Improved heat pipe type evacuated collector tube

Abstract

The utility model belongs to the technical field of solar energy, and particularly relates to an improved heat pipe type vacuum heat collecting pipe which comprises a transparent shell, a shell supporting frame, a heat collecting outer pipe, a heat collecting inner pipe and a turbulent flow pipe. A vacuum layer is arranged between the heat collection outer pipe and the heat collection inner pipe. And a selective absorbing coating is arranged on the outer wall of the heat collecting inner tube. And a getter is arranged in the vacuum layer. And a medium outlet is formed in the other end of the heat collection inner pipe. According to the improved heat pipe type vacuum heat collecting pipe, by arranging the turbulent flow pipe, disturbance of a heat transfer medium in the pipe is enhanced, the heat exchange efficiency is improved, solar radiation energy can be more sufficiently absorbed through the high-performance selective absorption coating, heat loss is reduced, the high vacuum degree of the vacuum layer is effectively maintained through the arrangement of the getter, and the service life of the vacuum layer is prolonged. And the overall structural design is reasonable, the heat exchange effect of the vacuum heat collecting pipe can be remarkably improved, and the utilization efficiency of solar energy is improved.

Description

Technical Field

[0001] This utility model belongs to the field of solar energy technology, and in particular relates to an improved heat pipe vacuum collector tube. Background Technology

[0002] Vacuum collector tubes are the core component of solar water heaters, converting solar radiation into heat and transferring it to the heat transfer medium inside the tube. However, existing vacuum collector tubes have certain shortcomings in heat exchange efficiency. For example, the relatively stable flow of the heat transfer medium inside the tube leads to low heat transfer efficiency; the performance of the selective absorption coating is not ideal, failing to fully absorb solar radiation; and residual gas in the vacuum layer also affects the heat exchange performance of the collector tube. Therefore, it is necessary to design a vacuum collector tube with better heat exchange performance to improve the utilization efficiency of solar energy. Utility Model Content

[0003] The purpose of this invention is to provide an improved heat pipe vacuum collector tube, which aims to solve the technical problems of low heat transfer efficiency, inability to fully absorb solar radiation energy, and impact on the heat preservation and heat exchange performance of the collector tube in the prior art.

[0004] To achieve the above objectives, the improved heat pipe vacuum collector tube provided in this utility model embodiment includes a transparent shell, a shell support frame, an outer heat collection tube, an inner heat collection tube, and a turbulence-disrupting tube. The shell support frame is connected to the transparent shell, the outer heat collection tube is connected to the transparent shell, the inner heat collection tube is disposed inside the outer heat collection tube and connected to the shell support frame, and the turbulence-disrupting tube is connected to the inner heat collection tube.

[0005] A vacuum layer is provided between the outer heat collection tube and the inner heat collection tube. A selective absorption coating is provided on the outer wall of the inner heat collection tube. The vacuum layer is located on one side of the selective absorption coating and contains a getter.

[0006] The outer heat collection tube is a high borosilicate glass tube, and the inner heat collection tube has a medium inlet at one end and a medium outlet at the other end.

[0007] As an optional solution of this utility model, the turbulence tube is made of a metal material with good thermal conductivity.

[0008] As an optional embodiment of this invention, the selective absorption coating has an absorption rate of more than 90% for solar radiation and an emissivity of less than 10%.

[0009] As an optional embodiment of this invention, the thickness of the selective absorption coating is 0.5-2 mm.

[0010] As an optional embodiment of this invention, the getter is a barium-titanium getter, and the getter is disposed at the end of the heat collection outer tube.

[0011] As an optional solution of this utility model, there are three heat collection tubes, all of which are fixedly connected to the transparent shell, and the three heat collection tubes are arranged in parallel and at intervals.

[0012] As an optional embodiment of this utility model, the number of the inner heat collection tube and the outer heat collection tube are both three, and one inner heat collection tube is fixedly connected inside each outer heat collection tube.

[0013] The improved heat pipe vacuum collector provided in this embodiment of the utility model has at least one of the following technical effects:

[0014] The improved heat pipe vacuum collector tube provided in this application includes a transparent shell, a shell support frame, an outer collector tube, an inner collector tube, and a turbulence-inducing tube. By setting the turbulence-inducing tube, the disturbance of the heat transfer medium inside the tube is enhanced, thereby improving the heat exchange efficiency. The high-performance selective absorption coating can more fully absorb solar radiation energy and reduce heat loss. The setting of the getter effectively maintains the high vacuum level of the vacuum layer, reducing the impact of heat conduction and heat convection. The overall structural design is reasonable and can significantly improve the heat exchange effect of the vacuum collector tube and enhance the utilization efficiency of solar energy. Attached Figure Description

[0015] To more clearly illustrate the technical solutions in the embodiments of this utility model, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0016] Figure 1 A side view of the improved heat pipe vacuum collector tube provided for an embodiment of this utility model.

[0017] Figure 2 A perspective view of the improved heat pipe vacuum collector tube provided for an embodiment of this utility model.

[0018] Figure 3 A perspective view of the improved heat pipe vacuum collector tube provided in this embodiment of the utility model, omitting the transparent shell.

[0019] Figure 4 A perspective view of the improved heat pipe vacuum collector tube provided in this embodiment of the utility model, omitting the transparent shell, outer collector tube, and inner collector tube.

[0020] The following are the labeling elements in the figure:

[0021] 1. Transparent shell; 2. Shell support frame; 3. Heat collection outer tube; 5. Baffle tube. Detailed Implementation

[0022] The embodiments of this utility model are described in detail below. Examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain the embodiments of this utility model, and should not be construed as limiting the utility model.

[0023] In the description of the embodiments of this utility model, it should be understood that the terms "length", "width", "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 drawings. They are only for the convenience of describing the embodiments of this utility model 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. Therefore, they should not be construed as limitations on this utility model.

[0024] Furthermore, 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 indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of embodiments of this utility model, "a plurality of" means two or more, unless otherwise explicitly specified.

[0025] In this embodiment of the invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this embodiment of the invention according to the specific circumstances.

[0026] In one embodiment of this utility model, such as Figures 1-4 As shown, an improved heat pipe vacuum collector tube is provided, including a transparent shell 1, a shell support frame 2, an outer collector tube 3, an inner collector tube, and a turbulence-disrupting tube 5. The shell support frame 2 is connected to the transparent shell 1, the outer collector tube 3 is connected to the transparent shell 1, the inner collector tube is disposed inside the outer collector tube 3 and connected to the shell support frame 2, and the turbulence-disrupting tube 5 is connected to the inner collector tube.

[0027] A vacuum layer is provided between the outer heat collection tube 3 and the inner heat collection tube. The outer wall of the inner heat collection tube is provided with a selective absorption coating. The vacuum layer is located on one side of the selective absorption coating and contains a getter.

[0028] The outer heat collection tube 3 is a high borosilicate glass tube, and the inner heat collection tube has a medium inlet at one end and a medium outlet at the other end.

[0029] The improved heat pipe vacuum collector tube provided in this application operates as follows:

[0030] Photothermal conversion: The transparent shell 1 allows solar radiation to pass through and irradiate the selective absorption coating on the outer wall of the inner heat collector tube. This coating has a high absorptivity and low emissivity to solar radiation, enabling it to efficiently convert solar radiation energy into heat energy.

[0031] Vacuum insulation: The vacuum layer between the outer heat collection tube 3 and the inner heat collection tube greatly reduces heat loss caused by heat conduction and heat convection, because there is almost no molecular heat transfer in the vacuum environment, effectively maintaining the heat of the inner heat collection tube.

[0032] Medium heat exchange: In the inner tube of the heat collector, the turbulence tube 5 causes disturbance to the incoming heat transfer medium, which increases the contact area and turbulence between the medium and the inner wall of the inner tube of the heat collector, thereby accelerating the speed at which heat is transferred from the inner tube of the heat collector to the heat transfer medium.

[0033] Maintaining vacuum: The getter in the vacuum layer can absorb residual or slowly released gas, continuously maintaining the high vacuum state of the vacuum layer.

[0034] effect:

[0035] High-efficiency heat collection: The design of selective absorption coating and vacuum layer allows the heat collection tube to fully absorb solar radiation energy and reduce heat loss, thus achieving high-efficiency heat collection.

[0036] Enhanced heat exchange: The turbulence tube 5 improves the heat exchange efficiency between the heat transfer medium and the heat collection inner tube, allowing the heat to be carried away by the medium more quickly for subsequent use.

[0037] Stability performance: The shell support frame 2 plays a fixing role, ensuring the relative position of each component is stable; the getter maintains the vacuum degree, ensuring that the heat collection tube maintains good heat insulation and heat collection performance for a long time.

[0038] In another embodiment of this invention, the turbulence tube 5 is made of a metal material with good thermal conductivity. The turbulence tube 5 can significantly improve the heat exchange efficiency between the heat transfer medium and the inner wall of the heat collection inner tube. More heat can be transferred from the heat collection inner tube to the heat transfer medium in a shorter time, thereby improving the heat collection performance of the entire vacuum heat collection tube.

[0039] In another embodiment of this invention, the selective absorption coating exhibits an absorptivity of greater than 90% and an emissivity of less than 10% for solar radiation. The microstructure and chemical composition of the selective absorption coating are specially designed to resonate with multiple wavelengths of solar radiation, resulting in a high absorption rate. Solar radiation encompasses a wide band, from ultraviolet to infrared. This coating can efficiently absorb solar radiation energy through mechanisms such as electron transitions and lattice vibrations, converting it into its own thermal energy. An absorptivity greater than 90% means that the vast majority of solar radiation energy is absorbed. This high absorptivity allows the vacuum collector tube to extract more energy from solar radiation, rapidly increasing the temperature of the inner tube and improving heat collection efficiency. Under the same illumination conditions, compared to coatings with lower absorptivity, it can absorb more solar radiation energy, providing a greater thermal foundation for subsequent heat transfer. Emissivity is related to the surface properties and temperature of the object. This coating reduces its own surface thermal radiation capacity, minimizing heat loss to the surrounding environment through radiation. It suppresses the coating's ability to emit infrared radiation at room temperature, resulting in an emissivity of less than 10%, thus retaining as much absorbed heat as possible. Low emissivity can effectively reduce the reverse radiation loss after the heat collector tube absorbs heat, allowing more heat to be retained in the inner tube of the collector tube to heat the heat transfer medium inside the tube, thereby improving the overall thermal performance of the collector tube and increasing energy utilization efficiency in solar energy utilization systems.

[0040] In another embodiment of this invention, the thickness of the selective absorption coating is 0.5-2 mm, preferably 1 mm. Controlling the coating thickness within the range of 0.5-2 mm ensures a high absorption rate of solar radiation. Within this thickness range, the coating can fully absorb solar radiation energy, enabling the inner heat collector tube to heat up rapidly and improving the heat collection efficiency of the tube. For example, when the thickness is 1 mm, the coating's absorption rate of solar radiation can approach the design requirement of greater than 90%, effectively converting solar energy into heat energy.

[0041] In another embodiment of this invention, the getter is a barium-titanium getter, which is disposed at the end of the outer collector tube 3. A stable vacuum environment helps improve the heat collection efficiency of the collector tube. Because a high vacuum reduces the scattering and absorption of solar radiation by the gas, more sunlight can reach the selective absorption coating of the inner collector tube. It also reduces heat loss to the outside through gas conduction, thus allowing the collector tube to more effectively convert solar energy into heat energy and retain it, thereby improving the heat collection efficiency.

[0042] In another embodiment of this utility model, three outer heat-collecting tubes 3 are provided, all fixedly connected to the transparent shell 1, and the three outer heat-collecting tubes 3 are arranged in parallel and spaced apart. The number of inner heat-collecting tubes is also three, with one inner heat-collecting tube fixedly connected inside each outer heat-collecting tube 3. By setting multiple parallel and spaced outer heat-collecting tubes 3 and their corresponding inner heat-collecting tubes, the solar radiation receiving area is increased. Each outer heat-collecting tube 3 and its internal inner heat-collecting tube form an independent heat-collecting unit, and the transparent shell 1 allows solar radiation to be evenly distributed onto each outer heat-collecting tube 3. The selective absorption coating on the outer wall of each inner heat-collecting tube absorbs solar radiation and converts it into heat energy, which is then transferred to the heat transfer medium inside the tube. Due to the parallel and spaced arrangement of the outer and inner heat-collecting tubes 3, mutual obstruction between units is avoided, ensuring that each heat-collecting unit can fully receive solar radiation, achieving simultaneous and efficient heat collection by multiple units.

[0043] The improved heat pipe vacuum collector tube provided in this application enhances the turbulence of the heat transfer medium inside the tube by setting the turbulence tube 5, thereby improving the heat exchange efficiency. The high-performance selective absorption coating can more fully absorb solar radiation energy and reduce heat loss. The setting of getter effectively maintains the high vacuum level of the vacuum layer and reduces the impact of heat conduction and heat convection. The overall structural design is reasonable and can significantly improve the heat exchange effect of the vacuum collector tube and improve the utilization efficiency of solar energy.

[0044] The above description is only a preferred embodiment of the present utility model and is not intended to limit the present utility model. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present utility model should be included within the protection scope of the present utility model.

Claims

1. An improved heat pipe evacuated tubular collector (ETC) characterized in that, It includes a transparent shell, a shell support frame, an outer heat collection tube, an inner heat collection tube, and a baffle tube. The shell support frame is connected to the transparent shell, the outer heat collection tube is connected to the transparent shell, the inner heat collection tube is disposed inside the outer heat collection tube and connected to the shell support frame, and the baffle tube is connected to the inner heat collection tube. A vacuum layer is provided between the outer heat collection tube and the inner heat collection tube. A selective absorption coating is provided on the outer wall of the inner heat collection tube. The vacuum layer is located on one side of the selective absorption coating and contains a getter. The outer heat collection tube is a high borosilicate glass tube, and the inner heat collection tube has a medium inlet at one end and a medium outlet at the other end.

2. The improved evacuated tubular collector (10) of claim 1, wherein The baffle tube is made of a metal material with good thermal conductivity.

3. The improved thermal graded vacuum collector tube according to claim 1, wherein, The selective absorption coating has an absorption rate of more than 90% for solar radiation and an emissivity of less than 10%.

4. An improved evacuated tubular collector (1) according to claim 1 or 3, characterized in that The thickness of the selective absorption coating is 0.5-2 mm.

5. An improved heat pipe type vacuum collector tube according to claim 1, characterized in that, The getter is a barium-titanium getter, and the getter is disposed at the end of the outer heat collection tube.

6. The improved thermal graded vacuum tube according to claim 1, wherein, The heat collection tubes are provided in three parts, and all of them are fixedly connected to the transparent shell. The three heat collection tubes are arranged in parallel and at intervals.

7. An improved thermal tube vacuum collector according to claim 6, characterized in that, The number of the inner heat collection tube and the outer heat collection tube are both three, and one inner heat collection tube is fixedly connected inside each outer heat collection tube.

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