Alkylmethylsiloxane liquid immersion cooling medium

Abstract

The process includes the step of immersing the device in a cooling fluid, wherein the cooling fluid comprises an alkyl modified silicone oil having the following average chemical structure (I): (CH3)3SiO-[(CH3)2)SiO]m-[R(CH3)SiO]n-Si(CH3)3(I), wherein R is an alkyl and substituted alkyl having at least 6 and at least 17 carbon atoms in each case; the subscript m has a value of at least 1 and at least 22, the subscript n has a value of at least 1, and the sum of m+n is greater than 5 and at least 50.

Description

Technology Field

[0001] The present invention relates to a process and system using an immersion cooling fluid containing alkylmethylsiloxane. Background Technology

[0002] As data center equipment becomes more powerful, it generates more heat, which can impair its lifespan and performance. Circulating air has been used to remove heat from data center equipment. However, circulating air is not sufficiently efficient to adequately cool newer and more powerful equipment. More recently, heat transfer fluids circulating within enclosed paths through data center equipment have been used to remove heat. The fluid does not come into direct contact with the equipment but rather flows through fluid conduits within the equipment. This is considered "indirect" fluid cooling of the equipment. While circulating enclosed fluids are more efficient at heat removal than circulating air, they are still not as efficient as desired.

[0003] Most recently, "direct" fluid cooling for data center equipment has been introduced as a more efficient cooling method. Direct fluid cooling cools equipment by using a fluid coolant that comes into direct contact with the data center equipment. Typically, the equipment is immersed in a fluid coolant that circulates around and through the equipment. This is an efficient means of cooling the equipment. However, ensuring that electronic equipment comes into direct contact with a fluid is a challenging issue. Direct fluid cooling is rather a specialized application that requires specialized cooling fluids. Ideally, the cooling fluid should be thermally conductive and also a high dielectric (i.e., a poor electrical conductor). It is also important that the cooling fluid is compatible with the equipment it comes into contact with; that is, the cooling fluid should not decompose, alter, or otherwise affect the equipment it comes into contact with. It is also desirable for the fluid to be environmentally safe, such as having low flammability and low toxicity.

[0004] Presumably, the majority of fluids in the market intended for use as direct cooling fluids for data center equipment are fluorinated materials, such as those sold by 3M under the names 3M™ Fluorinert™ Electronic Liquids and 3M™ Novec™ Engineered Fluids. "3M," "Fluorinert," and "Novec" are trademarks of the 3M company. These fluorinated materials tend to be efficient at heat removal. However, these fluorinated materials have relatively low boiling points (below 200°C, mostly below 150°C). According to their advertising literature, the low boiling point of fluorinated materials limits their application to temperatures below 175°C. The low boiling point also implies that they evaporate relatively easily, which can lead to undesirable exposure of operators and the environment to the fluorinated materials.

[0005] Mineral oil is another fluid that can be used as a direct cooling fluid for data center equipment. Mineral oil is desirable due to its low cost. However, its application as a direct cooling fluid also presents significant challenges. Mineral oil is only moderately efficient for heat removal on its own and typically contains impurities such as sulfur, which can lead to corrosion of data center equipment. Concerns regarding the flammability of mineral oil and its degradation over time have also been raised. Furthermore, mineral oil tends to swell ethylene propylene diene monomer (EPDM) rubber, which, when used as a direct cooling fluid in contact with capacitors, can lead to the failure of capacitors within the server and eventually the server itself. Therefore, there is a risk of damage to electronic data center equipment exposed to mineral oil as a direct cooling fluid.

[0006] Polyalphaolefin (PAO) synthetic oil is another option for direct cooling fluids. While it generally contains fewer impurities than mineral oil, concerns regarding PAO synthetic oils regarding flammability and degradation over time still exist. Like mineral oil, PAO also tends to swell EPDM rubber, and therefore there is a risk of damage to electronic data center equipment exposed to PAO synthetic oil as a direct cooling fluid.

[0007] Polydimethylsiloxane (PDMS) is another option as a direct cooling fluid, offering a lower cost option compared to fluorinated fluids, good compatibility with non-silicone components in data center equipment, relatively low flammability, and high stability against degradation. However, PDMS tends to swell silicone rubber materials and weaken the peel strength of silicone rubber adhesive materials, making it easier for components attached to the silicone rubber to detach. Silicone-based materials are commonly used in electronic equipment as thermal conductive greases and gap fillers for thermal bonding components. Swelling of these materials can cause them to detach from thermal bonding components, thereby reducing thermal bonding and heat transfer between the thermal conductive components.

[0008] It is desirable to find a cooling fluid for specialized applications of direct cooling fluids for cooling electronic data center equipment. The cooling fluid must avoid the issues associated with fluorinated fluids, mineral oils, PAO synthetic oils, and PDMS. In particular, it is desirable to find a direct cooling fluid that possesses the following characteristics:

[0009] ㆍ It is a liquid at 25°C and a pressure of 101 kilopascals (760 millimeters of mercury pressure);

[0010] ㆍ 100 square millimeters (mm) per minute at 25℃ 2 Having kinematic viscosity of less than / s;

[0011] ㆍ Does not significantly swell or imbibition EPDM or silicone rubber;

[0012] ㆍ Having a flash point greater than 150℃; and

[0013] ㆍ May not contain halogen.

[0014] The present invention provides a direct contact (immersion) cooling process and system using a cooling fluid suitable for direct cooling applications, such as those involving electronic data center equipment. The fluid surprisingly simultaneously possesses the following characteristics: (i) it is a liquid at 25°C and a pressure of 101 kilopascals (kPa); and (ii) at 25°C, a rate of 100 square millimeters (mm²) per minute. 2 It has a kinematic viscosity of less than / s; (iii) does not significantly swell or impregnate EPDM or silicone rubber; (iv) has a flash point greater than 150°C; and (v) may be halogen-free.

[0015] The cooling fluid of the present invention comprises alkyl-modified PDMS ("alkylmethylsiloxane"). Concerns regarding alkylmethylsiloxane in direct cooling systems may be residual silyl hydride (SiH) and free hydrocarbon components. Residual SiH is undesirable because it hydrolyzes silanol (SiOH) and tends to release hydrogen gas. The generation of hydrogen gas in the presence of electronic components is an undesirable safety hazard. The presence of silanol is a polar group that negatively affects the dielectric properties of siloxane, making it less efficient as a direct cooling fluid. Free hydrocarbon components can cause phase haziness or even phase separation in the cooling fluid and may increase swelling or immersion of EPDM rubber. Surprisingly, the alkylmethylsiloxane of the present invention not only acquires the fluid characteristics mentioned in the previous paragraph, but also has a hydrogen content for the SiH group of less than 10 parts by weight (ppm) per 10 million weights of the alkylmethylsiloxane, and a SiH concentration of less than 20 weight percent (weight%) of the free hydrocarbon concentration based on the weight of the alkylmethylsiloxane.

[0016] In a first embodiment, the present invention is a process comprising the step of immersing an apparatus in a cooling fluid, wherein the cooling fluid comprises an alkyl modified silicone oil having the following average chemical structure (I):

[0017] (CH3)3SiO-[(CH3)2)SiO] m -[R(CH3)SiO] n -Si(CH3)3(I)

[0018] In the above formula, R is an alkyl and a substituted alkyl in each case, and the R group has 6 or more and simultaneously 17 or fewer carbon atoms; the subscript m has a value of 1 or more and simultaneously less than 22, the subscript n has a value of 1 or more, and the sum of m+n is greater than 5 and simultaneously less than 50.

[0019] European Patent EP0641849B1 discloses the use of alkylmethylsiloxane fluids as heat transfer fluids. However, the aforementioned reference does not mention the specialized applications of direct cooling fluids, or the advantages provided by specialized applications of direct cooling compared to PDMS or other direct cooling fluids. Furthermore, it has been found that not all alkylmethylsiloxane fluids, even those taught as heat transfer fluids in European Patent EP0641849B1, are suitable as direct cooling fluids. In particular, polydimethylsiloxane having chemical structure (I) (where R is a one-carbon alkyl) is not an acceptable material because it causes swelling and immersion of silicone rubber. A short-chain alkyl for R is expected to perform similarly to polydimethylsiloxane. The embodiments of the present invention demonstrate that when the R group has six or more carbons, it is an acceptable immersion cooling fluid.

[0020] In a second aspect, the present invention is a liquid immersion cooling system comprising a device in a cooling fluid, wherein the cooling fluid comprises an alkyl modified silicone oil having the following average chemical structure (I):

[0021] (CH3)3SiO-[(CH3)2)SiO] m -[R(CH3)SiO] n -Si(CH3)3(I)

[0022] In the above formula, R is an alkyl and substituted alkyl having 6 or more and simultaneously 17 or fewer carbon atoms in each case; the subscript m has a value of 1 or more and simultaneously less than 22, the subscript n has a value of 1 or more, and the sum of m+n is greater than 5 and simultaneously less than 50. Specific details for implementing the invention

[0023] Where a date is not specified along with a test method number, the test method refers to the most recent test method as of the priority date of this document. References to test methods include both references to the testing association and the test method number. The following test method abbreviations and identifiers apply herein: ASTM refers to the ASTM International Method; EN refers to the European Standard; DIN refers to the German Standardization Association; ISO refers to the International Organization for Standardization; and UL refers to the Underwriters Laboratory.

[0024] The product identified by their trademark name refers to a composition available by their trademark name on the priority date of this document.

[0025] "Multiple" means two or more. "And / or" means "and or alternatively." All ranges include end points unless otherwise specified. Unless otherwise specified, all weight-percentage (weight%) values ​​are for the weight of the composition, and all volume-percentage (volume%) values ​​are for the volume of the composition.

[0026] Unless otherwise specified, the “kinematic viscosity” of individual polysiloxanes is determined by ASTM D 445 using a glass capillary Cannon-Fenske type viscometer at 25°C (°F).

[0027] The flash point of the material is determined using a Cleveland open cup (COC). A COC measurement is performed with approximately 70 milliliters of sample. The expected flash point is set to 100°C. The temperature is increased from 25°C to approximately 44°C at a rate of 14 to 17°C per minute, and then increased at a rate of 5 to 6°C per minute until the flash point is identified.

[0028] Whether the fluid "significantly swells" or "significantly infiltrates" EPDM and silicone rubber is determined using the compatibility test procedure presented in the following Examples section.

[0029] The concentration of SiH in the fluid is determined by combining 1.0 g of the sample material and 8.0 milligrams of pyrazine (as an internal standard) with 1.5 milliliters of deuterated chloroform to obtain a homogeneous solution. A portion of the solution is added to a 5 mm nuclear magnetic resonance (NMR) tube, and a 1H NMR spectrum is collected at 25°C on a Bruker AVANCE II 400 megahertz NMR instrument with a zg pulse program, D1=15 sec, and NS=32. In the spectrum, the combined intensity of the proton signal for SiH (a single peak from 4.65 to 4.78 ppm) provides the ratio of the number of hydrogen atoms to Si atoms relative to pyrazine. The concentration of hydrogen to silicon atoms can be calculated relative to the total weight of the sample material.

[0030] Determine the concentration of free hydrocarbons in the fluid using gas-phase chromatography / mass spectrometry (GC / MS). Dilute approximately 0.5 g of the fluid sample in approximately 4.5 g of toluene. Measure and record the weight of the components using an analytical balance. Analyze the diluted sample by GC / MS using standard hydrocarbon chemicals for calibration, specifically those used as reactants in preparing the sample, such as 1-hexene, 1-octene, 1-dodecene, 1-tetradecene, etc. Use an Agilent 7890A gas chromatography system with a DB-5ms column (30 meters x 0.25 millimeter inner diameter x 0.25 micrometer film); a constant helium carrier gas flow of 1.0 milliliter per minute; oven parameters of 40°C for 6 minutes, a gradient of 15°C / minute to 280°C, and a 10-minute hold during a total run time of 32.0 minutes; A 1 microliter sample is injected through an autosampler system and a 10 microliter syringe; the injector temperature is 280°C with a split ratio of 50:1; the detector is an MSD with an MS source temperature of 230°C, an MS Quad temperature of 150°C, an Aux-2 temperature of 280°C, and an acquisition mode: scan mass of 29 to 350.

[0031] "Alkyl" refers to a hydrocarbon radical that can be derived by removing a hydrogen atom from an alkane. Alkyls can be linear or branched.

[0032] "Substituted alkyl" refers to a radical similar to an alkyl except that a non-hydrogen group is present in place of one or more hydrogen atoms. For example, an alkyl in which one or more hydrogen atoms have been replaced by an aromatic group (e.g., phenyl or benzyl) or a halogen, such as fluorine, is considered to be a substituted alkyl.

[0033] In a first embodiment, the present invention is a process comprising the step of immersing a device in a cooling fluid. As used herein, "immersion" may refer to partially immersing the device in the cooling fluid without completely submerging it, or, preferably, to completely submerging the device in the cooling fluid. In the same way, terms such as "immerse," "immerse," etc. may refer to the device being less submerged than completely, or the device being completely submerged.

[0034] In the broadest scope of the present invention, the device may be any article. Preferably, the device is a heat-generating article or a component attached to a heat-generating article. For example, the device may be a heat sink attached (combined) to a heat-generating article, may be a heat-generating article, or may be both a heat-generating article and a heat sink attached to a heat-generating article. The present invention is particularly applicable to a device that is an electronic device. The device may be a computer or part of a computer. As used herein, "computer" refers to any one or more of any combination of components of a computer, and any one or more of any combination of components is selected from, for example, a power distribution component (e.g., an electronic converter), a server comprising a circuit board having a plurality of electronic components fixed on top and present in a housing, the circuit board itself, an electronic random access memory component, a memory storage component, a central processing unit (CPU), and a graphics processing unit.

[0035] The cooling fluid may include or be composed of alkyl modified silicone oil. The cooling fluid typically comprises alkyl modified silicone oil in a weight percentage (weight%) greater than 50% relative to the weight of the cooling fluid, preferably 75% or more, 90% or more, 95% or more, 98% or more, and even 99% or more. The cooling fluid may be composed of alkyl modified silicone oil.

[0036] Alkyl modified silicone oil has the following average chemical structure (I):

[0037] (CH3)3SiO-[(CH3)2)SiO] m -[R(CH3)SiO] n -Si(CH3)3(I)

[0038] In the above formula,

[0039] R is independently selected from an alkyl group and a substituted alkyl group in each case, and the R group is 6 or more, 7 or more, 8 or more, 9 or more, 10 or more, 11 or more, 12 or more, 13 or more, 14 or more, 15 or more, even 16 or more, and at the same time contains 17 or fewer, 16 or fewer, 15 or fewer, 14 or fewer, 13 or fewer, 12 or fewer, 11 or fewer, 10 or fewer, 9 or fewer, 8 or fewer, or even 7 or fewer carbon atoms; preferably, R is selected from the group consisting of an alkyl group having the number of carbon atoms specified above and the substituted group(s) on the alkyl and alkyl are substituted alkyl groups having a combined number of carbon atoms within the range specified above. For example, the R group may be a phenyl-substituted alkyl, and the total number of carbon atoms is the sum of the number of alkyl carbon atoms and the number of phenyl carbon atoms.

[0040] The subscript m can have a value of 1 or more, 2 or more, or even 3 or more, and at the same time is typically less than 22, 20 or less, 15 or less, 10 or less, 9 or less, 8 or less, 7 or less, 6 or less, or even 5 or less.

[0041] The subscript n has a value of 1 or more, preferably 2 or more, 3 or more, 4 or more, or even 5 or more, while typically being less than 30, and may be 25 or less, 20 or less, 15 or less, 10 or less, 9 or less, 8 or less, 7 or less, or even 6 or less.

[0042] The sum of subscripts m and n ("m+n") may have a value of 5 or more, 6 or more, 7 or more, 8 or more, 9 or more, 10 or more, 15 or more, 20 or more, and even 25 or more, while having a value of less than 50, 40 or less, 30 or less, 25 or less, 20 or less, 15 or less, 10 or less, or even 9 or less.

[0043] Identity of alkyl modified silicone oil including identity of the R group, and values ​​for m and n by standard method 1 H, 13 C, and 29 It is determined using Si nuclear magnetic resonance spectroscopy.

[0044] Alkyl modified silicone oil is 100 square millimeters per second (mm²) 2 Having a kinematic viscosity of less than / s or centistokes (cSt), and 75 mm 2 / s or less, 50 mm 2 / s or less, preferably 30 mm 2 / s or less, and more preferably 20 mm 2 It can have a kinematic viscosity of / s or less, and 10 mm 2 It can be less than / s, and at the same time, preferably 5 mm 2 It has a kinematic viscosity greater than / s. The selection of R, m, and n values ​​to obtain kinematic viscosity within these ranges is easily attainable.

[0045] It was found that the R group in chemical structure (I) preferably has six or more carbon atoms. When R contains fewer than six carbon atoms, the alkyl modified silicone oil is expected to have characteristics very similar to polydimethylsiloxane, swelling and impregnating silicone rubber. At the same time, it was found that the R group in chemical structure (I) must have 17 or fewer carbon atoms, because when R has 18 or more carbon atoms, the material becomes a wax rather than a fluid at 25°C and 101 kPa pressure. The R group can be substituted or non-substituted. For example, the R group can be halogenated (substituted with one or more halogens) or non-halogenated (no halogen). Therefore, the alkyl modified silicone oil may be halogen-free, and the cooling fluid as a whole may be halogen-free. The R group may be a phenyl-substituted alkyl group, wherein the alkyl component has fewer than 6 carbon atoms, and the total number of carbon atoms in the R group is 6, which is within the required range specified above. Alternatively, the R group may be an alkyl group having a number of carbons within the required range specified above. The R group may be linear or branched. A branched structure may be desirable for lowering the melting point of the alkyl-modified silicone oil.

[0046] The alkyl modified silicone oil must have a value for the subscript n greater than or equal to 1, or it is not an alkyl modified silicone oil but rather a polydimethylsiloxane.

[0047] The value for m+n is limited by the fact that the alkyl-modified silicone oil is desired to have kinematic viscosity within the range specified above.

[0048] Particularly preferably, the alkyl modified silicone oil is selected from the group consisting of any one or more combinations of any combination of any alkyl modified silicone oil having chemical structure (I), wherein m is 3, n is 6, and R is a linear alkyl group having 6 to 16 carbon atoms; m is 5, n is 3, and R is a linear alkyl having 10 carbon atoms; and m is 3, n is 4, and R is a 3-carbon alkyl having a middle carbon substituted with a phenyl group.

[0049] Alkyl modified silicone oil can be synthesized by the hydrosilylation reaction described in the following Examples section.

[0050] The cooling fluid may comprise or be composed of an alkyl modified silicone oil or even a combination of one or more alkyl modified silicone oils. Alternatively, the cooling fluid may comprise or be composed of a mixture of one or more additional fluids and an alkyl modified silicone oil(s) that satisfies the requirements of an immersion cooling fluid. For example, the cooling fluid may comprise an alkyl modified silicone oil and a fluorocarbon fluid, provided that the fluorocarbon fluid has a boiling point greater than 150°C.

[0051] Preferably, the cooling fluid contains less than 20 weight percent (weight%), preferably 10 weight% or less, 5 weight% or less, and 1 weight% or less of free hydrocarbons, and may be free hydrocarbons, wherein the weight percent of hydrocarbons is relative to the weight of the alkyl-modified silicone oil. "Free hydrocarbons" refers to hydrocarbons that are not chemically bonded to the non-hydrocarbon components (for example, alkyls on a siloxane molecule are not "free hydrocarbons," but hexane or 1-hexane would be). Since free hydrocarbons can cause swelling of organic materials such as EPDM rubber, it is desirable to minimize free hydrocarbons. Free hydrocarbons can also lower the flash point of the composition.

[0052] Preferably, the alkyl modified silicone oil contains minimal SiH functionality, where present. The degree of SiH functionality is determined by measuring the weight percentage of H relative to the weight of the alkyl modified silicone oil. The weight percentage of H is preferably less than 10 parts by weight (ppm) per million parts by weight relative to the weight of the alkyl modified silicone oil, preferably 9 ppm or less, 9 ppm or less, 7 ppm or less, 6 ppm or less, 6 ppm or less, 5 ppm or less, 4 ppm or less, 3 ppm or less, 2 ppm or less, and 1 ppm or less. The alkyl modified silicone oil may not have SiH functionality.

[0053] The cooling fluid may contain any one or more combinations of optional components, such as antioxidants. Antioxidants may be desirable for increasing the thermal stability of the cooling fluid, particularly for antioxidants that stabilize alkyl groups. Suitable antioxidants are typically aromatic amines and / or hindered phenolics. Examples of suitable antioxidants include those selected from the group consisting of those available under the following trade names: IRGANOX™ 1076 and IRGANOX™ 1010. IRGANOX is a trademark of BASF SE.

[0054] The process of the present invention comprises the step of immersing the device in a cooling fluid comprising or composed of alkyl modified silicone oil, and may further comprise one or more additional steps. For example, the process may comprise the step of cooling the cooling fluid (alkyl modified silicone oil). For example, the cooling fluid may be non-fluid within a vessel having the device immersed in the cooling fluid, while the vessel cools the cooling fluid. The cooling fluid may circulate around the device immersed in the cooling fluid within a vessel (circulation tank), and the vessel cools the cooling fluid. The cooling fluid may be cooled in a separate cooling unit and may circulate between the cooling unit and the vessel containing the device immersed in the cooling fluid, so that the cooling fluid circulates around the device during a cycle, passes through the cooling unit, and then returns to the device.

[0055] In another aspect, the present invention is a liquid immersion cooling system. In this context, "system" refers to a set of components associated with one another in a manner to achieve a specific purpose. In the present invention, the liquid immersion cooling system comprises components that serve to achieve immersion cooling of a device immersed in a cooling fluid.

[0056] Liquid immersion cooling systems of various complexity are known in the industry, and the broadest category of the present invention includes any immersion cooling system.

[0057] The system of the present invention comprises a device in a cooling fluid, and the cooling fluid comprises or is composed of the alkyl modified silicone oil described herein. The device is as described herein.

[0058] The system may further include a cooler that removes heat from the cooling fluid. The cooler may be a refrigerated vessel in which the cooling fluid forms a cooling bath in which the device is immersed. The system may further include a circulation component that causes the cooling fluid to flow around the device immersed therein. The circulation component may be an impeller submerged in the cooling fluid that causes the fluid to flow around the device immersed therein, while the fluid and the device exist within a single vessel that may or may not be a cooler. Alternatively or additionally, the circulation component may be a circulation pump or other circulation component that causes the cooling fluid to flow between the vessel holding the cooling fluid and the device immersed in the cooling fluid and another vessel or device that cools the cooling fluid during a cycle.

[0059] In particular, the cooling fluid preferably comes into direct contact with the device immersed in the cooling fluid in both the process and the system of the present invention.

[0060] Examples

[0061] Table 1 presents the materials to be used in the following examples. DOWSIL, XIAMETER, and NORDEL are trademarks of The Dow Chemical Company. SpectraSyn is a trademark of Exxon Mobil Corporation. Ultra-S is a trademark of S-Oil Corporation.

[0062] [Table 1]

[0063]

[0064] SiH Siloxane and Synthesis Method

[0065] SiH Siloxane 1: (CH 3 ) 3 SiO[H(CH 3 )SiO] 1 Si(CH 3) 3

[0066] It is prepared by trifluoromethanesulfonic acid-catalyzed equilibration of 70 wt% hexamethyldisiloxane and 30 wt% trimethylsiloxy-terminated methylhydrogen polysiloxane 2 as described in U.S. Patent US20060264602A1 and the technology mentioned herein.

[0067] SiH Siloxane 2: (CH 3 ) 3 SiO[(CH 3 ) 2 Si)] 3 [H(CH 3 )SiO] 5 Si(CH 3 ) 3

[0068] As described in U.S. Patent US20060264602A1 and the technology mentioned herein, it is prepared by trifluoromethanesulfonic acid-catalyzed equilibration of 14.9 wt% hexamethyldisiloxane, 62.9 wt% octamethylcyclotetrasiloxane, and 22.2 wt% trimethylsiloxy-terminated methylhydrogen polysiloxane 2.

[0069] SiH Siloxane 3: (CH 3 ) 3 SiO[H(CH 3 )SiO] 17 Si(CH 3 ) 3

[0070] As described in U.S. Patent US20060264602A1 and the technology mentioned herein, it is prepared by trifluoromethanesulfonic acid-catalyzed equilibration of 10.11 wt% hexamethyldisiloxane and 89.89 wt% trimethylsiloxy-terminated methylhydrogen polysiloxane 2.

[0071] SiH Siloxane 4: (CH 3 ) 3 SiO[(CH 3 ) 2 Si)] 3 [H(CH 3 )SiO] 6 Si(CH 3 ) 3

[0072] As described in U.S. Patent US20060264602A1 and the technology mentioned herein, it is prepared by trifluoromethanesulfonic acid-catalyzed equilibration of 18.8 wt% hexamethyldisiloxane, 31.9 wt% octamethylcyclotetrasiloxane, and 49.3 wt% trimethylsiloxy-terminated methylhydrogen polysiloxane 2.

[0073] SiH Siloxane 5: (CH 3 ) 3 SiO[(CH 3 ) 2 Si)] 22 [H(CH 3 )SiO] 2 Si(CH 3 ) 3

[0074] As described in U.S. Patent US20060264602A1 and the technology mentioned herein, it is prepared by trifluoromethanesulfonic acid-catalyzed equilibration of 8.26 wt% hexamethyldisiloxane, 84.91 wt% octamethylcyclotetrasiloxane, and 6.83 wt% trimethylsiloxy-terminated methylhydrogen polysiloxane 2.

[0075] SiH Siloxane 6: (CH 3 ) 3 SiO[(CH 3) 2 Si)] 16 [H(CH 3 )SiO] 38 Si(CH 3 ) 3

[0076] As described in U.S. Patent US20060264602A1 and the technology mentioned herein, it is prepared by trifluoromethanesulfonic acid-catalyzed equilibration of 1.81 wt% hexamethyldisiloxane, 32.41 wt% octamethylcyclotetrasiloxane, and 65.78 wt% trimethylsiloxy-terminated methylhydrogen polysiloxane 2.

[0077] SiH Siloxane 7: (CH 3 ) 3 SiO[(CH 3 ) 2 Si)] 35 [H(CH 3 )SiO] 35 Si(CH 3 ) 3

[0078] As described in U.S. Patent US20060264602A1 and the technology mentioned herein, it is prepared by trifluoromethanesulfonic acid-catalyzed equilibration of 7.11 wt% hexamethyldisiloxane fluid (available from The Dow Chemical Company as DOWSIL™ SH 200 fluid 10 cSt), 47.15 wt% octamethylcyclotetrasiloxane, and 45.74 wt% trimethylsiloxy-terminated methylhydrogen polysiloxane.

[0079] SiH Siloxane 8: (CH 3 ) 3 SiO[(CH 3 ) 2 Si)] 25 [H(CH 3 )SiO] 55 Si(CH 3 ) 3

[0080] As described in U.S. Patent US20060264602A1 and the technology mentioned herein, it is prepared by trifluoromethanesulfonic acid-catalyzed equilibration of 34.25 wt% of hexamethyldisiloxane cyclic compounds (available from The Dow Chemical Company as DOWSIL™ 344 fluid) and 64.75 wt% of trimethylsiloxy-terminated methylhydrogen polysiloxane 1.

[0081] SiH Siloxane 9: (CH 3 ) 3 SiO[(CH 3 ) 2 Si)] 84 [H(CH 3 )SiO] 14 Si(CH 3 ) 3

[0082] As described in U.S. Patent US20060264602A1 and the technology mentioned herein, it is prepared by trifluoromethanesulfonic acid-catalyzed equilibration of 1.76 wt% hexamethyldisiloxane, 85.8 wt% octamethylcyclotetrasiloxane, and 12.44 wt% trimethylsiloxy-terminated methylhydrogen polysiloxane 1.

[0083] SiH Siloxane 10: (CH 3 ) 3 SiO[(CH 3 ) 2 Si)] 3 [H(CH 3 )SiO] 3 Si(CH 3 ) 3

[0084] As described in U.S. Patent US20060264602A1 and the technology mentioned herein, it is prepared by trifluoromethanesulfonic acid-catalyzed equilibration of 25.13 wt% hexamethyldisiloxane, 36.63 wt% octamethylcyclotetrasiloxane, and 38.24 wt% trimethylsiloxy-terminated methylhydrogen polysiloxane 1.

[0085] Alkyl methylsiloxane sample

[0086] Sample 1: (CH 3 ) 3 SiO[(CH 3 ) 2 Si)] 3 [(C 6 H 13 )(CH 3 )SiO] 6 Si(CH 3 ) 3

[0087] 246.2 grams (g) of 1-hexane and 78.5 milligrams (mg) of Pt-47D catalyst are added into a three-necked round-bottom flask at 25°C under nitrogen purging. While stirring, 300.0 g of SiH4 siloxane 4 is added dropwise at 70°C, while controlling the addition to maintain the temperature in the range of 70 to 80°C. After the addition is complete, stirring is continued for 4 hours. The obtained mixture is distilled to remove residual 1-hexene. The remaining material is Sample 1.

[0088] Sample 2: (CH 3 ) 3 SiO[(CH 3) 2 Si)] 3 [(C 8 H 17 )(CH 3 )SiO] 6 Si(CH 3 ) 3

[0089] 328.25 g of 1-octene and 78.5 mg of Pt-47D catalyst are added into a three-necked round-bottom flask at 25°C under nitrogen purging. While stirring, 300.0 g of SiH4 siloxane 4 is added dropwise at 70°C, while controlling the addition to maintain the temperature in the range of 70 to 80°C. After the addition is complete, stirring is continued for 4 hours. The obtained mixture is distilled to remove residual 1-octene. The remaining material is Sample 2.

[0090] Sample 3: (CH 3 ) 3 SiO[(CH 3 ) 2 Si)] 3 [(C 12 H 25 )(CH 3 )SiO] 6 Si(CH 3 ) 3

[0091] 492.7 g of 1-dodecene and 78.5 mg of Pt-47D catalyst are added into a three-necked round-bottom flask at 25°C under nitrogen purging. While stirring, 300.0 g of SiH4 siloxane 4 is added dropwise at 70°C, while controlling the addition to maintain the temperature in the range of 70 to 80°C. After the addition is complete, stirring is continued for 4 hours. The reaction product is washed three times with 100 ml (mL) of petroleum ether to remove residual 1-dodecene. Subsequently, the obtained mixture is distilled to remove residual petroleum ether. The remaining material is Sample 3.

[0092] Sample 4: (CH 3 ) 3 SiO[(CH 3 ) 2 Si)] 3 [(C 14 H 29 )(CH 3 )SiO] 6 Si(CH 3 ) 3

[0093] 574.4 g of 1-tetradecene and 78.5 mg of Pt-47D catalyst are added into a three-necked round-bottom flask at 25°C under nitrogen purging. While stirring, 300.0 g of SiH4 siloxane 4 is added dropwise at 70°C, while controlling the addition to maintain the temperature in the range of 70 to 80°C. After the addition is complete, stirring is continued for 4 hours. The reaction product is washed three times with 100 mL of petroleum ether to remove residual 1-tetradecene. Subsequently, the obtained mixture is distilled to remove residual petroleum ether. The remaining material is Sample 4.

[0094] Sample 5: (CH 3 ) 3 SiO[(CH 3 ) 2 Si)] 3 [(C 16 H 33 )(CH 3 )SiO] 6 Si(CH 3 ) 3

[0095] 657.0 g of 1-hexadecene and 78.5 mg of Pt-47D catalyst were added into a three-necked round-bottom flask at 25°C under nitrogen purging. While stirring, 300.0 g of SiH4 siloxane 4 was added dropwise at 70°C, while controlling the addition to maintain the temperature in the range of 70 to 80°C. After the addition was completed, stirring was continued for 4 hours. The obtained material is Sample 5.

[0096] Sample 5 has a boiling point exceeding 250°C and 45 mm 2 It has a kinematic viscosity of / s at 25°C, a melting point of 15 to 20°C, a flash point above 200°C, and a saturated water absorption of less than 300 parts by weight per million parts by weight of the sample fluid, is transparent, colorless, has a low toxicity risk factor, a global warming potential of 0 (or approximately 0), an ozone depletion potential of 0 (or approximately 0), and exhibits negligible signs of degradation during use.

[0097] Sample 6: (CH 3 ) 3 SiO[(CH 3 ) 2 Si)] 3 [(C 18 H 37 )(CH 3 )SiO] 6 Si(CH 3) 3

[0098] 369.3 g of 1-octadecene and 65.0 mg of Pt-47D catalyst are added into a three-necked round-bottom flask at 25°C under nitrogen purging. While stirring, 150.0 g of SiH siloxane 1 is added dropwise at 70°C, while controlling the addition to maintain the temperature in the range of 70 to 80°C. After the addition is complete, stirring is continued for 4 hours. The obtained product is wax at 25°C and is therefore not suitable as a cooling fluid. This establishes that the R group in chemical structure (I) must contain fewer than 18 carbon atoms.

[0099] Sample 7: (CH 3 ) 3 SiO[(CH 3 ) 2 Si)] 22 [(C 8 H 17 )(CH 3 )SiO] 2 Si(CH 3 ) 3

[0100] 44.3 g of 1-octene and 78.5 mg of Pt-47D catalyst are added into a three-necked round-bottom flask at 25°C under nitrogen purging. While stirring, 300.0 g of SiH siloxane 5 is added dropwise at 70°C, while controlling the addition to maintain the temperature in the range of 70 to 80°C. After the addition is complete, stirring is continued for 4 hours. The obtained product is distilled to reduce the residual 1-octene to 2% by weight of the product composition.

[0101] Sample 8: (CH 3 ) 3 SiO[(CH3 ) 2 Si)] 3 [(C 6 H 13 )(CH 3 )SiO] 4.5 [(C 14 H 29 )(CH 3 )SiO] 1.5 Si(CH 3 ) 3

[0102] 114.9 g of 1-tetradecene and 78.5 mg of Pt-47D catalyst are added into a three-necked round-bottom flask at 25°C under nitrogen purging. While stirring, 300.0 g of SiH4 siloxane 4 is added dropwise at 70°C, while controlling the addition to maintain the temperature in the range of 70 to 80°C. After the addition is complete, stirring is continued for 2 hours. Subsequently, 196.9 g of 1-hexene is added dropwise into the flask at 60°C under nitrogen purging, and after the addition is complete, the solution is maintained at 70°C for 2 hours. The obtained mixture is distilled to remove residual 1-hexene. The residual material is Sample 8.

[0103] Sample 9: (CH 3 ) 3 SiO[(CH 3 ) 2 Si)] 3 [(C 6 H 13 )(CH 3 )SiO] 3 [(C 14 H 29 )(CH3 )SiO] 3 Si(CH 3 ) 3

[0104] 229.8 g of 1-tetradecene and 78.5 mg of Pt-47D catalyst are added into a three-necked round-bottom flask at 25°C under nitrogen purging. While stirring, 300.0 g of SiH4 siloxane 4 is added dropwise at 70°C, while controlling the addition to maintain the temperature in the range of 70 to 80°C. After the addition is complete, stirring is continued for 2 hours. Subsequently, 147.7 g of 1-hexene is added dropwise into the flask at 60°C under nitrogen purging, and after the addition is complete, the solution is maintained at 70°C for 2 hours. The obtained mixture is distilled to remove residual 1-hexene. The residual material is Sample 9.

[0105] Sample 10: (CH 3 ) 3 SiO[(CH 3 ) 2 Si)] 3 [(C 6 H 13 )(CH 3 )SiO] 1.5 [(C 14 H 29 )(CH 3 )SiO] 4.5 Si(CH 3 ) 3

[0106] 344.6 g of 1-tetradecene and 78.5 mg of Pt-47D catalyst are added into a three-necked round-bottom flask at 25°C under nitrogen purging. While stirring, 300.0 g of SiH4 siloxane 4 is added dropwise at 70°C, while controlling the addition to maintain the temperature in the range of 70 to 80°C. After the addition is complete, stirring is continued for 2 hours. Subsequently, 98.5 g of 1-hexene is added dropwise into the flask at 60°C under nitrogen purging, and after the addition is complete, the solution is maintained at 70°C for 2 hours. The obtained mixture is distilled to remove residual 1-hexene. The residual material is Sample 10.

[0107] Sample 11: (CH 3 ) 3 SiO[(CH 3 ) 2 Si)] 3 [(C 8 H 17 )(CH 3 )SiO] 3 [(C 14 H 29 )(CH 3 )SiO] 3 Si(CH 3 ) 3

[0108] 344.7 g of 1-tetradecene and 78.5 mg of Pt-47D catalyst are added into a three-necked round-bottom flask at 25°C under nitrogen purging. While stirring, 300.0 g of SiH4 siloxane 4 is added dropwise at 70°C, while controlling the addition to maintain the temperature in the range of 70 to 80°C. After the addition is complete, stirring is continued for 2 hours. Subsequently, 131.3 g of 1-octene is added dropwise into the flask at 60°C under nitrogen purging, and after the addition is complete, the solution is maintained at 70°C for 2 hours. The obtained mixture is distilled to remove residual 1-octene. The residual material is Sample 11.

[0109] Sample 12: (CH 3 ) 3 SiO[(CH 3 ) 2 Si)] 3 [(C 10 H 21 )(CH 3 )SiO] 5 Si(CH 3 ) 3

[0110] 410.6 g of 1-decene and 78.5 mg of Pt-47D catalyst are added into a three-necked round-bottom flask at 25°C under nitrogen purging. While stirring, 300.0 g of SiH4 siloxane 10 is added dropwise at 70°C, while controlling the addition to maintain the temperature in the range of 70 to 80°C. After the addition is complete, stirring is continued for 4 hours. The reaction product is washed three times with 100 ml (mL) of petroleum ether to remove residual 1-decene. Subsequently, the obtained mixture is distilled to remove residual petroleum ether. The remaining material is Sample 12.

[0111] Sample 13: (CH3 ) 3 SiO[(CH 3 ) 2 Si)] 16 [(C 6 H 13 )(CH 3 )SiO] 38 Si(CH 3 ) 3

[0112] 100.0 g of 1-hexene and 36.0 mg of Pt-47D catalyst are added into a three-necked round-bottom flask at 25°C under nitrogen purging. While stirring, 100 g of SiH4 siloxane 6 is added dropwise at 70°C, while controlling the addition to maintain the temperature in the range of 70 to 80°C. After the addition is complete, stirring is continued for 4 hours. The obtained mixture is distilled to remove residual 1-hexene. The remaining material is Sample 13.

[0113] Sample 14: (CH 3 ) 3 SiO[(CH 3 ) 2 Si)] 35 [(C 8 H 17 )(CH 3 )SiO] 35 Si(CH 3 ) 3

[0114] 109.4 g of 1-octene and 36.0 mg of Pt-47D catalyst are added into a three-necked round-bottom flask at 25°C under nitrogen purging. While stirring, 100 g of SiH4 siloxane 7 is added dropwise at 70°C, while controlling the addition to maintain the temperature in the range of 70 to 80°C. After the addition is complete, stirring is continued for 4 hours. The obtained mixture is distilled to remove residual 1-octene. The residual material is Sample 14.

[0115] Sample 15: (CH 3 ) 3 SiO[(CH 3 ) 2 Si)] 25 [(C 8 H 17 )(CH 3 )SiO] 55 Si(CH 3 ) 3

[0116] 280.0 g of SiH siloxane 8 and 110 mg of Pt-47D catalyst were added into a 1000 ml three-necked round-bottom flask equipped with a reflux condenser, a stirring bar, a thermometer, and an addition funnel. Under nitrogen purging and stirring, 486.0 g of 1-octene was added dropwise while maintaining a temperature in the range of 70 to 90°C. After the addition was completed, stirring was continued at 80°C for 4 hours. The reaction product was stripped under vacuum at 150°C for 3 hours to remove excess 1-octene, its isomers, and low-volatility cyclic siloxanes. The obtained product was filtered through a Zeta-Plus filter to obtain Sample 15.

[0117] Sample 16: (CH 3 ) 3 SiO[(CH3 ) 2 Si)] 84 [(C 8 H 17 )(CH 3 )SiO] 14 Si(CH 3 ) 3

[0118] 546.0 g of SiH siloxane 9 and 110 mg of Pt-47D catalyst were added into a 1000 ml three-necked round-bottom flask equipped with a reflux condenser, a stirring bar, a thermometer, and an addition funnel. Under nitrogen purging and stirring, 180.0 g of 1-octene was added dropwise while maintaining a temperature in the range of 70 to 90°C. After the addition was completed, stirring was continued at 80°C for 4 hours. The reaction product was stripped under vacuum at 150°C for 3 hours to remove excess 1-octene, its isomers, and low-volatility cyclic siloxanes. The obtained product was filtered through a Zeta-Plus filter to obtain Sample 16.

[0119] Sample 17: (CH 3 ) 3 SiO[(CH 3 ) 2 Si)] 3 [(CH 2 C(CH) 3 -Ph)(CH 3 )SiO] 3 Si(CH 3 ) 3

[0120] 351.0 g of SiH siloxane 10 and 110 mg of Pt-47D catalyst are added into a 1000 ml three-necked round-bottom flask equipped with a reflux condenser, stirring bar, thermometer, and addition funnel. Under nitrogen purging and stirring, 299.0 g of alpha-methyl styrene is added dropwise while maintaining a temperature in the range of 70 to 90°C. After the addition is complete, stirring is continued at 80°C for 4 hours. Another 135.0 g of alpha-methyl styrene and 330 mg of Pt-47D catalyst are added to the reaction mixture while maintaining at 80°C for 4 hours. The mixture is stripped under vacuum at 150°C for 3 hours to remove excess alpha-methyl styrene and low-volatility cyclic siloxane. The obtained product is filtered through a Zeta-Plus filter to obtain Sample 17.

[0121] Sample 18: 80 / 20 weight formulation of Sample 1 and Sample 13

[0122] 160 g of sample 1 and 40 g of sample 13 are mixed for 30 minutes using a magnetic stirring bar to obtain a clear fluid, which is sample 18.

[0123] Sample 19: 80 / 20 weight formulation of Sample 2 and Sample 14

[0124] 160 g of sample 2 and 40 g of sample 14 are mixed for 30 minutes using a magnetic stirring bar to obtain a clear fluid, which is sample 19.

[0125] Sample 20: (CH 3 ) 3 SiO[(C 8 H 17 )(CH 3 )SiO] 8 Si(CH 3 ) 3 Note: m=0 and n=8

[0126] 175.0 g of 1-octene and 36.0 mg of Pt-47D catalyst are added into a three-necked round-bottom flask at 25°C under nitrogen purging. While stirring, 100.0 g of SiH3 siloxane is added dropwise at 70°C, while controlling the addition to maintain the temperature in the range of 70 to 80°C. After the addition is complete, stirring is continued for 4 hours. The obtained mixture is distilled to remove residual 1-octene. The remaining material is Sample 20.

[0127] Sample 21: (CH 3 ) 3 SiO[(C 14 H 29 )(CH 3 )SiO] 8 Si(CH 3 ) 3 Note: m=0 and n=8

[0128] 153.0 g of 1-tetradecene and 18.0 mg of Pt-47D catalyst are added into a three-necked round-bottom flask at 25°C under nitrogen purging. While stirring, 50.0 g of SiH3 siloxane is added dropwise at 70°C, while controlling the addition to maintain the temperature in the range of 70 to 80°C. After the addition is complete, stirring is continued for 4 hours. The remaining material is Sample 21.

[0129] Sample 22: (CH 3 ) 3 SiO(C 8 H 17 )(CH 3 )SiOSi(CH 3 ) 3 Note: m=0 and n=1

[0130] This material is commercially available from Gelest as TM-081.

[0131] Characterization of samples

[0132] Each of the 19 samples is characterized for viscosity, flash point, SiH residue, and hydrocarbon residue using the procedures described herein. The samples are further characterized for whether they are liquid at 25°C and for the compatibility of the samples with silicone rubber and EPDM rubber using the following compatibility test procedures. The results of the sample characterization are presented in Table 3 below.

[0133] Compatibility test. Test samples of EPDM rubber and silicone rubber are cut to a length of 5 centimeters, a width of 0.5 centimeters, and a thickness of 2 millimeters, respectively. The initial length and initial weight of each sample material are recorded. Within the container, the test samples are fully immersed in a single fluid. The container is sealed and heated to 50°C. The container is stored at 50°C for 4 months, after which the samples are removed and blot-dried using absorbent paper on both sides of the test samples. The length and weight of the samples are recorded. Changes in length and weight relative to before immersion are determined. An increase in length exceeding 15% (final length exceeding 115% of the initial length) is considered "significant swelling." An increase in weight exceeding 50% (final weight exceeding 150% of the initial weight) is considered "significant immersion." Significant swelling and / or significant swelling result in failure in the compatibility test.

[0134] For comparison purposes, polyalphaolefin, mineral oil, polydimethylsiloxane (PDMS), and the reference fluid of fluorocarbon fluid 1 were also characterized in compatibility tests and have the following results in Table 2:

[0135] [Table 2]

[0136]

[0137] Overall, both mineral oil and PAO oil are rejected due to significant swelling of EPDM, and PDMS is rejected due to both significant swelling and significant immersion of silicone rubber.

[0138] Table 3 provides the characterization results for Samples 1 through 22. To receive an overall pass, the samples must pass all characterization requirements:

[0139] ㆍ Fluid at 25℃ = Example

[0140] ㆍ Viscosity at 25℃ = <100 mm 2 / s

[0141] ㆍ Flash point > 150℃

[0142] ㆍ SiH residue < 10 ppm

[0143] ㆍ Hydrocarbon residue < 20 wt%

[0144] ㆍ Compatibility test = Passed for both silicone rubber and EPDM rubber.

[0145] The following samples are rejected in their entirety:

[0146] Sample 6: This sample is wax at 25°C, which proves that the R group in chemical structure (I) must contain fewer than 18 carbon atoms.

[0147] Sample 7: This sample proves that m must be less than 22.

[0148] Samples 13 to 16: These samples demonstrate that when the sum of subscripts m and n (i.e., "m+n") exceeds 54, the viscosity becomes too high.

[0149] Samples 20 to 22: These samples demonstrate the requirement that m be greater than 0.

[0150] [Table 3]

[0151]

Claims

Claim 1 A process comprising the step of immersing a device in a cooling fluid, wherein the cooling fluid comprises an alkyl modified silicone oil having the following average chemical structure (I): (CH3)3SiO-[(CH3)2SiO] m -[R(CH3)SiO] n -Si(CH3)3(I) In the above formula, R is independently selected from the group consisting of alkyl and substituted alkyl groups in each case, and each R group has 6 or more and simultaneously 17 or fewer carbon atoms; the subscript m has a value of 1 or more and simultaneously less than 22, the subscript n has a value of 1 or more, the sum of m+n is greater than 5 and simultaneously less than 50, and the cooling fluid is a liquid at 25°C and a pressure of 101 kilopascals (kPa); 100 mm at 25°C 2 A process having a kinematic viscosity of less than / s; without significantly swelling or impregnating EPDM or silicone rubber; having a flash point greater than 150°C; and may be halogen-free, wherein the alkyl modified silicone oil has a SiH concentration in which the hydrogen for the SiH group is less than 10 ppm based on the weight of the alkylmethylsiloxane and the free hydrocarbon concentration is less than 20 wt% based on the weight of the alkylmethylsiloxane. Claim 2 In paragraph 1, the device is a heat generating device and / or a heat sink attached to the heat generating device, a process. Claim 3 A process according to claim 1 or 2, wherein the R group in structure (I) is an alkyl or a phenyl-substituted alkyl. Claim 4 A process according to claim 1 or 2, wherein the cooling fluid comprises less than 20 weight percent of hydrocarbons based on the weight of the cooling fluid. Claim 5 A process according to claim 1 or 2, further comprising a step of cooling a cooling fluid. Claim 6 In paragraph 5, the process in which the cooling fluid circulates around the device during the cycle, passes through a cooling unit, and then returns to the device. Claim 7 A liquid immersion cooling system comprising a device in a cooling fluid, wherein the cooling fluid comprises an alkyl modified silicone oil having the following average chemical structure (I): (CH3)3SiO-[(CH3)2SiO] m -[R(CH3)SiO] n -Si(CH3)3(I) In the above formula, R is independently selected from the group consisting of alkyl and substituted alkyl groups in each case, and each R group has 6 or more and simultaneously 17 or fewer carbon atoms; the subscript m has a value of 1 or more and simultaneously less than 22, the subscript n has a value of 1 or more, the sum of m+n is greater than 5 and simultaneously less than 50, and the cooling fluid is a liquid at 25°C and a pressure of 101 kilopascals (kPa); 100 mm at 25°C 2 A liquid immersion cooling system having a kinematic viscosity of less than / s; not significantly swelling or immersing EPDM or silicone rubber; having a flash point greater than 150°C; and may be halogen-free, wherein the alkyl modified silicone oil has a SiH concentration in which the hydrogen for the SiH group is less than 10 ppm based on the weight of the alkylmethylsiloxane and the free hydrocarbon concentration is less than 20 wt% based on the weight of the alkylmethylsiloxane. Claim 8 In paragraph 7, the device is a liquid immersion cooling system, which is a heat generating device and / or a heat sink attached to the heat generating device. Claim 9 A liquid immersion cooling system according to claim 7 or 8, further comprising a cooler for removing heat from a cooling fluid. Claim 10 A liquid immersion cooling system according to claim 7 or 8, further comprising a circulation component that allows the cooling fluid to flow around a device immersed in the cooling fluid.

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