant material within the desiccant wheel absorbs moisture from the evaporatively cooled airstream to produce a dehumidified airstream that enters the evaporator assembly. A second portion of the exhaust airstream is directed through a heater and then into the desiccant wheel to provide heat for regeneration of the solid desiccant material.

1 . An air conditioning system comprising;
 an evaporator assembly including a plurality of evaporator tubes for carrying a refrigerant and an evaporator fan for moving a dehumidified airstream across said evaporator tubes for transferring heat from the dehumidified airstream to the refrigerant to evaporate the refrigerant and to produce a conditioned airstream,   a condenser assembly including a plurality of condenser tubes in fluid communication with said evaporator tubes and a condenser fan for moving ambient air over said condenser tubes for transferring heat from the refrigerant to the ambient air to condense the refrigerant and to produce an exhaust airstream,   an evaporative cooler assembly defining a primary channel for receiving an incoming airstream and for producing an evaporatively cooled airstream, and   a desiccant wheel including a solid desiccant material and a housing supporting said solid desiccant material and a first air inlet in airflow communication with said evaporative cooler assembly for receiving the evaporatively cooled airstream and for directing the evaporatively cooled airstream through a first sector of said housing to cause an exothermic reaction with said solid desiccant material to dry the evaporatively cooled airstream to produce the dehumidified airstream and including a first outlet in airflow communication with said evaporator assembly for directing the dehumidified airstream over said evaporator tubes.   
   
   
       2 . A system as set forth in  claim 1  wherein said condenser tubes are spaced apart from oneanother defining a condenser air passage therebetween for receiving the ambient air and for discharging the exhaust airstream and said evaporative cooler assembly is in airflow communication with said condenser air passage for receiving at least a first portion of the exhaust airstream and for cooling the first portion of the exhaust airstream to produce the evaporatively cooled airstream. 
   
   
       3 . A system as set forth in  claim 2  including a first conduit connecting said condenser air passage to said evaporative cooler assembly in airflow communication for directing at least the first portion of the exhaust airstream to the primary channel of the evaporative cooler. 
   
   
       4 . A system as set forth in  claim 3  wherein said evaporative cooler assembly includes;
 a plurality of evaporative cooler tubes extending vertically defining a secondary channel therein and spaced apart from one another defining said primary channel extending perpendicularly therebetween for receiving the first fraction of the exhaust airstream,   a water tank disposed about an end of said evaporative cooler tubes and said evaporative cooler tubes extending upwardly from said water tank and including a wicking coating extending thereon for wicking water by capillary action from said water tank into contact with said primary channel for evaporation into a moisture-laden airstream to draw the latent heat of vaporization from the first fraction of the exhaust airstream to produce the evaporatively cooled airstream carried by said primary channel, and   a plurality of apertures disposed along said evaporative cooler tubes for bleeding the moisture-laden airstream from said primary channel into said secondary channel for discharge from said evaporative cooler.   
   
   
       5 . A system as set forth in  claim 4  wherein said evaporative cooler assembly includes a plurality of fins extending back and forth between said tubes extending parallel with said primary channel. 
   
   
       6 . A system as set forth in  claim 2  including a second conduit in airflow communication with said condenser air passage and said desiccant wheel including a second air inlet connected with said second conduit for airflow communication with said condenser air passage for directing at least a second portion of the exhaust airstream through a second sector of said housing to cause an endothermic reaction with said solid desiccant material to dry said solid desiccant material and said desiccant wheel including a second air outlet for discharging the second fraction of the exhaust airstream. 
   
   
       7 . A system as set forth in  claim 6  including a heater disposed along said second conduit between said condenser air passage and said second air inlet for heating the second portion of the exhaust airstream. 
   
   
       8 . A system as set forth in  claim 6  wherein said housing of said desiccant wheel includes a pair of end plates spaced apart and a plurality of desiccant tubes extending therebetween supporting said solid desiccant material therewithin and a pair of trunnions each extending from one of said end plates defining an axis and supporting said desiccant wheel for rotation about said axis to alternately move said solid desiccant material between said first and second sectors to successively expose said solid desiccant material to the second portion of the exhaust airstream and to the evaporatively cooled airstream. 
   
   
       9 . An air conditioning system comprising;
 an evaporator assembly including a plurality of evaporator tubes for carrying a refrigerant therein and said evaporator tubes being spaced apart from oneanother defining a evaporator air passage therebetween for receiving a dehumidified airstream to flow over said evaporator tubes for transferring heat from the dehumidified airstream to the refrigerant to evaporate the refrigerant within said evaporator tubes and to produce a conditioned airstream within said evaporator air passage,   a condenser assembly including a plurality of condenser tubes in fluid communication with said evaporator tubes and spaced apart from oneanother defining a condenser air passage therebetween and a condenser fan for moving ambient air through said condenser air passage over said condenser tubes for transferring heat from the refrigerant to the ambient air to condense the refrigerant within said condenser tubes and to produce an exhaust airstream within said condenser air passage,   an evaporative cooler assembly including a plurality of evaporative cooler tubes extending vertically defining a secondary channel therein and spaced apart from one another defining a primary channel therebetween for receiving a first portion of the exhaust airstream and for producing an evaporatively cooled airstream and a moisture-laden airstream and said evaporative cooler tubes including a plurality of apertures for bleeding the moisture-laden airstream from said primary channel into said secondary channel,   a first conduit in airflow communication with said condenser air passage and said, primary channel of said evaporative cooler for directing the first portion of the exhaust airstream to said primary channel,   a desiccant wheel including a solid desiccant material and a housing supporting said solid desiccant material and a first air inlet in airflow communication with said primary channel of said evaporative cooler assembly for receiving the evaporatively cooled airstream and for directing the evaporatively cooled airstream through a first sector of said housing to cause an exothermic reaction with said solid desiccant material to dry the evaporatively cooled airstream to produce the dehumidified airstream and including a first outlet in airflow communication with said evaporator assembly for directing the dehumidified airstream over said evaporator tubes,   said desiccant wheel including a second air inlet for receiving a second portion of the exhaust airstream and for directing the second portion of the exhaust airstream through a second sector of said housing to cause an endothermic reaction with said solid desiccant material to dry said solid desiccant material and said desiccant wheel including a second air outlet for discharging the second fraction of the exhaust airstream,   a second conduit in airflow communication with said condenser air passage and said second air inlet for directing the second portion of the exhaust airstream to said second sector of said housing, and   an exhaust flow divider connected in airflow communication between said condenser air passage and said first and second conduits for dividing the exhaust airstream into the first and second portions.   
   
   
       10 . An air conditioning system as set forth in  claim 9  including a heater disposed along said second conduit in airflow communication between said condenser air passage and said second air inlet for heating the second portion of the exhaust airstream. 
   
   
       11 . An air conditioning system as set forth in  claim 9  including a water tank disposed about an end of said evaporative cooler tubes and said evaporative cooler tubes including a wicking coating extending thereon for wicking water by capillary action from said water tank into contact with said primary channel for evaporation into the moisture-laden airstream to draw the latent heat of vaporization from the first fraction of the exhaust airstream to produce the evaporatively cooled airstream carried by said primary channel. 
   
   
       12 . An air conditioning system as set forth in  claim 9  wherein said housing of said desiccant wheel is rotatably supported about an axis for rotation about said axis to alternately move said solid desiccant material between said first and second sectors to successively expose said solid desiccant material to the second portion of the exhaust airstream and to the evaporatively cooled airstream. 
   
   
       13 . A system as set forth in  claim 9  including an evaporator fan for moving the dehumidified airstream through said evaporator air passage over said evpaorator tubes. 
   
   
       14 . An air conditioning system comprising;
 an evaporator assembly including a plurality of evaporator tubes for carrying a refrigerant and an evaporator fan for moving a dehumidified airstream across said evaporator tubes for transferring heat from the dehumidified airstream to the refrigerant to evaporate the refrigerant and to produce a conditioned airstream,   a compressor in fluid communication with said evaporator tubes for compressing the evaporated refrigerant to produce a superheated vapor,   a condenser assembly including a plurality of condenser tubes in fluid communication with said compressor and spaced apart from oneanother defining a condenser air passage therebetween and a condenser fan for moving ambient air through said condenser air passage over said condenser tubes for transferring heat from the superheated vapor to the ambient air to condense the superheated vapor into a liquid refrigerant and to produce an exhaust airstream,   an expansion device in fluid communication with said condenser tubes and with said evaporator tubes for decreasing the pressure on the liquid to produce a sub-cooled liquid refrigerant for supply back to said evaporator tubes,   an evaporative cooler assembly including a plurality of evaporative cooler tubes extending vertically and spaced apart from one another and including a plurality of fins extending back and forth between said evaporative cooler tubes defining a primary channel extending perpendicularly between said evaporative cooler tubes and being in airflow communication with said condenser air passage for receiving a first portion of the exhaust airstream for producing an evaporatively cooled airstream,   said evaporative cooler tubes including a plurality of internal dividers extending within said tubes defining a secondary channel extending perpendicularly to said primary channel,   said evaporative cooler assembly including a water tank disposed about an end of said evaporative cooler tubes,   said evaporative cooler tubes extending upwardly from said water tank and including a wicking coating extending thereon for wicking water by capillary action from said water tank into contact with said primary channel for evaporation into a moisture-laden airstream to draw the latent heat of vaporization from the first fraction of the exhaust airstream to produce the evaporatively cooled airstream carried by said primary channel,   said evaporative cooler tubes including a plurality of apertures for bleeding the moisture-laden airstream from said primary channel into said secondary channel for discharge from said evaporative cooler,   a desiccant wheel including a housing having a pair of end plates spaced apart and a plurality of desiccant tubes extending therebetween and a pair of trunnions each extending from one of said end plates defining an axis,   said desiccant wheel including a solid desiccant material extending within each of said desiccant tubes,   said desiccant wheel including a first air inlet in airflow communication with said primary channel of said evaporative cooler for receiving the evaporatively cooled airstream and for directing the evaporatively cooled airstream through a first sector of said desiccant tubes to cause an exothermic reaction with said solid desiccant material to dry the evaporatively cooled airstream to produce the dehumidified airstream and including a first air outlet in airflow communication with said evaporator assembly for directing the dehumidified airstream over said evaporator tubes,   said desiccant wheel including a second air inlet in airflow communication with said condenser air passage for receiving a second portion of the exhaust airstream and for directing the second portion of the exhaust airstream through a second sector of said desiccant tubes to cause an endothermic reaction with said solid desiccant material to dry said solid desiccant material and including a second air outlet for discharging second portion of the exhaust airstream,   said desiccant wheel being supported by said trunnions for rotation about said axis to alternately move said solid desiccant material between said first and second sectors to successively expose said solid desiccant material to said desiccant regenerating airstream and to said ambient air,   a first conduit in airflow communication with said condenser air passage and said primary channel of said evaporative cooler for directing the first portion of the exhaust airstream to said primary channel,   a second conduit in airflow communication with said condenser air passage and second air inlet for directing the second portion of the exhaust airstream to said second sector of said desiccant tubes,   an exhaust flow divider connected in airflow communication between said condenser air passage and said first and second conduits for dividing the exhaust airstream into the first portion and the second portion, and   a heater in airflow communication between said exhaust flow divider and said second air inlet of said desiccant wheel for receiving the second portion of the exhaust airstream and for adding heat to the second portion of the exhaust airstream.