Rear door heat exchanger

Abstract

A rear door heat exchanger adapted to be mounted on the rear of a rack or other arrangement of heat-generating electronic equipment, and to cool air which passes therethrough when the rear door heat exchanger is in use. It comprises an upstream header and a downstream header with a multiplicity of substantially parallel microchannels extending between and in fluid communication with both the upstream header and the downstream header. Thus both headers are common to the microchannels of the said multiplicity of microchannels.

1 . A rear door heat exchanger adapted to be mounted on a rear of a rack or other arrangement of heat-generating electronic equipment, and to cool air which passes therethrough when the rear door heat exchanger is in use, the exchanger comprising:
 an upstream header;   a downstream header; and   a multiplicity of substantially parallel microchannels extending between and in fluid communication with both of the upstream header and the downstream header so such that both of the upstream and downstream headers are common to the microchannels of the multiplicity of microchannels.   
     
     
         2 . A rear door heat exchanger according to  claim 1 , in which the microchannels extend in a direction which has at least a component in the vertical direction when the rear door heat exchanger is mounted ready for use. 
     
     
         3 . A rear door heat exchanger according to  claim 2 , in which the microchannels are upright when the rear door heat exchanger is mounted ready for use. 
     
     
         4 . A rear door heat exchanger according  claim 1 , wherein the upstream header is an upper header and the downstream header is a lower header. 
     
     
         5 . A rear door heat exchanger according to  claim 1 , wherein each microchannel extends from the position where it is open to the upstream header to the position where it opens into the downstream header in a single pass without meandering. 
     
     
         6 . A rear door heat exchanger according to  claim 1 , wherein each microchannel has an internal cross-sectional diameter or width of less than 3.5 mm. 
     
     
         7 . A rear door heat exchanger according to  claim 6 , wherein the internal cross-sectional diameter or width of each microchannel is in the range from substantially 0.5 mm to substantially 3.0 mm. 
     
     
         8 . A rear door heat exchanger according to  claim 7 , wherein the internal cross-sectional diameter or width of each microchannel is substantially 1.1 mm. 
     
     
         9 . A rear door heat exchanger according to  claim 7 , wherein the internal cross-sectional diameter or width of each microchannel is substantially 0.8 mm. 
     
     
         10 . A rear door heat exchanger according to  claim 1 , wherein the interior of at least one of the microchannels is rifled to give better heat transfer between the coolant and the microchannels. 
     
     
         11 . A rear door heat exchanger according to  claim 1 , wherein the microchannels are provided by tubes. 
     
     
         12 . A rear door heat exchanger according to  claim 1 , further comprising strips of material extending transversely of and in thermal contact with the microchannels. 
     
     
         13 . (canceled) 
     
     
         14 . (canceled)