Immersion liquid cooling working medium composition and immersion liquid cooling working medium

Abstract

The invention relates to the field of immersion liquid cooling working media of data centers, in particular to an immersion liquid cooling working medium composition and an immersion liquid cooling working medium. According to the immersion liquid cooling working medium composition provided by the invention, the composite immersion liquid cooling working medium which is more balanced in compatibility with different non-metallic materials is obtained by selecting the base oil with proper types and properties and mixing the base oil according to a proper proportion, so that the problems that silicone oil is incompatible with VMQ and FVMQ and PAO and PAG are incompatible with EPDM are solved, and the service life of the composite immersion liquid cooling working medium composition is prolonged. The non-metal compatibility of EPDM and VMQ is effectively improved, meanwhile, the compatibility of other materials is not influenced, and the device can be widely applied to different immersion liquid cooling systems; meanwhile, after blending, the insulativity, flowability and heat-conducting property of the product all meet CDCC immersion liquid cooling standard requirements, and the product can be used for replacing other base oil products.

Description

Technical Field

[0001] The invention relates to the field of immersion liquid cooling working fluids, in particular to an immersion liquid cooling working fluid composition and an immersion liquid cooling working fluid. Background Art

[0002] Data center liquid cooling is divided into immersion liquid cooling, heat dissipation cold plate and other methods. Immersion cooling has high heat dissipation efficiency and can greatly reduce PUE. In recent years, it has been the focus of research by experts, scholars and industry users. It is a key branch of data center liquid cooling technology.

[0003] Single-phase immersion liquid cooling is a typical direct contact liquid cooling. The electronic equipment is immersed in the coolant, and the heat generated is directly transferred to the coolant. The heat conduction relies on the circulation of the liquid. Therefore, the compatibility of the immersion coolant with the material has a significant impact on whether the system can operate normally. At present, the most widely used and discussed immersion liquid cooling fluids in the field of single-phase immersion liquid cooling are mainly divided into hydrocarbons, organosilicon compounds and fluorocarbons. Hydrocarbons are mainly mineral oils and synthetic oils. There are many types of synthetic oils, mainly including PAO, CTL (charcoal to liquid), GTL (gas to liquid), polyethers (POE) and polyesters (PAG); organosilicon compounds are mainly dimethyl silicone oils (mostly low-viscosity silicone oils or modified silicone oils), and fluorocarbons are mainly fluorinated liquids.

[0004] In the process of implementing the present invention, the inventors found that the prior art has at least the following problems:

[0005] Different traditional base oils have poor compatibility with specific non-metals. For example, the three types of synthetic oils, PAO, CTL and PAG, have extremely poor compatibility with EPDM. There are many types of POE, and their compatibility with EPDM and VMQ varies according to their molecular weight and structure. Silicone oil has extremely poor compatibility with VMQ. The main reason for the poor compatibility is that the base oil and non-metals have similar molecular polarity or structure, which makes it easy for non-metals to absorb the base oil and swell, increasing their volume; or the additives in the non-metals precipitate and dissolve in the base oil, resulting in reduced quality of the non-metals and decreased mechanical properties.

[0006] Therefore, how to balance the compatibility with various non-metals by reasonably selecting base oils and ensuring that the physical properties of the final product meet the indicators is currently a major challenge. Summary of the invention

[0007] In view of this, an object of the present invention is to provide an immersion liquid cooling medium composition and an immersion liquid cooling medium, which have good compatibility with various non-metals and meet various physical properties.

[0008] The present invention provides an immersion liquid cooling working medium composition, which comprises, by weight:

[0009] First component oil: 20-70 parts; the first component oil is selected from dimethyl silicone oil, or the first component oil is selected from at least one of PAO, GTL oil or CTL oil;

[0010] Second component oil: 10-50 parts; the second component oil is selected from dimethyl silicone oil or PAG;

[0011] POE: 10~30 copies;

[0012] The first component oil and the second component oil are not dimethyl silicone oil at the same time.

[0013] The immersion liquid cooling working fluid composition provided by the present invention includes a first component oil, wherein the first component oil is selected from dimethyl silicone oil, or the first component oil is selected from at least one of PAO (polyalphaolefin), GTL oil (gas to oil) or CTL oil (coal to oil). For the selection of dimethyl silicone oil, according to the different classifications of the substituent groups on the polysiloxane chain, silicone oil can be divided into methyl silicone oil, phenyl silicone oil, polyether modified silicone oil, etc., and the CAS registration number of the dimethyl silicone oil of the present invention is 63148-62-9. If the first component oil is selected from dimethyl silicone oil, the molecular weight of the dimethyl silicone oil is 1000~3000, preferably 1000~2000, and more preferably 1000. At present, dimethyl silicone oil is mainly used in the immersion liquid cooling industry. Methyl silicone oil has good chemical stability, insulation, and good hydrophobic properties. Secondly, in order to ensure that the compound oil still maintains a low viscosity, the degree of polymerization of the silicone oil must be kept relatively low, and generally the molecular weight is kept between 1000~3000. As for the selection of PAO, GTL oil or CTL oil, considering that the lubricating oil used in the immersion liquid cooling industry is mostly low-viscosity oils such as PAO2, PAO4, GTL oil, etc., PAO2~6, GTL oil and CTL oil are preferably selected for compounding. If the first component oil is selected from PAO, the PAO is selected from one or more of PAO2, PAO3, PAO4, PAO5 or PAO6. Due to the differences between different brands of PAO on the market, PAO products from different manufacturers are compared, and PAO products selected from Mobil or Chevron are preferred.

[0014] The immersion liquid cooling working fluid composition provided by the present invention includes a second component oil, and the second component oil is selected from dimethyl silicone oil or PAG. For the selection of dimethyl silicone oil, based on the same reasons as above, if the second component oil is selected from dimethyl silicone oil, the molecular weight of the dimethyl silicone oil is 1000~3000. For the selection of PAG, PAG is also called polyether polyol (abbreviated as polyether), which is an organic polymer prepared by polyaddition reaction of an initiator (a compound containing an active hydrogen group) with ethylene oxide (EO), propylene oxide (PO), butylene oxide (BO), etc. in the presence of a catalyst. The main function of polyether is to act as a dispersant and solubilizer. The advantage is that it has good dispersibility for mixing different oils and good solubility for additives. It is mainly distinguished by the type of synthetic initiator and the content of each component. The largest polyether yield is achieved by using glycerol (propylene glycol) as the initiator and epoxide (generally PO and EO are used together), and various general polyether polyols are produced by changing the addition method of PO and EO (mixed or separate addition), addition ratio, addition order, etc. If the second component oil is selected from PAG, the PAG is a binary copolyether with a number average molecular weight of 1050-1550 synthesized with butanol as the initiator and PO / BO of 1-4, preferably a binary copolyether with a number average molecular weight of 1050 synthesized with butanol as the initiator and PO / BO of 2-3.

[0015] The immersion liquid cooling working fluid composition provided by the present invention includes POE, which is also called polyester. The advantages of POE are higher viscosity index, good fluidity at low temperature, and higher antioxidant stability. Its disadvantage is that it is easily hydrolyzed under high acid value. In certain embodiments of the present invention, the POE is selected from one or more of trimethylolpropane trioleate, dioctyl sebacate or dioctyl adipate. Among them, other common names of the trimethylolpropane trioleate are: ester of capric acid and 2-ethyl-2-(hydroxymethyl)-1,3-propanediol octyl salt, TMP trioleate, CAS registration number is 11138-60-6, and its structural formula is ,Depend on , and The structural formula of diisooctyl sebacate is , and its CAS registration number is 122-62-3. The structural formula of dioctyl adipate is , its CAS registration number is 123-79-5.

[0016] Preferably, the immersion liquid cooling working fluid composition provided by the present invention comprises, by mass, 20 to 50 parts of PAO, 10 to 50 parts of dimethyl silicone oil, and 10 to 30 parts of POE; or, 30 to 70 parts of PAO, 10 to 40 parts of PAG, and 10 to 30 parts of POE; or, 30 to 70 parts of dimethyl silicone oil, 10 to 40 parts of PAG, and 10 to 30 parts of POE. Wherein, the PAO, dimethyl silicone oil, PAG and POE are the same as those described above and will not be described in detail.

[0017] More preferably, the immersion liquid cooling working fluid composition provided by the present invention comprises, by mass, 40 to 50 parts of PAO2, 25 to 35 parts of dimethyl silicone oil, 15 to 25 parts of trimethylolpropane trioleate, or 25 to 35 parts of PAO4, 35 to 45 parts of dimethyl silicone oil, 20 to 30 parts of dioctyl sebacate, or 55 to 65 parts of PAO4, 10 to 15 parts of PAG, 10 to 30 parts of dioctyl adipate, or 45 to 55 parts of dimethyl silicone oil, 20 to 30 parts of PAG, and 10 to 30 parts of dioctyl sebacate. The dimethyl silicone oil and PAG are the same as those described above and will not be described in detail.

[0018] In some embodiments of the present invention, the immersion liquid cooling working fluid composition provided by the present invention includes, by mass, 45 parts of PAO2, 30 parts of dimethyl silicone oil, 20 parts of trimethylolpropane trioleate, or 30 parts of PAO4, 40 parts of dimethyl silicone oil, 25 parts of dioctyl sebacate, or 60 parts of PAO4, 10 parts of PAG, 25 parts of dioctyl adipate, or 50 parts of dimethyl silicone oil, 25 parts of PAG, and 20 parts of dioctyl sebacate. The dimethyl silicone oil and PAG are the same as above and will not be described in detail.

[0019] The present invention also provides an immersion liquid cooling medium, comprising: the immersion liquid cooling medium composition and additives described in any of the above technical solutions. In some embodiments of the present invention, it comprises: the immersion liquid cooling medium composition described in any of the above technical solutions and an antioxidant, wherein the weight percentage of the antioxidant is 0.01 part to 0.1 part; the antioxidant is selected from one or more of 2,6-di-tert-butyl-p-cresol, p-, p-diisooctyl diphenylamine, and N-phenyl-α-naphthylamine, preferably 2,6-di-tert-butyl-p-cresol.

[0020] The present invention also provides a method for preparing the above-mentioned immersion liquid cooling medium, comprising: mixing and stirring the immersion liquid cooling medium composition described in any of the above technical solutions and an additive to obtain the immersion liquid cooling medium. The temperature of the mixing and stirring in the present invention is 50°C to 70°C; the speed of the mixing and stirring is 100 r / min to 200 r / min, preferably 100 r / min to 150 r / min; the time of the mixing and stirring is 25 min to 50 min.

[0021] Compared with the prior art, the immersion liquid cooling medium composition and immersion liquid cooling medium provided by the present invention have at least the following beneficial effects:

[0022] The immersion liquid cooling medium composition provided by the present invention improves the disadvantage of extremely poor compatibility of a single immersion liquid cooling medium with specific non-metallic materials, so that it can be applied to different systems. The immersion liquid cooling medium after compounding can maintain the original safety performance and meet the use specifications of the data center. Specifically, the present invention is based on the problems that synthetic oils such as PAO, GTL oil, and PAG are incompatible with EPDM but compatible with VMQ; and dimethyl silicone oil is incompatible with silicone rubber but compatible with EPDM. By selecting base oils of suitable types and properties, a variety of base oils are mixed in a suitable proportion to obtain a composite immersion liquid cooling medium with more balanced compatibility with different non-metallic materials, which solves the problems of silicone oil incompatibility with VMQ and FVMQ, and PAO and PAG incompatibility with EPDM, effectively improves the non-metallic compatibility with EPDM and VMQ, and does not affect the compatibility of other materials, and can be widely used in different immersion liquid cooling systems; at the same time, after preparation, the insulation, fluidity and thermal conductivity of the product meet the requirements of the CDCC immersion liquid cooling specifications, and can be used to replace other base oil products. In summary, the immersion liquid cooling medium composition and the immersion liquid cooling medium provided by the present invention have good compatibility with various non-metals, and various physical properties meet the indicators. DETAILED DESCRIPTION

[0023] The present invention discloses an immersion liquid cooling fluid composition and an immersion liquid cooling fluid. Those skilled in the art can refer to the content of this article and appropriately improve the process parameters to achieve it. It is particularly important to point out that all similar substitutions and modifications are obvious to those skilled in the art, and they are all deemed to be included in the present invention. The methods and applications of the present invention have been described through preferred embodiments, and relevant personnel can obviously modify or appropriately change and combine the methods and applications of this article without departing from the content, spirit and scope of the present invention to implement and apply the technology of the present invention.

[0024] The raw materials used in Examples 1 to 4 of the present invention are as follows:

[0025] PAO (polyalphaolefin, including PAO2 from ExxonMobil, Chevron Corp., and PAO4 from ExxonMobil)

[0026] Dimethyl silicone oil (molecular weight 1000~3000) (The dimethyl silicone oil used in the experiment was purchased from MacLean Chemical Reagent Network, CAS No. 63148-62-9, the product is only marked with dynamic viscosity, the molecular weight is the measured value, and the molecular weight range corresponds to a dynamic viscosity range (at 40°C) of approximately 20 mPa·s~200 mPa·s)

[0027] POE: (Polyester lubricant, including TMP trioleate, dioctyl sebacate, dioctyl adipate)

[0028] PAG: (polyether lubricant, binary copolymer, PO / BO=2, Mn=1050) (independently synthesized according to literature data, the synthesis method refers to patent "CN104945613A" - Synthesis method description: add the formula amount of initiator and composite base catalyst (a mixture of diimine iron complex and potassium hydroxide) into the reactor in turn, replace with nitrogen 2~3 times, and evacuate to -0.09MPa; heat to 120℃ and start feeding, continuously introduce a mixture of alkylene oxides, control the reaction temperature to 120~140℃, and the reaction pressure <0.3MPa; after the feeding is completed, age and absorb until the reaction pressure is -0.06 ~ -0.09 MPa, evacuate for 3~5min, cool and discharge to obtain crude ether; add 1~5 wt% of deionized water and 1~3‰ polyether refining agent (magnesium silicate adsorbent) to the crude ether, stir at 75~95℃ for 1~2 h, and then vacuum dehydrate until the water content reaches 0.02 wt%, and then circulate and filter, and measure K after the filtrate is clear and transparent + The qualified finished product is obtained when the ion content is less than 3 mg / L.

[0029] Antioxidant: 2,6-di-tert-butyl-p-cresol (CAS No.: 128-37-0).

[0030] The test standard for non-metal compatibility can refer to the more authoritative CDCC immersion liquid cooling industry method. The specific test conditions are: 80℃, 7d, and the mass change rate and volume change rate are used to reflect the compatibility of immersion liquid cooling medium with non-metal. The calculation method is as follows:

[0031] The calculated mass change rate is obtained by formula 1:

[0032] Formula 1;

[0033] Wherein, m1 is the original mass of the sample, in milligrams (mg); m2 is the mass of the sample after immersion in liquid, in milligrams (mg).

[0034] The volume change rate is obtained by formula 2:

[0035] Formula 2;

[0036] Where V1 is the original volume of the sample in cubic centimeters (cm 3 ); V2 is the volume of the sample after immersion in liquid, in cubic centimeters (cm 3 )

[0037] The non-metal compatibility judgment index obtained based on the mass change rate is shown in Table 1:

[0038] Table 1

[0039]

[0040] The non-metal compatibility judgment index obtained based on the volume change rate is shown in Table 2:

[0041] Table 2

[0042]

[0043] Note: According to CDCC specifications, it is recommended that A-level liquid-cooled data centers use materials with A+, A-, and B compatibility. It is recommended that B-level liquid-cooled data centers use materials with B and C compatibility. It is recommended that C-level data centers use materials with C compatibility. It is not recommended that data centers use materials with D compatibility.

[0044] The present invention investigates and compares the non-metallic compatibility of several common base oils on the market and obtains the following Table 3:

[0045] Table 3

[0046]

[0047] Different base oils have different basic properties, such as flash point, acid value, additive solubility, etc. When mixing and blending, it is necessary to pay attention to the performance of the final product to meet the indicators. The indicators are shown in Table 4:

[0048] Table 4

[0049]

[0050] The present invention will be further described below in conjunction with embodiments:

[0051] Example 1

[0052] Formula composition: PAO2+dimethyl silicone oil+POE (TMP trioleate)+antioxidant (2,6-di-tert-butyl-p-cresol).

[0053] Synthesis process: Add 45 kg PAO2 base oil, 30 kg dimethyl silicone oil and 20 kg TMP trioleate into the reactor, control the temperature to 60°C, stir continuously at a speed of 120 r / min, then add 0.048 kg 2,6-di-tert-butyl-p-methylphenol in turn, stir for 30 min, and cool to obtain the immersion liquid cooling medium.

[0054] The non-metal compatibility of the immersion liquid cooling medium prepared in Example 1 was tested, and the results are shown in Table 5:

[0055] Table 5

[0056]

[0057] The physical properties of the immersion liquid cooling medium prepared in Example 1 were tested, and the results are shown in Table 6:

[0058] Table 6

[0059]

[0060] Example 2

[0061] Formula composition: PAO4 + dimethyl silicone oil + POE (dioctyl sebacate) + antioxidant (2,6-di-tert-butyl-p-cresol).

[0062] Synthesis process: Add 30 kg PAO4 base oil, 40 kg dimethyl silicone oil and 25 kg dioctyl sebacate into the reactor, control the temperature to 60°C, stir continuously at a speed of 120 r / min, then add 0.048 kg 2,6-di-tert-butyl-p-methylphenol in turn, stir for 30 min, and cool to obtain the immersion liquid cooling medium.

[0063] The non-metal compatibility of the immersion liquid cooling medium prepared in Example 2 was tested, and the results are shown in Table 7:

[0064] Table 7

[0065]

[0066] The physical properties of the immersion liquid cooling medium prepared in Example 2 were tested, and the results are shown in Table 8:

[0067] Table 8

[0068]

[0069] Example 3

[0070] Formula composition: dimethyl silicone oil + POE (dioctyl sebacate) + PAG (binary copolyether, PO / BO=2, Mn=1050) + antioxidant (2,6-di-tert-butyl-p-cresol).

[0071] Synthesis process: Add 50 kg of dimethyl silicone oil, 20 kg of dioctyl sebacate and 25 kg of PAG base oil into the reactor, control the temperature to 60°C, stir continuously at a speed of 120 r / min, then add 0.048 kg of 2,6-di-tert-butyl-p-methylphenol in turn, stir for 30 min, and cool to obtain the immersion liquid cooling medium.

[0072] The non-metal compatibility of the immersion liquid cooling medium prepared in Example 3 was tested, and the results are shown in Table 9:

[0073] Table 9

[0074]

[0075] The physical properties of the immersion liquid cooling medium prepared in Example 3 were tested, and the results are shown in Table 10:

[0076] Table 10

[0077]

[0078] Example 4

[0079] Formula composition: PAO4 + POE (dioctyl adipate) + PAG base oil (binary copolyether, PO / BO=2, Mn=1050) + antioxidant (2,6-di-tert-butyl-p-cresol)

[0080] Synthesis process: Add 60 kg PAO4 base oil, 25 kg dioctyl adipate and 10 kg PAG base oil into the reactor, control the temperature to 60°C, stir continuously at a speed of 120 r / min, then add 0.048 kg 2,6-di-tert-butyl-p-methylphenol in turn, stir for 30 min, and cool to obtain the immersion liquid cooling medium.

[0081] The non-metal compatibility of the immersion liquid cooling medium obtained in Example 4 was tested, and the results are shown in Table 11:

[0082] Table 11

[0083]

[0084] The physical properties of the immersion liquid cooling medium prepared in Example 4 were tested, and the results are shown in Table 12:

[0085] Table 12

[0086]

[0087] The compatibility of the above Examples 1 to 4 and PAO and silicone oil with various non-metals is summarized in Table 13:

[0088] Table 13

[0089]

[0090] It can be seen from the above content that the immersion liquid cooling medium composition and the immersion liquid cooling medium provided by the present invention have good compatibility with various non-metals, and at the same time various physical properties meet the indicators.

[0091] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes according to the technical scheme and inventive concept of the present invention within the technical scope disclosed by the present invention, which should be covered by the protection scope of the present invention.

Claims

1. An immersion liquid cooling working medium composition, characterized in that: In parts by mass, including: First component oil: 20-70 parts; the first component oil is selected from dimethyl silicone oil, or the first component oil is selected from at least one of PAO, GTL oil or CTL oil; Second component oil: 10-50 parts; the second component oil is selected from dimethyl silicone oil or PAG; POE: 10~30 copies; The first component oil and the second component oil are not dimethyl silicone oil at the same time.

2. The immersion liquid cooling medium composition according to claim 1, characterized in that: If the first component oil is selected from dimethyl silicone oil, the molecular weight of the dimethyl silicone oil is 1000-3000; If the first component oil is selected from PAO, the PAO is selected from one or more of PAO2, PAO3, PAO4, PAO5 or PAO6; If the second component oil is selected from dimethyl silicone oil, the molecular weight of the dimethyl silicone oil is 1000-3000; If the second component oil is selected from PAG, the PAG is a binary copolyether synthesized with a PO / BO ratio of 1 to 4.

3. The immersion liquid cooling working medium composition according to claim 2, characterized in that: If the second component oil is selected from PAG, the PAG is a binary copolyether with a number average molecular weight of 1050-1550 synthesized with butanol as an initiator and a PO / BO ratio of 1-4.

4. The immersion liquid cooling working medium composition according to claim 1, characterized in that: The POE is selected from one or more of trimethylolpropane trioleate, dioctyl sebacate or dioctyl adipate.

5. The immersion liquid cooling working medium composition according to any one of claims 1 to 4, characterized in that: In parts by mass, it includes: PAO: 20-50 parts; dimethyl silicone oil: 10-50 parts; POE: 10-30 parts; Or, including: PAO: 30~70 parts; PAG: 10~40 parts; POE: 10~30 parts; Alternatively, it comprises: dimethyl silicone oil: 30-70 parts; PAG: 10-40 parts; POE: 10-30 parts.

6. The immersion liquid cooling medium composition according to claim 5, characterized in that: In parts by mass, it comprises: PAO2: 40-50 parts; dimethyl silicone oil: 25-35 parts; trimethylolpropane trioleate: 15-25 parts; Alternatively, it comprises: PAO4: 25-35 parts; dimethyl silicone oil: 35-45 parts; dioctyl sebacate: 20-30 parts; Alternatively, it comprises: PAO4: 55-65 parts; PAG: 10-15 parts; dioctyl adipate: 10-30 parts; Alternatively, it comprises: dimethyl silicone oil: 45-55 parts; PAG: 20-30 parts; dioctyl sebacate: 10-30 parts.

7. The immersion liquid cooling working medium composition according to claim 6, characterized in that: In parts by mass, it includes: PAO2: 45 parts; dimethyl silicone oil: 30 parts; trimethylolpropane trioleate: 20 parts; Alternatively, it comprises: PAO4: 30 parts; dimethyl silicone oil: 40 parts; dioctyl sebacate: 25 parts; Alternatively, it comprises: PAO4: 60 parts; PAG: 10 parts; dioctyl adipate: 25 parts; Alternatively, it comprises: dimethyl silicone oil: 50 parts; PAG: 25 parts; dioctyl sebacate: 20 parts.

8. Immersion liquid cooling medium, characterized in that: include: The immersion liquid cooling medium composition according to any one of claims 1 to 7; and additives.

9. The immersion liquid cooling medium according to claim 8, characterized in that: include: The immersion liquid cooling medium composition according to any one of claims 1 to 7; And antioxidant: 0.01~0.1 parts.

10. The immersion liquid cooling medium according to claim 9, characterized in that: The antioxidant is selected from one or more of 2,6-di-tert-butyl-p-cresol, p-,p-diisooctyldiphenylamine, and N-phenyl-α-naphthylamine.

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