Automobile static temperature control system of coupled radiation refrigeration automobile cover and phase change heat storage module

Abstract

The invention discloses an automobile static temperature control system of a coupled radiation refrigeration automobile cover and a phase change heat storage module, and belongs to the field of heat management materials. A radiation refrigeration automobile cover covers an automobile, a phase change heat storage module is placed in the automobile, when temperature rises in the daytime, most heat is isolated by the radiation refrigeration automobile cover by reflecting solar radiation, high-density infrared radiation and low thermal conductivity, and when remaining heat enters a compartment, the interior of the compartment is kept in a low-temperature state through constant-temperature absorption of the phase change heat storage module; when the air temperature drops and at night, heat stored by the phase change heat storage module is quickly transmitted to the outside through high-density infrared radiation of the radiation refrigeration car cover, so that the interior of the compartment is in a low-temperature state. Under the dual-function coupling effect, the low-temperature state in a compartment is achieved, automobile starting temperature control energy consumption is reduced, the comfort degree of a human body is improved, and the risks of aging of elements in an automobile and spontaneous combustion of a power battery caused by high temperature are reduced.

Description

Technical Field

[0001] The present invention relates to the field of thermal management materials for passenger vehicles, and in particular to a high-efficiency temperature control system for passenger vehicles in static conditions, which utilizes a radiation cooling vehicle cover coupled with a phase change heat storage module. Background Art

[0002] Passenger cars are placed outdoors and exposed to the sun, especially in hot summer days. They absorb a large amount of solar radiation and ambient infrared radiation. A large amount of heat in the air also enters the car through convection and conduction, causing the temperature of the interior space and components to rise sharply. Long-term high temperature and ultraviolet light intake into the car will cause serious hazards such as aging of the interior, deterioration of tires and rubber parts, production of toxic gases, and damage to electronic equipment. Especially in new energy passenger cars, high temperature can easily cause circuit aging and chip damage, increasing the risk of spontaneous combustion of power batteries. On the other hand, the high temperature environment in the car increases the cooling energy consumption when the car is started, causing lower comfort for the human body. Therefore, efficient temperature control technology for passenger cars in static state is a technology that urgently needs to be developed and applied. When a passenger car is stationary, thermal management equipment such as air conditioning is usually turned off, and passive thermal management materials are needed to solve this problem.

[0003] Radiative cooling technology isolates external heat by reflecting sunlight, high infrared radiation, and low thermal conductivity to achieve efficient temperature control. By using a radiative cooling car cover to cover the outside of the passenger car, it is possible to isolate the external heat to a certain extent when the temperature rises during the day (by reflecting solar radiation, high-density infrared radiation, and low thermal conductivity), and to dissipate heat to the interior through high-density thermal radiation when the temperature drops and at night, thereby achieving cooling and cooling in the parking mode of the passenger car. However, when the temperature rises rapidly during the day, radiative cooling technology cannot completely isolate the external heat and will still absorb a certain degree of solar radiation. A small amount of heat in the closed compartment can cause the temperature inside the car to rise, and the cooling effect is not ideal.

[0004] Phase change heat storage can achieve temperature control by absorbing a large amount of heat at a constant temperature in the form of latent heat through physical phase change. The phase change heat storage module is placed in the car. When the temperature rises during the day, the heat absorbed in the car cabin (mainly solar radiation) can be stored in the phase change heat storage module at a constant temperature, thereby achieving a constant temperature control effect on the interior of the car. However, when the temperature rises during the day, the car cabin will absorb a large amount of solar radiation, and a large number of phase change heat storage modules need to be loaded to store this part of the heat in order to achieve continuous constant temperature control. On the other hand, when the temperature drops or at night, the heat dissipation efficiency of the closed car environment is very low, and the heat stored in the phase change heat storage module is difficult to quickly transmit to the outside world, which causes the car cabin to remain at a high temperature.

[0005] The radiant cooling car cover is composed of a commercial car cover base and a radiant cooling coating on the surface. It has the basic functions of radiant cooling, such as high solar reflectivity, high infrared emissivity and low thermal conductivity, and also needs to have good weather resistance and flexibility. CN219136684U discloses a car cover film with radiant cooling function, which achieves cooling and refrigeration by attaching to the surface of the car paint. However, the car cover film cannot cover the entire surface of the car, and solar radiation can still enter the car through the windshield. The cooling effect is limited in the static mode of the car, and it is different from the technical form of the present invention. On the other hand, for radiant cooling coatings, a large number of published patent documents are for applications in the outer layer of buildings or fixed objects, such as CN116640486A, CN115449252A, etc. When it is used for the surface of buildings or other fixed objects, it is necessary to consider the basic function and weather resistance of radiant cooling, but not the flexibility of the coating.

[0006] There are currently no public reports on the functional coupling of radiant cooling car covers and phase change heat storage modules for cooling and temperature control in static mode of the vehicle. Summary of the invention

[0007] In order to meet the needs of efficient refrigeration and cooling when the car is statically placed in the sun, the present invention aims to provide a material system for outdoor car cooling and heat dissipation, which is composed of an external radiation cooling car cover and a built-in phase change heat storage module. When the temperature rises during the day, the radiation cooling car cover isolates most of the heat by reflecting solar radiation, high-density infrared radiation and low thermal conductivity. When the remaining heat enters the car compartment, it can be absorbed at a constant temperature by the phase change heat storage module, so that the car compartment is kept at a low temperature. At this time, the phase change heat storage module can improve the cooling effect of the radiation cooling car cover, and the radiation cooling car cover can reduce the use of phase change materials; when the temperature drops and at night, a small amount of heat stored by the phase change heat storage module can be quickly transmitted to the outside world through the high-density infrared radiation of the radiation cooling car cover, so that the interior of the car is in a low temperature state. Under the dual-function coupling effect, the low temperature state inside the car compartment is achieved, the energy consumption of the car starting temperature control is reduced, the human comfort is improved, and the aging of the components in the car and the risk of spontaneous combustion of the power battery caused by high temperature are reduced.

[0008] The radiant cooling car cover of the present invention can be based on an ordinary commercial car cover, and a layer of radiant cooling coating is sprayed or painted on the surface. The radiant cooling coating is composed of a binder, a plasticizer, and an inorganic component, and meets the requirements of high solar reflectivity, high infrared emissivity, low thermal conductivity, weather resistance, and high flexibility.

[0009] Preferably, the preparation of the radiation cooling car cover is based on the commercial aluminum film car cover, and a layer of radiation cooling paint is applied on the outer layer. In addition to the radiation cooling properties, the paint also has weather resistance and flexibility. The radiation cooling coating of the present invention is to mix the binder, plasticizer, and inorganic components in water to form a coating, and then apply the coating to the surface of the car cover by spraying or painting, and dry naturally. Among them, the binder can be selected from water-based acrylic resin to provide high adhesion and high infrared emissivity. The plasticizer can be selected from one or more of polypropylene glycol, polyvinyl acetate, and carboxymethyl cellulose to enhance the flexibility of the coating. The inorganic component is a micron-sized particle or hollow microsphere with a high refractive index, preferably with a particle size of less than 3 μm, and its chemical composition is an inorganic oxide, which can be one or more of zinc oxide, aluminum oxide, silicon dioxide, titanium dioxide, magnesium oxide, etc., providing high solar spectrum reflectivity and infrared emissivity, improving weather resistance, and reducing thermal conductivity.

[0010] Preferably, the binder, plasticizer, and inorganic component are proportioned in a mass ratio of (40-60):(5-10):(30-55). First, weigh a specific mass of the inorganic component, mix it with water, and stir it for more than 2 hours to evenly disperse the inorganic particles to form a dispersion, in which the mass proportion of water is 30%-50%; then, weigh a specific proportion of the binder and plasticizer and mix them into the aforementioned dispersion, stir for 12-24 hours, so that the binder and plasticizer are fully dissolved to obtain a uniform coating. The coating is applied to the surface of the car cover by spraying or painting, and naturally air-dried. Through reasonable proportioning, the car cover achieves a solar spectrum reflectance of more than 80% and an infrared emissivity of more than 90%. Among them, the inorganic component can enhance the weather resistance, and the plasticizer component enhances the flexibility of the coating, which can be folded and stored in the car cover without falling off.

[0011] The phase change heat storage module is composed of phase change material, porous heat conductive skeleton, polymer, flame retardant, which can be used for in-vehicle temperature control and should have the characteristics of good shaping, suitable phase change temperature, high heat transfer efficiency, shape plasticity, flame retardancy, etc. Among them, the phase change material can be one or more of hexadecane, octadecane, eicosane, polyethylene glycol 800, and dodecanol, and its phase change temperature is 15°C-35°C, providing constant temperature heat storage characteristics, and the phase change temperature is near room temperature to achieve internal low temperature regulation. The porous heat conductive skeleton can be one of expanded graphite and graphene skeleton, providing encapsulation and high heat transfer efficiency. The polymer is polyethylene and / or polyethylene oxide, which can provide molecular bond force encapsulation, improve the shaping and shape plasticity of the phase change material. The flame retardant can be selected from one or more of aluminum hydroxide and magnesium hydroxide particles to provide flame retardancy.

[0012] Preferably, the phase change material, the porous thermal conductive skeleton, the polymer, and the flame retardant are mixed in a mass ratio of (50-60):(10-20):(10-30)(10-20), stirred evenly by a mechanical stirring method, heated to 80°C-150°C, adsorbed at a constant temperature for 2 hours, and pressed into sheets after cooling to obtain a phase change heat storage module with high thermal conductivity and good shaping properties in a specific shape, with a phase change temperature of 15°C-35°C and a heat storage density of 100 J / g-180 J / g. The phase change heat storage module is then embedded in the interior space of the vehicle.

[0013] The present invention uses the radiation cooling car cover and the phase change heat storage module for functional coupling. When the temperature rises during the day, the radiation cooling car cover isolates most of the heat by reflecting solar radiation, high-density infrared radiation and low thermal conductivity. When the remaining heat enters the car, it can be absorbed by the phase change heat storage module at a constant temperature, so that the car is kept in a low temperature state. At this time, the phase change heat storage module can improve the cooling effect of the radiation cooling car cover, and the radiation cooling car cover can reduce the use of phase change materials; when the temperature drops and at night, a small amount of heat stored by the phase change heat storage module can be quickly transmitted to the outside world through the high-density infrared radiation of the radiation cooling car cover, so that the interior of the car is in a low temperature state. Under the dual-functional coupling, the low temperature state inside the car is achieved, the energy consumption of the car starting temperature control is reduced, the human comfort is improved, and the aging of the components in the car and the risk of spontaneous combustion of the power battery caused by high temperature are reduced. The radiation cooling coating carried by the car cover has high solar reflectivity, high infrared emissivity, low thermal conductivity, weather resistance and flexibility, and the phase change heat storage module has good shaping, suitable phase change temperature, high heat transfer efficiency, plastic shape, flame retardancy, etc. The preparation method is safe and reliable and can be prepared on a large scale. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 Schematic diagram of the radiant cooling car cover prepared in Example 1 and its functions.

[0015] Figure 2 Example 1 Preparation of the solar reflectance spectrum (a) and solar reflectance (b) of the radiant cooling car cover before and after spraying the paint.

[0016] Figure 3 Example 1 Preparation of infrared emission spectrum (a) and infrared emissivity (b) of radiant cooling car cover before and after spraying the paint.

[0017] Figure 4 Appearance (upper figure) and microscopic morphology (lower figure) of the phase change heat storage module prepared in Example 1.

[0018] Figure 5 Experimental results of temperature control of a vehicle by coupling the radiant cooling car cover prepared in Example 1 with a phase change heat storage module. DETAILED DESCRIPTION

[0019] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the technical solution of the present invention is further described in detail below through embodiments in conjunction with the accompanying drawings.

[0020] Embodiment 1 The water-based acrylic resin, polypropylene glycol, hollow silica and water are mixed in a mass ratio of 30:5:15:50. Weigh a specific mass of hollow silica microspheres, mix them with a specific mass of water, and stir for more than 2 hours to evenly disperse the hollow silica to form a dispersion; weigh a specific mass of water-based acrylic resin and polypropylene glycol and mix them into the aforementioned dispersion, stir for 12-24 hours to fully dissolve the water-based acrylic resin and polypropylene glycol to obtain a uniform coating. Apply the coating to the surface of the aluminum film car cover by spraying or painting, and let it air dry naturally. The car cover achieves a solar spectrum reflectance of more than 80% ( Figure 2 ), infrared emissivity greater than 90% ( Figure 3 ), silica can enhance weather resistance, and polypropylene glycol enhances the flexibility of the coating, allowing it to be folded and stored in the car cover without falling off.

[0021] The mixture was prepared in a mass ratio of 60:20:10:10 for eicosane: expanded graphite: polyethylene: aluminum hydroxide. After being uniformly stirred by mechanical stirring, the mixture was heated to 120°C and adsorbed at a constant temperature for 2 hours. After being cooled, the mixture was pressed into a sheet to obtain a phase change heat storage module with high thermal conductivity and good shaping properties in a specific shape ( Figure 4 ), the phase change temperature is 30℃-32℃, the heat storage density is 140J / g, and then the phase change heat storage module is embedded in the interior space of the vehicle.

[0022] The exterior of the vehicle is covered with a radiation cooling car cover and a phase change heat storage module is placed inside the vehicle (such as the bottom of the seat, the gap in the compartment). Compared with a bare vehicle, a single radiation cooling car cover, and a commercial car cover, the dual-function main driving position has the lowest daytime temperature peak, fast heat dissipation at night, and the vehicle is continuously kept at a low temperature, achieving super cooling and heat dissipation functions ( Figure 5 ).

[0023] Embodiment 2 The water-based acrylic resin, carboxymethyl cellulose, aluminum oxide and water are mixed in a mass ratio of 25:5:20:50. Weigh a specific mass of aluminum oxide particles, mix them with a specific mass of water, and stir for more than 2 hours to evenly disperse the aluminum oxide particles to form a dispersion; weigh a specific mass of water-based acrylic resin and carboxymethyl cellulose and mix them into the aforementioned dispersion, stir for 12-24 hours, so that the water-based acrylic resin and polypropylene glycol are fully dissolved to obtain a uniform coating. Apply the coating to the surface of the aluminum film car cover by spraying or painting, and let it air dry naturally. The car cover achieves a solar spectrum reflectance of more than 80% and an infrared emissivity of more than 90%. Aluminum oxide can enhance weather resistance, and carboxymethyl cellulose enhances the flexibility of the coating, which can be folded and stored in the car cover without falling off.

[0024] The mixture is prepared in a mass ratio of 50:15:20:15 of polyethylene glycol 800:graphene:polyethylene oxide:aluminum hydroxide, and is evenly stirred by mechanical stirring, heated to 100°C, adsorbed at a constant temperature for 2 hours, and pressed into sheets after cooling to obtain a phase change heat storage module with high thermal conductivity and good shaping properties in a specific shape. The phase change temperature is 28°C-30°C, and the heat storage density is 110J / g. The phase change heat storage module is then embedded in the interior space of the vehicle.

[0025] By covering the outside of the car with a radiant cooling cover and placing phase change heat storage modules inside the car (such as under the seats and in the gaps in the car), super cooling and heat dissipation functions are achieved.

[0026] Embodiment 3 The water-based acrylic resin, polyvinyl acetate, titanium dioxide and water are mixed in a mass ratio of 20:5:25:50. Weigh a specific mass of titanium dioxide particles, mix them with a specific mass of water, and stir for more than 2 hours to evenly disperse the titanium dioxide particles to form a dispersion; weigh a specific mass of water-based acrylic resin and polyvinyl acetate and mix them into the aforementioned dispersion, stir for 12-24 hours, so that the water-based acrylic resin and polyvinyl acetate are fully dissolved to obtain a uniform coating. Apply the coating to the surface of the aluminum film car cover by spraying or painting, and air dry naturally. The car cover achieves a solar spectrum reflectance of more than 80% and an infrared emissivity of more than 90%. Titanium dioxide can enhance weather resistance, and polyvinyl acetate enhances the flexibility of the coating, which can be folded and stored in the car cover without falling off.

[0027] The mixture is prepared in a mass ratio of 55:10:20:15 of dodecanol: expanded graphite: polyethylene oxide: magnesium hydroxide. The mixture is uniformly stirred by mechanical stirring, heated to 80°C, adsorbed at a constant temperature for 2 hours, and pressed into sheets after cooling to obtain a phase change heat storage module with high thermal conductivity and good shaping properties in a specific shape. The phase change temperature is 20°C-25°C, and the heat storage density is 130 J / g. The phase change heat storage module is then embedded in the interior space of the vehicle.

[0028] By covering the outside of the car with a radiant cooling cover and placing a phase change heat storage module inside the car (such as under the seats and in the gaps in the car), the dual-function coupling achieves super cooling and heat dissipation functions.

[0029] The embodiments described above further illustrate the objectives, technical solutions and beneficial effects of the present invention in detail. It should be understood that the above are only some embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A static temperature control system for an automobile, comprising a radiation cooling car cover covering the automobile and a phase change heat storage module placed in the automobile, characterized in that: The surface layer of the radiation cooling car cover is a radiation cooling coating, whose solar spectrum reflectivity is greater than 80% and infrared emissivity is greater than 90%; the phase change temperature of the phase change heat storage module is 15°C-35°C, and the heat storage density is 100J / g-180 J / g.

2. The automotive static temperature control system according to claim 1, characterized in that: The radiation cooling car cover is prepared by spraying or painting a layer of radiation cooling coating on the surface of an ordinary car cover as a base, and the radiation cooling coating is composed of a binder, a plasticizer and an inorganic component, wherein the binder is a water-based acrylic resin; the plasticizer is selected from one or more of polypropylene glycol, polyvinyl acetate, and carboxymethyl cellulose; and the inorganic component is micron-sized inorganic oxide particles or hollow microspheres.

3. The automotive static temperature control system according to claim 2, characterized in that: The particle size of the inorganic oxide particles or hollow microspheres is less than 3 μm.

4. The automotive static temperature control system according to claim 2, characterized in that: The chemical composition of the inorganic component is selected from one or more of zinc oxide, aluminum oxide, silicon dioxide, titanium dioxide and magnesium oxide.

5. The automotive static temperature control system according to claim 2, characterized in that: The mass ratio of the binder, the plasticizer and the inorganic component in the radiation cooling coating is (40-60):(5-10):(30-55).

6. The automotive static temperature control system according to claim 2, characterized in that: The radiation cooling car cover is prepared by the following method: weighing an inorganic component, mixing it with water, wherein the mass proportion of water is 30%-50%, and stirring for more than 2 hours to form a uniform dispersion; weighing a binder and a plasticizer, mixing them into the dispersion, and stirring for 12-24 hours to fully dissolve the binder and the plasticizer to obtain a uniform coating; The coating is applied to the surface of an ordinary car cover by spraying or painting, and is naturally air-dried to obtain a radiation cooling car cover.

7. The automotive static temperature control system according to claim 1, characterized in that: The phase change heat storage module is composed of a phase change material, a porous heat conductive skeleton, a polymer and a flame retardant, wherein the phase change temperature of the phase change material is 15°C-35°C.

8. The automobile static temperature control system according to claim 7, characterized in that: The phase change material is selected from one or more of hexadecane, octadecane, eicosane, polyethylene glycol 800, and dodecanol; the porous thermal conductive skeleton is expanded graphite or graphene; the polymer is polyethylene and / or polyethylene oxide; and the flame retardant is aluminum hydroxide and / or magnesium hydroxide particles.

9. The automobile static temperature control system according to claim 7, characterized in that: The mass ratio of the phase change material, the porous thermal conductive skeleton, the polymer and the flame retardant in the phase change heat storage module is (50-60):(10-20):(10-30)(10-20).

10. The automobile static temperature control system according to claim 7, characterized in that: The phase change heat storage module is prepared by the following method: the phase change material, the porous heat conductive skeleton, the polymer and the flame retardant are mixed by mechanical stirring, then heated to 80°C-150°C, adsorbed at a constant temperature for 2 hours, and pressed into sheets after cooling to obtain the phase change heat storage module of a specific shape.

Images