Ventilation heat preservation and insulation roof and control method thereof

Abstract

The invention discloses a ventilation, heat preservation and heat insulation roof and a control method thereof. The ventilation, heat preservation and heat insulation roof comprises a roof structure, an air blowing mechanism and an opening and closing mechanism. The roof structure comprises a plurality of phase change layers which are sequentially arranged from inside to outside, the phase change temperatures of the phase change layers are sequentially increased, a structural layer and a ventilation layer are arranged between the phase change layer close to the indoor side and the adjacent phase change layer, the ventilation layer is arranged on the outer side of the structural layer, and a ventilation skylight is arranged at the top of the roof structure. The ventilation layer comprises a plurality of air ducts arranged side by side in the length direction of the roof, air inlets are formed in the sides, close to the ventilation skylight, of the air ducts, and air outlets are formed in the sides, away from the ventilation skylight, of the air ducts. The blowing mechanism is arranged on the roof, the input end communicates with the outside, and the output end communicates with the air inlet; and the opening and closing mechanism is arranged at the air outlet. According to the invention, the defect that single phase change temperature cannot play a role in heat preservation and heat insulation all year round can be overcome, and meanwhile, effective heat dissipation can be carried out at night in diurnal small temperature difference regions.

Description

Technical Field

[0001] This invention relates to the fields of phase change insulation, ventilation technology, and photovoltaic applications, specifically a ventilated and heat-insulating roof and its control method. Background Technology

[0002] Buildings are a major contributor to global energy consumption and carbon dioxide emissions. Studies have found that buildings account for 36% of total energy consumption and 39% of total carbon dioxide emissions. With continuous industrial development, my country's industrial buildings have also seen significant growth, with data showing that their proportion now exceeds that of residential buildings. Industrial production consumes 70% of total social energy consumption, with buildings themselves accounting for approximately 15% of that. Furthermore, industrial plants typically have larger floor areas and roofs far exceeding those of residential buildings, resulting in greater heat entering the plant through the roof and a higher indoor cooling load. Many workers now spend extended periods in industrial buildings, and the roofs of most Chinese industrial plants are constructed with corrugated steel sheets, offering poor insulation. Especially in summer, the surface temperature of the roof can sometimes reach 70°C, directly impacting worker comfort and causing a sharp increase in air conditioning energy consumption. Therefore, reducing heat entering industrial plants and lowering building energy consumption, developing roof structures with excellent thermal insulation properties, are crucial measures to improve the energy efficiency of lightweight industrial buildings.

[0003] Phase Change Material (PCM), as a novel energy-saving material, possesses low thermal conductivity and heat absorption / release properties. When its state changes, it undergoes heat release or absorption in a near-isothermal state, effectively addressing the mismatch between time and space. Unlike conventional insulation materials, PCM exhibits both thermal resistance and thermal fusion properties, effectively reducing heat transfer through the roof and lowering building energy consumption. Studies have shown that compared to ordinary roofs, the inner surface temperature of a PCM roof can be delayed by more than 3 hours, demonstrating a significant insulation effect. Integrating PCM into building envelopes can reduce indoor air temperature fluctuations and energy consumption, thereby achieving building energy conservation and emission reduction. Therefore, PCM is widely used in building envelopes.

[0004] In hot-summer and cold-winter or hot-summer and warm-winter regions of my country, summers are hot and humid with small diurnal temperature variations. Applying PCM to roof structures can reduce heat transfer. However, when PCM solidifies and releases heat at night, the small diurnal temperature range leads to incomplete heat release, affecting the amount of heat absorbed during melting in the next phase change cycle. Therefore, in regions with small diurnal temperature variations, heat dissipation is not effective at night. Furthermore, most existing research uses single-layer phase change materials for roof structures. The drawback is that the phase change temperature of a single-layer phase change material is fixed, and phase change only occurs when external conditions reach or exceed the phase change temperature of the PCM. Sometimes, the selected PCM has a phase change temperature that is too high or too low, making it suitable only for summer or winter use and unable to function year-round. Summary of the Invention

[0005] The purpose of this invention is to provide a ventilated, heat-insulating roof and its control method, which can solve the shortcomings of a single phase change temperature roof that cannot play a role in heat insulation and heat preservation throughout the year, and at the same time can effectively dissipate heat at night in areas with small temperature differences between day and night.

[0006] The technical solution of this invention is: a ventilated, heat-insulating roof, comprising a roof structure, a blower mechanism, and an opening and closing mechanism; the roof structure includes multiple phase change layers arranged sequentially from the inside to the outside, the phase change temperature of the multiple phase change layers increasing sequentially from the inside to the outside, a structural layer and a ventilation layer are provided between the phase change layer near the interior and its adjacent phase change layer, the ventilation layer is located on the outside of the structural layer, a ventilation skylight is provided at the top of the roof structure, the ventilation layer includes multiple air ducts arranged side by side along the length of the roof, an air inlet is provided on the side of the air duct near the ventilation skylight, and an air outlet is provided on the side of the air duct away from the ventilation skylight; the blower mechanism is located at the roof, the input end of the blower mechanism is connected to the outside, and the output end of the blower mechanism is connected to the air inlet, for introducing air into the ventilation layer for heat dissipation; the opening and closing mechanism is located at the air outlet, for opening or closing the air outlet.

[0007] Preferably, as a further improvement of the present invention, there are three phase change layers, namely a first phase change layer, a second phase change layer and a third phase change layer arranged sequentially from the inside to the outside. The structural layer is disposed outside the first phase change layer, and the ventilation layer is disposed between the structural layer and the second phase change layer. The phase change temperature range of the first phase change layer is 8℃~11℃, the phase change temperature range of the second phase change layer is 32℃~36℃, and the phase change temperature range of the third phase change layer is 37℃~41℃.

[0008] Preferably, as a further improvement of the present invention, the phase transition temperature of the first phase transition layer is 10°C, the phase transition temperature of the second phase transition layer is 35°C, and the phase transition temperature of the third phase transition layer is 39°C.

[0009] Preferably, as a further improvement of the present invention, the phase change material of the first phase change layer is 15# paraffin wax, the phase change material of the second phase change layer includes lauric acid and myristica fragrans, the mass ratio of lauric acid and myristica fragrans is 70:30, and the phase change material of the third phase change layer includes lauric acid and stearic acid, the mass ratio of lauric acid and stearic acid is 82:18.

[0010] Preferably, as a further improvement of the present invention, the blower mechanism includes a blower, a Y-shaped tee pipe, and an air supply pipe A. The air inlet of the blower is connected to a branch pipe B in the Y-shaped tee pipe, a branch pipe C in the Y-shaped tee pipe is connected to the ventilation skylight, a branch pipe D in the Y-shaped tee pipe is connected to the outside air, the air outlet of the blower is connected to the air supply pipe A, the side wall of the air supply pipe A is connected to each air duct, and each of the air supply pipe A, branch pipe C, and branch pipe D is provided with an electric air valve. Each electric air valve and the blower are electrically connected to the temperature control component.

[0011] Preferably, as a further improvement of the present invention, the opening and closing mechanism includes a baffle that can slide up and down at the air outlet. The baffle is controlled to slide up and down by a lifting component, and the lifting component is electrically connected to the temperature control component.

[0012] Preferably, as a further improvement of the present invention, it also includes a temperature control component, which is electrically connected to the electric air valve, the fan, and the lifting component, respectively, for controlling the opening and closing of the blower mechanism and the opening and closing mechanism according to different ambient temperatures. The temperature control component includes two temperature sensors, a controller, and a solar photovoltaic power generation system; the two temperature sensors are respectively located at the inlet ends of the branch pipe C and the branch pipe D; the controller is electrically connected to each of the temperature sensors, each electric air valve, the fan, and the lifting component; and the solar photovoltaic power generation system is electrically connected to the controller.

[0013] Preferably, as a further improvement of the present invention, the solar photovoltaic power generation system includes multiple solar panels and a solar battery. The multiple solar panels are laid on the ventilation skylight for converting solar energy into electrical energy. The solar battery is electrically connected to the multiple solar panels for receiving and storing the electrical energy transmitted by the solar panels. The controller is electrically connected to the solar battery.

[0014] Preferably, as a further improvement of the present invention, it further includes a reflective coating layer disposed outside the outermost phase change layer.

[0015] This invention also discloses a method for controlling ventilated, thermally insulated roofs, comprising the following steps:

[0016] Under summer operating conditions, the environment of the phase change ventilation and thermal insulation roof is determined to be either daytime or nighttime. If it is daytime, the roof will enter daytime operation mode; if it is nighttime, the roof will enter nighttime operation mode.

[0017] The daytime operation mode is as follows: the controller controls the air inlet, air outlet and each electric air valve to be closed, and the baffle in front of the air outlet slides down to block the air outlet, so that the ventilation layer is in a closed state. The solar panel converts solar energy into electrical energy and stores it in the solar battery. The controller controls the charging of the battery. Natural ventilation is carried out by the ventilation skylight. The exhaust air does not enter the ventilation layer and directly enters the atmosphere. When the outside temperature reaches the phase change temperature of the second phase change layer and the third phase change layer, the second phase change layer and the third phase change layer melt and absorb heat and store the heat in the form of latent heat to reduce indoor temperature fluctuations and peak temperatures.

[0018] The nighttime operation mode is as follows: the controller opens the air inlet, air outlet, and fan, and opens the baffle in front of the air outlet to form an open directional ventilation channel. The fan is driven by the electrical energy stored in the solar battery during the day. The temperature control component detects the air temperature inside the factory and the outdoor ambient air temperature. If the air temperature inside the factory is lower than the outdoor ambient air temperature, the electric air valves at branch pipe C and air supply pipe A are opened, and the electric air valve at branch pipe D is closed, thereby introducing the air exhausted from the factory into the ventilation layer for ventilation and heat dissipation. If the outdoor air temperature is lower than the air temperature inside the factory, the electric air valves at branch pipe D and air supply pipe A are opened, and the electric air valve at branch pipe C is closed, thereby introducing outdoor air into the ventilation layer for ventilation and heat dissipation, carrying away the heat released by the condensation of the second and third phase change layers, thus solving the problem of ineffective heat dissipation due to the small temperature difference between day and night in hot summer and cold winter regions, and indirectly improving its heat insulation effect during the day.

[0019] In winter, the controller keeps the air inlet, outlet, and all electric air valves closed, and slides down the baffle in front of the outlet to block it, ensuring the ventilation layer remains closed. Natural ventilation is achieved through the skylights, and the exhausted air directly enters the atmosphere. Due to the low winter temperatures, the third and second phase change layers do not undergo phase change, ensuring minimal heat dissipation from the roof with a low thermal conductivity. In winter, the outdoor ambient temperature is consistently lower than the indoor temperature of the factory. Therefore, when heat is transferred from the inside to the outside of the factory, the first phase change layer melts and absorbs heat to store some latent heat. When the temperature inside the factory is lower than the solidification phase change temperature of the first phase change layer, the first phase change layer solidifies and releases heat, dissipating the heat into the factory interior to raise the indoor temperature.

[0020] Compared with the prior art, the beneficial effects of the present invention are:

[0021] 1. This invention changes the previous design of single-layer phase change roofs by selecting multiple phase change layers with different phase change temperatures and placing them in different positions on the roof. This solves the problem that a single phase change temperature cannot play a role in heat preservation and insulation throughout the year, and improves the heat preservation and insulation effect of the phase change ventilated roof.

[0022] 2. In order to solve the problem that the phase change layer cannot effectively dissipate heat at night in areas with small temperature differences between day and night, this invention adds a ventilation layer to the roof structure. At night, the cooler air is introduced into the ventilation layer to carry away the heat emitted by the phase change layer during nighttime condensation, so that it can dissipate heat quickly and completely, ensuring the effectiveness of the phase change cycle.

[0023] 3. The present invention has three phase change layers. In summer, during the day, when the temperature of the outer surface of the roof is higher than the phase change temperature of the third and second phase change layers, the second and third phase change layers melt and absorb heat, storing the heat in the form of latent heat, thus playing a role in heat insulation. When the temperature of the outer surface of the roof drops to the solidification phase change temperature of the second and third phase change layers, the second and third phase change layers begin to solidify and release heat, releasing the latent heat stored during the day. In winter, when the outdoor ambient air temperature is lower than the temperature inside the factory building, heat is transferred from the inside to the outside. The first phase change layer on the inner side of the factory roof melts and absorbs heat to store some latent heat. When the temperature inside the factory building is lower than the solidification phase change temperature of the first phase change layer, the first phase change layer solidifies and releases heat, dissipating the heat into the interior of the factory building to play a role in heat preservation, thereby increasing the temperature inside the factory building.

[0024] 4. This invention effectively utilizes the factory's exhaust ventilation. In summer, during the day, natural ventilation is achieved through skylights, with the exhausted air entering the atmosphere directly without entering the ventilation layer. At night, the system switches between indoor and outdoor temperatures. If the indoor temperature is lower than the outdoor air temperature, the exhaust air is introduced into the ventilation layer; if the outdoor air temperature is lower than the indoor air temperature, outdoor air is used directly for ventilation and heat dissipation in the ventilation layer. In winter, the ventilation layer remains closed, so natural ventilation is achieved directly through skylights, with the exhausted air entering the atmosphere directly without entering the ventilation layer.

[0025] 5. In order to improve the heat dissipation effect of the ventilation layer, the present invention designs several air ducts of the same size in the roof ventilation layer. After the cooler air enters the air duct, it forms a directional airflow, thereby solving the problem of air "running around" after entering the cavity and forming turbulence or eddies, thus improving the auxiliary heat dissipation effect of the ventilation layer.

[0026] 6. This invention links phase change ventilation roof and solar photovoltaic power generation technology. The photovoltaic power generation system stores electrical energy during the day and uses batteries to drive the fan at night, effectively removing the heat released by the condensation of PCM. No additional energy is required, achieving zero power consumption operation of the mechanical device.

[0027] 7. The phase change ventilation and thermal insulation roof of the present invention effectively reduces the maximum heat flow entering the interior through the roof of the industrial plant, while delaying the time when the maximum heat flow occurs, reducing the amplitude of temperature fluctuation inside the plant, thereby reducing building energy consumption and improving the thermal comfort of workers inside the plant. Attached Figure Description

[0028] Figure 1 This is a three-dimensional structural diagram of the present invention;

[0029] Figure 2 This is a cross-sectional structural diagram of the present invention;

[0030] Figure 3 This is a schematic diagram of the heat transfer process of the present invention;

[0031] Figure 4 This is a schematic diagram showing the connection between the temperature control component and the blower mechanism in this invention;

[0032] Figure 5 This is a schematic diagram showing the connection between the blower mechanism and the ventilation layer in this invention;

[0033] Figure 6 This is a schematic diagram of the daytime operation mode of the present invention under summer conditions;

[0034] Figure 7 This is a schematic diagram of the nighttime operation mode of the present invention under summer working conditions;

[0035] Figure 8 This is a schematic diagram of the daytime operation mode of the present invention under winter conditions;

[0036] Figure 9 This is a schematic diagram of the nighttime operation mode of the present invention under winter conditions. Detailed Implementation

[0037] The following is in conjunction with the appendix Figure 1 To the attached Figure 9 The specific embodiments of the present invention will be described in detail below. In the description of the invention, it should be understood that the terms "center", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the present invention.

[0038] The terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature; in the description of the invention, unless otherwise stated, "a plurality of" means two or more.

[0039] Example 1

[0040] like Figures 1 to 9 As shown, this embodiment of the invention provides a ventilated, heat-insulating roof, including a roof structure, a blower mechanism, and an opening and closing mechanism. The roof structure includes multiple phase change layers arranged sequentially from the inside to the outside, with the phase change temperature of the multiple phase change layers increasing sequentially from the inside to the outside. A structural layer 2 and a ventilation layer 3 are provided between the phase change layer closer to the interior and its adjacent phase change layer. The ventilation layer 3 is located on the outside of the structural layer 2. A ventilation skylight 14 is provided at the top of the roof structure. The ventilation layer 3 includes multiple air ducts 15 arranged side by side along the length of the roof. An air inlet 7 is provided on the side of the air duct 15 closer to the ventilation skylight 14, and an air outlet 8 is provided on the side of the air duct 15 away from the ventilation skylight 14. The blower mechanism is located at the roof, with its input end connected to the outside and its output end connected to the air inlet 7, for introducing air into the ventilation layer 3 for heat dissipation. The opening and closing mechanism is located at the air outlet 8 for opening or closing the air outlet 8.

[0041] In this embodiment, by selecting multiple phase change layers with different phase change temperatures and placing them in different locations on the roof, the shortcomings of a single phase change temperature layer not being able to provide insulation and heat preservation throughout the year are solved, thus improving the insulation and heat preservation effect of the phase change ventilated roof. At the same time, in order to solve the problem of the phase change layer not being able to effectively dissipate heat at night in areas with small day-night temperature differences, a ventilation layer 3 is added to the roof structure. At night, air can be introduced into the ventilation layer 3 by a blower mechanism to dissipate heat, thereby removing the heat generated when the phase change layer solidifies and releases heat, allowing it to dissipate heat quickly and completely, ensuring the effectiveness of the phase change cycle, and thus solving the problem of the phase change layer not being able to effectively dissipate heat at night in areas with small day-night temperature differences.

[0042] To prevent poor heat dissipation due to the large area of ​​ventilation layer 3 causing air to "drift around" after entering, this invention divides the ventilation layer into several rectangular air ducts using aluminum alloy partitions. When cooler air enters the rectangular air ducts, it forms a directional airflow that carries away the heat dissipated by the condensation of the phase change layer. This ensures effective heat dissipation of the phase change layer while improving its heat insulation effect during the day. The ventilation layer 3 has a thickness of 40mm to 60mm and is made of aluminum alloy plate with a thickness of 10mm. The aluminum alloy plate serves both as a support and as a partition to divide the air gap into several ventilation channels.

[0043] Furthermore, in specific implementation, there are three phase change layers, namely, the first phase change layer 1, the second phase change layer 4, and the third phase change layer 5 arranged sequentially from the inside to the outside. The structural layer 2 is arranged outside the first phase change layer 1, and the ventilation layer 3 is arranged between the structural layer 2 and the second phase change layer 4. The phase change temperature range of the first phase change layer 1 is 8℃~11℃, the phase change temperature range of the second phase change layer 4 is 32℃~36℃, and the phase change temperature range of the third phase change layer 5 is 37℃~41℃.

[0044] Based on Example 1, this embodiment, in order to improve the heat insulation effect of a single phase change temperature during the phase change process, applies three different phase change layers to different locations in the roof structure. Specifically, lauric acid and stearic acid with a mass ratio of 82:18 at 39°C are selected as the third phase change layer 5, and a phase change material with a phase change temperature of 37-41°C can be used as a replacement material. Lauric acid and myristica fragrans with a mass ratio of 70:30 at 35°C are selected as the second phase change layer 4, and a phase change material with a phase change temperature of 32-36°C can be used as a substitute. The materials are changed. 15# paraffin wax at 10℃ is selected as the first phase change layer 1. Phase change materials with a phase change temperature of 8℃~11℃ can be used as replacement materials. The dimensions of all layers are 800mm×800mm×20mm. The second phase change layer 4 and the third phase change layer 5 are placed on the outer surface of the roof structure to play a role in heat insulation in summer. The combination of the second phase change layer 4 and the third phase change layer 5 can achieve a stepped phase change to improve the heat insulation effect in summer. The first phase change layer 1 is placed on the inner surface of the roof to play a role in heat preservation in winter.

[0045] In this embodiment, the phase change layer is encapsulated in an aluminum foil bag to prevent leakage during the melting process. The aluminum foil bag has advantages such as moisture resistance, airtightness, light shielding, and ensuring that the material does not deteriorate, and it also has a long service life. It is then further encapsulated with a heat-resistant and flame-retardant PVC board to form the phase change layer.

[0046] The specific method for preparing binary PCM is as follows (taking PCM at 39℃ as an example):

[0047] First, lauric acid (LA) and stearic acid (SA) are mixed at a mass ratio of 82:18, heated to 70°C to melt them into a liquid state, and stirred uniformly with a magnetic stirrer for 30 minutes to obtain a binary eutectic mixture. Second, the liquid binary phase change material is poured into an aluminum foil bag and sealed with a sealing machine, then placed on a platform to solidify into a solid state. Finally, the aluminum foil bag containing the solid phase change material is placed into a PVC board for secondary encapsulation to obtain a phase change layer.

[0048] In this embodiment, the factory roof is supported by a frame. The first phase change layer 1 is placed on a grid support of corresponding size on the inner surface of the roof. The length of the plate placed on the support is greater than 60mm. The first phase change layer is fixed to the frame by bolts. The third phase change layer 5 and the second phase change layer 4 are placed on the outer surface of the roof.

[0049] The blower mechanism includes a blower 10, a Y-shaped tee pipe, and an air supply pipe A. The air inlet of the blower 10 is connected to a branch pipe B in the Y-shaped tee pipe, a branch pipe C in the Y-shaped tee pipe is connected to a ventilation skylight 14, a branch pipe D in the Y-shaped tee pipe is connected to the outside air, and the air outlet of the blower 10 is connected to the air supply pipe A. The side wall of the air supply pipe A is connected to each air duct 15. Each air supply pipe A, branch pipe C, and branch pipe D is equipped with an electric air valve 9. Each electric air valve 9 and the blower 10 are electrically connected to the temperature control component.

[0050] In this embodiment, considering that industrial plants mostly use color steel plates, which have poor thermal insulation and are extremely hot and stuffy inside during summer, exhaust systems are generally installed on the roofs of industrial plants. Therefore, the air exhausted from the ventilation skylights 14 is utilized to improve the heat dissipation of the phase change layer. In summer, during the day, natural ventilation is carried out using the ventilation skylights 14, and the exhausted air does not enter the ventilation layer but directly enters the atmosphere. At night, the system switches according to the temperature difference between the inside and outside of the plant. If the air temperature inside the plant is lower than the outdoor air temperature, the exhaust air from the plant is introduced into the ventilation layer through branch pipe C. If the outdoor air temperature is lower than the air temperature inside the plant, outdoor air is directly introduced into the ventilation layer through branch pipe D for ventilation and heat dissipation. In winter, the ventilation layer is always closed, so natural ventilation is carried out directly using the ventilation skylights during winter, and the exhausted air does not enter the ventilation layer but directly enters the atmosphere.

[0051] The opening and closing mechanism includes a baffle 16 that can slide up and down at the air outlet 8. The baffle 16 is controlled to slide up and down by a lifting component, which can be an existing device such as an electric push rod. At night, when the temperature drops to a certain level, the baffle 16 is slid up by controlling the lifting component to open the air outlet 8. During the day, when the temperature rises, the baffle 16 is slid down by controlling the lifting component to close the air outlet 8.

[0052] Furthermore, in order to automatically control the opening process according to the temperature, a temperature control component is also included, which is electrically connected to the electric air valve 9, the fan 10, and the lifting component, respectively. It is used to control the opening and closing of the blower mechanism and the opening and closing mechanism according to different ambient temperatures. The temperature control component includes two temperature sensors, a controller 13, and a solar photovoltaic power generation system. The two temperature sensors are respectively set at the inlet ends of branch pipe C and branch pipe D. The controller 13 is electrically connected to each temperature sensor, each electric air valve 9, the fan 10, and the lifting component, respectively. The solar photovoltaic power generation system is electrically connected to the controller 13.

[0053] In this embodiment, the temperature sensor installed in branch pipe C can automatically detect the air temperature inside the factory at night, and the temperature sensor installed in branch pipe D can automatically detect the outdoor ambient air temperature at night. Based on the detected temperature, the controller 13 compares the two temperatures. If the air temperature inside the factory is lower than the outdoor ambient air temperature, the controller 13 opens the electric air valve 9 at branch pipe C and air supply pipe A, and closes the electric air valve 9 at branch pipe D, thereby introducing the air exhausted from the factory into the ventilation layer 3 for ventilation and heat dissipation. If the outdoor air temperature is lower than the air temperature inside the factory, the controller 13 opens the electric air valve 9 at branch pipe D and air supply pipe A, and closes the electric air valve 9 at branch pipe C, thereby introducing outdoor air into the ventilation layer 3 for ventilation and heat dissipation. At the same time, the controller 13 can also control the lifting component to drive the baffle 16 to rise and fall, thereby automatically realizing the opening and closing function of the air outlet 8.

[0054] Specifically, the solar photovoltaic power generation system includes multiple solar panels 12 and a solar battery 11. The multiple solar panels 12 are laid on the ventilation skylight 14 to convert solar energy into electrical energy. The solar battery 11 is electrically connected to the multiple solar panels 12 to receive and store the electrical energy transmitted by the solar panels 12. The controller 13 is electrically connected to the solar battery 11 and specifies and controls the charging and discharging conditions of the solar battery 11, and adjusts the power according to demand. When the battery voltage rises to a certain level, the charging of the battery is stopped. The solar battery 11 is electrically connected to the solar panels 12, the solar controller 13, and the wind turbine 10 to receive and store the electrical energy transmitted by the solar panels 12 and transmit the electrical energy to the wind turbine 10. The solar battery 11 can work uninterruptedly for 24 hours under the highest load, and the wind speed of the wind turbine 10 is adjustable.

[0055] In this embodiment, solar energy is converted into electrical energy by the solar panel 12 and stored in the solar battery 11 for use by the fan 10. In this embodiment, no additional energy is required, and the entire device is driven by renewable solar energy, realizing near-zero energy consumption operation of the mechanical device. At the same time, a small bracket can be built on the side of the factory roof to place the fan 10, solar battery 11 and solar controller 13 on the bracket.

[0056] Furthermore, the solar panel 12 is placed on the ventilation skylight 14 and covers the entire ventilation skylight 14. This arrangement ensures that the solar panel 12 generates enough electricity to power the fan 10.

[0057] Furthermore, in order to increase the solar radiation reflectivity of the roof and to a certain extent increase the thermal resistance of the roof, a reflective coating layer 6 composed of white acrylic emulsion is laid on the outermost layer of the industrial plant roof structure. The thickness of the reflective coating layer 6 is 1mm to 3mm.

[0058] Example 2

[0059] This invention discloses a method for controlling ventilated, thermally insulated roofs, comprising the following steps:

[0060] Under summer operating conditions, determine whether the environment of the phase change ventilation and thermal insulation roof is daytime or nighttime. If it is daytime, enter daytime operation mode; if it is nighttime, enter nighttime operation mode.

[0061] The daytime operation mode is as follows: The controller 13 keeps the air inlet 7, air outlet 8, and all electric air valves 9 closed, and slides down the baffle in front of the air outlet 8 to block it, thus sealing the ventilation layer 3. The solar panel 12 converts solar energy into electrical energy, which is stored in the solar battery 11. The controller 13 controls the charging of the battery. Natural ventilation is achieved through the ventilation skylight 14; the exhausted air does not enter the ventilation layer 3 but directly enters the atmosphere. When the outside temperature reaches the phase change temperature of the second phase change layer 4 and the third phase change layer 5, the second and third phase change layers 4 and 5 melt and absorb heat, storing the heat as latent heat to reduce indoor temperature fluctuations and peak temperatures. The summer daytime operating mode of this design is as follows: Figure 6 As shown;

[0062] The nighttime operation mode is as follows: The controller 13 opens the air inlet 7, air outlet 8, and fan 10, and opens the baffle in front of the air outlet 8, forming an open directional ventilation channel. The fan 10 is driven by the electrical energy stored in the solar storage battery 11 during the day. The temperature control component detects the air temperature inside the factory and the outdoor ambient air temperature. If the air temperature inside the factory is lower than the outdoor ambient air temperature, the electric damper 9 at branch pipe C and air supply pipe A is opened, and the electric damper 9 at branch pipe D is closed, thus introducing the exhaust air from the factory into the ventilation layer 3 for ventilation. If the outdoor air temperature is lower than the air temperature inside the factory, the electric damper 9 at branch pipe D and air supply pipe A is opened, and the electric damper 9 at branch pipe C is closed, introducing outdoor air into the ventilation layer 3 for ventilation and heat dissipation, carrying away the heat released by the condensation of the second phase change layer 4 and the third phase change layer 5. This solves the problem of ineffective heat dissipation due to small day-night temperature differences in hot summer and cold winter regions, indirectly improving its daytime insulation effect. The nighttime operation mode of this design is as follows: Figure 7 As shown;

[0063] In winter, the controller 13 keeps the air inlet 7, air outlet 8, and all electric air valves 9 closed, and slides down the baffle in front of the air outlet 8 to block it, so that the ventilation layer 3 is always in a closed state. Natural ventilation is carried out using the ventilation skylight, and the exhausted air directly enters the atmosphere. Due to the low temperature in winter, the third phase change layer 5 and the second phase change layer 4 will not undergo phase change, ensuring a small heat dissipation from the roof with a low thermal conductivity. In winter, the outdoor ambient temperature is always lower than the indoor temperature of the factory. Therefore, when heat is transferred from the inside to the outside of the factory, the first phase change layer 1 melts and absorbs heat to store some latent heat. When the temperature inside the factory is lower than the solidification phase change temperature of the first phase change layer 1, the first phase change layer 1 solidifies and releases heat, dissipating the heat into the factory to increase the temperature inside the factory. The operating mode of this invention in winter is as follows. Figure 8 and Figure 9 As shown.

[0064] The above-disclosed embodiments are merely preferred embodiments of the present invention. However, the embodiments of the present invention are not limited thereto, and any variations that can be conceived by those skilled in the art should fall within the protection scope of the present invention.

Claims

1. A ventilated, heat-insulating roof, characterized in that, include: The roof structure includes multiple phase change layers arranged sequentially from the inside to the outside. The phase change temperature of the multiple phase change layers increases sequentially from the inside to the outside. A structural layer (2) and a ventilation layer (3) are provided between the phase change layer near the inside of the roof and its adjacent phase change layer. The ventilation layer (3) is located on the outside of the structural layer (2). A ventilation skylight (14) is provided at the top of the roof structure. The ventilation layer (3) includes multiple air ducts (15) arranged side by side along the length of the roof. An air inlet (7) is provided on the side of the air duct (15) near the ventilation skylight (14). An air outlet (8) is provided on the side of the air duct (15) away from the ventilation skylight (14). A blower mechanism is installed on the roof. The input end of the blower mechanism is connected to the outside, and the output end of the blower mechanism is connected to the air inlet (7) to introduce air into the ventilation layer (3) for heat dissipation. An opening and closing mechanism is provided at the air outlet (8) for opening or closing the air outlet (8).

2. The ventilated, heat-insulating roof according to claim 1, characterized in that, There are three phase change layers, namely a first phase change layer (1), a second phase change layer (4) and a third phase change layer (5) arranged sequentially from the inside to the outside. The structural layer (2) is arranged outside the first phase change layer (1), and the ventilation layer (3) is arranged between the structural layer (2) and the second phase change layer (4). The phase change temperature range of the first phase change layer (1) is 8℃~11℃, the phase change temperature range of the second phase change layer (4) is 32℃~36℃, and the phase change temperature range of the third phase change layer (5) is 37℃~41℃.

3. A ventilated, heat-insulating roof according to claim 2, characterized in that, The phase transition temperature of the first phase transition layer (1) is 10°C, the phase transition temperature of the second phase transition layer (4) is 35°C, and the phase transition temperature of the third phase transition layer (5) is 39°C.

4. A ventilated, heat-insulating roof according to claim 3, characterized in that, The phase change material of the first phase change layer (1) is 15# paraffin wax, the phase change material of the second phase change layer (4) includes lauric acid and myristica fragrans, the mass ratio of lauric acid and myristica fragrans is 70:30, and the phase change material of the third phase change layer (5) includes lauric acid and stearic acid, the mass ratio of lauric acid and stearic acid is 82:

18.

5. A ventilated, heat-insulating roof according to claim 3, characterized in that, The blower mechanism includes a blower (10), a Y-shaped tee pipe and an air supply pipe A. The air inlet of the blower (10) is connected to the branch pipe B in the Y-shaped tee pipe. The branch pipe C in the Y-shaped tee pipe is connected to the ventilation skylight (14). The branch pipe D in the Y-shaped tee pipe is connected to the outside air. The air outlet of the blower (10) is connected to the air supply pipe A. The side wall of the air supply pipe A is connected to each air duct (15). Electric air valves (9) are provided in the air supply pipe A, branch pipe C and branch pipe D.

6. A ventilated, heat-insulating roof according to claim 5, characterized in that, The opening and closing mechanism includes a baffle (16) that can slide up and down at the air outlet (8), and the baffle (16) is controlled to slide up and down by a lifting component.

7. A ventilated, heat-insulating roof according to claim 6, characterized in that, It also includes a temperature control component, which is electrically connected to the electric air valve (9), the fan (10), and the lifting component, respectively, for controlling the opening and closing of the blower mechanism and the opening and closing mechanism according to different ambient temperatures. The temperature control component includes: Two temperature sensors are respectively installed at the inlet ends of branch pipe C and branch pipe D; The controller (13) is electrically connected to each of the temperature sensors, each electric air valve (9), the fan (10), and the lifting assembly, respectively; The solar photovoltaic power generation system is electrically connected to the controller (13).

8. A ventilated, heat-insulating roof according to claim 7, characterized in that, The solar photovoltaic power generation system includes multiple solar panels (12) and a solar battery (11). The multiple solar panels (12) are laid on the ventilation skylight (14) to convert solar energy into electrical energy. The solar battery (11) is electrically connected to the multiple solar panels (12) to receive and store the electrical energy transmitted by the solar panels (12). The controller (13) is electrically connected to the solar battery (11).

9. A ventilated, heat-insulating roof according to claim 8, characterized in that, It also includes a reflective coating layer (6), which is disposed outside the outermost phase change layer.

10. A method for controlling ventilation, heat insulation, and thermal insulation of a roof, characterized in that, The control method is applied to the ventilated, thermally insulated roof according to any one of claims 8-9, and the control method includes the following steps: Under summer operating conditions, the environment of the phase change ventilation and thermal insulation roof is determined to be either daytime or nighttime. If it is daytime, the roof will enter daytime operation mode; if it is nighttime, the roof will enter nighttime operation mode. The daytime operation mode is as follows: the controller (13) controls the air inlet (7), air outlet (8) and each electric air valve (9) to be closed, and slides down the baffle in front of the air outlet (8) to block the air outlet (8), so that the ventilation layer (3) is closed. The solar panel (12) converts solar energy into electrical energy and stores it in the solar battery (11). The controller (13) controls its charging. The ventilation skylight (14) is used for natural ventilation. The exhaust air does not enter the ventilation layer (3) but directly enters the atmosphere. When the outside temperature reaches the phase change temperature of the second phase change layer (4) and the third phase change layer (5), the second phase change layer (4) and the third phase change layer (5) melt and absorb heat and store the heat in the form of latent heat to reduce indoor temperature fluctuations and peak temperatures. The nighttime operation mode is as follows: the air inlet (7), air outlet (8), and fan (10) are opened by the controller (13), and the baffle in front of the air outlet (8) is opened to form an open directional ventilation channel. The fan (10) is driven by the electrical energy stored in the solar storage battery (11) during the day. The air temperature inside the factory and the outdoor ambient air temperature are detected by the temperature control component. If the air temperature inside the factory is lower than the outdoor ambient air temperature, the electric air valve (9) at branch pipe C and air supply pipe A is opened, and the valve at branch pipe D is closed. The electric air valve (9) is used to introduce the air discharged from the factory into the ventilation layer (3) for ventilation. If the outdoor air temperature is lower than the indoor air temperature, the electric air valve (9) at branch pipe D and air supply pipe A is opened and the electric air valve (9) at branch pipe C is closed to introduce outdoor air into the ventilation layer (3) for ventilation and heat dissipation, and to remove the heat released by the condensation of the second phase change layer (4) and the third phase change layer (5), thereby solving the problem that the small temperature difference between day and night in hot summer and cold winter regions cannot effectively dissipate heat, and indirectly improving its heat insulation effect during the day. In winter, the air inlet (7), air outlet (8) and each electric air valve (9) are controlled to be closed by the controller (13), and the baffle in front of the air outlet (8) is slid down to block the air outlet (8), so that the ventilation layer (3) is always in a closed state. Natural ventilation is carried out by the ventilation skylight, and the exhaust air directly enters the atmosphere. Due to the low temperature in winter, the third phase change layer (5) and the second phase change layer (4) will not undergo phase change, and the small thermal conductivity ensures a small heat dissipation of the roof. In winter, the outdoor ambient temperature is always lower than the indoor temperature of the factory. Therefore, when the heat in the factory is transferred from the inside to the outside, the first phase change layer (1) melts and absorbs heat to store a part of the latent heat. When the temperature in the factory is lower than the solidification phase change temperature of the first phase change layer (1), the first phase change layer (1) solidifies and releases heat, dissipating the heat into the factory to increase the temperature inside the factory.

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