Automated Venting and Refilling of Multiple Liquid Cooling Systems

Abstract

A two-phase liquid cooling system includes an active venting system for regulating an amount of non-condensable gas within the cooling system. Various venting structures may be used to remove gases from the cooling system, some of which are designed to remove the non-condensable gases and avoid removing the vapor-phase coolant. A control system activates the venting system to achieve a desired pressure, which may be based on measured process conditions within the cooling system. A venting and refilling system may serve multiple cooling systems in a parallel arrangement.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

In the course of the detailed description to follow, reference will be made to the attached drawings. These drawings show different aspects of embodiments of the present invention and, where appropriate, reference numerals illustrating like structures, components, and/or elements in different figures are labeled similarly. It is understood that various combinations of the structures, components, and/or elements other than those specifically shown are contemplated and within the scope of the present invention:

FIG. 1 is a schematic diagram of a two-phase liquid cooling system with active venting, in accordance with an embodiment of the invention.

FIG. 2 is a schematic diagram of a rack-mounted spray cooling system, in accordance with an embodiment of the invention.

FIG. 3 is a schematic diagram of a semi-permeable membrane separator, in accordance with an embodiment of the invention.

FIG. 4 is a schematic diagram of a condensing separator, in accordance with an embodiment of the invention.

FIG. 5 is a schematic diagram of a centrifugal separator, in accordance with an embodiment of the invention.

FIG. 6 is a schematic diagram of a permeable tube vacuum mechanism, in accordance with an embodiment of the invention.

FIG. 7 is a chart showing a typical saturation curve for an example cooling liquid.

FIG. 8 is a flow diagram of a control process for activating the active venting system to remove non-condensable gases from the cooling system, in accordance with an embodiment of the invention.

FIG. 9 is a schematic of a venting and refilling system for servicing multiple liquid cooling systems, in accordance with an embodiment of the invention.

FIG. 10 is a chart showing the process conditions during operation of a liquid cooling system, in accordance with an embodiment of the invention.

Claims

1. A centralized system for venting and refilling a plurality of two-phase liquid cooling systems, each cooling system configured to recirculate a coolant through the cooling system and evaporatively cool one or more devices, the servicing system comprising: a venting interface for receiving vented gases from the plurality of cooling systems, the venting interface adjustable to receive vented gases from any one or combination of the cooling systems;a venting system coupled to the venting interface and configurable to exhaust at least some of the received vented gases from the cooling systems;a condenser coupled to the venting system for condensing at least a portion of a condensable coolant in the received vented gases;a reservoir coupled to the condenser to receive the condensed coolant; anda refill interface coupled to the reservoir for providing the condensed coolant to the cooling devices, the refill interface adjustable to provide condensed coolant to any one or combination of the cooling systems.

2. The system of claim 1, wherein the venting interface comprises: a plurality of lines for coupling the venting system to vent ports of the cooling systems in a parallel arrangement; andan adjustable valve in each of the lines to allow or prevent flow of vented gases in each line.

3. The system of claim 2, wherein the adjustable valves are automatically controllable to allow or prevent flow of vented gases in each line.

4. The system of claim 2, wherein the adjustable valves are solenoid valves.

5. The system of claim 1, wherein the venting system comprises: a compressor for pumping gases from the venting interface; andan exhaust valve adjustable to allow or prevent flow of gases out of the venting system.

6. The system of claim 5, wherein the venting system is configured to pump gases from the venting interface until at least a predetermined pressure is reached within one or more of the cooling systems, and then open the exhaust valve to exhaust at least a portion of the gases from the venting system.

7. The system of claim 1, wherein the condenser comprises a condensing column arranged vertically to facilitate separation of vented gases by density.

8. The system of claim 1, wherein the venting system comprises a semi-permeable membrane separator for exhausting at least some of the received vented gases.

9. The system of claim 1, wherein the venting system comprises a condensing separator for exhausting at least some of the received vented gases.

10. The system of claim 1, wherein the venting system comprises a centrifugal separator for exhausting at least some of the received vented gases.

11. The system of claim 1, wherein the venting system comprises a permeable tube vacuum mechanism for exhausting at least some of the received vented gases.

12. The system of claim 1, wherein the reservoir includes a fill interface to receive liquid coolant from an external source.

13. The system of claim 1, wherein the refill interface comprises: a plurality of lines for coupling the reservoir to input ports of the cooling systems in a parallel arrangement; andan adjustable valve in each of the lines to allow or prevent flow of liquid coolant in each line.

14. The system of claim 13, wherein the adjustable valves are solenoid valves.

15. A multi-loop liquid cooling system comprising: a plurality of closed-loop, two-phase liquid cooling systems configured to recirculate a coolant and evaporatively cool one or more devices, each cooling system including an output port for venting gases from the cooling system and an input port for receiving coolant; anda central venting system coupled in a parallel arrangement to the output ports of each of the cooling systems to receive vented gases from the cooling systems, the venting system configured to condense an amount of coolant vapor in the received vented gases and to exhaust an amount of non-condensable gas in the received vented gases.

16. The system of claim 15, wherein each of the cooling systems comprises a plurality of rack-mounted cooling modules thermally coupled to cool a plurality of rack-mounted computing devices.

17. The system of claim 15, wherein the venting system is coupled to each of the cooling systems by a closeable valve, each of the valves independently closeable.

18. The system of claim 15, further comprising: a central reservoir coupled to the venting system to receive the condensed coolant therefrom, the reservoir coupled in a parallel arrangement to the input ports of each of the cooling systems to provide an amount of coolant thereto.

19. The system of claim 18, further comprising: a valve coupled between the central reservoir and each cooling system, each valve adjustable to allow or prevent flow of coolant to the corresponding cooling systems.

20. The system of claim 15, further comprising: a valve coupled between the venting system and each cooling system, each valve adjustable to allow or prevent flow of vented gases from the corresponding cooling systems.

21. The system of claim 15, wherein the venting system comprises: a compressor for pumping vented gases from the cooling systems; andan exhaust valve adjustable to allow or prevent flow of then vented gases out of the venting system.

22. The system of claim 21, wherein the venting system is configured to pump the vented gases from the venting interface until at least a predetermined pressure is reached within the venting system, and then open the exhaust valve to exhaust at least a portion of the vented gases from the venting system.

23. The system of claim 15, wherein the reservoir includes a fill interface to receive liquid coolant from an external source.

24. The system of claim 15, wherein the reservoir is coupled to each of the cooling systems by a closeable valve, each of the valves independently closeable.

25. A centralized system for servicing multiple two-phase liquid cooling systems, the system comprising: a means for selectively receiving an exhaust stream from each of a plurality of two-phase liquid cooling systems; anda means for venting the received exhaust streams.

26. The system of claim 25, further comprising: a reservoir coupled to the means for venting to receive condensed liquid coolant therefrom; anda means for selectively refilling one or more of the cooling systems.

27. A method for venting a non-condensable gas from a plurality of two-phase liquid cooling systems, the method comprising: cooling one or more heat-producing devices by recirculating a coolant through each of a plurality of cooling systems and evaporatively cooling the heat-producing devices therewith;venting gases from at least some of the cooling systems into a central chamber; andexhausting at least a portion of the vented gases from the central chamber.

28. The method of claim 27, wherein each of the cooling systems comprises a plurality of rack-mounted cooling modules thermally coupled to cool a plurality of rack-mounted computing devices.

29. The method of claim 27, further comprising: determining whether to vent each of the cooling systems based at least in part on a process condition within the cooling system;wherein the venting is in response to the determining.

30. The method of claim 29, wherein the process condition is a pressure within the cooling system.

31. The method of claim 27, wherein the venting comprises opening a gas line between the central chamber and each cooling system to be vented, pumping an amount of gas from each corresponding cooling system, and closing each opened gas line.

32. The method of claim 27, wherein the venting comprises pumping gases from at least one cooling system until at least a predetermined pressure is reached within the cooling system.

33. The method of claim 27, further comprising: condensing a portion of the vented gas to reform a liquid coolant in a central reservoir; andrefilling one or more of the cooling systems with the liquid coolant.

34. The method of claim 33, wherein the refilling comprises selectively opening a fluid line from the central reservoir to one or more of the cooling systems.

35. The method of claim 34, wherein the central reservoir is held at a higher pressure than the cooling systems, thereby causing the liquid coolant to flow to the cooling systems.

36. The method of claim 33, adding liquid coolant to the central reservoir from an external source.