Cooling liquid for liquid cooling system of data center and preparation method and application thereof

Abstract

The present application relates to the technical field of cooling liquid, and proposes a cooling liquid for a data center liquid cooling system, a preparation method and application thereof.The cooling liquid for the data center liquid cooling system comprises the following components by weight: 100 parts of base oil, 4-6 parts of heat-conducting filler, 2-4 parts of additive, 0.05-0.08 parts of defoaming agent, and 0.5-1 part of corrosion inhibitor; the additive comprises polyisobutyl succinimine and alkyl phosphate ester in a mass ratio of 1:2-4.The thermal conductivity of the cooling liquid is greater than or equal to 0.220 W / (m*K), and the kinematic viscosity and copper corrosion performance are relatively high, so that the cooling liquid can effectively meet the heat dissipation requirements of the data center.

Description

Technical Field

[0001] This invention relates to the field of coolant technology, specifically to coolants for data center liquid cooling systems, their preparation methods, and applications. Background Technology

[0002] With the rapid iteration of digital technologies such as artificial intelligence, cloud computing, and big data, the demand for computing power has exploded. As a core infrastructure supporting the development of the digital economy, data centers are continuously upgrading their construction scale and technological level, with increasingly higher power densities per rack. Therefore, these devices continuously release a large amount of heat during operation, making liquid cooling systems the core method for heat dissipation in data centers. Coolant, as the core heat transfer medium of liquid cooling systems, directly determines the heat dissipation efficiency, operational stability, and equipment lifespan of the system, and is the core support for the large-scale application of liquid cooling technology.

[0003] Currently, the coolants used in data center liquid cooling systems are mainly organic coolants represented by base oils. They have good insulation and good compatibility with equipment materials, but they generally have the shortcoming of low thermal conductivity, which makes them unsuitable for the high-intensity heat dissipation requirements of high power density data centers, thus limiting their application scope.

[0004] Therefore, there is a need to develop a coolant for data center liquid cooling systems that has good insulation and thermal conductivity. Summary of the Invention

[0005] This invention proposes a coolant for a data center liquid cooling system, its preparation method, and its application. This coolant has a high thermal conductivity.

[0006] To achieve this objective, the present invention adopts the following technical solution: In a first aspect, the present invention provides a coolant for a data center liquid cooling system, comprising the following raw materials in parts by weight: 100 parts base oil, 4-6 parts thermally conductive filler, 2-4 parts additives, 0.05-0.08 parts defoamer, and 0.5-1 part corrosion inhibitor; wherein the additives include polyisobutyl succinimide and alkyl phosphate in a mass ratio of 1:2-4.

[0007] In one embodiment, the alkyl phosphate comprises hexadecyl phosphate and dodecyl phosphate in a mass ratio of 1:1 to 2.

[0008] In one embodiment, the thermally conductive filler comprises one or both of silicon nitride and boron nitride.

[0009] In one embodiment, the thermally conductive filler is composed of thermally conductive filler A1 with a particle size of 20-30 nm, thermally conductive filler A2 with a particle size of 40-50 nm, and thermally conductive filler A3 with a particle size of 60-80 nm, in a mass ratio of 1:1.5:2~3.

[0010] In one embodiment, the base oil includes one or both of GTL base oil and PAO base oil.

[0011] In one embodiment, the base oil consists of GTL base oil and PAO base oil in a mass ratio of 9:1 to 5.

[0012] In one embodiment, the defoamer comprises polyether-modified silicone.

[0013] In one embodiment, the corrosion inhibitor comprises benzotriazole.

[0014] Secondly, the present invention provides a method for preparing the above-mentioned coolant for a data center liquid cooling system, which includes the following steps: mixing the raw materials of the coolant at 50~55°C for 30~50 minutes to obtain the coolant for a data center liquid cooling system.

[0015] Thirdly, the present invention provides an application of the coolant for the above-mentioned data center liquid cooling system, including the coolant of the first aspect or the coolant prepared by the preparation method of the second aspect.

[0016] To improve the thermal conductivity of coolant used in data center liquid cooling systems, this invention adds an additive comprising polyisobutyl succinimide and alkyl phosphate in a mass ratio of 1:2~4 to the coolant, which has the following beneficial effects: In this invention, the addition of polyisobutyl succinimide can coat the surface of the thermally conductive filler through nucleophilic and charge adsorption in the oil phase, thereby inhibiting the aggregation and sedimentation of the thermally conductive filler. The addition of alkyl phosphate can wet the surface of the thermally conductive filler, and due to the steric hindrance effect of its molecular structure, it can further disperse the thermally conductive filler. Thus, under the combined effect of the two, the overall thermal conductivity of the coolant can be improved. Detailed Implementation

[0017] The technical solutions of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0018] Regarding coolants used in data center liquid cooling systems, base oil coolants are commonly selected. To improve thermal conductivity, thermally conductive fillers are added to the coolant. However, due to their own agglomeration and poor dispersibility, the thermal conductivity of these fillers cannot be fully utilized. Therefore, there is a problem that the thermal conductivity of coolants used in data center liquid cooling systems cannot be significantly improved. This invention provides a coolant for data center liquid cooling systems by adding an additive composed of polyisobutyl succinimide and alkyl phosphates, which can initially improve the thermal conductivity of the coolant. Furthermore, the type of alkyl phosphate is specified, using an alkyl phosphate composed of hexadecyl phosphate and dodecyl phosphate, which can further improve the thermal conductivity of the coolant. Furthermore, limiting the thermally conductive filler to consist of three different particle sizes further improves the thermal conductivity of the coolant.

[0019] Specifically, in order to better understand the technical solution of the present invention, it is described in the following parts.

[0020] Part One This invention provides a coolant for a data center liquid cooling system, comprising the following raw materials in parts by weight: 100 parts base oil, 4-6 parts thermally conductive filler, 2-4 parts additives, 0.05-0.08 parts defoamer, and 0.5-1 part corrosion inhibitor; the additives include polyisobutyl succinimide and alkyl phosphate in a mass ratio of 1:2-4, wherein the thermally conductive filler can be any value from 2 parts, 2.2 parts, 2.5 parts, 2.8 parts, or 3 parts, or any two values. The range between; for example, the additive can be any point value and the range between any two point values ​​from 2 parts, 2.5 parts, 3 parts, 3.5 parts, 4 parts; for example, the defoamer can be any point value and the range between any two point values ​​from 0.05 parts, 0.06 parts, 0.07 parts, 0.08 parts; for example, the corrosion inhibitor can be any point value and the range between any two point values ​​from 0.5 parts, 0.6 parts, 0.7 parts, 0.8 parts, 0.9 parts, 1.0 parts.

[0021] In some embodiments of the present invention, the alkyl phosphate ester includes hexadecyl phosphate and dodecyl phosphate in a mass ratio of 1:1 to 2, for example, any point value from 1:1, 1:1.1, 1:1.2, 1:1.3, 1:1.4, 1:1.5, 1:1.6, 1:1.7, 1:1.8, 1:1.9, 1:2 and any range between any two point values.

[0022] The addition of alkyl phosphate in this invention can reduce interfacial tension, prevent the agglomeration of thermally conductive fillers, and improve the uniformity of filler dispersion, thereby improving the overall thermal conductivity.

[0023] In some embodiments of the present invention, the thermally conductive filler includes one or both of silicon nitride and boron nitride.

[0024] In some embodiments of the present invention, the thermally conductive filler is composed of thermally conductive filler A1 with a particle size of 20-30 nm, thermally conductive filler A2 with a particle size of 40-50 nm, and thermally conductive filler A3 with a particle size of 60-80 nm, in a mass ratio of 1:1.5:2-3. For example, it can be any point value or the range between any two point values ​​from 1:1.5:2, 1:1.5:2.2, 1:1.5:2.4, 1:1.5:2.6, 1:1.5:2.8, 1:1.5:3.

[0025] In this invention, the three different particle sizes of the thermally conductive filler form a gradient distribution, which can reduce voids, increase packing density, reduce thermal resistance, and improve heat transfer efficiency. This, in turn, increases the contact area between the thermally conductive fillers and improves the thermal conductivity of the coolant. By limiting the amount of the three different particle sizes of thermally conductive fillers added, the dispersibility of the thermally conductive fillers can be improved, thereby improving heat transfer efficiency and increasing the thermal conductivity of the coolant.

[0026] In some embodiments of the present invention, the base oil includes one or both of GTL base oil and PAO base oil.

[0027] In some embodiments of the present invention, the base oil is composed of GTL base oil and PAO base oil in a mass ratio of 9:1 to 5, for example, any point value or range between any two point values ​​from 9:1, 9:1.5, 9:2, 9:2.5, 9:3, 9:3.5, 9:4, 9:4.5, 9:5.

[0028] In some embodiments of the present invention, the defoamer is not particularly limited. As understood by those skilled in the art, the defoamer is used to eliminate foam, inhibit foam generation, and ensure the stable operation of the liquid cooling system. The defoamer includes polyether-modified organosilicon.

[0029] In some embodiments of the present invention, the corrosion inhibitor is not particularly limited. As understood by those skilled in the art, the corrosion inhibitor is used to inhibit the corrosion of metal parts by the coolant, protect the substrate in the liquid cooling system, avoid the chain of negative effects caused by corrosion, and ensure the long-term stable operation of the liquid cooling system. Corrosion inhibitors include benzotriazole.

[0030] Part Two The invention also provides a method for preparing a coolant for a data center liquid cooling system. The method for preparing the coolant includes the following steps: mixing the raw materials of the coolant at 50-55°C for 30-50 minutes to obtain the coolant for the data center liquid cooling system. The 50-55°C can be any point value or any range between any two points from 50°C, 51°C, 52°C, 53°C, 54°C, and 55°C. The 30-50 minutes can be any point value or any range between any two points from 30 minutes, 32 minutes, 35 minutes, 38 minutes, 40 minutes, 42 minutes, 45 minutes, 48 ​​minutes, and 50 minutes.

[0031] Part Three The present invention also provides an application of a coolant for a data center liquid cooling system, including the coolant of the first aspect or the coolant prepared by the preparation method of the second aspect. method The following methods are used to determine the performance defined in the examples and comparative examples.

[0032] (1) Thermal conductivity: The test was conducted in accordance with ASTM D7896, "Standard Test Method for Determining Thermal Conductivity, Thermal Diffusivity and Volumetric Heat Capacity of Engine Coolant and Related Fluids by Transient Hot-Wire Liquid Thermal Conductivity Method", with a test condition of 50°C.

[0033] (2) Kinematic viscosity: The test was conducted in accordance with GB / T 265-1988 "Determination of kinematic viscosity and calculation of dynamic viscosity of petroleum products" and the test conditions were 40℃.

[0034] (3) Copper corrosion performance: The test was conducted in accordance with GB / T 5096-2017 "Test method for corrosion of copper sheet in petroleum products". The test conditions were 60℃ and the test time was 24h.

[0035] (4) Dielectric constant: The test shall be conducted in accordance with the method in ASTM D924 "Method for testing the dielectric loss of liquid insulating materials" at 25℃.

[0036] Material Unless otherwise specified, all materials used in the embodiments and comparative examples of this invention are commercially available, for example... Polyisobutyl succinimide, model T154, manufactured by Jinzhou Shengda Chemical Co., Ltd. Polyether-modified silicone, item number W-745, manufactured by Guangzhou Zhongwan New Materials Co., Ltd. GTL base oil, model Shell GTL420; PAO base oil, model PAO-6, manufactured by ExxonMobil.

[0037] illustrate In the following description: polyisobutyl succinimide is designated as additive A; hexadecyl phosphate is designated as additive B1; dodecyl phosphate is designated as additive B2; 20~30nm silicon nitride is designated as thermally conductive filler A1; 40~50nm silicon nitride is designated as thermally conductive filler A2; and 60~80nm silicon nitride is designated as thermally conductive filler A3.

[0038] Example 1 The raw material composition of a coolant for a data center liquid cooling system is shown in Table 1 below. The preparation method of the coolant for a data center liquid cooling system is as follows: the raw materials of the coolant are mixed at 50°C for 50 minutes to obtain the coolant.

[0039] Example 2 The raw material composition of a coolant for a data center liquid cooling system is shown in Table 1 below. The preparation method of the coolant for a data center liquid cooling system is as follows: the raw materials of the coolant are mixed at 55°C for 30 minutes to obtain the coolant.

[0040] Except for the additives used in the raw materials of the coolant for the data center liquid cooling system, Examples 3-8 and Comparative Examples 1-3 are the same as in Example 1. The additives used in Examples 3-5 and Comparative Examples 1-3 are recorded in Table 2.

[0041] Table 1 Raw materials of coolant in Examples 1-2

[0042] Table 2. Additives in Examples 3-8 and Comparative Examples 1-3

[0043] Table 3 Thermal conductivity of the coolant in Examples 1-8 and Comparative Examples 1-3

[0044] As shown in Table 3, Comparative Examples 1 and 2 had their additive compositions changed, while Comparative Example 3 did not add any additives. The results showed that the thermal conductivity of the coolant in Comparative Examples 1 and 3 was lower than that in Example 1, indicating that the additive composed of polyisobutyl succinimide and alkyl phosphate can improve the thermal conductivity of the coolant. Furthermore, compared to Examples 6-8, Examples 1 and 4 had their alkyl phosphate compositions changed, resulting in higher thermal conductivity of the coolant in Examples 6-8 than in Examples 1 and 4. This indicates that using alkyl phosphate composed of hexadecyl phosphate and dodecyl phosphate can further improve the thermal conductivity of the coolant.

[0045] Except for the thermally conductive filler, which is different from that in Example 1, Examples 9-13 are the same as in Example 1. The thermally conductive fillers in Examples 9-13 are recorded in Table 4. Table 4 Thermally conductive fillers in Examples 9-13

[0046] Table 5 Thermal conductivity of the coolant in Examples 9-13

[0047] Compared with Example 1, Examples 9-11 consist of three thermally conductive fillers with different particle sizes, while Examples 1, 12, and 13 consist of only one type of thermally conductive filler with a single particle size. As a result, the thermal conductivity of the coolant in Examples 9-11 is higher than that in Examples 1 and 12-13, indicating that three types of thermally conductive fillers with different particle sizes can improve the thermal conductivity of the coolant.

[0048] Table 6. Kinematic viscosity of coolant in Examples 1-3

[0049] The copper corrosion test results show that the copper sheet corrosion level of the coolant in Examples 1-3 is 1a.

[0050] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A coolant for a data center liquid cooling system, characterized in that, The raw material comprises the following components in parts by weight: 100 parts base oil, 4-6 parts thermally conductive filler, 2-4 parts additives, 0.05-0.08 parts defoamer, and 0.5-1 part corrosion inhibitor; the additives include polyisobutyl succinimide and alkyl phosphate in a mass ratio of 1:2-4.

2. The coolant for a data center liquid cooling system according to claim 1, characterized in that, The alkyl phosphate esters include hexadecyl phosphate ester and dodecyl phosphate ester in a mass ratio of 1:1 to 2.

3. The coolant for a data center liquid cooling system according to claim 1, characterized in that, The thermally conductive filler includes one or both of silicon nitride and boron nitride.

4. The coolant for a data center liquid cooling system according to claim 1, characterized in that, The thermally conductive filler consists of thermally conductive filler A1 with a particle size of 20-30 nm, thermally conductive filler A2 with a particle size of 40-50 nm, and thermally conductive filler A3 with a particle size of 60-80 nm, in a mass ratio of 1:1.5:2~3.

5. The coolant for a data center liquid cooling system according to claim 1, characterized in that, The base oil includes one or both of GTL base oil and PAO base oil.

6. The coolant for a data center liquid cooling system according to claim 5, characterized in that, The base oil is composed of GTL base oil and PAO base oil in a mass ratio of 9:1 to 5.

7. The coolant for a data center liquid cooling system according to claim 1, characterized in that, The defoamer includes polyether-modified silicone.

8. The coolant for a data center liquid cooling system according to claim 1, characterized in that, The corrosion inhibitor includes benzotriazole.

9. A method for preparing a coolant for a data center liquid cooling system, used to prepare the coolant for a data center liquid cooling system as described in any one of claims 1 to 8, characterized in that, Includes the following steps: The raw materials of the coolant are mixed at 50-55°C for 30-50 minutes to obtain a coolant for a data center liquid cooling system.

10. An application of a coolant in a data center liquid cooling system, characterized in that, The coolant includes the coolant according to any one of claims 1 to 8 or the coolant prepared by the preparation method according to claim 9.

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