US20140124188A1

US20140124188A1 - Liquid cooling system and method for preventing leakage thereof

Info

Publication number: US20140124188A1
Application number: US13/713,287
Authority: US
Inventors: Shuang Xu
Original assignee: Nvidia Corp
Current assignee: Nvidia Corp
Priority date: 2012-11-07
Filing date: 2012-12-13
Publication date: 2014-05-08
Also published as: TW201423016A; CN103813688A; DE102013213837A1

Abstract

The present invention provides a liquid cooling system and a method for preventing leakage thereof. The liquid cooling system comprises: an enclosed cooling liquid circulating assembly with cooling liquid flowing circularly and air above the cooling liquid provided therein; a vacuum pump leading to the air in the enclosed cooling liquid circulating assembly; and a vacuum gauge for measurement of a pressure of the air in the enclosed cooling liquid circulating assembly, wherein the vacuum pump is turned on when the measured pressure is higher than a predetermined pressure, and the vacuum pump is turned off when the measured pressure is not more than the predetermined pressure; wherein the predetermined pressure is set to ensure that the pressure of the cooling liquid is not higher than the atmospheric pressure.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims priority to Chinese Patent Application No. 201210441318.4, filed on Nov. 7, 2012, which is hereby incorporated by reference in its entirety.

FIELD OF INVENTION

The present invention relates generally to the art of cooling system, in particular, to a liquid cooling system and a method for preventing leakage thereof.

BACKGROUND

Liquid cooling system can achieve an effective cooling effect. However, the leakage of the liquid in the liquid cooling system may cause an electrical short circuit in the means being cooled which may cause an entire damage of the whole means being cooled. For an enclosed liquid cooling system (such as the liquid cooling system of the computer room), water and air above the water are contained therein, thus the pressure of the water is greater than the atmospheric pressure outside. So that when there is a crack in the pipeline, liquid may leak from the system to the outside through the crack as a result of the pressure difference between inside and outside, thus an electrical short circuit and even an entire damage of the cooled means might be caused.
Therefore, there is a need of providing a liquid cooling system and a method for preventing leakage thereof to solve the above problem in the prior art.

SUMMARY OF THE INVENTION

In order to solve the above problem, according to one aspect of the present invention, a liquid cooling system is provided which comprises: an enclosed cooling liquid circulating assembly with cooling liquid flowing circularly and air above the cooling liquid provided therein; a vacuum pump leading to the air in the enclosed cooling liquid circulating assembly; and a vacuum gauge for measurement of a pressure of the air in the enclosed cooling liquid circulating assembly, wherein the vacuum pump is turned on when the measured pressure is higher than a predetermined pressure, and the vacuum pump is turned off when the measured pressure is not higher than the predetermined pressure; wherein the predetermined pressure is set to ensure that the pressure of the cooling liquid is not higher than the atmospheric pressure.
Preferably, the predetermined pressure is set to ensure that the highest pressure of the cooling liquid is not higher than the atmospheric pressure.
Preferably, the highest pressure of the cooling liquid is a pressure at the lowest point of the cooling liquid.
Preferably, the liquid cooling system further comprises a controller, wherein an input terminal of the controller is connected to a signal output terminal of the vacuum gauge and a first output terminal of the controller is connected to a controlling terminal of the vacuum pump; and the controller controls a controlling signal of the first output terminal according to an output signal from the signal output terminal so as to control the on/off state of the vacuum pump.
Preferably, the output signal is an analog signal corresponding to the measured pressure.
Preferably, the output signal is an on-off signal which switches depending on whether the measured pressure is higher or not higher than the predetermined pressure.
Preferably, the liquid cooling system further comprises an alarm means connected to a second output terminal of the controller, and when the frequency with which the vacuum pump is turned on is higher than a predetermined frequency, the controller controls the alarm means to raise an alarm via the second output terminal.
Preferably, the predetermined frequency is set to be higher than once per minute.
Preferably, the enclosed cooling liquid circulating assembly comprises: an enclosed cooling liquid circulating passage including a plurality of cooling liquid tubes connected in sequence; a cooling liquid box connected in the enclosed cooling liquid circulating passage and located on the top part of the enclosed cooling liquid circulating assembly; and a cooling liquid pump connected in the enclosed cooling liquid circulating passage, and a cooling liquid inlet of the cooling liquid pump is connected to a cooling liquid outlet of the cooling liquid box.
Preferably, the enclosed cooling liquid circulating assembly further comprises a heat-exchanging device, wherein the heat-exchanging device is connected in the enclosed cooling liquid circulating passage and a cooling liquid inlet of the heat-exchanging device is connected to a cooling liquid outlet of the cooling liquid pump.
Preferably, the enclosed cooling liquid circulating assembly further comprises a radiator, wherein the radiator is connected in the enclosed cooling liquid circulating passage and a cooling liquid inlet of the radiator is connected to a cooling liquid outlet of the heat-exchanging device.
Preferably, an air inlet of the vacuum pump leads to the air and a measurement gauge head of the vacuum gauge is connected to the air inlet of the vacuum pump.
Preferably, the cooling liquid is water.
According to another aspect of the present invention, a method for preventing leakage of a liquid cooling system is also provided which comprises: measuring a pressure of the air above the cooling liquid in the liquid cooling system; judging whether the measured pressure is higher than a predetermined pressure, and when the measured pressure is higher than the predetermined pressure, vacuumizing the liquid cooling system until the pressure of the air is not higher than the predetermined pressure, wherein the predetermined pressure is set to ensure that the pressure of the cooling liquid is not higher than the atmospheric pressure.
Preferably, the predetermined pressure is set to ensure that the highest pressure of the cooling liquid is not higher than the atmospheric pressure.
Preferably, the highest pressure of the cooling liquid is a pressure at the lowest point of the cooling liquid.
Preferably, an alarm is raised when the frequency with which the vacuumizing is performed is higher than a predetermined frequency.
Preferably, the predetermined frequency is set to be higher than once per minute.
Following are the effectiveness of the present invention:
In the liquid cooling system of the invention, the vacuum pump is leading to the air in the enclosed cooling liquid circulating assembly and the vacuum gauge can measure the pressure of the air in the enclosed cooling liquid circulating assembly. The vacuum pump is turned on when the measured pressure is higher than a predetermined pressure, and the vacuum pump is turned off when the measured pressure is not higher than the predetermined pressure. In other words, the cooperation between the vacuum pump and the measurement of the vacuum gauge enables the pressure of the air in the cooling liquid circulating assembly to be always lower than the predetermined pressure. The predetermined pressure is set to ensure that the pressure of the cooling liquid is not higher than the atmospheric pressure, i.e. the predetermined pressure is set to such a value that as long as the pressure of the air in the cooling liquid circulating assembly is not higher than the predetermined pressure through vacuumizing of the liquid cooling system, the pressure of the cooling liquid (i.e. the pressure generated by the cooling liquid itself plus the pressure of the air in the cooling liquid circulating assembly) is not higher than the atmospheric pressure.
Thus, since the pressure of the cooling liquid is not higher than the atmospheric pressure, only the air outside may enter into the liquid cooling system while the cooling liquid can't leak outside even if there is a crack in the liquid cooling system. Therefore, the liquid cooling system of the present invention prevents the cooling liquid in the system from leaking outside, thus prevents the electrical short circuit and the entire damage of the means being cooled.
Similarly, in the method for preventing leakage of the liquid cooling system of the present invention, by measuring the pressure of the air above the cooling liquid in the liquid cooling system, judging whether the measured pressure is higher than the predetermined pressure (wherein the predetermined pressure is set to ensure that the pressure of the cooling liquid is not higher than the atmospheric pressure), and vacuumizing the liquid cooling system according to the result of the judging, it is enabled that the pressure of the cooling liquid is not higher than the atmospheric pressure. In this way, the method prevents the cooling liquid in the system from leaking outside, and thus prevents the electrical short circuit and the entire damage of the means being cooled.
A serial of simplified conceptions are incorporated into the summary of the invention, which will be further described in more detail in the detailed description. The summary of the invention neither implies that it is intended to limit the essential features and necessary technical features of the technical solution to be protected, nor implies that it is intended to define the protection scope of the technical solution to be protected.
Advantages and features of the present invention will be described in detail below in connection with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

The following drawings of the present invention as a part of the present invention herein are used for understanding of the present invention, the embodiments and the descriptions thereof are illustrated in the drawings for explaining the principle of the present invention. In the drawings,

FIG. 1 illustrates the schematic diagram of the liquid cooling system according to the embodiment of the invention;

FIG. 2 illustrates the schematic block diagram of the connection relationship between the controller and the other components of the liquid cooling system according to the embodiment of the invention;

FIG. 3 illustrates the schematic flow diagram of a method for preventing leakage of the liquid cooling system according to the embodiment of the invention.

DETAILED DESCRIPTION

A plenty of specific details are presented so as to provide more thoroughly understanding of the present invention in the description below. However, the present invention may be implemented without one or more of these details, as is obvious to those skilled in the art. In other examples, some of the technical features known in the art are not described so as to avoid confusions with the present invention.
As shown in FIG. 1, a liquid cooling system according to the embodiment of the invention comprises an enclosed cooling liquid circulating assembly 1, a vacuum pump 2 and a vacuum gauge 3. There are cooling liquid 11 flowing circularly and air 12 above the cooling liquid 11 in the enclosed cooling liquid circulating assembly 1, as shown in FIG. 1. The vacuum pump 2 leads to the air 12 in the enclosed cooling liquid circulating assembly 1. The vacuum gauge 3 is used for measuring a pressure of the air 12 in the enclosed cooling liquid circulating assembly 1. Wherein the vacuum pump 2 is turned on when the pressure measured by the vacuum gauge 3 is higher than a predetermined pressure, and the vacuum pump 2 is turned off when the pressure measured by the vacuum gauge 3 is not higher than the predetermined pressure.
The abovementioned predetermined pressure is set to ensure that the pressure of the cooling liquid 11 is not higher than the atmospheric pressure, i.e. the predetermined pressure is set to such a value that as long as the pressure of the air 12 in the cooling liquid circulating assembly 1 is not higher than the predetermined pressure through vacuumizing of the liquid cooling system, the pressure of the cooling liquid (i.e. the pressure generated by the cooling liquid 11 itself plus the pressure of the air 12 in the cooling liquid circulating assembly 1) is not higher than the atmospheric pressure.
Thus, since the pressure of the cooling liquid 11 is not higher than the atmospheric pressure, only the air outside may enter into the liquid cooling system while the cooling liquid 11 can't leak outside even if there is a crack in the liquid cooling system. Therefore, the liquid cooling system of the present invention prevents the cooling liquid in the system from leaking outside, thus prevents the electrical short circuit and the entire damage of the means being cooled.
Preferably, the predetermined pressure may be set to ensure that the highest pressure of the cooling liquid 11 is not higher than the atmospheric pressure. In other words, the pressure at the position where the pressure is highest in the cooling liquid 11 is not higher than the atmospheric pressure, so that the cooling liquid 11 does not leak outside at any position in the system.
More preferably, the highest pressure of the cooling liquid 11 is the pressure at the lowest point of the cooling liquid. The liquid cooling system of the present embodiment is a liquid cooling system used for the computer room, the cooling liquid 11 therein is retained below the air therein with the highest pressure thereof being the pressure at the lowest point of the cooling liquid 11. Therefore, it will be guaranteed that the cooling liquid 11 does not leak outside at any position of the system as long as it is ensured that the pressure at the lowest point of the cooling liquid 11 is not higher than the atmospheric pressure. For example, assume that the depth of the liquid in the present embodiment is 1 meter, then the highest pressure therein, i.e. the pressure at the lowest point of the cooling liquid 11 is the sum of the pressure of the 1 meter of water column and the pressure of the air 12 above the cooling liquid 11. Because the atmospheric pressure is approximately equal to the pressure of the 10 meters of water column, the sum of the pressure of the 1 meter of water column and the pressure of the air 12 above the cooling liquid 11 should be not higher than the pressure of 10 meters of water column, in other words, the pressure of the air 12 above the cooling liquid 11 should be not higher than the pressure of the 9 (10−1) meters of water column. Consequently, the predetermined pressure can be set to be the pressure of 9 meters of water column or less than the pressure of the 9 meters of water column.
The vacuum pump 2 can be manually controlled to be turned on and off according to the indication of the vacuum gauge 3. However, preferably, as shown in FIG. 2, the liquid cooling system further comprises a controller 4, wherein an input terminal 41 of the controller 4 is connected to a signal output terminal 31 of the vacuum gauge 3, and a first output terminal 42 of the controller 4 is connected to a controlling terminal 21 of the vacuum pump 2 (for the sake of brevity, the GND wire, etc. are removed in FIG. 2). The controller 4 controls a controlling signal of the first output terminal 42 according to an output signal from the signal output terminal 31 so as to control the on/off state of the vacuum pump 2. Thus, it is achieved that the on/off state of the vacuum pump 2 can be controlled automatically according to the measured value from the vacuum gauge 3, and it is ensured automatically that the pressure of the cooling liquid 11 is not higher than the atmospheric pressure. In the embodiment, the controller 4 is a PLC. However, in practice, the controller 4 can be any suitable controlling means according to actual requirements, such as a hardware circuit, etc.
The vacuum gauge 3 outputs the output signal corresponding to the measured pressure to the controller 4 via the abovementioned signal output terminal 31. Preferably, the output signal is an analog signal corresponding to the measured pressure. The controller 4 determines whether the measured pressure is higher than the predetermined pressure according to the analog signal. Or preferably, the output signal is an on-off signal which switches depending on whether the measured pressure is higher/not higher than the predetermined pressure. The controller 4 determines whether the measured pressure is higher than the predetermined pressure according to the value of the on-off signal.
In addition, it can be seen from the content mentioned above that the vacuum bump 2 does not need to run all the time. In the case that the pressure of the cooling liquid 11 in the liquid cooling system is kept being lower than the atmospheric pressure, the pressure difference between inside and outside of the system can be maintained for a certain period, during which there is no need to turn the vacuum pump 2 on. The vacuum pump 2 is turned on only when the pressure measured by the vacuum gauge 3 is higher than the predetermined pressure. It can be understood that if the vacuum pump is turned on too frequently, it means that the system might be severely leaking. Consequently, preferably, the liquid cooling system further comprises an alarm means 5 which is connected to a second output terminal 43 of the controller 4, as shown in FIG. 2. When the frequency with which the vacuum pump 2 is turned on is higher than a predetermined frequency, the controller 4 controls the alarm means 5 to raise an alarm via the second output terminal 43 so as to inform the users that the liquid cooling system may have leaked severely.
The predetermined frequency may be set to a suitable value according to the specific condition of the system. Preferably, the predetermined frequency is set to be higher than once per minute, such as three times per minute, i.e. the system raises an alarm if the vacuum pump is turned on more than three times per minute.
In addition, the enclosed cooling liquid circulating assembly 1 can have any suitable structure in which the liquid cooling 11 can circulate. Preferably, as shown in FIG. 1, the enclosed cooling liquid circulating assembly 1 of the present embodiment comprises an enclosed cooling liquid circulating passage 13, a cooling liquid box 14 and a cooling liquid pump 15. The enclosed cooling liquid circulating passage 13 includes multiple of cooling liquid tubes connected in sequence. The cooling liquid box 14 is connected in the enclosed cooling liquid circulating passage 13 and located on the top part of the enclosed cooling liquid circulating assembly 1, thus the abovementioned air 12 is located at the upper part of the cooling liquid box 14. The cooling liquid pump 15 is connected in the enclosed cooling liquid circulating passage 13, and a cooling liquid inlet of the cooling liquid pump 15 is connected to a cooling liquid outlet of the cooling liquid box. Thus, the cooling liquid 11 in the cooling liquid box 14 is pumped into the cooling liquid circulating passage 13 through the cooling liquid pump 15 and flows back to the cooling liquid inlet of the cooling liquid box through the cooling liquid circulating passage 13.
More preferably, as shown in FIG. 1, the enclosed cooling liquid circulating assembly 1 of the embodiment further comprises a heat-exchanging device 16 which is connected in the enclosed cooling liquid circulating passage 13. A cooling liquid inlet of the heat-exchanging device 16 is connected to a cooling liquid outlet of the cooling liquid pump 14, thus the cooling liquid 11 flows through the interior of the heat-exchanging device 16. The heat-exchanging device 16 contacts the means being cooled (such as a server, not shown in the figures), and acts to cool the means by the cooling liquid 11 flowing through the interior thereof.
The heat-exchanging device 16 contacts the means being cooled, and the temperature of the cooling liquid 11 flowing out from the interior of the heat-exchanging device 16 increases. So, more preferably, as shown in FIG. 1, the enclosed cooling liquid circulating assembly 1 further comprises a radiator 17 which is connected in the enclosed cooling liquid circulating passage 13. A cooling liquid inlet of the radiator 17 is connected to a cooling liquid outlet of the heat-exchanging device 16, thus the cooling liquid 11 with higher temperature flowing out from the heat-exchanging device 16 flows through the interior of the radiator 17, and drops back to a lower temperature through the heat dissipation of the radiator 17.
In addition, preferably, in the present embodiment, an air inlet of the vacuum pump 2 leads to the air 12 so as to vacuumize the liquid cooling system. A measurement gauge head of the vacuum gauge 3 is connected to the air inlet of the vacuum pump 2 so as to measure the vacuum degree of the air 12.
In addition, the abovementioned cooling liquid 11 can be any suitable liquid. Preferably, the cooling liquid is water in the present embodiment.
As shown in FIG. 3, a method for preventing leakage of a liquid cooling system according to the embodiment of the invention comprises the following steps:
S101: measuring a pressure of the air above the cooling liquid in the liquid cooling system.
S102: judging whether the measured pressure is higher than a predetermined pressure.
When the measured pressure is higher than the predetermined pressure, turn to step S103: vacuumizing the liquid cooling system until the pressure of the air is not higher than the predetermined pressure.
The predetermined pressure is set to ensure that the pressure of the cooling liquid is not higher than the atmospheric pressure. The predetermined pressure is same to the predetermined pressure as mentioned above in the description of the liquid cooling system and will not be described in detail here. It can be understood that by measuring of the pressure of the air above the cooling liquid in the liquid cooling system in step S101, and by judging whether the measured pressure is higher than the predetermined pressure in step S102 and vacuumizing the liquid cooling system according to the result of the judging, it is enabled that the pressure of the cooling liquid is not higher than the atmospheric pressure. In this way, the method prevents the cooling liquid in the system from leaking outside, and thus prevents the electrical short circuit and the entire damage of the means being cooled.
Preferably, the predetermined pressure may be set to ensure that the highest pressure of the cooling liquid is not higher than the atmospheric pressure. In other words, the pressure at the position where the pressure is highest in the cooling liquid is not higher than the atmospheric pressure, so that the cooling liquid dose not leak outside at any position in the system.
More preferably, the highest pressure of the cooling liquid is a pressure at the lowest point of the cooling liquid.
In addition, preferably, the method for preventing leakage of the liquid cooling system according to the embodiment of the invention further comprises raising an alarm when the frequency of the vacuumizing is higher than the predetermined frequency so as to inform the users that the liquid cooling system may have leaked severely. The predetermined frequency may be set to a suitable value according to the specific condition of the system. Preferably, the predetermined frequency is set to be higher than once per minute, such as three times per minute, i.e. the system raises an alarm if the vacuum pump is turned on more than three times per minute.
The present invention has been described by the above-mentioned embodiments. However, it will be understand that the above-mentioned embodiments are for the purpose of demonstration and description and not for the purpose of limiting the present to the scope of the described embodiments. Moreover, those skilled in the art could appreciated that the present invention is not limited to the above mentioned embodiments and that various modifications and adaptations in accordance of the teaching of the present invention may be made within the scope and spirit of the present invention. The protection scope of the present invention is further defined by the following claims and equivalent scope thereof.

Claims

What is claimed is:

1. A liquid cooling system, comprising:

an enclosed cooling liquid circulating assembly with cooling liquid flowing circularly and air above the cooling liquid provided therein;

a vacuum pump leading to the air in the enclosed cooling liquid circulating assembly; and

a vacuum gauge for measurement of a pressure of the air in the enclosed cooling liquid circulating assembly,

wherein the vacuum pump is turned on when the measured pressure is higher than a predetermined pressure, and the vacuum pump is turned off when the measured pressure is not higher than the predetermined pressure;

wherein the predetermined pressure is set to ensure that the pressure of the cooling liquid is not higher than an atmospheric pressure.

2. The liquid cooling system according to claim 1, wherein the predetermined pressure is set to ensure that a highest pressure of the cooling liquid is not higher than the atmospheric pressure.

3. The liquid cooling system according to claim 2, wherein the highest pressure of the cooling liquid is a pressure at a lowest point of the cooling liquid.

4. The liquid cooling system according to claim 1, wherein the liquid cooling system further comprises a controller, wherein:

an input terminal of the controller is connected to a signal output terminal of the vacuum gauge and a first output terminal of the controller is connected to a controlling terminal of the vacuum pump; and

the controller controls a controlling signal of the first output terminal according to an output signal from the signal output terminal so as to control the turning on and the turning off of the vacuum pump.

5. The liquid cooling system according to claim 4, wherein the output signal is an analog signal corresponding to the measured pressure.

6. The liquid cooling system according to claim 4, wherein the output signal is an on-off signal which switches depending on whether the measured pressure is higher or not higher than the predetermined pressure.

7. The liquid cooling system according to claim 4, wherein the liquid cooling system further comprises an alarm device connected to a second output terminal of the controller, and when a frequency with which the vacuum pump is turned on is higher than a predetermined frequency, the controller controls the alarm device to raise an alarm via the second output terminal.

8. The liquid cooling system according to claim 7, wherein the predetermined frequency is set to be higher than once per minute.

9. The liquid cooling system according to claim 1, wherein the enclosed cooling liquid circulating assembly comprises:

an enclosed cooling liquid circulating passage including a plurality of cooling liquid tubes connected in sequence;

a cooling liquid box connected in the enclosed cooling liquid circulating passage and located on a top part of the enclosed cooling liquid circulating assembly; and

a cooling liquid pump connected in the enclosed cooling liquid circulating passage, wherein a cooling liquid inlet of the cooling liquid pump is connected to a cooling liquid outlet of the cooling liquid box.

10. The liquid cooling system according to claim 9, wherein the enclosed cooling liquid circulating assembly further comprises a heat-exchanging device, wherein

the heat-exchanging device is connected in the enclosed cooling liquid circulating passage and a cooling liquid inlet of the heat-exchanging device is connected to a cooling liquid outlet of the cooling liquid pump.

11. The liquid cooling system according to claim 10, wherein the enclosed cooling liquid circulating assembly further comprises a radiator, wherein

the radiator is connected in the enclosed cooling liquid circulating passage and a cooling liquid inlet of the radiator is connected to a cooling liquid outlet of the heat-exchanging device.

12. The liquid cooling system according to claim 1, wherein an air inlet of the vacuum pump leads to the air and a measurement gauge head of the vacuum gauge is connected to the air inlet of the vacuum pump.

13. The liquid cooling system according to claim 1, wherein the cooling liquid is water.

14. A method for preventing leakage of a liquid cooling system, comprising:

measuring a pressure of air above a cooling liquid in a liquid cooling system;

judging whether the measured pressure is higher than a predetermined pressure, and when the measured pressure is higher than the predetermined pressure, vacuumizing the liquid cooling system until the pressure of the air is not higher than the predetermined pressure,

15. The method according to claim 14, wherein the predetermined pressure is set to ensure that a highest pressure of the cooling liquid is not higher than the atmospheric pressure.

16. The method according to claim 14, wherein the highest pressure of the cooling liquid is a pressure at a lowest point of the cooling liquid.

17. The method according to claim 14, wherein an alarm is raised when a frequency with which the vacuumizing is performed is higher than a predetermined frequency.

18. The method according to claim 17, wherein the predetermined frequency is set to be higher than once per minute.