Coolant Distribution System For A Rack Having A Rear-Door Heat Exchanger

Abstract

One embodiment of the invention provides a rack assembly for cooling a computer system. A rack provides support for one or more columns of heat-generating electronic devices. Device fans move air from an air inlet side of the rack through the devices and through an air outlet side of the rack. A unitary door has a support frame spanning the air outlet side of the rack and hingedly coupling the door to a rear vertical edge of the rack. The unitary door includes an air-to-liquid heat exchanger panel spanning an air outlet passage inside the support frame so that substantially all of the air passing through the air outlet side of the rack must pass through the heat exchanger panel. The air outlet passage has a cross-sectional area that is substantially equal to or greater than the cross-sectional area of the one or more columns of heat-generating devices. A coolant circulation system includes a coolant distribution unit for chilling liquid coolant, a supply hose placing the coolant distribution unit in fluid communication with an inlet manifold of the air-to-liquid heat exchanger, and a return hose placing an outlet manifold of the air-to-liquid heat exchanger in fluid communication with the coolant distribution unit. The supply hose and return hose are routed outside the cross-sectional area of the air outlet passage.

1 . A rack assembly for cooling a computer system, comprising:
 a rack providing support for one or more columns of heat-generating electronic devices and device fans for moving air from an air inlet side of the rack through the devices and through an air outlet side of the rack;   a unitary door having a support frame spanning the air outlet side of the rack and a hinge pivotally coupling the door to a rear vertical edge of the rack, wherein the unitary door includes an air-to-liquid heat exchanger panel spanning an air outlet passage inside the support frame so that substantially all of the air passing through the air outlet side of the rack must pass through the heat exchanger panel; and   a coolant circulation system including a coolant distribution unit for chilling liquid coolant, a supply hose placing the coolant distribution unit in fluid communication with an inlet manifold of the air-to-liquid heat exchanger, and a return hose placing an outlet manifold of the air-to-liquid heat exchanger in fluid communication with the coolant distribution unit, wherein the supply hose and return hose are routed outside the cross-sectional area of the air outlet passage.   
   
   
       2 . The rack assembly of  claim 1 , wherein the one or more columns of heat-generating electronic devices comprise a first set of one or more columns of modular heat-generating electronic devices that each have a minimum power consumption greater than a selected power threshold and a second set of one or more columns of modular heat-generating electronic devices that each have a maximum power consumption less than the selected power threshold. 
   
   
       3 . The rack assembly of  claim 2 , wherein the air outlet passage has a cross-sectional area that is substantially equal to or greater than the combined cross-sectional area of the first set of one or more columns of modular heat-generating electronic devices. 
   
   
       4 . The rack assembly of  claim 1 , further comprising:
 a first hose coupler configured for removably coupling the supply hose to the supply manifold and a second hose coupler configured for removably coupling the return hose to the return manifold, wherein the first and second hose couplers are secured near a lower edge of the rack or the door with a flow axis of each of the first and second hose couplers positioned substantially horizontally and substantially perpendicular to the axis of the hinge.   
   
   
       5 . The rack assembly of  claim 1 , wherein the first and second hose couplers comprise quick-connect type hose couplers. 
   
   
       6 . The rack assembly of  claim 1 , wherein the inlet and outlet manifolds extend along a vertical side of the support frame opposite the hinged coupling. 
   
   
       7 . The rack assembly of  claim 1 , wherein the supply hose is routed from the ceiling to the inlet manifold and the return hose is routed from the outlet manifold to the ceiling. 
   
   
       8 . The rack assembly of  claim 7 , wherein the rack is positioned on a slab floor. 
   
   
       9 . The rack assembly of  claim 7 , wherein the supply hose is coupled to the inlet manifold at the top of the rack and the return hose is coupled to the outlet manifold at the top of the rack. 
   
   
       10 . The rack assembly of  claim 1 , wherein the supply hose is routed through a raised floor to the inlet manifold and the return hose is routed from the outlet manifold through the raised floor. 
   
   
       11 . The rack assembly of  claim 10 , further comprising a cable access opening in the raised floor, wherein the supply hose and return hose are routed from underneath the floor, through the cable access opening, to the air-to-liquid heat exchanger, and a plurality of electronic cables are also routed from underneath the floor, through the cable access opening, to the heat-generating electronic devices supported on the rack. 
   
   
       12 . The rack assembly of  claim 1 , wherein the heat-generating electronic devices comprise a plurality of compute modules each having a motherboard and one or more processors, and wherein the supply hose and return hose are spaced at least twelve inches from any of the compute modules. 
   
   
       13 . The rack assembly of  claim 1 , wherein the supply hose and return hose are routed along a perimeter of the rack underneath a base pan of the rack. 
   
   
       14 . The rack assembly of  claim 1 , wherein the air-to-liquid heat exchanger panel has a capacity that is sufficient to remove all of the heat generated by the electronic devices within the one or more columns of the rack. 
   
   
       15 . The rack assembly of  claim 13 , wherein the supply hose and the return hose are routed underneath the base pan toward the back of the rack. 
   
   
       16 . The rack assembly of  claim 15 , wherein the supply hose and the return hose are free to curve uniformly from the front of the rack to the back of the rack. 
   
   
       17 . The rack assembly of  claim 1 , wherein the one or more columns is at least two columns.