Novel sine corrugated solar air collector

Abstract

The utility model discloses a novel sine corrugated solar air heat collector which comprises a heat collector body, and a heat preservation layer is arranged on the outer wall of the heat collector body. The double-layer vacuum glass cover plate is detachably connected to the top of the heat collector main body; the sine type corrugated heat absorbing plate is fixed in the heat collector main body, the sine type corrugated heat absorbing plate is internally divided into an upper heat collecting cavity and a lower heat collecting cavity by the sine type corrugated heat absorbing plate, a heat absorbing layer is plated on the top surface of the sine type corrugated heat absorbing plate, and an air inlet and an air outlet are respectively formed in two opposite side surfaces of the heat collector main body; a plurality of baffle plates are arranged on the top face and the bottom face of the sine type corrugated heat absorption plate in the gas circulation direction respectively, a snakelike flow channel is formed among the baffle plates, and the gas inlet and the gas outlet are communicated with the two ends of the snakelike flow channel respectively. The corrugated heat absorption plate is adopted, air convection can be increased, a temperature dead zone is broken, and the convection heat exchange intensity between air and the heat absorption plate is enhanced.

Description

Technical Field

[0001] The utility model relates to the technical field of solar thermal utilization, in particular to a novel sinusoidal corrugated solar air collector. Background Art

[0002] A solar air collector is a solar heating device that uses air as a heat medium and is widely used in solar heating, ventilation, dehumidification, and other fields. The most commonly used structure is the flat-plate solar air collector. Compared with vacuum tube solar collectors, it has advantages such as simple structure, low sealing requirements, and no need for antifreeze. However, it also has disadvantages such as low heat collection efficiency and high heat loss. How to further improve the heat collection efficiency of flat-plate solar air collectors has long been a goal pursued by researchers.

[0003] As a key component of a solar air collector, the performance of the absorber plate is directly related to solar energy utilization efficiency and system stability. In the paper "Design and Research of a Serpentine Double-Flow-Path Flat-Plate Solar Air Collector," the paper provides an in-depth analysis of the current state of solar air collector research. Traditional solar air collectors suffer from low heat transfer coefficients, high ambient heat losses, and low heat collection efficiency. Consequently, the design of the collector plate has been continuously refined and improved. Various types of collector plates are used to increase the heat transfer area and improve the heat transfer coefficient, thereby significantly improving heat collection efficiency. Due to weather fluctuations, solar energy is unstable, making it difficult to guarantee continuous heating in solar air collectors. Therefore, researchers are exploring heat storage technologies for solar collectors. These technologies store solar energy during clear weather for use on cloudy days or at night. However, the poor heat transfer and energy storage performance of air results in low heat collection efficiency during operation. To significantly improve this efficiency, researchers at home and abroad have conducted extensive improvements to the collector's internal flow paths and conducted experimental research. Karim Md Azharul et al. conducted experimental and theoretical studies on three types of solar air thermal collectors: flat-plate, finned, and V-shaped. They also tested the performance of these three types of collectors under single and dual flow channels and found that the V-type had the highest heat collection efficiency, followed by the finned type. Lü Kun developed a cylindrical array solar air thermal collector, adding a matrix of metal cylinders to the collector plate. This method enhances the ability to absorb solar radiation and the heat exchange between the plate and the air. Experimental studies have shown that this method can improve the heat collection efficiency of solar air thermal collectors. As discussed above, regardless of the form of solar thermal collectors designed by domestic and foreign researchers, the goal is to increase the heat exchange area within the collector and reduce heat loss, thereby improving the collector's thermal efficiency. The main methods used include improving the form or structure of the air flow channels within the collector, with parameters such as channel height, channel spacing, and air flow rate. However, most of the solar air collectors currently on the market are flat-plate collectors with poor heat collection effect. Based on this, the utility model provides a novel sinusoidal corrugated solar air collector. Utility Model Content

[0004] The purpose of the utility model is to provide a novel sinusoidal corrugated solar air collector to solve the problems existing in the prior art.

[0005] To achieve the above objectives, the present invention provides the following solutions: The present invention provides a novel sinusoidal corrugated solar air collector, comprising:

[0006] A heat collector body, wherein the outer wall of the heat collector body is provided with a heat insulation layer;

[0007] A double-layer vacuum glass cover plate, wherein the double-layer vacuum glass cover plate is detachably connected to the top of the collector body;

[0008] A sinusoidal corrugated heat absorbing plate, the sinusoidal corrugated heat absorbing plate being fixed within the collector body and arranged corresponding to the double-layer vacuum glass cover plate, the sinusoidal corrugated heat absorbing plate dividing the interior of the sinusoidal corrugated heat absorbing plate into an upper heat collecting chamber and a lower heat collecting chamber, the top surface of the sinusoidal corrugated heat absorbing plate being plated with a heat absorbing layer, an air inlet and an air outlet being respectively provided on opposite sides of the collector body, the upper heat collecting chamber and the lower heat collecting chamber being both in communication with the air inlet and the air outlet;

[0009] Among them, the top and bottom surfaces of the sinusoidal corrugated heat absorbing plate are respectively provided with a plurality of baffles along the gas flow direction, a serpentine flow channel is formed between the baffles, and the air inlet and the air outlet are respectively connected to the two ends of the serpentine flow channel.

[0010] According to the novel sinusoidal corrugated solar air collector provided by the utility model, the collector body has a length×width×height of 2000mm×1000mm×85mm.

[0011] According to the novel sinusoidal corrugated solar air collector provided by the utility model, the thickness of the double-layer vacuum glass cover is 3mm-5mm.

[0012] According to the novel sinusoidal corrugated solar air collector provided by the present invention, the number of bends of the serpentine flow channel is 25 groups, the spacing between adjacent baffles is 80 mm, and the width of the serpentine flow channel is 40 mm.

[0013] According to the novel sinusoidal corrugated solar air collector provided by the utility model, the thickness of the thermal insulation layer is 30mm-50mm.

[0014] According to the novel sinusoidal corrugated solar air collector provided by the utility model, the thermal insulation layer includes a rock wool layer, a glass wool layer, and a polystyrene layer.

[0015] According to the novel sinusoidal corrugated solar air collector provided by the utility model, the heat absorption layer is a black chrome plating layer.

[0016] The utility model discloses the following technical effects:

[0017] (1) Reduce equipment maintenance costs: Compared with traditional solar water heaters that use water as the heat transfer medium, the working medium of solar air collectors is air. Not only will there be no problems such as corrosion of pipes and collector plates, but also there will be no phenomenon of scale forming in the pipes after long-term use, which increases the flow resistance of water flow and thus reduces the heat collection efficiency. This reduces losses and maintenance costs.

[0018] (2) Improve heat exchange efficiency: Based on the characteristics of air's low heat capacity and easy heating, the use of corrugated heat absorbing plates can increase air convection, break the temperature dead zone, and enhance the convective heat exchange intensity between the air and the heat absorbing plates. At the same time, the use of serpentine flow channels prolongs the time the air stays in the heat collecting device, thereby increasing the heat exchange time between the corrugated heat absorbing plates and the air, which can significantly increase the air heat collection efficiency.

[0019] (3) Reduce heat loss during heat exchange: To achieve better heat collection and insulation, we wrap the collector with glass wool. We also install a double-layer glass cover above the heat absorbing plate and vacuum-treat the interlayer to further reduce heat exchange between the air inside the collector and the outside. Compared with traditional solar air collectors, this system is better at reducing heat loss due to heat conduction between the glass and the air.

[0020] (4) Smaller footprint: The use of sinusoidal corrugated plates can reduce the space occupied while absorbing the same amount of heat. The reduced floor space can be used for other purposes, such as agriculture, construction, etc., thereby improving land use efficiency. A smaller footprint also means that the device is easier to install and maintain, and the construction and maintenance costs are correspondingly reduced. This allows solar corrugated collectors to be applied in more scenarios to promote the popularization and promotion of renewable energy. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0022] Figure 1 This is a schematic diagram of the structure of the sinusoidal corrugated solar air collector of the utility model.

[0023] Figure 2 This is a schematic structural diagram of the double-layer vacuum glass cover of the utility model;

[0024] Figure 3 This is a schematic diagram of the arrangement structure of the baffles of the utility model.

[0025] Among them, 1. Collector body; 2. Insulation layer; 3. Double-layer vacuum glass cover; 4. Sinusoidal corrugated heat absorption plate; 5. Baffle; 6. Serpentine flow channel. DETAILED DESCRIPTION

[0026] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0027] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below with reference to the accompanying drawings and specific implementation methods.

[0028] Reference Figure 1-Figure 3 The utility model provides a novel sinusoidal corrugated solar air collector, comprising:

[0029] The heat collector body 1 has an outer wall provided with a heat-insulating layer 2;

[0030] A double-layer vacuum glass cover plate 3 is detachably connected to the top of the collector body 1;

[0031] The sinusoidal corrugated heat absorbing plate 4 is fixed in the collector body 1 and is arranged corresponding to the double-layer vacuum glass cover plate 3. The sinusoidal corrugated heat absorbing plate 4 divides the interior of the sinusoidal corrugated heat absorbing plate 4 into an upper heat collecting cavity and a lower heat collecting cavity. The top surface of the sinusoidal corrugated heat absorbing plate 4 is coated with a heat absorbing layer. The collector body 1 is provided with an air inlet and an air outlet on two opposite sides. The upper heat collecting cavity and the lower heat collecting cavity are both connected to the air inlet and the air outlet.

[0032] Among them, a number of baffles 5 are respectively provided on the top and bottom surfaces of the sinusoidal corrugated heat absorbing plate 4 along the gas flow direction, a serpentine flow channel 6 is formed between the baffles 5, and the air inlet and the air outlet are respectively connected to the two ends of the serpentine flow channel 6.

[0033] During operation, sunlight first shines through the double-layer vacuum glass panels onto the upper surface of the corrugated heat absorbing plate, raising the plate's temperature. The heat pump then pumps indoor air into the collector through an air inlet duct connected to the room. After entering the collector's upper and lower dual flow channels, the air flows along a path defined by baffles 5, passing through the upper and lower surfaces of the sinusoidal collector, exchanging heat with the heat absorbing plate, thereby raising the air temperature.

[0034] To maximize the solar-to-heat conversion efficiency of a sinusoidal solar collector, we designed the panel with a sinusoidal waveform with an amplitude period of T = 30 and an amplitude of 10 mm. The panel, with an area of 2 m², is coated with a black chrome selective absorption layer (absorptivity 0.94 ± 0.02, emissivity 0.10 ± 0.02). This selective coating can be applied by spraying, vacuum evaporation, or magnetron sputtering, with magnetron sputtering providing the best results. These coatings, applied to a copper substrate, are highly durable, resistant to high temperatures, and maintain stable physical properties under a variety of environmental conditions, making them suitable for long-term solar collector applications.

[0035] According to the further optimization plan, the collector body 1 has a length × width × height of 2000mm × 1000mm × 85mm.

[0036] According to a further optimized solution, the thickness of the double-layer vacuum glass cover plate 3 is 3 mm to 5 mm.

[0037] First, sunlight shines through the double-layer vacuum glass plate onto the upper surface of the corrugated heat absorbing plate, causing the temperature of the collector heat absorbing plate to rise.

[0038] When there is a temperature difference between the two sides of tempered vacuum glass, heat will transfer from the higher temperature side to the lower temperature side. During this heat transfer process, there is heat radiation from the inner surfaces of the two glass panels, heat is also transferred in the sealing material area, and residual gas can also conduct heat. These physical processes of heat transfer occur simultaneously. The core advantage of vacuum glass panels lies in their low thermal conductivity. Because the vacuum layer between the two layers of glass almost completely eliminates heat conduction and convection, the speed of heat transfer from one side to the other is significantly reduced. When the pressure in the vacuum layer of tempered vacuum glass is less than 10^-2Pa, the heat transfer of residual gas can be ignored. Therefore, compared with single-layer glass panels, this design can greatly reduce the heat loss during the heat collection process caused by heat conduction.

[0039] The sinusoidal corrugated heat absorbing plate 4 comprises a plate body and protrusions respectively arranged on the top and bottom of the plate body. The protrusions are arranged in a sinusoidal corrugated structure along the gas flow direction.

[0040] Vacuumed glass panels have high light transmittance because the vacuum layer has an extremely low gas content, which greatly reduces scattering and absorption. This allows the vacuumed glass panels to maintain high thermal insulation performance while also allowing solar radiation to penetrate the vacuum layer at a very high rate, allowing the solar radiation incident on the glass to reach the solar collector to the greatest extent possible.

[0041] Furthermore, vacuum glass panels have high design parameters and can withstand large temperature fluctuations and wind pressure, are not easily deformed or damaged, and have a good long-term service life. Vacuum glass is usually made of tempered glass, which has good toughness and high strength. Even if it breaks, it is unlikely to form sharp fragments, reducing damage to other decorative components.

[0042] The fan pumps the indoor air into the collector through the indoor air inlet duct. After entering the upper and lower double flow channels in the collector, the air flows along the route divided by the baffle 5, flows through the upper and back surfaces of the sinusoidal collector, and exchanges heat with the heat absorbing plate, thereby increasing the air temperature.

[0043] The sinusoidal heat-absorbing plate used in this device increases air convection, breaks the temperature dead zone, reduces energy loss, and thus improves the heat collection performance of the solar air collector. When air flows over the raised structures, boundary layer separation occurs. The separated flow then reattaches to the channel wall, forming a new developing boundary layer. This reattachment and circulation phenomenon repeatedly occurs near the raised structures, thus achieving the local heat transfer enhancement effect of the raised structures. Therefore, the average Nu of the heat-absorbing plate surface with raised structures is higher than the average Nu of the smooth heat-absorbing surface. At the same time, the corrugated arrangement of the raised structures creates secondary flow and recirculation zones when air flows through the gaps between the raised structures, and the airflow reattaches again in the space between the two raised structures. The frequent separation and reattachment of the airflow disrupts the growth of the laminar bottom layer, enhances flow mixing, and thus improves the heat transfer rate.

[0044] The Nu of the surface of a heat-absorbing plate with a sinusoidal corrugated raised structure is significantly improved compared to a smooth heat-absorbing plate. This is because the raised structure destroys the laminar bottom layer of the wall, increases the turbulence of the fluid, and improves the convective heat transfer coefficient between the fluid and the wall. The increase in Re, while increasing the turbulence of the fluid, also delays the position where the fluid separates from the curved surface, reducing the range of the wake zone. In addition, the vortex intensity inside the air flow channel is also enhanced by the increase in Re. The vortex will further strengthen the turbulence effect, reducing the low heat transfer area, so that Nu increases with the increase of Reynolds number. In addition, the use of a sinusoidal wave plate heat-absorbing plate can also help improve the efficiency of solar energy utilization and reduce the pressure loss when air flows through the heat-absorbing plate. Cheng Youliang and others compared the sinusoidal corrugated heat absorbing plate with traditional flat plate and triangular corrugated heat absorbing plate through CFD software simulation. The sinusoidal corrugated plate structure has the highest solar energy utilization efficiency, followed by the triangular corrugated heat absorbing plate air collector, and the pressure loss of the sinusoidal corrugated plate structure is less than that of the triangular corrugated heat absorbing plate structure; finally, the heated air can be sent into the room for heating. In addition, the corrugated solar air collector can also be equipped with a dryer or humidifier at the end of the collector to dry or humidify the air to meet the different air needs of residential buildings in the north and south.

[0045] According to a further optimized solution, the number of bends of the serpentine flow channel 6 is 25 groups, the spacing between adjacent baffles 5 is 80 mm, and the width of the serpentine flow channel 6 is 40 mm.

[0046] Conventional flat-plate solar air collectors without spoilers have internal air vortices that easily form dead zones, leading to local overheating and air stagnation. Furthermore, the air stays inside the collector for a long time, which reduces collector performance. Therefore, the present invention designs the internal spoiler of the collector into a serpentine air duct, which reduces the internal air flow dead zones and increases the heat exchange time between the air and the heat absorbing plate, thereby improving collector performance. The use of serpentine air ducts can significantly increase air heat collection efficiency.

[0047] According to the further optimized solution, the thickness of the thermal insulation layer 2 is 30mm-50mm.

[0048] According to a further optimization scheme, the thermal insulation layer 2 includes a rock wool layer, a glass wool layer, and a polystyrene layer.

[0049] To further optimize the solution, the heat absorbing layer is a black chrome plating layer.

[0050] In the description of the present invention, it should be understood that the terms "longitudinal", "transverse", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating the orientation or position relationship, are based on the orientation or position relationship shown in the accompanying drawings, and are only for the convenience of describing the present invention, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, they should not be understood as limitations on the present invention.

[0051] The embodiments described above are merely preferred embodiments of the present invention and are not intended to limit the scope of the present invention. Without departing from the spirit of the present invention, various modifications and improvements to the technical solutions of the present invention made by ordinary technicians in this field should fall within the scope of protection determined by the claims of the present invention.

Claims

1. A novel sinusoidal corrugated solar air collector, characterized in that: include: A heat collector body (1), wherein the outer wall of the heat collector body (1) is provided with a heat insulation layer (2); a double-layer vacuum glass cover plate (3), the double-layer vacuum glass cover plate (3) being detachably connected to the top of the heat collector body (1); A sinusoidal corrugated heat absorbing plate (4), the sinusoidal corrugated heat absorbing plate (4) is fixed in the heat collector body (1) and is arranged corresponding to the double-layer vacuum glass cover plate (3), the sinusoidal corrugated heat absorbing plate (4) divides the sinusoidal corrugated heat absorbing plate (4) into an upper heat collecting cavity and a lower heat collecting cavity, the top surface of the sinusoidal corrugated heat absorbing plate (4) is plated with a heat absorbing layer, the heat collector body (1) is provided with an air inlet and an air outlet on two opposite side surfaces, and the upper heat collecting cavity and the lower heat collecting cavity are both connected to the air inlet and the air outlet; A plurality of baffles (5) are provided on the top and bottom surfaces of the sinusoidal corrugated heat absorbing plate (4) along the gas flow direction, a serpentine flow channel (6) is formed between the baffles (5), and the air inlet and the air outlet are respectively connected to the two ends of the serpentine flow channel (6).

2. A novel sinusoidal corrugated solar air collector according to claim 1, characterized in that: The heat collector body (1) has a length×width×height of 2000mm×1000mm×85mm.

3. The novel sinusoidal corrugated solar air collector according to claim 1 is characterized by: The thickness of the double-layer vacuum glass cover plate (3) is 3 mm to 5 mm.

4. The novel sinusoidal corrugated solar air collector according to claim 1 is characterized by: The number of bends of the serpentine flow channel (6) is 25, the spacing between adjacent baffles (5) is 80 mm, and the width of the serpentine flow channel (6) is 40 mm.

5. The novel sinusoidal corrugated solar air collector according to claim 1 is characterized by: The thickness of the thermal insulation layer (2) is 30 mm to 50 mm.

6. The novel sinusoidal corrugated solar air collector according to claim 1 is characterized by: The thermal insulation layer (2) comprises a rock wool layer, a glass wool layer, and a polystyrene layer.

7. The novel sinusoidal corrugated solar air collector according to claim 1 is characterized by: The heat absorption layer is a black chromium plating layer.

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