A heat collecting plate with high energy efficiency ratio and stable operation

Abstract

The present invention relates to the field of solar panel manufacturing. The working fluid in the existing heat collecting panel is in a bottom-in and top-out working mode, resulting in uneven heat absorption, low energy efficiency ratio, and poor oil return. The present invention provides a heat collecting panel with high energy efficiency ratio and stable operation, including a panel body, wherein a working fluid flow channel is arranged in the panel body, and a working fluid inlet and a working fluid outlet respectively connected to the working fluid flow channel are arranged on the panel body, wherein the working fluid inlet is located at the top of the working fluid flow channel, and the working fluid outlet is located at the bottom of the flow channel; the heat absorption effect is balanced, the energy efficiency ratio is high, and the oil return is smooth.

Description

Technical Field

[0001] The invention relates to the field of solar heat collecting plate manufacturing, and more specifically to a heat collecting plate with high energy efficiency ratio and stable operation. Background Art

[0002] The heat collecting plate is an important component of solar heterogeneous heating equipment. Its interior is full of oil flow channels. When the working medium flows through the flow channels, the (liquid-gas) phase changes occur, thereby absorbing heat from the environment to achieve the purpose of improving energy efficiency. In the existing heat collecting plate layout structure, the flow channel usually adopts the method of oil (the liquid is the working medium, referred to as the working medium; the oil is the lubricating oil, which is used to lubricate the compressor) entering from the bottom and exiting from the top. After long-term use, it is found that the current heat collecting plate has the following defects:

[0003] 1. The bottom-in and top-out supply and return method creates a dead corner at the bottom or edge of the heat collecting plate. The oil-liquid mixed medium cannot enter this area during operation, which wastes the evaporation area of ​​the heat collecting plate, affects the heat absorption of the plate surface and thus affects the energy efficiency of the system; the evaporated gaseous medium will accumulate in the dead corner, destroying the overall pressure balance of the heat collecting plate, and in severe cases, causing local cracking of the heat collecting plate.

[0004] 2. The oil and the working fluid are in a miscible state. As the working fluid temperature drops, the solubility of the oil will be greatly reduced. The working fluid will be separated into oil and liquid in the heat collecting plate. The separated oil cannot evaporate and naturally sinks under the influence of gravity. The bottom-in and top-out heat collecting plate cannot take away the accumulated oil at the bottom. Long-term accumulation and poor oil return will lead to oil shortage in the system, which will in turn affect the life of the compressor. Without oil sealing of mechanical equipment, the system efficiency will be greatly reduced.

[0005] Especially in extremely cold working conditions, the poor oil return is aggravated. For example, at -10 degrees Celsius to -30 degrees Celsius, the ambient temperature is closer to the boiling point of the working fluid. The smaller the difference between the ambient temperature and the boiling point of the working fluid, the milder the phase change of the working fluid in the flow channel. When the working fluid is converted from liquid to gas, its volume will expand. The expanded gaseous working fluid can also carry some lubricating oil when it returns from the flow channel through the upper outlet. The mild phase change will cause the activity of the gaseous working fluid to weaken, and its ability to return oil will be further weakened, or even completely lost. After working in extremely cold conditions for a long time, the lubricating oil will continue to accumulate in the flow channel (at the bottom or edge of the heat collecting plate). Eventually, the compressor will malfunction due to lack of lubricating oil and will not be able to work.

[0006] 3. In addition, when the ambient temperature of extremely cold working conditions is close to the boiling point of the working fluid, on the one hand, the liquid working fluid cannot obtain enough heat and cannot be completely evaporated into a gaseous working fluid. As the operating time goes by, the liquid working fluid will accumulate at the bottom of the heat collecting plate, and even the entire plate surface will become a "liquid storage tank", causing the working system where the heat collecting plate is located to appear to be "lack of working fluid", causing the compressor in the system to have high temperature, and in severe cases, the compressor will be burned.

[0007] 4. On the other hand, the liquid working medium enters from the bottom of the heat collecting plate. Since it cannot get enough heat to evaporate into gas, the liquid working medium is greatly affected by gravity, which will hinder the return air of the compressor, greatly increase the resistance of the system in the heat collecting plate part, increase the power consumption of the compressor and reduce the energy efficiency ratio. Summary of the invention

[0008] The technical problem to be solved by the present invention is to overcome the defects existing in the above-mentioned prior art and provide a heat collecting plate with high energy efficiency ratio and stable operation.

[0009] To achieve the above-mentioned purpose, the present invention is implemented through the following technical scheme: a heat collecting plate with high energy efficiency ratio and stable operation, comprising a panel body, a working fluid flow channel is provided in the panel body, and a working fluid inlet and a working fluid outlet respectively connected to the working fluid flow channel are provided on the panel body, the working fluid inlet is located at the top of the working fluid flow channel, and the working fluid outlet is located at the bottom of the flow channel.

[0010] In the above technical solution, the flow path is set from top to bottom, and the liquid working medium flows in the flow channel under the impetus of gravity, converting gravity into a part of the flow power of the liquid working medium, reducing the system resistance, reducing the power consumption of the compressor and thus improving energy efficiency. After the oil and liquid are separated, the oil is naturally deposited to the lowest point of the heat collecting plate under the influence of gravity, and can smoothly return to the compressor through the slightly inclined oil return pipe, ensuring the life and efficiency of the compressor and improving working stability.

[0011] A further preferred solution of the present invention is: the working fluid flow channel is divided into zones to form a plurality of evaporation zones connected end to end, and the plurality of evaporation zones are arranged from top to bottom; the working fluid inlet is located in the uppermost evaporation zone, and the working fluid outlet is located in the lowermost evaporation zone. The oil (mixed) working fluid maintains a high-speed, pressurized liquid phase flow form before entering the heat collecting plate. After entering the heat collecting plate, the space suddenly expands, the flow rate of the oil working fluid slows down, the oil working fluid is released and begins to evaporate. The lubricating oil is deposited by gravity, and the liquid working fluid is converted into a gaseous state in the process of passing through each evaporation zone in sequence under the push of gravity.

[0012] A further preferred solution of the present invention is that a plurality of barrier parts are provided in the panel body, and the barrier parts divide the working medium flow channel into a plurality of evaporation zones.

[0013] A further preferred solution of the present invention is that a balance pipe for guiding the gaseous working medium is provided on one side of the evaporation zone, and the balance pipe on the side of the lowest evaporation zone is connected to the working medium outlet. The evaporated gaseous working medium is led away from the balance pipe to achieve the purpose of gas-liquid separation and pressure balance, completely solving the problem of "evaporation dead corner" and "local expansion and cracking" caused by pressure imbalance, increasing the evaporation area, balancing the plate surface temperature, and improving the reliability and life of the heat collecting plate.

[0014] A further preferred solution of the present invention is that two adjacent evaporation zones are connected at the end or corner of the barrier; a diversion portion for destroying the blind spot of the evaporation zone is provided at the end or corner of the barrier, and a gap is provided between the diversion portion and the barrier. This can completely destroy the dead zone where the oil or gaseous working medium accumulates and does not flow, and balance the pressure of the entire plate, which is a guarantee for uniform evaporation of the heat collecting plate.

[0015] A further preferred solution of the present invention is that an oil return pipe is further provided on the panel body, the oil return pipe is located at the bottom of the lowest evaporation zone, and one end of the oil return pipe is connected to the working medium outlet.

[0016] A further preferred solution of the present invention is that one end of the oil return pipe is arranged to be tilted downward, and the downward tilted end is connected to the working medium outlet.

[0017] A further preferred solution of the present invention is that a flow extension portion for conveying the liquid working medium in a horizontal direction is provided in the evaporation zone.

[0018] A further preferred solution of the present invention is that: in each layer of evaporation zone on the panel body, from the first layer to the second layer from top to bottom, the area of ​​two adjacent layers of evaporation zone is greater than or equal to 1; the area of ​​the evaporation zone at the bottom layer is greater than the area of ​​the evaporation zone at the second to last layer. The flow direction and area ratio are designed according to the evaporation law to ensure that the liquid working medium is fully evaporated.

[0019] In summary, the present invention has the following beneficial effects: the overall structure of the working fluid flow channel in the panel body adopts a top-in and bottom-out method, the working fluid enters from the upper part of the panel body, and moves horizontally under the influence of gravity and inertia while the liquid working fluid naturally settles. The evaporated gaseous working fluid at this stage is pulled by the suction of the working fluid outlet of the panel body and sucked away from the balance pipe, avoiding the formation of an evaporation blind spot, making the liquid separation more uniform and absorbing heat more fully. After passing through several evaporation zones, the working fluid is discharged from the lowest point of the heat collecting plate, the working fluid flow path is unobstructed, and the liquid working fluid flow does not need to overcome gravity, which reduces the system operation resistance and the power consumption of the compressor, thereby improving the energy efficiency ratio. A slightly inclined oil return pipe is provided at the lowest point of the evaporation zone, and the oil return is unobstructed. There is no possibility of oil accumulation on the heat collecting plate, which can extend the service life of the compressor in the working system where the heat collecting plate is located. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 It is a structural schematic diagram of Example 1.

[0021] Figure 2 This is a stereogram of Example 1.

[0022] Figure 3 yes Figure 1 Enlarged view of point A in the middle.

[0023] Figure 4 yes Figure 1Enlarged view of point B in the middle.

[0024] Figure 5 It is a structural schematic diagram of Example 2.

[0025] In the figure: 1. working fluid inlet; 2. evaporation area; 3. balance pipeline; 4. diversion part; 5. oil return pipe; 6. working fluid outlet; 7. barrier part; 8. flow extension part. DETAILED DESCRIPTION

[0026] The present invention is further described in detail below in conjunction with the accompanying drawings.

[0027] This embodiment is merely an explanation of the present invention and is not a limitation of the present invention. After reading this specification, those skilled in the art may make non-creative modifications to this embodiment as needed. However, as long as they are within the scope of the claims of the present invention, they are protected by the patent law.

[0028] Embodiment 1: as Figure 1 and Figure 2 As shown, a heat collecting plate with high energy efficiency ratio and stable operation is shown, including a panel body, and a working medium flow channel distributed in a grid shape is arranged in the panel body. In this embodiment, the panel is rectangular, and the working flow channel is composed of two groups of pipes that are crisscrossed and interconnected, one group of pipes is arranged horizontally, and the other group of pipes is arranged vertically. When the panel body is in use, it is vertically arranged on the outer surface of the wall or tilted in the open air through a fixing frame (in addition, according to the actual needs, the panel can also be curved).

[0029] The panel body is also provided with a working fluid inlet 1 and a working fluid outlet 6 respectively connected to the working fluid flow channel. The working fluid inlet 1 is located at the top of the working fluid flow channel, and the working fluid outlet 6 is located at the bottom of the flow channel.

[0030] The working fluid flow channel is divided into zones to form a plurality of evaporation zones 2 connected end to end (in an S shape), and the plurality of evaporation zones 2 are arranged from top to bottom. In this embodiment, three (horizontal) barrier portions 7 are provided in the panel body, and the working fluid flow channel is divided into four evaporation zones 2 by the barrier portions 7. The barrier portions 7 are the closing points of the flow channels on the heat collecting plate, and no working fluid flow channels are provided in this area, so that the heat collecting plate achieves the purpose of functional zoning and functional diversion.

[0031] Two adjacent evaporation zones 2 are connected at the end or corner of the barrier 7. A diversion portion 4 is provided at the end or corner of the barrier 7 to destroy the blind spot of the evaporation zone 2 (see Figure 3 and 4 ), a gap is set between the diverter portion 4 and the barrier portion 7 (at least one pipe is provided between the diverter portion 4 and the barrier portion 7).

[0032] The working medium inlet 1 is located at the uppermost evaporation zone 2 , and the working medium outlet 6 is located at the lowermost evaporation zone 2 .

[0033] In the present embodiment, in each layer of evaporation zone 2 on the panel body, from the first layer to the second layer from the top, the areas of two adjacent layers of evaporation zone 2 are greater than or equal to 1 (that is, in two adjacent layers of evaporation zone 2, the area of ​​the evaporation zone 2 located in the upper layer is greater than or equal to the area of ​​the evaporation zone 2 located in the lower layer); the area of ​​the evaporation zone 2 located in the bottom layer is greater than the area of ​​the evaporation zone 2 in the second to last layer (the gaseous working fluid and liquid lubricating oil in the incompletely converted layer eventually converge in the last layer of evaporation zone 2, so sufficient area needs to be reserved).

[0034] A balance pipe 3 for guiding the gaseous working medium is provided on one side of the evaporation zone 2, and the balance pipe 3 on the side of the lowest evaporation zone 2 is connected to the working medium outlet 6. In this embodiment, the barrier 7 is L-shaped, and its horizontal portion is used to divide the working medium flow channel into a plurality of evaporation zones 2, and its vertical portion is used to divide the balance pipe 3 on one side of the evaporation zone 2. After the liquid working medium in the evaporation zone 2 is converted into gas, it is drawn out of the panel body through the lateral balance pipe 3.

[0035] The panel body is also provided with an oil return pipe 5, which is located at the bottom of the lowest evaporation zone 2. One end of the oil return pipe 5 is tilted downward, and the downward tilted end intersects with the balance pipe 3 and is connected to the working medium outlet 6. The oil separated from the working medium due to the low temperature and the enlarged space is gathered to the lowest point of the bottom evaporation zone 2 under the influence of gravity, and the oil is smoothly sent out of the working medium outlet 6 and returned to the compressor of the working system.

[0036] Embodiment 2: as Figure 5 As shown, another embodiment of a heat collecting plate with high energy efficiency ratio and stable operation is shown. The main difference between Example 2 and Example 1 is that the evaporation zone 2 in Example 2 is provided with a flow extension portion 8 for conveying liquid working medium in the horizontal direction. The flow extension portion 8 is arranged horizontally, and a plurality of flow extension portions 8 are distributed step by step in the evaporation zone 2. During operation, the liquid working medium enters from one side of the evaporation zone 2 and can spread in the horizontal direction after passing through a plurality of flow extension portions 8. The remaining features and structures are the same as those in Example 1, and will not be described in detail here.

Claims

1. A heat collecting plate with high energy efficiency and stable operation, comprising a panel body, a working fluid flow channel is arranged in the panel body, and a working fluid inlet (1) and a working fluid outlet (6) are respectively connected to the working fluid flow channel on the panel body, characterized in that: The working fluid inlet (1) is located at the top of the working fluid flow channel, and the working fluid outlet (6) is located at the bottom of the flow channel; the working fluid flow channel is divided into zones to form a plurality of evaporation zones (2) connected end to end, and the plurality of evaporation zones (2) are arranged from top to bottom; the working fluid inlet (1) is located at the top evaporation zone (2), and the working fluid outlet (6) is located at the bottom evaporation zone (2); an oil return pipe (5) is also provided on the panel body, and the oil return pipe (5) is located at the bottom of the bottom evaporation zone (2), and one end of the oil return pipe (5) is connected to the working fluid outlet (6).

2. The heat collecting plate according to claim 1, characterized in that: A plurality of barrier portions (7) are provided in the panel body, and the barrier portions (7) divide the working fluid flow channel into a plurality of evaporation zones (2).

3. The heat collecting plate according to claim 1, characterized in that: A balance pipe (3) for guiding gaseous working medium is provided on one side of the evaporation zone (2), and the balance pipe (3) located on the side of the lowest evaporation zone (2) is connected to the working medium outlet (6).

4. The heat collecting plate according to claim 2, characterized in that: Two adjacent evaporation zones (2) are connected at the end or corner of the barrier portion (7); a diversion portion (4) for destroying the blind spot of the evaporation zone (2) is provided at the end or corner of the barrier portion (7), and a gap is provided between the diversion portion (4) and the barrier portion (7).

5. The heat collecting plate according to claim 1, characterized in that: One end of the oil return pipe (5) is arranged to be tilted downward, and the downward tilted end is connected to the working medium outlet (6).

6. The heat collecting plate according to claim 1, characterized in that: The evaporation zone (2) is provided with a flow extension portion (8) for conveying liquid working medium in a horizontal direction.

7. The heat collecting plate according to claim 2, characterized in that: In each layer of evaporation zones (2) on the panel body, from the first layer to the second-to-last layer, the area ratio of two adjacent layers of evaporation zones (2) is greater than or equal to 1; the area of ​​the evaporation zone (2) at the bottom layer is greater than the area of ​​the evaporation zone (2) at the second-to-last layer.

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