Cooling liquid for radar system as well as preparation method and application of cooling liquid

Abstract

The invention belongs to the technical field of radar system cooling and discloses cooling liquid for a radar system as well as a preparation method and application of the cooling liquid. The cooling liquid comprises base oil and an additive, and the base oil comprises 80-100 wt% of paraffin-based mineral oil and 0-20 wt% of naphthenic mineral oil based on the total weight of the base oil; the weight-average molecular weight of the paraffin-based mineral oil is 250-300 g / mol, and the weight-average molecular weight of the naphthenic mineral oil is 260-320 g / mol. The cooling liquid has the advantages of being excellent in high and low temperature tolerance, high in oxidation stability, good in electrical insulation performance, good in heat transfer performance, good in material compatibility and environmentally friendly, can be used for effective cooling of a radar system and corrosion protection of multi-metal materials and welding flux in the radar liquid cooling system, and is long in service life and suitable for industrial production.

Description

Technical Field

[0001] This invention belongs to the field of radar system cooling technology, and specifically relates to a coolant for radar systems, its preparation method, and its application. Background Technology

[0002] Liquid cooling is becoming the primary method for heat dissipation in radar systems, which is crucial for ensuring the stability and safety of radar equipment under various environmental conditions.

[0003] Alcohol solutions are currently the most commonly used cooling media for radar equipment due to their low freezing point, low corrosiveness, high specific heat capacity, and good fluidity. For example, Chinese patent CN112226213A discloses a low-conductivity dielectric coolant for ethylene glycol-based phased array radar, made from the following raw materials in parts by weight: 66-68 parts ethylene glycol; 32-34 parts deionized water; 2.0-4.5 parts organic nonionic composite corrosion inhibitor; 0.08-0.16 parts organic nonionic rubber protectant; 0.01-0.02 parts scale inhibitor; and 0.002-0.003 parts defoamer. This coolant has low conductivity, providing corrosion protection for multi-metal materials and solders in liquid cooling systems such as radar, exhibiting good compatibility with non-metals, and a long service life. Chinese patent CN109762533A discloses a multi-effect, low-foaming organic radar coolant, made from the following raw materials in parts by weight: 44-95 parts ethylene glycol; 5-56 parts deionized water; 1.0-4.5 parts organic composite corrosion inhibitor; 0.1-0.5 parts pH buffer; 0.08-0.16 parts rubber protectant; 0.01-0.02 parts scale inhibitor; 0.00023-0.00028 parts colorant; and 0.002-0.003 parts defoamer. This coolant produces minimal foam, providing corrosion protection for multi-metallic materials and solders in liquid cooling systems such as radar systems. It also exhibits good compatibility with non-metallic materials and a long service life.

[0004] However, alcohol solutions used as cooling media oxidize under high-temperature operating conditions to form corrosive mixed acids, which are more corrosive than tap water without coolant. Furthermore, the low-temperature resistance of currently reported radar coolants still cannot meet the cooling requirements of radars under extreme low-temperature conditions.

[0005] Therefore, it is imperative to develop a coolant with excellent comprehensive performance that meets the requirements of radar systems in terms of high and low temperature tolerance, heat transfer, safety, electrical insulation, material compatibility, and environmental friendliness. Summary of the Invention

[0006] In view of the shortcomings of the prior art, the present invention provides a coolant for radar systems, its preparation method, and its application. This coolant possesses excellent high and low temperature tolerance, high oxidation stability, good electrical insulation properties, good heat transfer properties, good material compatibility, and is environmentally friendly. It can be used for effective cooling of radar systems, as well as corrosion protection of multi-metal materials and solders in radar liquid cooling systems. It has a long service life, a simple preparation method, and is suitable for industrial production.

[0007] In a first aspect, the present invention provides a coolant for a radar system, comprising a base oil and additives; the base oil comprises 80-100% by weight of paraffinic mineral oil and 0-20% by weight of naphthenic mineral oil, based on the total weight of the base oil; the paraffinic mineral oil has a weight-average molecular weight of 250-300 g / mol, and the naphthenic mineral oil has a weight-average molecular weight of 260-320 g / mol.

[0008] In some implementations, the kinematic viscosity of the paraffinic mineral oil at -40°C is less than 1500 mmHg. 2 / s.

[0009] In some implementations, the pour point of the paraffinic mineral oil is less than -65°C.

[0010] In some implementations, the kinematic viscosity of the naphthenic mineral oil at -40°C is less than 2500 mm. 2 / s.

[0011] In some implementations, the pour point of the naphthenic mineral oil is less than -65°C.

[0012] On the one hand, if the weight-average molecular weight of the mineral oil is too high, the kinematic viscosity of the coolant at -40°C will be higher, and the pour point will also be higher. On the other hand, if the kinematic viscosity of the mineral oil at -40°C is too low, the flash point of the coolant will be low, making it less resistant to high temperatures and posing a significant risk to the safety of the coolant. If the kinematic viscosity at -40°C is too high, the low-temperature viscosity of the coolant will be high in low-temperature regions, making it difficult to pump the coolant during system startup. By using paraffinic mineral oil and naphthenic mineral oil with the above-defined weight-average molecular weights as raw materials and making appropriate weight ratios, it is possible to obtain a lower pour point and a higher flash point while ensuring good pumpability of the coolant.

[0013] In some implementation schemes, the mass ratio of base oil to additive is 100:0.1 to 1.0.

[0014] In some embodiments, the additives are antioxidants and / or light stabilizers, both of which are commercially available, and this invention does not impose any restrictions on the manufacturers of the additives. The additives can further improve the performance of the coolant. For example, antioxidants can improve thermal oxidation stability, and light stabilizers can reduce the discoloration of the coolant when exposed to light.

[0015] In some embodiments, the antioxidant is a phenolic antioxidant and / or an amine antioxidant, including but not limited to one or more combinations of 2,6-di-tert-butyl-p-cresol, 4,4-methylenebis(2,6-di-tert-butylphenol), phenyl-α-naphthylamine, and alkyl diphenylamine.

[0016] In some implementations, the light stabilizer is selected from one or more combinations of benzophenones, salicylic acids, benzotriazoles, and hindered amine derivatives.

[0017] In some implementation schemes, considering factors such as effectiveness and economy, the amount of antioxidant added is 0.1 to 0.8% by weight of the total base oil.

[0018] In some implementation schemes, considering factors such as effectiveness and economy, the amount of light stabilizer added is 0.01 to 0.1% by weight, based on the total weight of the base oil.

[0019] Secondly, the present invention provides a method for preparing the aforementioned coolant for radar systems, comprising: mixing paraffin-based mineral oil and naphthenic mineral oil, heating to 60-80°C, then adding additives and stirring.

[0020] Thirdly, the present invention provides an application of the aforementioned coolant in cooling radar systems under low-temperature environments.

[0021] The beneficial effects of this invention are as follows:

[0022] The coolant provided by this invention, by using paraffin-based mineral oil and naphthenic mineral oil of specific molecular weights in a suitable weight ratio, greatly improves the high and low temperature resistance of the coolant (kinematic viscosity less than 1500 mmHg at -40℃). 2 With a flash point greater than 160℃ and a pour point less than -66℃, it is suitable for direct immersion cooling of radar systems. It also features high oxidation stability (rotating oxygen bomb (140℃) greater than 510 min), good electrical insulation (breakdown voltage 56~65kV), good thermal transfer performance (thermal conductivity (25℃) greater than 0.12W / m·k, specific heat (25℃) greater than 2.0J / g·k), good material compatibility, and is environmentally friendly (biodegradability greater than 60%). Detailed Implementation

[0023] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below. 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 skilled in the art without creative effort are within the scope of protection of the present invention.

[0024] The paraffinic mineral oils used in Examples 1-5 below have a weight-average molecular weight of 250-300 g / mol and a kinematic viscosity of 1000-1500 mmHg at -40°C. 2 / s, pour point -67 to -69℃. The weight-average molecular weight of naphthenic mineral oil is 260–320 g / mol, and its kinematic viscosity at -40℃ is 1800–2500 mm³ / s. 2 / s, pour point is -67 to -69℃.

[0025] The paraffinic mineral oils used in the following examples have a weight-average molecular weight of 250–300 g / mol and a kinematic viscosity of 1000–1500 mmHg at -40°C. 2 / s, pour point -67 to -69℃. The weight-average molecular weight of naphthenic mineral oil is 260–320 g / mol, and its kinematic viscosity at -40℃ is 1800–2500 mm³ / s. 2 / s, pour point -67~-69℃. Both paraffinic mineral oil and naphthenic mineral oil are produced and sold by PetroChina Karamay Petrochemical Co., Ltd. Paraffinic mineral oil is obtained by first distilling paraffinic crude oil under atmospheric and vacuum pressure to obtain a 280~360℃ fraction, and then using a "hydrogenation treatment—isomerization dewaxing—supplementary refining" process. Naphthenic mineral oil is obtained by first distilling naphthenic crude oil under atmospheric and vacuum pressure to obtain a 280~350℃ fraction, and then using a "hydrogenation treatment—hydrogenation dewaxing—supplementary refining—precision fractionation" process.

[0026] Examples 1-5

[0027] Naphthenic mineral oil and paraffinic mineral oil are mixed according to the formula and dosage in Table 1, heated to 70°C, and stirred evenly to obtain base oil; antioxidant and light stabilizer are added to the base oil in sequence, and then stirred evenly to obtain coolant for radar system.

[0028] Table 1 Formula

[0029]

[0030]

[0031] The performance of the coolant used in the radar system prepared in Examples 1 to 5 was tested, and the test results are shown in Tables 2 and 3.

[0032] Table 2 Performance test results of each indicator

[0033]

[0034] Table 3. Material compatibility test results

[0035]

[0036]

[0037] The results above show that the kinematic viscosity of the coolants prepared in Examples 1-5 at -40°C is 1256-1487 mm⁻¹. 2 The coolant exhibits excellent high and low temperature resistance, high oxidation stability, good electrical insulation, good heat transfer performance, good material compatibility, and is environmentally friendly. It meets the cooling requirements of radar systems. Furthermore, the coolant does not contain synthetic oils, is low in cost, and has a simple preparation method suitable for industrial production.

[0038] The preferred embodiments of the present invention have been described in detail above. However, the present invention is not limited to the specific details in the above embodiments. Within the scope of the technical concept of the present invention, various simple modifications can be made to the technical solution of the present invention, and these simple modifications all fall within the protection scope of the present invention.

Claims

1. A coolant for a radar system, characterized in that, The coolant used in the radar system contains base oil and additives; The base oil comprises 80-100% by weight of paraffinic mineral oil and 0-20% by weight of naphthenic mineral oil, based on the total weight of the base oil; the weight-average molecular weight of the paraffinic mineral oil is 250-300 g / mol, and the weight-average molecular weight of the naphthenic mineral oil is 260-320 g / mol.

2. The coolant for a radar system according to claim 1, characterized in that, The paraffinic mineral oil has a kinematic viscosity of less than 1500 mmHg at -40°C. 2 / s.

3. The coolant for a radar system according to claim 1, characterized in that, The paraffinic mineral oil has a pour point of less than -65°C.

4. The coolant for a radar system according to claim 1, characterized in that, The kinematic viscosity of the naphthenic mineral oil at -40°C is less than 2500 mm. 2 / s.

5. The coolant for a radar system according to claim 1, characterized in that, The pour point of the cycloalkyl mineral oil is less than -65°C.

6. The coolant for a radar system according to claim 1, characterized in that, The mass ratio of the base oil to the additive is 100:0.1 to 1.

0.

7. The coolant for a radar system according to claim 1, characterized in that, The additive is an antioxidant and / or a light stabilizer.

8. The coolant for a radar system according to claim 7, characterized in that, The antioxidant is a phenolic antioxidant and / or an amine antioxidant; and / or, the light stabilizer is selected from one or more combinations of benzophenones, salicylic acid, benzotriazoles, and hindered amine derivatives.

9. A method for preparing a coolant for a radar system according to any one of claims 1 to 8, characterized in that, The preparation method includes: mixing paraffin-based mineral oil and naphthenic mineral oil, heating to 60-80°C, then adding additives and stirring.

10. The application of the coolant according to any one of claims 1 to 8 in cooling radar systems in low-temperature environments.

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