Liquid submerged, horizontal computer server rack and systems and method of cooling such a server rack

Abstract

An apparatus for cooling a plurality of rack-mountable servers containing heat generating electronic components in a server room including a dielectric liquid cooling apparatus located inside the tank and a secondary cooling apparatus comprising a remote heat exchanger and at least one pump. The volume of dielectric liquid coolant comprises at least one passage in the tank that is outside of the vertically oriented rack-mountable servers. When the at least one pump is operated to move the dielectric liquid coolant vertically across the heat producing components on the vertically oriented servers, a circuit is formed in which a first portion of dielectric liquid coolant is moved vertically upward across the heat producing components on the vertically oriented servers and then downward outside of the rack mountable servers in the at least one passage, while a second portion of the dielectric liquid coolant flows out of the tank.

1 . A system comprising:
 a tank having a closed tank bottom and tank sidewalls coupled to the tank bottom, the tank including: (1) a pool of dielectric liquid directly contacting the tank bottom and tank sidewalls while being retained within the tank by the tank bottom and tank sidewalls, (2) a rack, and (3) independently operable and non-hermitically sealed servers that are coupled to the rack and submerged at least half way in the of pool of dielectric liquid;   an air radiator, located entirely outside the tank, including a channel to include the dielectric liquid;   a tank inlet and a tank outlet;   at least one pump, located entirely outside the tank, to pump the dielectric liquid ( 1 ) from the tank, through the tank outlet, and then to the channel of the air radiator, and (2) from the channel of the air radiator, through the tank inlet, and the back into the tank;   wherein each of the servers includes at least one printed circuit board in direct contact with the dielectric liquid and within a server chassis, the server chassis including both: (1) a front panel, a rear panel, and at least one side panel, and (2) at least one vent to allow the dielectric liquid to flow into the server chassis through one of the front or rear panels and then out of the server chassis through another of the front or rear panels;   wherein the tank, the rack, and the multiple server chassis are coupled to each other to provide at least one liquid passage in the tank and outside of the multiple server chassis, the at least one liquid passage including a lower space between the multiple server chassis and the tank bottom and an additional space outside of the multiple server chassis;   wherein the at least one liquid passage defines a circuit for flow of the dielectric liquid extending from the tank inlet, and then across the lower space beneath the multiple server chassis, and then vertically upwards and simultaneously, via parallel liquid flow, through the multiple server chassis followed by exiting the multiple server chassis, and then horizontally towards the tank outlet;   wherein: (1) a horizontal axis, parallel to the tank bottom, intersects two of the tank sidewalls, at least two of the multiple server chassis, and the additional space, and (2) a vertical axis, orthogonal to the horizontal axis, intersects the front and bottom panels of at least one of the multiple server chassis, the tank bottom, and the lower space;   wherein the tank is arranged to enable removal of any one of the multiple chassis through a top of the tank: (1) without removal of any other server chassis from the tank and without disconnecting communication and power cords of any other server chassis, and (2) while allowing other servers contained in other server chassis to continue to be submerged at least half way in the pool of dielectric fluid, cooled, and operating;   wherein the tank is arranged to allow the communication and power cords to pass through the top of the tank.   
     
     
         2 . The system of  claim 1  comprising a bracket that couples at least one of the multiple server chassis to the rack. 
     
     
         3 . The system of  claim 1  comprising at least one controller and at least one sensor, wherein the at least one controller is configured to, in response to the sensor sensing a temperature of the dielectric liquid, adjust a flow rate of the dielectric liquid to regulate the temperature of the dielectric liquid. 
     
     
         4 . The system of  claim 1  comprising at least one controller and at least one sensor, wherein the at least one controller is configured to, in response to the sensor sensing a temperature of the dielectric liquid, modify a flow rate of the dielectric liquid to maintain the temperature of the dielectric liquid above a previously determined temperature setting. 
     
     
         5 . The system of  claim 1 , wherein:
 the dielectric liquid is a nonflammable oil with a dielectric strength better than a dielectric strength of air;   each of the servers is a rack mountable computing device configured to connect to a computing network and run software configured to receive requests from computing devices;   each of the servers is configured to function without regard to an operational status of an adjacent server.   
     
     
         6 . The system of  claim 1 , wherein the additional space directly contacts at least one of tank sidewalls. 
     
     
         7 . The system of  claim 1 , wherein:
 the tank is included inside a building and the air radiator is located outside the building;   the air radiator is configured to transfer heat from the dielectric liquid to air outside of the building.   
     
     
         8 . The system of  claim 7 , wherein the rack mounts the multiple server chassis above the tank bottom so none of the front, rear, or side panels of the multiple server chassis directly contact the tank bottom. 
     
     
         9 . The system of  claim 7 , wherein
 each of the multiple server chassis include projections to couple to the rack;   an additional vertical axis, orthogonal to the horizontal axis, intersects one of the projections but does not intersect any front or bottom panels of any server chassis.   
     
     
         10 . The system of  claim 7 , wherein the tank is statically fixed within the building. 
     
     
         11 . The system of  claim 7 , wherein the at least one liquid passage defines the circuit for flow of the dielectric liquid extending from the tank inlet, and then across the lower space beneath the multiple server chassis, and then vertically upwards and simultaneously, via parallel liquid flow, through the multiple server chassis followed by exiting the multiple server chassis into a common manifold area above the multiple server chassis, and then horizontally towards the tank outlet. 
     
     
         12 . The system of  claim 1 , wherein the tank includes:
 an additional rack; and   additional independently operable and non-hermitically sealed servers that are coupled to the additional rack and submerged at least half way in the pool of dielectric liquid;   wherein each of the additional servers includes at least one additional printed circuit board in direct contact with the dielectric liquid and within an additional server chassis, the additional server chassis including both: (1) an additional front panel, an additional rear panel, and at least one additional side panel, and (2) at least one additional vent to allow the dielectric liquid to flow into the additional server chassis through one of the additional front or rear panels and then out of the additional server chassis through another of the additional front or rear panels;   wherein a plane, orthogonal to the vertical axis, intersects the multiple server chassis and the additional multiple server chassis;   wherein: (1) the tank, the rack, the additional rack, the multiple server chassis, and additional multiple server chassis are arranged with respect to one another to define at least one additional liquid passage in the tank and outside of the additional multiple server chassis, the at least one additional liquid passage including the lower space and an intermediate space between the rack and the additional rack, (2) the at least one additional liquid passage defines an additional circuit for flow of the dielectric liquid across the lower space and then vertically upwards across the multiple server chassis and the additional multiple server chassis and then downwards across the intermediate space back towards the tank bottom.   
     
     
         13 . The system of  claim 1 , wherein the rack mounts the multiple server chassis with spacing between two adjacent server chassis that is configured to restrict the flow of the dielectric liquid through the spacing and, in response, promote flow of the dielectric liquid through the server chassis of the two adjacent servers. 
     
     
         14 . The system of  claim 1  comprising:
 a cable tray coupled to the tank to organize the communication cords; and 
 a power distribution unit to distribute power to the power cords. 
 
     
     
         15 . The system of  claim 1 , wherein:
 the tank outlet includes an outlet conduit that interfaces at least one of the tank bottom, tank sidewalls, or combinations thereof at a first location;   the tank inlet includes an inlet conduit that interfaces the at least one of the tank bottom, tank sidewalls, or combinations thereof at a second location;   a top surface of the pool of dielectric fluid interfaces the tank sidewalls at a third location;   the third location is above the first and second locations;   the third location is between the top of the tank and the first location;   the third location is between the top of the tank and the second location.   
     
     
         16 . The system of  claim 1 , wherein:
 the rack holds the multiple server chassis such that at least one of the multiple server chassis is independently removable, through the top of the tank, from the dielectric liquid while at least two other server chassis held in the rack remain submerged at least half way in the pool of dielectric liquid;   any one or more of the multiple server chassis can be removed while at least one other of the servers in another server chassis remains operating.   
     
     
         17 . The system of  claim 1 , wherein the circuit for flow of the dielectric liquid extends through the additional space.