CN111669952A - A data center immersion cooling device - Google Patents

Abstract

The invention relates to an immersed heat dissipation device for a data center, comprising a liquid cooling cabinet, a cooling liquid, and a plurality of oscillating heat pipes. The cooling liquid is filled in the liquid cooling cabinet, and the evaporation areas of the plurality of oscillating heat pipes extend into the liquid cooling cabinet. The oscillating heat pipe is filled with a medium, which is an organic solvent, and the connection area between the oscillating heat pipe and the side wall of the liquid cooling cabinet is an adiabatic area, and the adiabatic area is located between the condensation area and the evaporation area. The heat from the oscillating heat pipe into the coolant is transferred to the outside of the liquid-cooled cabinet. The heating element transfers heat to the cooling liquid, the evaporation area of the heat pipe bundle is immersed in the cooling liquid, and absorbs the heat of the cooling liquid. The organic solvent with a certain pressure is poured into the heat pipe bundle as a medium, and the medium evaporates after being heated, forming gas in the heat pipe bundle. A plunger-type fluid between liquid phases, the plunger-type fluid rapidly transfers heat to the condensation area of the heat pipe bundle. High heat transfer coefficient, low energy consumption, energy saving and environmental protection.

Description

A data center immersion cooling device

technical field

The invention belongs to the technical field of liquid cooling, and in particular relates to an immersed heat dissipation device for a data center.

Background technique

The information disclosed in this Background section is only for enhancement of understanding of the general background of the invention and should not necessarily be taken as an acknowledgement or any form of suggestion that this information forms the prior art already known to a person of ordinary skill in the art.

With the continuous development of the Internet and computer technology, the construction of data centers in the era of big data is also developing rapidly. The rapid development of big data has brought both opportunities and new challenges to the development of computers. As the global data processing demand continues to heat up, high energy consumption indicators also bring new challenges to the rapid development of data centers. According to a research report by Global Market Insights (GMI), data centers currently use about 3% of the world's total electricity consumption, and this number is expected to rise to 8% by 2030. As cooling system energy consumption accounts for approximately 40% of the total energy consumption of data centers, the demand for intelligent energy-saving solutions is expected to drive the continuous growth of the data center cooling market.

Christian Belady proposed the concept of data center energy utilization (PUE) in 2006. The value of PUE of a data center is equal to the ratio of the total energy consumption of the data center to the energy consumption of IT equipment. The smaller the ratio, the higher the energy utilization rate of the data center. , the more the data center meets the low-carbon and energy-saving standards. At present, the value of some small-scale domestic enterprises may be as high as about 3. Compared with international IT companies, Yahoo data center (PUE=1.08), Facebook data center (PUE=1.15), Google Belgium data center (PUE=1.16), Hewlett-Packard UK Wenzhou Yed data center (PUE=1.16), Microsoft Dublin data center (PUE=1.25), Microsoft Ireland Dublin data center, using innovatively designed "free cooling" system and hot aisle control, its PUE value is much lower than other Microsoft data 1.6 of the center. The average PUE value of all self-developed data centers of Alibaba, which is a leading domestic technology company, is already lower than 1.3. In 2018, the measured annual PUE value of Tencent Shenzhen Guangming Data Center was 1.26, which is still far behind the international advanced enterprises. .

The traditional data center cooling system uses precision air conditioners (that is, air cooling technology) to cool the rooms where the cabinets are located. Since the data center generates a large amount of heat and requires basic constant temperature and humidity to operate continuously, the air conditioning system that can be used for its use requires reliability. High (generally designed with redundant backup machines), large cooling capacity, small temperature difference and large air volume, the air conditioning system of the data center has its remarkable particularity. First, it runs uninterrupted throughout the year, and the working conditions vary greatly; second It is the high precision of temperature and humidity control, dehumidification, humidification, heating, small temperature difference and large air volume, etc., which consume more additional energy than ordinary civil air conditioning systems. Area. The IT equipment in the high temperature area cannot work normally or even stops working, and the high temperature environment will shorten the service life of the equipment and cause immeasurable economic losses. However, due to the lower cost and simpler installation and deployment of air cooling technology, it is still the mainstream cooling technology in the current data center field.

In recent years, with the sharp increase in the heat flow density of data centers, liquid cooling technology has gradually become one of the key technologies to solve the future heat dissipation problems of data centers due to its outstanding cooling effect and low energy consumption. Among them, the cooling liquid, such as fluorinated liquid, can be in direct contact with IT equipment. This immersion cooling technology has good heat dissipation effect and obvious energy saving advantages. This technology helps to further improve the data density and computing power of the server. However, the existing cooling technology still has problems related to uneven temperature distribution and high energy consumption. The immersed liquid-cooled server cooling system disclosed in the prior art includes a server chassis, a box cover, a heat dissipation group, a radiator, and an oil collecting tank. and oil pump. The system has high heat transfer efficiency, realizes the effect of energy saving and environmental protection, can effectively target the local flow cooling of heating elements such as chips, and is easy to uniformize the temperature, which is conducive to more effective heat dissipation of the heating chip. The disadvantage is that the oil pump is noisy during operation and increases energy consumption. Its vibration is also a hidden danger for the safe and stable operation of the system. The choice of radiator and refrigerant also increases the cost.

Both direct cooling and immersion cooling systems have the disadvantages of higher cost, larger vibration or noise, and the layout is limited by the space in the computer room.

SUMMARY OF THE INVENTION

In view of the above problems in the prior art, the purpose of the present invention is to provide an immersion cooling system for a data center.

In order to solve the above technical problems, the technical scheme of the present invention is:

In the first aspect, an immersed heat dissipation device for a data center includes a liquid cooling cabinet, a cooling liquid, and a plurality of oscillating heat pipes. The cooling liquid is filled in the liquid cooling cabinet, and the evaporation areas of the plurality of oscillating heat pipes extend into the liquid cooling cabinet. The condensation area is located on the outside of the liquid cooling cabinet. The tube bundle of the oscillating heat pipe is filled with a medium, and the medium is an organic solvent. The connection area between the oscillating heat pipe and the side wall of the liquid cooling cabinet is an adiabatic area.

The invention utilizes oscillating heat pipes to dissipate heat from the liquid cooling cabinet. Make full use of the heat dissipation characteristics of the oscillating heat pipe to make the heat dissipation effect of the liquid cooling cabinet better, and no external power is required. Low vibration and noise. The installation form of the oscillating heat pipe is more flexible, and it is not limited by the space of the computer room.

In the state where the tube is evacuated, a certain amount of organic solvent is poured as the medium, and the liquid does not fill the inner cavity of the entire oscillating heat pipe bundle. Under the action of the temperature difference between the hot and cold ends and the surface tension, the medium forms a plunger-type fluid between the gas and liquid phases, which randomly appears in the pipeline.

The heat generated in the liquid cooling cabinet is transferred to the oscillating heat pipe through the cooling liquid. In the evaporation area of the oscillating heat pipe, the organic solvent is heated and evaporated, and then a plunger fluid between the gas and liquid phases is formed in the tube bundle of the oscillating heat pipe. The liquid film between the tube walls is continuously evaporated due to heating, which causes the bubbles to expand, and pushes the gas-liquid plunger to flow to the condensation area to condense and shrink, thereby forming a large pressure difference between the cold and hot ends. Due to the staggered distribution of the gas-liquid plungers, a strong reciprocating oscillating motion is generated in the tube, thereby achieving efficient heat transfer. The condensing area of the oscillating heat pipe dissipates heat, and the heat in the condensing area can be taken away by the cooling effect of natural wind. The entire heat transfer process does not require external mechanical and electrical work, and does not require energy-consuming equipment such as fans and pumps.

The second aspect is the application of the above-mentioned data center immersion cooling device in the data center immersion cooling.

Beneficial effects of the present invention:

(1) The cooling liquid is in direct contact with the heating equipment, has low convection thermal resistance, high heat transfer coefficient, uniform heat dissipation, and can quickly take away heat, with good heat dissipation effect;

(2) The oscillating heat pipe has small thermal resistance, excellent heat transfer performance, and simple mechanism, which can be flexibly arranged, not affected by direction, can be bent arbitrarily, and is not affected by the space of the machine room, and the medium in the heat pipe is an organic solvent, and the working start-up temperature is low. It can ensure that the coolant temperature is kept low;

(3) The heat transfer process of the whole system does not need to consume external mechanical work and electrical work, and belongs to the self-excited oscillation heat transfer driven by heat. It can effectively reduce the energy consumption of the system, save energy and protect the environment.

Description of drawings

The accompanying drawings forming a part of the present invention are used to provide further understanding of the present application, and the exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention.

1 is a structural diagram of a data center immersion cooling device of the present invention;

Fig. 2 is the front view of the oscillating heat pipe of the present invention;

3 is a side view of the oscillating heat pipe of the present invention;

4 is a side view of the oscillating heat pipe of the present invention;

Among them, 1. Computer room, 2. First liquid-cooled cabinet, 3. Second liquid-cooled cabinet, 4. Third liquid-cooled cabinet, 5. Server, 6. Oscillating heat pipe, 7. Condensing area, 8. Adiabatic area, 9 , evaporation zone.

Detailed ways

It should be noted that the following detailed description is exemplary and intended to provide further explanation of the invention. Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs.

It should be noted that the terminology used herein is for the purpose of describing specific embodiments only, and is not intended to limit the exemplary embodiments according to the present application. As used herein, unless the context clearly dictates otherwise, the singular is intended to include the plural as well, furthermore, it is to be understood that when the terms "comprising" and/or "including" are used in this specification, it indicates that There are features, steps, operations, devices, components, and/or combinations thereof.

In the first aspect, an immersed heat dissipation device for a data center includes a liquid cooling cabinet, a cooling liquid, and a plurality of oscillating heat pipes. The cooling liquid is filled in the liquid cooling cabinet, and the evaporation areas of the plurality of oscillating heat pipes extend into the liquid cooling cabinet. The condensation area is located on the outside of the liquid cooling cabinet. The tube bundle of the oscillating heat pipe is filled with a medium, and the medium is an organic solvent. The connection area between the oscillating heat pipe and the side wall of the liquid cooling cabinet is an adiabatic area.

The heat from the oscillating heat pipe into the coolant is transferred to the outside of the liquid-cooled cabinet. The interior of the liquid cooling cabinet is a heating component due to the servers and other equipment. The heating element transfers heat to the cooling liquid. The evaporation area of the heat pipe bundle is immersed in the cooling liquid and absorbs the heat of the cooling liquid. The heat pipe bundle is filled with organic compounds with a certain pressure. The solvent is used as a medium, and the medium evaporates after being heated, forming a plunger-type fluid between the gas and liquid phases in the heat pipe bundle, and the plunger-type fluid quickly transfers heat to the condensation area of the heat pipe bundle.

In some embodiments of the present invention, the oscillating heat pipe is a serpentine closed loop structure. The oscillating heat pipe involved in the present invention is a serpentine loop pipe, the medium is pre-filled in the oscillating heat pipe, and the medium can flow freely in the oscillating heat pipe from one end to the other end.

The evaporation area in the tube bundle of the oscillating heat pipe is heated, and the liquid in the tube bundle boils in the form of bubbles.

In some embodiments of the invention, the organic solvent is ethanol. Different organic solvents have different physical properties. Organic solvents such as methanol, ethanol, and acetone have larger specific heat capacity and latent heat of vaporization. As working fluid, the oscillating heat pipe has a good heat transfer effect, and at the same time, the dynamic viscosity is small, and the effect of forming a plunger during flow is good. Compared with the two other organic solvents, the boiling point of ethanol is higher to avoid the phenomenon of drying out.

In some embodiments of the present invention, the diameter of the oscillating heat pipe is 1-3 mm. When the pipe diameter is within the above range, the coexistence of liquid plugs and air bubbles can be achieved. The size of the pipe diameter affects the formation of gas-liquid plug fluids. Therefore, this application selects a suitable pipe diameter range to help realize the formation of gas-liquid plug flow. At the same time, it will not cause the flow resistance to be too large and affect the oscillation effect.

In some embodiments of the present invention, the tube bundle of the oscillating heat pipe is a branch tube bundle or a curved tube bundle. Oscillating heat pipes have the advantage of being variable in shape.

In some embodiments of the present invention, the number of channel bends of the oscillating heat pipe is not specifically limited, but should not be less than 15. The oscillating heat pipe is a serpentine loop structure. Too few elbows will affect the start of the heat pipe. With the increase of the number of elbows, the heat exchange area can be increased, the heat pipe is easier to start, the heat transfer performance is better, and the operation is more stable. , which can be arranged according to the actual situation.

In some embodiments of the present invention, the ratio of the length (or area) of the evaporation zone to the condensation zone of the oscillating heat pipe is 1:1.5-2.5; preferably 1:2.

In some embodiments of the present invention, the filling rate of the oscillating heat pipe is 35-50%. The liquid filling rate is the percentage of the total volume of the working medium in the total internal volume of the oscillating heat pipe. An appropriate liquid filling rate can improve the heat transfer performance and reduce the heat transfer resistance. In the present invention, the above liquid filling rate range helps to achieve Improve heat transfer performance.

The second aspect is the application of the above-mentioned data center immersion cooling device in the data center immersion cooling.

Below in conjunction with embodiment, the present invention is further described

Example 1

Three liquid-cooling cabinets are arranged in one computer room 1 , and several servers 5 are arranged in the liquid-cooling cabinets, and the several servers 5 are arranged in layers. The three liquid-cooling cabinets are respectively a first liquid-cooling cabinet 2 , a second liquid-cooling cabinet 3 , and a third liquid-cooling cabinet 4 , and the oscillating heat pipes provided in the first liquid-cooling cabinet 2 are arranged in an L-shape. The evaporation area 9 is located in the liquid cooling cabinet, the condensation area 7 is located outside the machine room, and the adiabatic area 8 is located in the connection area with the machine room and the liquid cooling cabinet. The side view of the oscillating heat pipe 6 of the first liquid cooling cabinet 1 is shown in FIG. 3 , the oscillating heat pipe is arranged in an L shape, and the evaporation area 9 of the oscillating heat pipe 6 absorbs the heat of the liquid cooling cabinet, and then dissipates the heat to the air in the condensation area 7 In the condensation zone 7 , the air flows and exchanges heat with the oscillating heat pipe 6 .

The oscillating heat pipe 6 provided in the second liquid-cooling cabinet 3 extends into the liquid-cooling cabinet from the top of the liquid-cooling cabinet, as shown in FIG. 2 . The tube bundles of the oscillating heat pipes 6 are straight tubes. The condensing area 7 and the adiabatic area 8 of the oscillating heat pipe 6 in the third liquid cooling cabinet 4 are arranged in an L-shape, and the oscillating heat pipe 9 in the evaporation area is in the form of an elbow, as shown in FIG. 4 . The arrangement of the oscillating heat pipes 6 of the third liquid cooling cabinet 4 is different from that of the oscillating heat pipes 6 of the first liquid cooling cabinet 2 . The adiabatic areas of the third liquid cooling cabinet 4 are concentrated in the middle of the third liquid cooling cabinet 4 , and then the oscillating heat pipes 6 of the evaporation area 9 are radially arranged inside the liquid cooling cabinet.

The height of the first liquid cooling cabinet 2 , the second liquid cooling cabinet 3 , and the third liquid cooling cabinet 4 is 2 m, and the diameter of the oscillating heat pipe 6 is 2 mm. The organic solvent medium in the tube bundle is ethanol, and the filling rate is 40%. There is no specific limit on the number of channel bends of the oscillating heat pipe, but it should not be less than 15.

The heat flux density in this example was 1000 W/cm ² .

The above descriptions are only preferred embodiments of the present invention, and are not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and changes. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims (10)

1. An immersed heat sink for a data center, characterized in that: it comprises a liquid cooling cabinet, a cooling liquid, and several oscillating heat pipes, the cooling liquid is filled in the liquid cooling cabinet, and the evaporation area of several oscillating heat pipes extends into the liquid cooling cabinet, and the oscillating heat pipes are oscillated. The condensation area of the heat pipe is located on the outside of the liquid cooling cabinet. The tube bundle of the oscillating heat pipe is filled with a medium, and the medium is an organic solvent. The connection area between the oscillating heat pipe and the side wall of the liquid cooling cabinet is an adiabatic area. 2 . The submerged heat sink for data center according to claim 1 , wherein the oscillating heat pipe is a serpentine closed loop structure. 3 . 3. The immersed heat sink for data center according to claim 1, wherein the organic solvent is ethanol. 4. The immersed heat dissipation device for a data center according to claim 1, wherein the diameter of the oscillating heat pipe is 1-3 mm. 5 . The immersion heat sink for data center according to claim 1 , wherein the tube bundles of the oscillating heat pipes are branch tube bundles or curved tube bundles. 6 . 6 . The submerged heat sink for data center according to claim 1 , wherein the number of channel bends of the oscillating heat pipe is not less than 15. 7 . 7 . The immersion heat sink for data center according to claim 1 , wherein the length ratio of the evaporation area and the condensation area of the oscillating heat pipe is 1:1.5-2.5. 8 . 8 . The immersion heat sink for data center according to claim 7 , wherein the length ratio of the evaporation area and the condensation area of the oscillating heat pipe is 1:2. 9 . 9. The immersed heat dissipation device for a data center according to claim 1, wherein the filling rate of the oscillating heat pipe is 35-50%. 10. The application of the data center immersion cooling device according to any one of claims 1-9 in the data center immersion cooling.

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