JP5499464B2 - Heat transport fluid, heat transport device and heat transport method - Google Patents

Description

  The present invention relates to a heat transport fluid that transfers and transports heat, a heat transport device using the heat transport fluid, and a heat transport method.

  2. Description of the Related Art Conventionally, a heat transport fluid that transfers and transports heat from a heat source to the outside is used in a device that radiates heat from a heat source such as an engine or an electronic device mounted on a vehicle. The heat transport fluid removes heat from the heat source and dissipates heat from the heat exchanger. The heat transport fluid is also used for applications that transfer heat to an object to be heated. Such a heat transport fluid is required to have higher cooling performance, that is, higher heat transport capability, in order to increase energy efficiency as equipment such as a heat exchanger.

In order to enhance the heat transport capability of the heat transport fluid, for example, in Non-Patent Document 1, only a small amount of fine particles made of copper (Cu) having a diameter of 10 nm (nanometers) or less are contained in a medium made of ethylene glycol. It has been reported that the thermal conductivity of the medium is greatly improved by the inclusion. Similarly, in Non-Patent Document 2, it is reported that the thermal conductivity of the medium is greatly improved by containing carbon nanotubes in water. Also, for example, in Patent Document 1 and Patent Document 2, It has been reported that the thermal conductivity can be improved by dispersing fine particles having high thermal conductivity in the medium.
Applied Physics Letters (Applied Physics Letters), Vol. 78, no. 6, pp. 718-720 (2001) International Journal of Heat and Mass Transfer (International Journal of Heat and Mass Transfer), vol. 49, pp. 240-250 (2006) JP-T-2004-501269 JP 2004-339461 A

In general, the heat transfer coefficient α is defined as λ is thermal conductivity, ν is kinematic viscosity, ρ is density, and Cp is specific heat.
α∞λ2 / 3ν-1 / 6ρ1 / 3Cp1 / 3 (Formula 1)
It is represented by Formula 1. Therefore, although the heat conduction is dramatically improved with a small amount of the fine particle dispersion medium, the improvement effect on the heat transfer is as small as 2/3 power. Moreover, since the viscosity of the nanofluid is increased by adding fine particles, the heat transfer coefficient α is lowered.

  Then, this invention is made | formed in view of the said problem, and it aims at providing the heat transport fluid from which a high heat transfer rate is obtained, the heat transport apparatus using the same, and the heat transport method.

In order to achieve the above object, the following technical means can be employed. The heat transport fluid according to the invention of claim 1 is a solvent comprising water , fine particles dispersed in the solvent, and a substance that changes between a solid phase and a liquid phase in a specific temperature range. And including
The fine particles are gold (Au), silver (Ag), copper (Cu), iron (Fe), nickel (Ni), silicon (Si), alumina (Al ₂ O ₃ ), magnesium oxide (MgO), copper oxide. (CuO), ferric trioxide (Fe ₂ O ₃ ), titanium oxide (TiO), particles made of carbon nanotubes,
The fine particles are composed of rod-like particles having an average length in the longitudinal direction of 1 nm to 10 μm, and include at least one kind of solid-liquid phase-changing substance ,
Solid-liquid phase change substances include paraffins having a melting point of 40 to 70 ° C., barium hydroxide octahydrate, sodium acetate trihydrate, calcium chloride hexahydrate, sodium thiosulfate pentahydrate, sulfuric acid It is one of sodium decahydrate, magnesium nitrate hexahydrate, threitol, and xylitol .

  According to the present invention, in addition to the effect of adding fine particles, the heat transport is promoted by utilizing the heat absorption and heat generation of the latent heat accompanying the solid-liquid phase change, and a heat transport fluid having a high heat transfer coefficient can be obtained. Latent heat is the total amount of thermal energy required when the phase of a substance changes, and endotherm occurs when the substance undergoes a phase transition from solid to liquid, and exotherm occurs during the opposite phase transition from liquid to solid. Occur. Thereby, the latent heat accompanying such a solid-liquid phase change can be utilized, and heat transport can be promoted.

Furthermore, according to the first aspect of the invention, the fine small particles by being composed of rod-like particles, it is possible to improve the heat transfer in the longitudinal direction of the rod-shaped fine particles.

Furthermore, according to the first aspect of the invention, the fine small particles, by the enclosing at least one substance to change the solid-liquid phase at a certain temperature range, a substance that changes the solid-liquid phase microparticles Since it exists inside, the substance can be stabilized in a solvent and changed into a solid-liquid phase.

The heat transport fluid according to the invention of claim 2 is a solvent composed of ethylene glycol or a mixture of water and ethylene glycol, fine particles dispersed in the solvent, and a solid phase state and a liquid phase state in a specific temperature range A solid-liquid phase change material between
The fine particles are gold (Au), silver (Ag), copper (Cu), iron (Fe), nickel (Ni), silicon (Si), alumina (Al ₂ O ₃ ), magnesium oxide (MgO), copper oxide. (CuO), ferric trioxide (Fe ₂ O ₃ ), titanium oxide (TiO), particles made of carbon nanotubes,
The fine particles are composed of rod-like particles having an average length in the longitudinal direction of 1 nm to 10 μm, and include at least one kind of solid-liquid phase-changing substance,
Solid-liquid phase change substances include paraffins having a melting point of 40 to 70 ° C., barium hydroxide octahydrate, sodium acetate trihydrate, calcium chloride hexahydrate, sodium thiosulfate pentahydrate, sulfuric acid It is one of sodium decahydrate, magnesium nitrate hexahydrate, threitol, and xylitol.

The heat transport fluid according to the invention of claim 3 is a solvent comprising ethylene glycol or a mixture of water and ethylene glycol, fine particles dispersed in the solvent, and a solid phase state and a liquid phase state in a specific temperature range A solid-liquid phase change material between
Fine particles are gold (Au), silver (Ag), copper (Cu), iron (Fe), nickel (Ni), silicon (Si), alumina (Al ₂ O ₃ ), Magnesium oxide (MgO), copper oxide (CuO), ferric trioxide (Fe) ₂ O ₃ ), Titanium oxide (TiO), or carbon nanotube particles,
The fine particles are composed of rod-like particles having an average length in the longitudinal direction of 1 nm to 10 μm, and include at least one kind of solid-liquid phase-changing substance,
The solid-liquid phase changing substance is any one of magnesium chloride hexahydrate, mannitol, erythritol, and sorbitol.

According to a fourth aspect of the present invention, in the heat transport fluid according to the third aspect, the fine particles are carbon nanotubes, and the solid-liquid phase change substance is erythritol.

As in the invention according to claim 5 , the heat transport fluid in each of the above inventions is a first member, a second member having a temperature lower than that of the first member, a first member, and a second member. And a circulation means for circulating the heat transport fluid so as to pass through the heat transport device.

Further, the heat transport fluid of each of the above inventions, as in the invention according to claim 6 , is a heat transport fluid that passes through the first member and the second member having a temperature lower than that of the first member. It can be used in a heat transport method that circulates and transports heat from the second member to the first member.

  According to this apparatus and method, the heat absorption and heat generation of the latent heat accompanying the solid-liquid phase change is utilized, the heat is absorbed by the first member on the high temperature side, and the heat is released by the second member on the low temperature side. Therefore, it is possible to realize heat transport that dramatically increases the heat transport amount.

  A plurality of modes for carrying out the present invention will be described below with reference to the drawings. In each embodiment, parts corresponding to the matters described in the preceding embodiment may be denoted by the same reference numerals, and redundant description may be omitted. When only a part of the configuration is described in each mode, the other modes described above can be applied to the other parts of the configuration. Not only combinations of parts that clearly show that combinations are possible in each embodiment, but also combinations of the embodiments even if they are not specified unless there is a problem with the combination. Is also possible.

  The heat transport fluid according to the present invention includes a solvent that is an aggregate of solvent molecules, fine particles dispersed in the solvent, and a substance that undergoes a solid-liquid phase change in a specific temperature range. This heat transport fluid absorbs ambient heat or releases heat to the surroundings by a substance that changes in phase between the solid state and the liquid phase, triggered by the temperature of the environment in which the heat transport fluid is used. . In this way, heat transport is promoted by utilizing the heat absorption and heat generation of the latent heat accompanying the solid-liquid phase change.

(First embodiment)
Hereinafter, a first embodiment which is an embodiment of the present invention will be described with reference to FIGS. 1 and 2. The heat transport fluid according to the present embodiment is used for cooling, for example, an in-vehicle engine or a mission. The heat transport fluid transfers and transports heat from a heat source to the outside. The solvent used for the heat transport fluid is composed of a single component such as water, and contains fine particles 1 having a higher thermal conductivity than the solvent.

  The solvent is composed of an aggregate of solvent molecules and is made of, for example, water or an organic substance (for example, ethylene glycol, toluene, etc.). The solvent can be a fluid that disperses the microparticles 1 and carries the microparticles 1. This fluid can be constituted by liquid or gas. A fluid may be composed of single or multiple components. For example, water or a liquid polymer can be used as the fluid. Furthermore, a mixture can be used as the fluid. For example, the mixture can be a mixture of water, ethylene glycol, and other functional components.

  The plurality of microparticles 1 are particles of nanometer size, micrometer size, etc., and are dispersed in a form surrounded by solvent molecules in the heat transport fluid. The fine particle 1 is a particle having a rod-like or spherical outer shape. The fine particles 1 are made of, for example, a metal such as gold (Au), silver (Ag), copper (Cu), iron (Fe), nickel (Ni), or an inorganic substance such as silicon (Si) or fluorine (F). Particles, particles made of oxides such as alumina (Al2O3), magnesium oxide (MgO), copper oxide (CuO), ferric trioxide (Fe2O3), titanium oxide (TiO), polymer particles made of carbon nanotubes or resins Can be used. Moreover, the microparticle 1 may be comprised from two or more types of substances.

  The substance that changes in a solid-liquid phase in a specific temperature range of the present embodiment is a substance that has a property of changing phase between a solid phase and a liquid phase at a temperature unique to the substance, and has a large latent heat. Examples of this substance include paraffins, barium hydroxide octahydrate, sodium acetate trihydrate, calcium chloride hexahydrate, sodium thiosulfate pentahydrate, sodium sulfate decahydrate, magnesium chloride hexahydrate. Examples thereof include inorganic hydrates such as hydrate and magnesium nitrate hexahydrate, and polyhydric alcohols such as pentaerythritol, mannitol, erythritol, threitol, xylitol, and sorbitol. By employing such a substance having a large latent heat, a heat transport fluid having a larger heat transport amount can be formed.

  In this heat transport fluid, heat transport is performed by utilizing the endothermic and exothermic heat of the latent heat accompanying the change in the solid-liquid phase of the substance that changes in the solid-liquid phase in a specific temperature range. FIG. 1 is a diagram for explaining a phase change of a substance 2 that changes in a solid-liquid phase when encapsulated in microparticles 1, (a) shows a state at a high temperature, and (b) shows a state at a low temperature. Represents a state. 2A and 2B are diagrams for explaining the phase change of the substance 2 that undergoes a solid-liquid phase change in a state where the microparticles 1 are coated. FIG. 2A shows a state at a high temperature, and FIG. 2B shows a state at a low temperature. Represents. In FIG. 1 and FIG. 2, for easy understanding, a solid-liquid phase changing substance 2 that is integrated with one minute particle 1 is shown in a solid-liquid phase change. A large number of such single fine particles are dispersed in the solvent and are present in contact with or away from each other. That is, the microparticles 1 exist as a single floating in the solvent, or a plurality of microparticles 1 are connected or agglomerated.

  The microparticles 1 can be formed in various shapes such as a rod shape, a spherical shape, and a polyhedral shape, but the microparticles 1 shown in FIGS. 1 and 2 are formed of rod-shaped particles. The aspect ratio (the ratio of the long side to the short side of the rod-like particle. Here, the long side (vertical length): the short side (horizontal width)) is, for example, 5 It is in the range of ~ 1000.

  A microparticle 1 shown in FIG. 1 contains a substance 2 that undergoes a solid-liquid phase change and exists in a solvent. Furthermore, such fine particles 1 are dispersed in a stable state in a solvent. The solid-liquid phase-changing substance 2 is a liquid in a high temperature range (predetermined temperature or a temperature range higher than the predetermined temperature range) in the operating temperature range (for example, −30 to 260 ° C.) of the heat transport fluid. It exists in a state and has a property of existing in a solid state in a low temperature range (a predetermined temperature or a temperature range lower than the predetermined temperature range).

  That is, in the high temperature range, as shown in FIG. 1A, the substance 2 changes from a solid to a liquid and is in an endothermic reaction (the portion indicated by hatching in the figure). And if it becomes a low temperature range, as shown in the state of (b) shown in Drawing 1, substance 2 will change from a liquid to a solid, and will be in a state accompanied by exothermic reaction (part enclosed with a dashed line of a figure).

  As described above, the heat-transporting fluid changes the solid-liquid phase change substance 2 from a liquid to a solid in a specific temperature range lower than a predetermined temperature specific to the substance and releases heat to the outside. In a specific temperature range exceeding this temperature, it changes from solid to liquid and absorbs heat from the outside. Thereby, this heat transport fluid changes between the state which generate | occur | produces by a solid-liquid phase change, and the state which absorbs heat in the temperature range to be used.

  Here, the two states shown in FIG. 1 change reversibly with the absorption of heat from the outside or the release of heat to the outside. And it has confirmed that the amount of latent heat accompanying the solid phase change between the high temperature state and the low temperature state according to the present embodiment is also large, and a large amount of heat can be transported through the change of these states. .

  For example, according to the calculation result of the simulation, when 2 Vol% of carbon nanotubes having an aspect ratio of 50 as fine particles 1 are dissolved in water, the thermal conductivity is from 0.60 W / (m · K) in the case of water alone. 1.14 W / (m · K) is improved, but when erythritol (filling rate of carbon nanotube is 50%) is included as substance 2 in the carbon nanotube, the improvement effect is further increased, and heat conduction The rate is calculated to be 1.64 W / (m · K).

  The microparticles 1 enclosing the substance 2 that changes the solid-liquid phase are, for example, suspension polymerization method, miniemulsion polymerization method, emulsion polymerization method, soap-free polymerization method, dispersion polymerization method, interfacial polycondensation reaction method, liquid Manufactured using chemical methods such as medium curing methods, submerged drying methods, phase inversion emulsification methods, coacervation methods, heteroaggregation methods, and other physicochemical methods, spray drying methods, hybridization methods, and other mechanical methods. can do. Further, in the case of rod-like particles such as carbon nanotubes, supercritical carbon dioxide can be produced by infiltrating the carbon nanotubes together with the substance 2 that changes the solid-liquid phase.

  Further, as shown in FIG. 2, the microparticles 1 may be present in the solvent in a state of being covered with the substance 2 that undergoes a solid-liquid phase change. Further, the microparticles 1 coated with the substance 2 in this manner are also dispersed in a stable state in the solvent. When the substance 2 that coats the surface of the microparticle 1 reaches a high temperature range, as shown in FIG. 2 (a), the substance 2 wraps around the microparticle 1 and changes its heat from solid to liquid. It becomes a state accompanied by a reaction (the part shown by the oblique line in the figure). When the temperature is low, the substance 2 is changed from a liquid to a solid in a state where the fine particles 1 are wrapped, as shown in FIG. Part surrounded by). Also in this case, the heat transport fluid changes between a state in which heat is generated by a solid-liquid phase change and a state in which heat is absorbed in the temperature range to be used. Even in the two states shown in FIG. 2, it changes reversibly with the absorption of heat from the outside or the release of heat to the outside.

  The heat transport fluid including the microparticles 1 coated with the solid-liquid phase-changing substance 2 is obtained by, for example, adding the substance 2 to a solution containing the microparticles 1 in a solvent and performing ultrasonic irradiation or the like. 2 covers the periphery of the microparticle 1 and can be produced. Furthermore, the heat transport medium is manufactured by covering the microparticles 1 with a coating agent by ultrasonic irradiation, adding the substance 2 that changes in solid-liquid phase, and again irradiating with ultrasonic waves to coat the surroundings. You can also. In addition, the heat transport medium adds a substance 2 as a coating agent to a solution containing the fine particles 1 in a solvent and performs ultrasonic irradiation or the like, so that the substance 2 forms a protective film around the fine particles 1. It can be formed and manufactured.

  Next, the example which applied the heat transport fluid of this embodiment to the heat transport apparatus 10 is demonstrated according to FIG. FIG. 3 is a schematic diagram showing the configuration of the heat transport device 10. The heat transport device 10 is a device that moves the heat of the first member 11 to the second member 14. In this embodiment, the heat transport device 10 passes through the first member 11, the second member 14 having a temperature lower than that of the first member 11, and the first member 11 and the second member 14. And a circulating means for circulating the heat transport fluid. For example, the heat of the first member 11 is the heat of the vehicle engine, and the second member 14 is a radiator.

  The heat transport fluid is circulated so that heat is transferred between the first member 11 and the second member 14 having a temperature lower than that of the first member 11. Specifically, the heat transport fluid is forcibly circulated by a pump 13 serving as a circulation means in a circulation circuit connecting the high temperature side passage 12 and the low temperature side passage 15. For example, in this apparatus, the heat transport fluid absorbs heat from the first member 11 that becomes hot due to the heat of the engine when passing through the high temperature side passage 12, and touches the outside air when passing through the low temperature side passage 15 to reduce the temperature. Heat is released to the radiator (second member 14).

  Here, the temperature of the first member 11 is higher than the temperature at which the substance that undergoes the solid-liquid phase change of the heat transport fluid changes, and the temperature of the second member 14 is the phase change of the substance that undergoes the solid-liquid phase change. The temperature is lower than the For this reason, when the heat transport fluid passes through the high temperature side passage 12, it absorbs the latent heat accompanying the phase change from solid to liquid as well as heat absorption by normal heat conduction. Next, when passing through the low temperature side passage 15, the heat release by the normal heat conduction and the latent heat accompanying the phase change from the liquid to the solid are released. That is, the heat transport fluid has a heat transport effect of absorbing the amount of heat obtained by the phase change from the first member 11 and releasing it to the second member 14 and dramatically increases the heat transport amount.

  As described above, according to the heat transport fluid according to this embodiment, the effects listed below can be obtained. The heat transport fluid of this embodiment includes a solvent containing water or an organic substance, microparticles 1 dispersed in the solvent, and a substance that undergoes a solid-liquid phase change in a specific temperature range. According to such a configuration, heat transport is promoted by utilizing the heat absorption and heat generation of the latent heat accompanying the solid-liquid phase change, and a heat transport fluid having a high heat transfer coefficient can be obtained. Latent heat is the total amount of heat energy required when the phase of a substance changes, and heat is generated when the substance undergoes a phase transition from a solid to a liquid, and heat is generated when the opposite liquid undergoes a phase transition. If this heat transport fluid is used, heat transport can be promoted by utilizing the latent heat accompanying such a solid-liquid phase change.

  Moreover, when the microparticle 1 is a rod-shaped particle, heat transfer in the longitudinal direction of the microparticle 1 can be improved.

  Moreover, the microparticle 1 includes at least one kind of substance 2 that undergoes a solid-liquid phase change in a specific temperature range. According to this structure, since the substance 2 exists in the inside of the microparticle 1, the substance 2 can be contained in the solvent in a stable state. In addition, since the substance 2 is encased in the microparticles 1, a surfactant or the like for dispersing in the solvent may be attached to the microparticles 1, and the effect that it is not necessary to attach to the substance 2 is obtained.

  The fine particles 1 are coated with at least one substance 2 that undergoes a solid-liquid phase change in a specific temperature range. According to this structure, since the substance 2 exists in the state surrounding the microparticles 1, the substance 2 can be contained in the solvent in a state stabilized in the solvent. Further, since the substance 2 covers the microparticles 1, a surfactant or the like for dispersing in the solvent may be attached to the substance 2, and the effect that it is not necessary to attach to the microparticles 1 is obtained.

  The substance 2 that undergoes a solid-liquid phase change is preferably paraffins. When this substance is employed, since the melting point of paraffins is about 40 to 75 ° C., heat transport can be promoted by latent heat at the use temperature including this temperature range.

  Moreover, it is preferable that the solid-liquid phase-changing substance 2 is barium hydroxide octahydrate which is an inorganic hydrated salt. When this substance is employed, since the melting point of barium hydroxide octahydrate is 78 ° C., heat transport can be promoted by latent heat at the use temperature including this temperature.

  Moreover, it is preferable that the solid-liquid phase-changing substance 2 is sodium acetate trihydrate which is an inorganic hydrate salt. When this substance is employed, since sodium acetate trihydrate has a melting point of 58 ° C., heat transport can be promoted by latent heat at the use temperature including this temperature.

  Moreover, it is preferable that the solid-liquid phase-changing substance 2 is calcium chloride hexahydrate which is an inorganic hydrate salt. When this substance is employed, since calcium chloride hexahydrate has a melting point of 30 ° C., heat transport can be promoted by latent heat at the use temperature including this temperature.

  Moreover, it is preferable that the solid-liquid phase-changing substance 2 is sodium thiosulfate pentahydrate which is an inorganic hydrate salt. When this substance is employed, since the melting point of sodium thiosulfate pentahydrate is 48 ° C., heat transport can be promoted by latent heat at the use temperature including this temperature.

  Moreover, it is preferable that the solid-liquid phase-changing substance 2 is sodium sulfate decahydrate which is an inorganic hydrate salt. When this substance is employed, since sodium sulfate decahydrate has a melting point of 32 ° C., heat transport can be promoted by latent heat at the use temperature including this temperature.

  Moreover, it is preferable that the solid-liquid phase-changing substance 2 is magnesium chloride hexahydrate which is an inorganic hydrate salt. When this substance is employed, the melting point of magnesium chloride hexahydrate is 117 ° C., so that heat transport can be promoted by latent heat at the use temperature including this temperature.

  Further, the substance 2 that undergoes a solid-liquid phase change is preferably magnesium nitrate hexahydrate which is an inorganic hydrated salt. When this material is employed, the melting point of magnesium nitrate hexahydrate is 89 ° C., and therefore, heat transport can be promoted by latent heat at the use temperature including this temperature.

  Moreover, it is preferable that the solid-liquid phase-changing substance 2 is pentaerythritol which is a polyhydric alcohol. When this substance is employed, since the melting point of pentaerythritol is 260 ° C., heat transport can be promoted by latent heat at the use temperature including this temperature.

  Moreover, it is preferable that the substance 2 which changes a solid-liquid phase is mannitol which is a polyhydric alcohol. When this substance is employed, since the melting point of mannitol is 166 to 168 ° C., heat transport can be promoted by latent heat at the use temperature including this temperature range.

  The solid-liquid phase-changing substance 2 is preferably a polyhydric alcohol erythritol. When this substance is employed, since the melting point of erythritol is 119 ° C., heat transport can be promoted by latent heat at the use temperature including this temperature.

  The solid-liquid phase-changing substance 2 is preferably a polyhydric alcohol, threitol. When this substance is employed, since the melting point of threitol is 87 ° C., heat transport can be promoted by latent heat at the use temperature including this temperature.

  The solid-liquid phase-changing substance 2 is preferably a polyhydric alcohol xylitol. When this substance is employed, since the melting point of xylitol is 93 to 95 ° C., heat transport can be promoted by latent heat at the use temperature including this temperature range.

  The solid-liquid phase-changing substance 2 is preferably a polyhydric alcohol sorbitol. When this substance is employed, since the melting point of sorbitol is 110 to 112 ° C., heat transport can be promoted by latent heat at the use temperature including this temperature range.

  Moreover, it is preferable that the average length (long side length) in the longitudinal direction of the rod-shaped microparticle 1 is in the range of 1 nm to 10 μm. According to this, the surface area of the fine particles 1 dispersed in the solvent is dramatically increased, so that heat can be absorbed and generated more efficiently. For this reason, the further improvement of the heat transport capability as a heat transport fluid can be anticipated.

  The average diameter of the spherical microparticles 1 is preferably in the range of 1 nm to 10 μm. According to this, the surface area as the fine particles dispersed in the solvent is remarkably increased, so that heat can be absorbed and generated more efficiently. For this reason, the further improvement of the heat transport capability as a heat transport fluid can be anticipated.

  Further, when ethylene glycol is used as a solvent, it has a freezing point depressing action, and the freezing point of the solvent can be lowered to about −20 ° C. That is, it becomes more excellent in practicality in cold districts such as in-vehicle cooling water and oil.

(Other embodiments)
The preferred embodiments of the present invention have been described above, but the present invention is not limited to the above-described embodiments, and various modifications can be made without departing from the spirit of the present invention.

  In the above embodiment, the form in which the solid-liquid phase-changing substance 2 is encapsulated or coated on the microparticle 1 as shown in FIG. 1 or FIG. 2 is not limited to such a form. The substance 2 may be present in the solvent in a state where it is attached to a part or almost the whole of the microparticles 1.

  In the above embodiment, as shown in FIG. 1 and FIG. 2, the form in which the substance 2 is encapsulated or covered with the rod-like microparticle 1 has been described. However, the present invention is limited to this form. Instead, for example, the microparticles 1 in which the substance 2 is encapsulated or covered may be spherical or other shapes.

  In addition to the solvents exemplified in the above embodiments, the following organic solvents can be used as the solvent contained in the heat transport fluid. Examples of the organic solvent include toluene, hexane, diethyl ether, chloroform, ethyl acetate, tetrahydrofuran, methylene chloride, acetone, acetonitrile, N, N-dimethylformamide, dimethyl sulfoxide, butanol acetate, 2propanol, 1-propanol, ethanol, methanol, Formic acid and the like.

  Moreover, you may use what consists of two types of components as a solvent contained in a heat transport fluid. Of these, one kind of solvent may be a liquid having a freezing point depressing action. For example, water can be used as the solvent, and potassium acetate, sodium acetate, or the like can be used as the freezing point depressant. According to such a structure, the practicality in a cold region etc. can further be improved by lowering the freezing point of the heat transport fluid. Furthermore, if necessary, in addition to the freezing point depressant, a rust inhibitor or an antioxidant may be added to the heat transport fluid as an additive. If there is no need to lower the freezing point of the heat transport fluid, two or more kinds of solvents that do not contain a freezing point depressant may be used.

It is a figure for demonstrating the phase change of the substance 2 which changes into a solid-liquid phase in the state enclosed by the microparticle 1, (a) represents the state at the time of high temperature, (b) represents the state at the time of a low temperature. Yes. It is a figure for demonstrating the phase change of the substance 2 which changes a solid-liquid phase in the state which coat | covered the microparticle 1, (a) represents the state at the time of high temperature, (b) represents the state at the time of low temperature. . It is a schematic diagram which shows the structure of the heat transport apparatus in which a heat transport fluid is used.

Explanation of symbols

1 ... fine particles 2 ... substance (substance that changes solid-liquid phase in a specific temperature range)
DESCRIPTION OF SYMBOLS 10 ... Heat transport apparatus 11 ... 1st member 13 ... Pump (circulation means)
14 ... Second member

Claims (6)

A solvent consisting of water ;
Microparticles dispersed in the solvent;
A substance that undergoes a solid-liquid phase change between a solid phase state and a liquid phase state in a specific temperature range; and
Including
The fine particles include gold (Au), silver (Ag), copper (Cu), iron (Fe), nickel (Ni), silicon (Si), alumina (Al ₂ O ₃ ), magnesium oxide (MgO), oxidation Particles made of any of copper (CuO), ferric trioxide (Fe ₂ O ₃ ), titanium oxide (TiO), and carbon nanotubes,
The microparticles are composed of rod-shaped particles having an average length in the longitudinal direction of 1 nm to 10 μm, and include at least one kind of the solid-liquid phase-changing substance ,
The solid-liquid phase-changing substance includes paraffins having a melting point of 40 to 70 ° C., barium hydroxide octahydrate, sodium acetate trihydrate, calcium chloride hexahydrate, sodium thiosulfate pentahydrate, A heat transport fluid characterized by being one of sodium sulfate decahydrate, magnesium nitrate hexahydrate, threitol, and xylitol . A solvent consisting of ethylene glycol or a mixture of water and ethylene glycol;
Microparticles dispersed in the solvent;
A substance that undergoes a solid-liquid phase change between a solid phase state and a liquid phase state in a specific temperature range; and
Including
The fine particles are gold (Au), silver (Ag), copper (Cu), iron (Fe), nickel (Ni), silicon (Si), alumina (Al ₂ O ₃ ), Magnesium oxide (MgO), copper oxide (CuO), ferric trioxide (Fe) ₂ O ₃ ), Titanium oxide (TiO), or carbon nanotube particles,
The microparticles are composed of rod-shaped particles having an average length in the longitudinal direction of 1 nm to 10 μm, and include at least one kind of the solid-liquid phase-changing substance,
The solid-liquid phase-changing substance includes paraffins having a melting point of 40 to 70 ° C., barium hydroxide octahydrate, sodium acetate trihydrate, calcium chloride hexahydrate, sodium thiosulfate pentahydrate, A heat transport fluid characterized by being one of sodium sulfate decahydrate, magnesium nitrate hexahydrate, threitol, and xylitol. A solvent consisting of ethylene glycol or a mixture of water and ethylene glycol;
Microparticles dispersed in the solvent;
A substance that undergoes a solid-liquid phase change between a solid phase state and a liquid phase state in a specific temperature range; and
Including
The fine particles are gold (Au), silver (Ag), copper (Cu), iron (Fe), nickel (Ni), silicon (Si), alumina (Al ₂ O ₃ ), Magnesium oxide (MgO), copper oxide (CuO), ferric trioxide (Fe) ₂ O ₃ ), Titanium oxide (TiO), or carbon nanotube particles,
The microparticles are composed of rod-shaped particles having an average length in the longitudinal direction of 1 nm to 10 μm, and include at least one kind of the solid-liquid phase-changing substance,
The heat transport fluid, wherein the solid-liquid phase-changing substance is any one of magnesium chloride hexahydrate, mannitol, erythritol, and sorbitol. The fine particles are carbon nanotubes;
The heat transport fluid according to claim 3 , wherein the solid-liquid phase-changing substance is erythritol . A first member;
A second member that is cooler than the first member;
Circulating means for circulating the heat transport fluid according to any one of claims 1 to 4 so as to pass through the first member and the second member;
A heat transport device comprising: The heat transport fluid according to any one of claims 1 to 4 is circulated so as to pass through the first member and the second member having a temperature lower than that of the first member, and the second member is circulated. A heat transport method comprising transporting heat from the member to the first member.

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