New method for realizing heat flow control based on negative differential thermal resistance effect

Abstract

The invention relates to a new method for realizing heat flow control based on a negative differential thermal resistance effect, and belongs to the technical field of heat flow control. A left-side solid of a system adopted by the method is a constant-temperature heating end, a right-side solid is a heating end, and composite fluid for controlling heat flow is arranged between the constant-temperature heating end and the heating end; according to the control method, the temperature of the constant-temperature heating end of the system is constant, different temperature differences are controlled by reducing the temperature of the heating end, and heat flow control is achieved; or the heat flow is controlled by adjusting the density of the composite fluid. The method is a novel method capable of realizing heat flow control in a solid-liquid system, and can realize heat flow regulation and control in a larger temperature range and amplitude.

Description

Technical Field

[0001] This invention belongs to the field of heat flow control technology, specifically relating to a new method for heat flow control based on the negative differential thermal resistance effect. Background Technology

[0002] According to Fourier's law of heat conduction, that is... q = ΔT / R ,in q For heat flux density, ΔT and R Let represent the system temperature difference and thermal resistance, respectively. The temperature difference acts as the driving force for heat transfer; a larger temperature difference results in a larger heat flow, a general conclusion based on linear response theory. If the heat flow decreases as the temperature difference increases, this is called the "negative differential thermal resistance effect." The negative differential thermal resistance effect causes the system's thermal conductivity to exhibit a non-linear response to changes in external temperature, playing an indispensable role in heat flow control. If a system exhibits a negative differential thermal resistance effect, then the heat transfer process can be controlled based on this system, leading to the design of thermal devices such as thermal diodes, thermal transistors, and thermal logic gates. The negative differential thermal resistance effect has important applications in many fields, including thermal management, thermal protection, energy storage, and thermal computing.

[0003] However, most current research on heat control is based on solid-state systems, with limited research on solid-liquid systems. In fact, liquid cooling, as one of the most effective heat dissipation methods, involves solid-liquid interface heat transfer in practical applications, such as effective heat dissipation of electronic components, industrial heat recovery, aerospace propulsion, marine machinery, and biochemical engineering. Therefore, achieving precise control of heat transfer in solid-liquid systems has significant practical implications.

[0004] The negative differential thermal resistance (NDR) effect was initially proposed in lattice systems, such as low-dimensional lattices, carbon nanotubes, graphene nanoribbons, and hexagonal boron nitride heterostructures. However, the main drawback of the NDR effect in solid-state lattice systems is the difficulty in fabrication and limited manufacturing conditions, which restricts its practical applications. Recently, in solid-gas-solid systems, the NDR effect can be achieved by increasing the temperature difference by lowering the temperature at the low-temperature end while maintaining the temperature at the high-temperature end. As the temperature difference increases, gas molecules can adsorb onto the solid surface at the low-temperature end, leading to an increase in the total thermal resistance of the system, thus realizing the NDR effect. In solid-liquid-solid systems, the NDR effect can also be achieved by increasing the total thermal resistance of the system due to molecular adsorption. Solid-liquid-solid systems are easy to manufacture and can play a good role in practical applications. At the same time, solid-liquid-solid systems offer greater operational flexibility and more options.

[0005] Current research on the negative differential effect in solid-liquid systems is still immature, and the controllable amplitude and range are limited, which restricts the control of the system's heat flow.

[0006] Many thermal control systems have been developed, but current thermal control systems do not respond directly to temperature changes. Instead, they require a temperature acquisition device to collect temperature information and then a thermal controller to adjust various parts of the thermal process. This reduces heat flow by decreasing the temperature difference, which means that if you want to reduce heat flow, you inevitably need to reduce the temperature difference. However, by using the negative differential thermal resistance effect to control heat flow, this process of reducing the temperature difference can be avoided.

[0007] The scheme of controlling heat flow using the negative differential thermal resistance effect relies on the tightness of the contact between pipes. Therefore, although the heat flow can be reduced by increasing the thermal resistance by decreasing the tightness of the contact between pipes, this scheme requires that the heat transport pipes be made of materials with a negative coefficient of thermal expansion. The coefficient of thermal expansion of the pipe material directly affects the control of heat flow. Therefore, heat control under different conditions can only be achieved by changing the coefficient of thermal expansion of the pipe support material. The control method is singular and cannot be applied to a variety of working conditions.

[0008] Based on this, the present invention proposes a new method for heat flow control in solid-liquid systems, which can achieve heat flow regulation over a wider temperature range and amplitude, and is more flexible in control than existing technologies, and can be applied to different working conditions. Summary of the Invention

[0009] The purpose of this invention is to provide a new method for heat flow control based on the negative differential thermal resistance effect. This method is a novel approach to heat flow control in solid-liquid systems, enabling heat flow regulation over a wider temperature range and amplitude. It offers diverse control methods and can be applied to various operating conditions.

[0010] To achieve the above objectives, the technical solution adopted by the present invention is as follows: A novel method for heat flow control based on the negative differential thermal resistance effect, wherein the solid on the left side of the system is a constant-temperature heating end, the solid on the right side is a heating end, and a composite fluid for controlling heat flow is located between the constant-temperature heating end and the heating end; The method ensures that the temperature of the heating end of the system remains constant, and heat flow control is achieved by reducing the temperature of the heating end and controlling different temperature differences. Alternatively, heat flow can be controlled by altering the nanostructure morphology of the solid surface at the heating end; Alternatively, heat flow can be controlled by adjusting the density of the composite fluid; The above methods, used individually or in combination, can achieve intelligent heat flow control in multiple modes and over a wide range.

[0011] Furthermore, the surface of the constant-temperature heating end has a planar structure, and the surface of the heating end has a nanostructure with an adjustable morphology.

[0012] Furthermore, the tunable nanostructure can be an active ribbed nanostructure, a dynamically adjustable nanopillar array, a dynamically adjustable nanogroove structure, a deformable nanofilm structure, a checkerboard nanostructure, or a solid wall with high roughness, to adapt to different fluid densities and temperature conditions.

[0013] In this invention, the active ribbed nanostructure material includes, but is not limited to, one of the following: conductive polymer PEDOT:PSS, carbon nanotube (CNT) arrays, graphene films, dielectric elastomers (DE), and piezoelectric materials. The structure is an electrostatically driven "nano-venetian blind" or an electrothermally driven "nano-actuator." As a specific embodiment, the active ribbed nanostructure uses a VA-CNT array as the ribs, with parameters: rib height H = 1 μm, rib spacing P = 2 μm, and rib width W = 20 nm (diameter of a single CNT). The entire array can be considered as a single "rib." Performance: Under a voltage of 10-20 V, a significant lateral deflection can be observed at the top of the entire CNT array. As another specific embodiment, the active ribbed nanostructure uses a single layer of graphene as the driving layer and SU-8 polymer as the passive layer, with parameters: total rib thickness H = 500 nm, where the polymer layer accounts for the majority; rib length = 20 μm; and rib width = 5 μm. Performance: At 3-5 V, it can generate bending displacement of several micrometers in milliseconds to seconds, corresponding to angle changes of tens of degrees.

[0014] In this invention, the dynamically adjustable nanogroove structure material includes, but is not limited to, silicon, glass, and metal. As a specific embodiment, the groove structure consists of a parallel array of nanogrooves etched onto the surface of a heat source. The bottom of the groove is a silicon metal electrode, covered with a thin dielectric layer of SiO2 (0.5 nm) and a hydrophobic layer of Teflon. The groove width is 0.8 nm, the groove depth can be 0.4 nm, 0.8 nm, 1.2 nm, or 1.6 nm, and the groove spacing is 0.8 nm.

[0015] The aforementioned nanostructure morphology (such as height, spacing, and hydrophobicity) can dynamically change according to external stimuli (such as electric field and temperature field), thereby actively regulating the adsorption and condensation behavior of fluids at the interface, significantly enhancing the adjustability of thermal resistance and adaptability to operating conditions.

[0016] The nanostructures described above in this invention are prepared using photolithography or self-assembly techniques, which are existing technologies.

[0017] Furthermore, the composite fluid is a mixture of 95 vol% concentration of single-atom gaseous argon and 5 vol% of modified gaseous argon (the contact angle between the modified gaseous argon and the solid is 50°); or a sodium dodecyl sulfate aqueous solution with a concentration of 1.5 wt%-5 wt%; or a polyethylene glycol aqueous solution with a mass fraction of 10%-40%; or a mixture of 0.1 vol%-0.5 vol% carbon-based nanofluid and 0.05 wt%-0.08 wt% dispersant, wherein the carbon-based nanofluid includes, but is not limited to, one of carbon nanotubes, graphene, and graphene oxide nanofluids, and the dispersant is sodium dodecylbenzenesulfonate.

[0018] The composite fluid is a mixture of 95 vol% concentration of monatomic gaseous argon and 5 vol% modified gaseous argon (the contact angle between the modified gaseous argon and the solid is 50°). The modified gaseous argon has a contact angle of 50° with the solid to prepare a hybrid self-assembled monomolecular film on a metal gold substrate. The film is composed of thiol molecules with two different terminal groups in a specific ratio, so that the final surface interaction energy with argon is equivalent to a contact angle of 50°.

[0019] The principle behind heat flow control using composite fluids lies in the fact that 95 vol% monatomic argon is the main gas. The heat conduction of monatomic gases is primarily achieved through collisions (kinetic energy transfer) between atoms. Its thermal conductivity is related to temperature and pressure, but it does not inherently possess "on / off" or "variable" characteristics. 5 vol% modified argon is the key functional component. Through physical or chemical methods, its surface properties are altered to achieve a "50° contact angle with the solid." By observing the adsorption / desorption behavior of the modified gas component on the solid surface, the thermal boundary resistance between the solid and the main gas is dynamically changed, thereby achieving control of the heat flow path.

[0020] Sodium dodecyl sulfate (SDBS), a typical anionic surfactant, can effectively reduce interfacial tension, promote bubble formation and liquid spreading, and decrease the critical micelle concentration as the temperature difference increases within the range of 20-60℃. Further temperature increases lead to micelle formation, which act as "micro-stirring" agents in the solution, enhancing internal mixing and heat transfer. However, further temperature increases, especially near the cloud point, increase the number of micelle aggregates, altering solution properties, disrupting micelle stability, increasing surface tension, decreasing wettability, and weakening the heat transfer enhancement effect. Combining carbon-based nanofluids (such as carbon nanotubes, graphene, and graphene oxide nanofluids) with dispersants (such as sodium dodecylbenzenesulfonate (SDBS), for example, using 0.1 vol% carbon nanotubes (CNTs) and graphene, results in a rapid linear increase in the thermal conductivity of the nanofluid with increasing temperature, without significant attenuation at high temperatures. This is because the phonon thermal conductivity of carbon materials is more active at high temperatures, while the interfacial thermal resistance between the particles and the base liquid decreases significantly with increasing temperature. As the temperature rises further, the high temperature causes the dispersant (sodium dodecylbenzenesulfonate SDBS, concentration 0.05wt%) to become ineffective, and the carbon-based particles agglomerate severely, forming a thermal resistance barrier; at the same time, it also causes the particle-base liquid interface layer to become disordered, and the interfacial thermal resistance increases in the opposite direction.

[0021] Furthermore, the composite fluid is placed in a channel made of a highly thermally conductive solid (such as gold, silver, copper, or silicon).

[0022] Furthermore, the system is applied in thermal transistors, temperature-adaptive heat sinks, thermal switches, thermal logic gates, thermal transistors, thermal computers, and thermal storage devices.

[0023] Compared with the prior art, the beneficial effects of the present invention are as follows: 1. Compared with current technologies, this system uses the negative differential thermal resistance effect to control heat flow, and the heat flow can be reduced by increasing the temperature difference. The system can also control the strength of the negative differential thermal resistance effect by adjusting the fluid density in the interlayer, the surface structure of the solid end, the injection volume, and the injection method. Furthermore, it does not require specific temperature expansion characteristics of the pipe manufacturing material, allowing for more flexible pipe material selection, and more flexible control range and adjustment range, making it applicable to various working conditions.

[0024] 2. This invention creatively combines solid-liquid interface science with heat transfer, and through a multi-synergistic regulation mechanism of "fluid components + nanostructures", it achieves active and flexible control of the intensity and trigger threshold of the negative differential thermal resistance effect, solving the problems of existing technologies having single regulation methods and relying on special materials.

[0025] 3. This invention can achieve the regulation of heat in liquid systems, and the regulation amplitude and range are significantly enhanced, providing a core technological foundation for the development of a new generation of intelligent thermal management devices. Attached Figure Description

[0026] Figure 1 This is a schematic diagram of the device structure for heat flow control using the negative differential thermal resistance effect according to the present invention. Figure 2 This is a graph showing the relationship between fluid heat flow and temperature difference in this invention; Figure 3 This is a graph showing the relationship between fluid heat flow rate and fluid density in this invention; Figure 4 The relationship between negative differential thermal resistance and the morphology of nanostructures on the solid surface at the heating end; Figure 5 The morphology of the solid surface at the heating end is a nanostructure. In the diagram, 1-constant temperature heating end, 2-fluid, 3-heating end. Detailed Implementation

[0027] The technical solution and effects of the present invention will be further described below with reference to the accompanying drawings and specific embodiments, but the scope of protection of the present invention is not limited thereto.

[0028] This invention provides a novel method for heat flux control based on the negative differential thermal resistance effect. This method is a new approach to heat flux control in solid-liquid systems, enabling heat flux regulation over a wider temperature range and amplitude. The negative differential thermal resistance effect is a heat transfer phenomenon where heat flux gradually decreases as temperature increases.

[0029] A scheme for heat flow control using the negative differential thermal resistance effect has been proposed. This scheme is a negative differential thermal conduction device based on interfacial thermal resistance, including a heating end and a heated end, with a pipe made of a material with a negative coefficient of thermal expansion in between. The pipes have good contact at the interface and also have a certain mutual compression effect. Under normal conditions, the heat transport channel is open. However, when the temperature difference between the heating end and the heated end increases, the volume of the pipe made of the negative coefficient of thermal expansion material will shrink, the pressure at the interface will decrease, and the interfacial thermal resistance will increase rapidly, causing the negative differential thermal resistance effect, which leads to a decrease in heat flow. When the temperature difference between the two ends continues to increase to the temperature threshold, the heat transport channel will gradually close.

[0030] However, this scheme requires that the heat transport pipeline be made of a material with a negative coefficient of thermal expansion. The coefficient of thermal expansion of the pipeline material directly affects the control of heat flow. Therefore, thermal control under different conditions can only be achieved by changing the coefficient of thermal expansion of the pipeline support material. The control method is singular and cannot be applied to a variety of working conditions. Example 1

[0031] To address the problems existing in the prior art, this embodiment provides a new method for heat flow control based on the negative differential thermal resistance effect.

[0032] The system used in this embodiment is a solid-liquid sandwich structure, such as Figure 1 As shown, the solid on the left side of the system is the constant temperature heating end 1, and the solid on the right side is the heating end 3. Between the constant temperature heating end 1 and the heating end 3 is a composite fluid 2 that controls the heat flow. In this embodiment, the constant temperature heating end 1 and the heating end 3 are gold plates with smooth surfaces and dimensions of 5nm×3.5nm×1nm. The temperature of the constant temperature heating end 1 of the system is constant, and different temperature differences are controlled by lowering the temperature of the heating end 3.

[0033] In this embodiment, the heat transport channel consists of solid Au (a hybrid self-assembled monolayer film is prepared on the surface of solid Au, with a contact angle of 50° with argon gas) and gaseous Ar. It is placed in close contact and fixed between isothermal heating end 1 and heating end 3. The temperature of the cooling section is maintained at 300K, while the temperature of heating end 3 is gradually changed from 275K to 50K. The relationship between steady-state heat flux J and the temperature difference between isothermal heating end 1 and heating end 3 is measured, and the results are as follows: Figure 2 As shown by the red line segment, the heat flux reaches its maximum at a temperature difference of 150K, indicating the occurrence of negative differential thermal resistance. This characteristic provides a new approach for controlling heat flux under characteristic temperature differences, enabling intelligent control of heat flux by utilizing its own thermal transport properties.

[0034] Under normal conditions, the heat transport channel is open. However, when the temperature difference between the constant-temperature heating end 1 and the heating end 3 increases, a large number of fluid molecules in the pipe are adsorbed at the low-temperature interface. The fluid temperature decreases, and condensation occurs at the low-temperature interface, resulting in a vacuum between the fluid and the high-temperature end. This causes a rapid increase in the thermal resistance at the high-temperature end interface, leading to a negative differential thermal resistance effect and a decrease in heat flow. When the temperature difference between the two ends continues to increase to the temperature threshold, the heat transport channel will gradually close. Please indicate the locations represented by the terms "cooling section" and "high-temperature end" in the attached diagram.

[0035] This embodiment controls the heat flow by manipulating the temperatures on both sides of the solid in the system to change the temperature difference. The control results are as follows: Figure 2 As shown. Figure 2 As shown, when the temperature difference between the solids on the left and right sides begins to increase, the heat flow of the intermediate fluid medium is directly proportional to the temperature difference. However, when the maximum heat flow is reached, the heat flow becomes inversely proportional to the temperature difference. This is the negative differential thermal resistance effect. Furthermore, when the temperature difference reaches a certain value, the heat flow will return to zero. This phenomenon can be used to adjust the magnitude of the heat flow or even switch it on and off. Moreover, the heat flow can be more flexibly controlled by adjusting the density of the intermediate fluid. When the fluid density increases, the maximum heat flow that achieves the negative differential thermal resistance will increase, and the temperature difference at which the negative differential thermal resistance phenomenon occurs will also increase, allowing for more flexible control of the heat flow in the system.

[0036] In this embodiment, the specific process of preparing a hybrid self-assembled monolayer on a solid Au surface, with a contact angle of 50° with argon gas, is as follows: Step 1: Substrate Pretreatment Cleaning: The gold substrate was ultrasonically cleaned in acetone and ethanol for 15 minutes each to remove organic contaminants. Drying: Gently blow dry the surface with high-purity nitrogen gas; Plasma activation: The gold substrate is placed in a plasma cleaner and treated with oxygen or air plasma at 100W power for 2-5 minutes. This step can thoroughly clean the surface and greatly improve its hydrophilicity, making the gold surface reach an "ultra-clean" state with a contact angle close to 0°, laying the foundation for subsequent uniform self-assembly. Step 2: Prepare the mixed thiol solution Preparation of stock solutions: Prepare 50 mL each of a 1.0 mM pure OH-terminated thiol ethanol solution and a pure CH3-terminated thiol ethanol solution; Preparation of the target mixed solution: By changing the molar fraction of the two molecules, the surface properties are controlled, and a mixed solution with a molar fraction of 0.7 for OH-terminated thiols is prepared. Calculation: Take a 100mL volumetric flask and add the following liquid using a pipette: OH-terminated thiol stock solution (1mM): 0.7 * 100 mL * 1mM / 1mM = 70 mL CH3-terminal thiol stock solution (1mM): 0.3 * 100 mL * 1mM / 1mM = 30 mL After mixing, the total solution volume is 100 mL, and the total thiol concentration remains 1 mM; ensure thorough mixing. Step 3: Self-assembly process The plasma-treated, warm gold substrate (30-40℃ helps form a more ordered film) is quickly immersed in a prepared mixed thiol solution. Leave at room temperature, away from light, for 24 hours; ensure the container is sealed to prevent solvent evaporation; After 24 hours, the sample was removed with tweezers and ultrasonically cleaned three times in anhydrous ethanol for two minutes each time to remove excess thiol molecules that were physically adsorbed. The surface was dried with high-purity nitrogen gas, and then placed in a vacuum drying oven at 50°C for 1 hour to stabilize the film. Example 2

[0037] This embodiment provides a new method for heat flow control based on the negative differential thermal resistance effect. It is the same as Embodiment 1, except that the density of the composite fluid is changed by changing the pressure.

[0038] The temperature of the isothermal heating section 1 was maintained at 300K, while the temperature of the heating end 3 was gradually changed from 275K to 25K. The relationship between the steady-state heat flux J and the temperature difference between the isothermal heating end 1 and the heating end 3 was measured, and the results are as follows: Figure 3 As shown, the heat flux reaches its maximum value under liquids of different densities, indicating the occurrence of negative differential thermal resistance. The results show that the maximum heat flux occurs at different temperature differences as the liquid density changes. Compared to Example 1, the trigger threshold and intensity of the negative differential thermal resistance effect change due to the alteration of the fluid composition, demonstrating the effectiveness of controlling heat flux through fluid composition.

[0039] This invention controls the heat flow by manipulating the temperatures on both sides of the solid in the system to change the temperature difference. The control results are as follows: Figure 2 As shown. Figure 2 As shown, when the temperature difference between the solids on the left and right sides begins to increase, the heat flow of the intermediate fluid medium is directly proportional to the temperature difference. However, when the maximum heat flow is reached, the heat flow becomes inversely proportional to the temperature difference. This is the negative differential thermal resistance effect. Furthermore, when the temperature difference reaches a certain value, the heat flow will return to zero. This phenomenon can be used to adjust the magnitude of the heat flow or even switch it on and off. Moreover, the heat flow can be more flexibly controlled by adjusting the density of the intermediate fluid. When the fluid density increases, the maximum heat flow that achieves the negative differential thermal resistance will increase, and the temperature difference at which the negative differential thermal resistance phenomenon occurs will also increase, allowing for more flexible control of the heat flow in the system. Example 3

[0040] This embodiment is the same as Embodiment 1, except that the nanostructured surface is applied to the solid surface on the right, and the structure of the nanostructured surface is changed to adapt to different working conditions. In this embodiment, the heating end 3 is a dynamically adjustable nanogroove structure made of silicon. The groove structure is formed by etching a parallel array of nanogrooves on the heat source surface. The bottom of the groove is a silicon metal electrode, covered with a thin dielectric layer of SiO2 (0.5 nm) and a hydrophobic layer of Teflon. The groove width is 0.8 nm, the groove depth can be 0.4 nm, 0.8 nm, 1.2 nm, or 1.6 nm, and the groove spacing is 0.8 nm.

[0041] By changing the morphology of the nanostructure on the solid surface on the right, such as Figure 5 As shown, different negative differential thermal resistance phenomena can be observed, such as Figure 4 As shown, H0-H4 represent different groove depths in the nanostructure, H0 is a smooth surface, and H1, H2, H3, and H4 are nanostructure surfaces with groove depths of 0.4 nm, 0.8 nm, 1.2 nm, and 1.6 nm, respectively. Figure 4 and 5As shown, with the increase of the depth of the nanogroove, the maximum heat flow to achieve the negative differential thermal resistance effect will increase, and the maximum temperature difference can also increase. Example 4

[0042] Building upon Example 1, while maintaining a constant temperature difference (between isothermal heating end 1 and heating end 3), the molecular alignment of the composite fluid and its heat transfer between the composite fluid and the solid wall can be controlled by applying positive and negative electric fields (0.1-0.5 V / nm) or magnetic fields of a certain intensity to the solid walls on both sides. This dynamically changes the range and intensity of the negative differential thermal resistance, thereby achieving intelligent control of heat transfer within a fixed temperature range. This approach combines electrical and thermal control, significantly expanding its application scenarios.

[0043] In summary, by controlling the fluid density and nanostructure within the sandwich structure, more flexible control of heat flow can be achieved.

[0044] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A novel method for heat flow control based on the negative differential thermal resistance effect, characterized in that, The method uses a system where the solid on the left is the constant-temperature heating end, the solid on the right is the heating end, and a composite fluid that controls the heat flow is located between the constant-temperature heating end and the heating end. The method ensures that the temperature of the heating end of the system remains constant, and heat flow control is achieved by reducing the temperature of the heating end and controlling different temperature differences. Alternatively, heat flow can be controlled by altering the nanostructure morphology of the solid surface at the heating end; Alternatively, heat flow can be controlled by adjusting the density of the composite fluid; The above methods, used individually or in combination, can achieve intelligent heat flow control in multiple modes and over a wide range.

2. The method according to claim 1, characterized in that, The surface of the constant-temperature heating end has a planar structure, while the surface of the heating end has a nanostructure with an adjustable morphology.

3. The method according to claim 2, characterized in that, The tunable nanostructure can be a movable ribbed nanostructure, a dynamically adjustable nanopillar array, a dynamically adjustable nanogroove structure, a deformable nanofilm structure, a checkerboard nanostructure, or a solid wall with high roughness, to adapt to different fluid densities and temperature conditions.

4. The method according to claim 1, characterized in that, The composite fluid is a mixture of 95 vol% single-atom gaseous argon and 5 vol% modified gaseous argon; or a sodium dodecyl sulfate aqueous solution with a concentration of 1.5 wt%-5 wt%; or a polyethylene glycol aqueous solution with a mass fraction of 10%-40%; or a mixture of 0.1 vol%-0.5 vol% carbon-based nanofluid and 0.05 wt%-0.08 wt% dispersant.

5. The method according to claim 4, characterized in that, The contact angle between the modified gaseous argon and the solid is 50°.

6. The method according to claim 4, characterized in that, Carbon-based nanofluids include, but are not limited to, one of carbon nanotubes, graphene, and graphene oxide nanofluids, with sodium dodecylbenzenesulfonate as the dispersant.

7. The method according to claim 4, characterized in that, The composite fluid is placed in a channel made of a high thermal conductivity solid.

8. The method according to claim 7, characterized in that, The high thermal conductivity solid is one of gold, silver, copper, and silicon.

9. The method according to claim 1, characterized in that, The system can be used in thermal transistors, temperature-adaptive heat sinks, thermal switches, thermal logic gates, thermal transistors, thermal computers, and thermal storage devices.

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