Cooling system with microchannel heat exchanger

Abstract

A heat exchange system including at least one first heat exchanger having a closed circuit for cooling fluid, a least one fan arrangement operable to cause air to pass through the first heat exchanger, and, at least one air cooler located upstream of the first heat exchanger, wherein the first heat exchanger includes a microchannel heat exchanger.

1 .- 15 . (canceled) 
     
     
         16 . A heat exchange system comprising:
 at least one first heat exchanger having a closed circuit for cooling fluid;   at least one air cooler located upstream of the at least one first heat exchanger; and   at least one fan arrangement operable to causes air to pass through the at least one first heat exchanger and the at least one air cooler,   wherein the air cooler comprises a moisture absorbent material in the form of moisture absorbent pads that are, in use, maintained moist such that air passing through the cooler is cooled by the action of evaporation prior to passing over a portion of the closed circuit of the first heat exchanger and the at least one first heat exchanger comprises a microchannel heat exchanger.   
     
     
         17 . A heat exchange system according to  claim 16 , wherein the cooling fluid is supplied through a substantially horizontal supply header and the cooling fluid is passed from the closed circuit microchannel heat exchanger through a substantially horizontal return header. 
     
     
         18 . A heat exchange system according to  claim 16 , wherein the supply header is located at or near the top of the closed circuit microchannel heat exchanger and the return header is located at or near the bottom of the closed circuit microchannel heat exchanger, such that cooling fluid passes into the closed circuit microchannel heat exchanger at or near the top and passes once through the closed circuit microchannel heat exchanger by the action of gravity and passes out through the return header at or near the bottom of the closed circuit microchannel heat exchanger. 
     
     
         19 . A heat exchange system according to  claim 16 , wherein a supply header and a return header are located at or near vertical sides of the closed circuit microchannel heat exchanger. 
     
     
         20 . A heat exchange system according to  claim 16 , wherein cooling fluid flows in through the supply header and passes through the fluid passages of the closed circuit microchannel heat exchanger before passing to the return header, such that the cooling fluid flows out of the return header. 
     
     
         21 . A heat exchange system according to  claim 16 , wherein the microchannel heat exchanger comprises fluid passages that extend between vertical sides of the microchannel heat exchanger. 
     
     
         22 . A heat exchange system according to  claim 16 , further comprising a second microchannel heat exchanger. 
     
     
         23 . A heat exchange system according to  claim 16 , wherein the first and second microchannel heat exchangers are aligned substantially in series, with respect to air flow, such that the first and second microchannel heat exchangers form a microchannel heat exchanger stack. 
     
     
         24 . A heat exchange system according to  claim 16 , wherein the first microchannel heat exchanger is arranged in series with one or more further first microchannel heat exchangers. 
     
     
         25 . A heat exchange system according to  claim 16 , wherein the air cooler, when in use, comprises a fan arrangement that causes air to pass through the air cooler and the one or more heat exchangers. 
     
     
         26 . A heat exchange system according to  claim 16 , wherein the first closed circuit microchannel heat exchanger is configured in a substantially cross-sectional tubular arrangement. 
     
     
         27 . A heat exchange system according to  claim 16 , wherein the first fan arrangement is operable to cause air to pass longitudinally through the internal space of the substantially tubular arrangement of the first closed circuit microchannel heat exchanger. 
     
     
         28 . A heat exchange system according to  claim 16 , wherein air also passes through the walls of the substantially tubular arrangement. 
     
     
         29 . A heat exchange system according to  claim 16 , where further comprising a second microchannel heat exchanger having a closed circuit for cooling fluid, wherein the second microchannel heat exchanger is arranged with first microchannel heat exchanger such that they form a substantially cross-sectional tubular arrangement with an internal space through which air passes. 
     
     
         30 . A heat exchange system according to  claim 16 , wherein, during use, the cooling fluid in the closed circuit microchannel heat exchanger operates at a substantially higher pressure than cooling fluid in a conventional tube and fin closed circuit heat exchanger.