Heat exchange tubes and heat exchangers

Abstract

The present invention provides a heat exchange tube and a heat exchanger. The heat exchange tube includes: a first panel and a second panel disposed opposite to each other; and an outer baffle and an inner baffle disposed between the first panel and the second panel. The inner baffle is used to enclose a heat exchange flow path with the first panel and the second panel on the side opposite to the outer baffle. The outer baffle is disposed outside the inner baffle and is used to enclose a heat insulation channel with the inner baffle, the first panel and the second panel to block heat transfer from the outer baffle to the inner baffle. According to the heat exchange tube and the heat exchanger of the present invention, by providing a heat insulation channel between the outer baffle and the inner baffle to block heat transfer from the outer baffle to the inner baffle, deformation or damage of the internal components of the heat exchange tube caused by high temperature or temperature change is prevented, thereby improving the temperature resistance of the heat exchange tube, extending the service life, reducing the failure rate and improving the heat exchange efficiency.

Description

Technical Field

[0001] The present invention relates to a heat exchange device in the technical field of heat transfer, and more particularly to a heat exchange tube with improved temperature resistance and a heat exchanger including the heat exchange tube. Background Art

[0002] Glass tubes have excellent corrosion resistance. In particular, circular glass tubes are used as heat exchange tubes of heat exchange devices due to their mature manufacturing process and low cost. However, circular glass tubes have the defects of low heat exchange efficiency and insufficient structural compactness. Flat glass tubes can overcome the drawbacks of circular glass tubes. However, due to the limitation of the drawing process, the qualified rate is extremely low when the aspect ratio of the cross-section is large. And based on the characteristics of glass, the greater the aspect ratio, the more serious the stress concentration of the drawn flat glass tube, and the higher the failure rate when used as a heat exchange tube.

[0003] The plate-and-tube heat exchanger that has emerged in recent years has the advantages of high heat exchange efficiency, compact structure, convenient maintenance, and low leakage rate of heat exchange media. However, the components inside the heat exchange tube may be deformed or damaged when working in a high-temperature environment or when the working temperature changes, resulting in the failure of the heat exchange tube, the leakage of heat exchange media, the reduction of heat exchange efficiency, and the reduction of energy recovery rate. Summary of the Invention

[0004] The object of the present invention is to at least partially overcome the deficiencies mentioned above by providing a heat exchange tube and a heat exchanger.

[0005] According to one aspect of the present invention, there is provided a heat exchange tube, comprising: a first panel and a second panel disposed opposite to each other; and an outer baffle and an inner baffle disposed between the first panel and the second panel, wherein the inner baffle is used to enclose a heat exchange flow path with the first panel and the second panel on the side opposite to the outer baffle, and the outer baffle is disposed outside the inner baffle and is used to enclose a heat insulation channel with the inner baffle and the first panel and the second panel to block heat transfer from the outer baffle to the inner baffle.

[0006] In an exemplary embodiment, the ratio of the width of the heat insulation channel to the width of the heat exchange flow path is less than or equal to 1:10, preferably 1:30 to 1:20.

[0007] In an exemplary embodiment, the width of the heat insulation channel is less than or equal to 10 mm, preferably less than or equal to 8 mm, more preferably less than or equal to 5 mm.

[0008] In an exemplary embodiment, the width of the heat insulation channel is greater than or equal to 1 mm, preferably greater than or equal to 2 mm, more preferably greater than or equal to 3 mm to allow the heat exchange medium to flow through the heat insulation channel.

[0009] In an exemplary embodiment, the outer baffle and the inner baffle are separated from at least one of the first panel and the second panel and are connected together by an adhesive.

[0010] In an exemplary embodiment, the width of the outer baffle is smaller than the width of the inner baffle.

[0011] In an exemplary embodiment, the ratio of the sum of the widths of the outer baffle, the inner baffle and the heat insulation channel to the widths of the first panel and the second panel is less than or equal to 1:5, preferably less than or equal to 1:10.

[0012] In an exemplary embodiment, the outer baffle and the inner baffle are disposed on a first side of the first panel and the second panel, and the heat exchange tube further includes a single opposite baffle disposed on a second side opposite to the first side for enclosing a heat exchange flow channel with the first panel and the second panel.

[0013] In an exemplary embodiment, the inner baffle includes a first inner baffle and a second inner baffle, and the outer baffle includes a first outer baffle and a second outer baffle. The first inner baffle is disposed between the first outer baffle and the second inner baffle, and the second inner baffle is disposed between the first inner baffle and the second outer baffle. The first outer baffle, the first inner baffle, the first panel and the second panel enclose a first heat insulation channel, and the second outer baffle, the second inner baffle, the first panel and the second panel enclose a second heat insulation channel.

[0014] In an exemplary embodiment, the width of the first heat insulation channel is greater than the width of the second heat insulation channel.

[0015] In an exemplary embodiment, the first panel, the second panel, the first inner baffle, the second inner baffle, the first outer baffle and the second outer baffle are all independent components, and both the first panel and the second panel are hermetically connected to the first inner baffle, the second inner baffle, the first outer baffle and the second outer baffle by an adhesive.

[0016] In an exemplary embodiment, the heat exchange tube is a gas-gas heat exchange tube.

[0017] According to another aspect of the present invention, there is provided a heat exchanger, including: a housing including two oppositely disposed mounting plates, multiple first through holes being respectively formed on the mounting plates, and second through holes being formed on two oppositely disposed side surfaces of the housing perpendicular to the mounting plates; and a plurality of heat exchange tubes, two ends of each heat exchange tube being respectively hermetically connected to corresponding first through holes of the mounting plates, wherein at least one of the plurality of heat exchange tubes is any one of the heat exchange tubes described above.

[0018] In an exemplary embodiment, the heat exchanger further includes: a first seal and a second seal, which are disposed opposite to each other on both sides of each heat exchange tube, wherein an external shape formed by the first panel, the second panel, the first seal and the second seal is consistent with the shape of a first through hole of the mounting plate.

[0019] In an exemplary embodiment, the first seal and the second seal extend along an extension direction of a heat exchange flow path of the heat exchange tube, and a dimension in the extension direction is greater than a thickness of each mounting plate.

[0020] In an exemplary embodiment, the first seal and the second seal include an abutting portion and a side blocking portion, the abutting portion includes two abutting surfaces parallel to each other for abutting against the first panel and the second panel, and the side blocking portion extends perpendicular to an abutting surface of the abutting portion, so that the first seal and the second seal have a T-shaped cross-sectional shape.

[0021] In an exemplary embodiment, the first seal and the second seal are respectively and sealingly connected to the first panel and the second panel by an adhesive, and the first seal and the second seal are made of aluminum metal.

[0022] In an exemplary embodiment, the heat exchanger is an air preheater.

[0023] By means of the above technical solutions of the present invention, at least the following beneficial technical effects can be achieved:

[0024] According to the heat exchange tube and the heat exchanger of the present invention, by providing a heat insulation channel between the outer baffle and the inner baffle to block heat transfer from the outer baffle to the inner baffle, deformation or damage of internal components of the heat exchange tube caused by high temperature or temperature change is prevented, thereby improving the temperature resistance of the heat exchange tube, extending the service life, reducing the failure rate and improving the heat exchange efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] By reading the detailed description of the non-limiting embodiments with reference to the following drawings, other features, objects and advantages of the present invention will become more apparent:

[0026] Figure 1 is a cross-sectional view of a first embodiment of a heat exchange tube according to the present invention;

[0027] Figure 2 is a cross-sectional view of a second embodiment of a heat exchange tube according to the present invention;

[0028] Figure 3a is a cross-sectional view of a third embodiment of a heat exchange tube according to the present invention;

[0029] Figure 3bIs a perspective view of a third embodiment of a heat exchange tube according to the present invention;

[0030] Figure 3c Is a top view of a third embodiment of a heat exchange tube according to the present invention;

[0031] Figure 4 Is a cross-sectional view of a fourth embodiment of a heat exchange tube according to the present invention; and

[0032] Figure 5 Is a schematic structural view of a heat exchanger including a heat exchange tube according to the present invention. Detailed Description of the Invention

[0033] The present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It can be understood that the specific embodiments described herein are only for explaining the related invention and not for limiting the invention. Additionally, it should be noted that for the sake of description, only the parts related to the invention are shown in the drawings.

[0034] In the present invention, the orientation or positional relationship indicated by terms such as "upper", "lower", "inner", "outer", "center", "longitudinal", "transverse", etc. is based on the orientation or positional relationship shown in the drawings. These terms are mainly used to better describe the present invention and its embodiments, and are not used to limit that the indicated device, component, or component part must have a specific orientation or be constructed and operated in a specific orientation.

[0035] Figure 1 Is a cross-sectional view of a first embodiment of a heat exchange tube according to the present invention.

[0036] Refer to Figure 1 , in the first embodiment of the heat exchange tube of the present invention, the heat exchange tube 10 includes a first panel 111 and a second panel 112 disposed opposite to each other; and an outer baffle 120 and an inner baffle 130 disposed between the first panel 111 and the second panel 112. The inner baffle 130 is used to enclose with the first panel 111 and the second panel 112 on the side opposite to the outer baffle 120 to form a heat exchange flow path 140 for a heat exchange medium such as low-temperature air to flow. The outer baffle 120 is disposed outside the inner baffle 130 and is used to enclose with the inner baffle 130 and the first panel 111 and the second panel 112 to form a heat insulation channel 150 to block heat transfer from the outer baffle 120 to the inner baffle 130.

[0037] As Figure 1 shown, the heat exchange tube 10 may include two panels. For example, Figure 1The first panel 111 and the second panel 112 shown in []. It should be noted that the number of panels in the heat exchange tube 10 is not limited to two. For example, one of the first panel 111 and the second panel 112 can be formed by splicing two or more smaller panels.

[0038] In some embodiments, one of the first panel 111 and the second panel 112 can have a cross-sectional shape of L-shaped or U-shaped with different arm lengths, and the other has a flat plate shape, and the two are spliced to form a U-shaped cross-sectional shape with equal arm lengths. In other embodiments, the heat exchange tube 10 can include a single panel bent into a U-shape. In these embodiments, the outer baffle 120 and the inner baffle 130 are arranged on the open side of the U-shaped cross-section. The inner baffle 130 and the first panel 111 and the second panel 112 (or a single panel) can enclose a heat exchange flow channel 140, and the outer baffle 120 and the inner baffle 130 and the first panel 111 and the second panel 112 (or a single panel) can enclose a heat insulation channel 150.

[0039] Reference Figure 1 As shown, the outer baffle 120 and the inner baffle 130 are arranged on the first side of the first panel 111 and the second panel 112 (for example Figure 1 the right side in []), and the heat exchange tube 10 further includes a single opposite baffle 120'. The opposite baffle 120' is arranged on the second side opposite to the first side (for example Figure 1 the left side in []), and is used to enclose a heat exchange flow channel 140 with the first panel 111 and the second panel 112.

[0040] As Figure 1 shown, the inner baffle 130, the opposite baffle 120', the first panel 111 and the second panel 112 can enclose a heat exchange flow channel 140, and the outer baffle 120, the inner baffle 130, the first panel 111 and the second panel 112 can enclose a heat insulation channel 150. In this case, the heat exchange tube 10 only includes a heat exchange flow channel 140 and a heat insulation channel 150.

[0041] As Figure 1 shown, the first panel 111 and the second panel 112 can be arranged opposite to each other. For example, the first panel 111 and the second panel 112 can be arranged parallel to each other, but other arrangement methods are also feasible as long as the two panels are separated from each other by a certain distance.

[0042] In an embodiment of the present invention, at least one of the first panel 111 and the second panel 112 may be made of at least one of non-metallic materials such as glass, ceramic, graphite, silicon carbide, etc. Non-metallic materials such as glass, ceramic, graphite, silicon carbide, etc. have good heat conduction performance and corrosion resistance. In some examples, both the first panel 111 and the second panel 112 may be made of any one of glass, ceramic, graphite, silicon carbide. In other examples, one of the first panel 111 and the second panel 112 may be made of any one of glass, ceramic, graphite, silicon carbide (such as glass), and the other may be made of another one of these materials (such as ceramic), as long as the heat transfer requirements can be met.

[0043] In an embodiment of the present invention, the first panel 111 and the second panel 112 may have a rectangular shape, but other shapes are also feasible, such as other parallelogram shapes or trapezoidal shapes, etc. The first panel 111 and the second panel 112 may have the same shape and / or size. Of course, they may also have different shapes and / or sizes.

[0044] In an embodiment, at least one of the outer baffle 120 and the inner baffle 130 may be made of at least one of glass, ceramic, graphite, silicon carbide, for example. In some examples, both the outer baffle 120 and the inner baffle 130 may be made of any one of glass, ceramic, graphite, silicon carbide. In other examples, one of the outer baffle 120 and the inner baffle 130 may be made of any one of glass, ceramic, graphite, silicon carbide (such as glass), and the other may be made of another one of these materials (such as ceramic), as long as the heat transfer requirements can be met.

[0045] In an embodiment of the present invention, the heat insulation channel 150 may be provided between the outer baffle 120 and the inner baffle 130. When the heat exchange tube 10 is working, a heat exchange medium such as low-temperature air flows in the heat exchange flow channel 140 of the heat exchange tube 10, and at the same time exchanges heat with a heat exchange medium such as high-temperature flue gas outside the heat exchange tube 10. The heat insulation channel 150 can effectively reduce or block the heat transfer from the outer baffle 120 to the inner baffle 130 caused by a heat exchange medium such as high-temperature flue gas. Therefore, according to the embodiment of the present invention, the internal components of the heat exchange tube can be prevented from being deformed or damaged due to high temperature or temperature change, thereby improving the temperature resistance of the heat exchange tube, extending the service life, reducing the failure rate and improving the heat exchange efficiency.

[0046] In the context of the present invention, the width may be defined as the lateral dimension in a cross-section perpendicular to the extension direction of the heat exchange flow channel, the height may be defined as the vertical dimension in a cross-section perpendicular to the extension direction of the heat exchange flow channel, and the thickness may be defined as the dimension in the extension direction of the heat exchange flow channel. For example, in combinationFigure 1 As shown, width may refer to the dimension along the Y direction, height may refer to the dimension along the Z direction, and thickness may refer to the dimension along the X direction.

[0047] In a normal heat exchange flow channel design, it is expected that the flow area of each heat exchange flow channel is basically equal, the flow rate is uniform, and the heat exchange medium flows smoothly and the flow rate is uniform. However, in an embodiment of the present invention, the heat insulation channel is used to block the heat transfer from the outer baffle to the inner baffle, so there is no need to set the size of the heat insulation channel (such as the width) to be equal to the size of the heat exchange flow channel or equivalent to it. From the perspective of the overall heat exchange efficiency of the heat exchange tube, the heat insulation channel is set to have a size as small as possible so as not to affect the size of the heat exchange flow channel so that the heat exchange medium in the heat exchange flow channel does not flow smoothly and reduce the heat exchange efficiency. Therefore, in an embodiment of the present invention, the width of the heat insulation channel is intentionally set to be significantly smaller than the width of the heat exchange flow channel.

[0048] The heat transfer medium (e.g., low-temperature air) in the heat-insulating channel itself has a very low thermal conductivity. For example, the thermal conductivity of air at room temperature (20°C) is only 0.027W / (m·K), which is much lower than the thermal conductivity of glass of 0.7-1.3W / (m·K). In other words, the heat transfer medium in the heat-insulating channel itself is a very good heat-insulating material. Even when the flow rate of the heat transfer medium in the heat-insulating channel is very low or even does not flow, it can effectively prevent the heat obtained by the outer baffle from the heat transfer medium (e.g., high-temperature flue gas) outside the heat exchange tube from transferring inward, thereby better protecting the inner baffle.

[0049] Specifically, in the embodiment of the present invention, the flow area of the heat insulation channel 150 of the heat exchange tube 10 can be much smaller than the flow area of the heat exchange flow channel 140. For example, when the first panel 111 and the second panel 112 are Figure 1 When the heat insulation channel 150 and the heat exchange channel 140 are arranged parallel to each other, the ratio of the width of the heat insulation channel 150 to the width of the heat exchange channel 140 can be less than or equal to 1:10, preferably 1:30 to 1:20. In an embodiment of the present invention, the width of the heat insulation channel 150 can be less than or equal to 10 mm, preferably less than or equal to 8 mm, and more preferably less than or equal to 5 mm. With this arrangement, the flow rate of the heat exchange medium such as low-temperature air in the heat insulation channel 150 is significantly lower than the flow rate in the heat exchange channel 140.

[0050] For example, combined with Figure 1As shown, in one example, the spacing between the first panel 111 and the second panel 112 is 15 mm, the widths of the first panel 111 and the second panel 112 are 400 mm, the width of the inner baffle 130 is 20 mm, the width of the outer baffle 120 is 15 mm, the width of the opposite baffle 120' is 20 mm, the heights of the outer baffle 120, the inner baffle 130 and the opposite baffle 120' are all 15 mm, the width of the heat insulation channel 150 is only 3 - 5 mm, and the width of the heat exchange flow channel 140 is 340 - 342 mm. According to the flow velocity calculation formula of fluid mechanics and assuming that the hydraulic gradients and pipe wall roughnesses of the heat exchange flow channel 140 and the heat insulation channel 150 are the same, when the width of the heat insulation channel 150 is 3 mm and the width of the heat exchange flow channel 140 is 342 mm, the flow velocity of the heat exchange medium in the heat insulation channel 150 is about 31% of the flow velocity of the heat exchange medium in the heat exchange flow channel 140; when the width of the heat insulation channel 150 is 5 mm and the width of the heat exchange flow channel 140 is 345 mm, the flow velocity of the heat exchange medium in the heat insulation channel 150 is about 40% of the flow velocity of the heat exchange medium in the heat exchange flow channel 140. That is to say, the flow velocity of the heat exchange medium in the heat insulation channel 150 is only about 31% - 40% of the flow velocity in the heat exchange flow channel 140.

[0051] In an embodiment of the present invention, the width of the heat insulation channel 150 can be greater than or equal to 1 mm, preferably greater than or equal to 2 mm, more preferably greater than or equal to 3 mm, to allow the heat exchange medium to flow in the heat insulation channel 150. When the heat exchange medium (such as low-temperature air) flows in the heat insulation channel, the inner baffle and the outer baffle can be cooled by the way of flow heat exchange, which can effectively protect the inner baffle.

[0052] In an embodiment of the present invention, the outer baffle 120 and the inner baffle 130 can be separated from at least one of the first panel 111 and the second panel 112 and are connected together by an adhesive 160. In one example, the outer baffle 120 can be separated from the first panel 111 and the second panel 112 and is connected together by an adhesive 160; and the inner baffle 130 can be separated from the first panel 111 and the second panel 112 and is connected together by an adhesive 160.

[0053] The outer baffle and the inner baffle are connected to at least one of the first panel and the second panel by an adhesive, which can avoid the serious problem of stress concentration caused by the integral forming of traditional heat exchange tubes through processes such as drawing. The elastic property of the adhesive makes the heat exchange tube made by bonding it resistant to impact and strong in seismic resistance, further alleviating stress concentration. Moreover, due to the use of the bonding method for forming, complex processes such as melting, drawing, shaping, cutting, and grinding when manufacturing traditional glass tubes are avoided. The inventor found in practice that due to the relatively low refractory temperature of the adhesive, when the heat exchange medium outside the heat exchange tube (such as high-temperature flue gas) exceeds the temperature, the adhesive may oxidize and fall off, unable to ensure the overall sealing of the flat glass tube, causing the heat exchange medium inside the heat exchange tube (such as low-temperature air) to leak to the outside of the heat exchange tube, and then mixing with the heat exchange medium outside the heat exchange tube (such as high-temperature flue gas, usually under negative pressure). This not only causes a decrease in heat exchange efficiency but also increases the oxygen content of the heat exchange medium outside the heat exchange tube (such as high-temperature flue gas).

[0054] In an embodiment of the present invention, a hollow heat insulation channel is provided between the outer baffle and the inner baffle. The heat insulation channel cools the adhesive between the outer baffle and the first panel and the second panel, avoiding burning out when the temperature exceeds the limit. When it burns out, the adhesive between the outer baffle and the first panel and the second panel will burn out, and only the heat exchange medium (such as low-temperature air) in the heat insulation channel will leak into the flue gas environment outside the heat exchange tube.

[0055] In an embodiment of the present invention, as described above, the heat insulation channel has a relatively small width. Due to the small size, low flow rate, and small air volume of the heat insulation channel, the leakage amount is ensured to be small.

[0056] According to an embodiment of the present invention, due to the provision of the inner baffle, the adhesive between the inner baffle and the first panel and the second panel can prevent the gap between the first panel and the second panel and the outer baffle from being too large, further reducing the leakage amount. On the contrary, if there is no inner baffle, after the adhesive burns out, the gap between the first panel and the second panel and the outer baffle will become larger and larger, resulting in too large a leakage amount and causing the heat exchange tube to fail. Through the above configuration, even when the leakage amount of a single heat exchange tube is relatively large, the single heat exchange tube can be individually plugged or replaced without replacing the entire heat exchanger, which is beneficial to the maintenance of the heat exchange tube and reduces the maintenance cost.

[0057] In an embodiment of the present invention, the width of the outer baffle 120 may be smaller than the width of the inner baffle 130. As described above, the inner baffle 130 is used to define the heat exchange flow channel 140 with the first panel 111 and the second panel 112. In contrast, in the heat exchange tube 10, the outer baffle 120 is located outside the inner baffle 130 and is closer to or exposed to the heat exchange medium (such as high-temperature flue gas) outside the heat exchange tube 10 than the inner baffle 130. The outer baffle 120 acts as a buffer baffle or a sacrificial baffle. Burnout and leakage caused by overheating generally occur between the outer baffle 120 and the first panel 111 and the second panel 112. Therefore, the width of the outer baffle 120 can be set to be smaller than the width of the inner baffle 130.

[0058] In an embodiment of the present invention, the ratio of the sum of the widths of the outer baffle 120, the inner baffle 130, and the heat insulation channel 150 to the widths of the first panel 111 and the second panel 112 may be less than or equal to 1:5, and preferably may be less than or equal to 1:10. The outer baffle 120, the inner baffle 130, and the heat insulation channel 150 can be regarded as a baffle as a whole. By setting the widths of the three in the above manner, a large heat exchange area can be ensured without leakage of the heat exchange medium.

[0059] The following combines Figure 2 , Figure 3a , Figure 3b , Figure 3c and Figure 4 to describe other embodiments of the heat exchange tube according to the present invention. It should be noted that the description of the heat exchange tube 10 in the first embodiment in combination with Figure 1 also applies to the heat exchange tubes in the following embodiments.

[0060] Figure 2 is a cross-sectional view of a second embodiment of the heat exchange tube according to the present invention. The difference from Figure 1 in the first embodiment is that in Figure 2 in the second embodiment, the inner baffle of the heat exchange tube 20 may include a first inner baffle 131 and a second inner baffle 132, and the outer baffle of the heat exchange tube 20 may include a first outer baffle 121 and a second outer baffle 122.

[0061] As Figure 2As shown in the figure, the heat exchange tube 20 includes a first outer baffle 121 and a first inner baffle 131 disposed on the first side of the first panel 111 and the second panel 112, and a second outer baffle 122 and a second inner baffle 132 disposed on the second side opposite to the first side. Specifically, the first inner baffle 131 can be disposed between the first outer baffle 121 and the second inner baffle 132, and the second inner baffle 132 can be disposed between the first inner baffle 131 and the second outer baffle 122. The first inner baffle 131, the second inner baffle 132, the first panel 111, and the second panel 112 enclose to form a heat exchange flow channel 140. The first outer baffle 121, the first inner baffle 131, the first panel 111, and the second panel 112 can enclose to form a first heat insulation channel 151. The second outer baffle 122, the second inner baffle 132, the first panel 111, and the second panel 112 can enclose to form a second heat insulation channel 152.

[0062] In this embodiment, the first panel 111, the second panel 112, the first inner baffle 131, the second inner baffle 132, the first outer baffle 121, and the second outer baffle 122 can all be independent components, and the first panel 111 and the second panel 112 can all be hermetically connected to the first inner baffle 131, the second inner baffle 132, the first outer baffle 121, and the second outer baffle 122 through an adhesive 160.

[0063] In this embodiment, the width of the first heat insulation channel 151 can be greater than the width of the second heat insulation channel 152. In a gas-gas heat exchange tube, the flow directions of the heat exchange medium inside the heat exchange tube and the heat exchange medium outside the heat exchange tube can be orthogonal to each other to improve the heat exchange efficiency. In this embodiment, when the overall flow direction of the heat exchange medium (such as high-temperature flue gas) outside the heat exchange tube 20 is from the direction of the first outer baffle 121 to the direction of the second outer baffle 122 (for example, opposite to the Y direction in Figure 2 ), the first heat insulation channel 151 is located on the flue gas-facing side of the heat exchange tube 20, while the second heat insulation channel 152 is located on the flue gas-opposite side of the heat exchange tube 20. The first heat insulation channel 151 on the flue gas-facing side has a greater width than the second heat insulation channel 152 on the flue gas-opposite side, thereby providing a stronger cooling effect for the adhesive 160 between the first outer baffle 121 and the first panel 111 and the second panel 112, and avoiding the adhesive 160 of the first outer baffle 121 on the flue gas-facing side from being burned out at over-temperature.

[0064] Figure 3a is a cross-sectional view of a third embodiment of the heat exchange tube according to the present invention, Figure 3b is a perspective view of a third embodiment of the heat exchange tube according to the present invention, and Figure 3c is a top view of a third embodiment of the heat exchange tube according to the present invention.

[0065] Different from the second embodiment of Figure 2 is that in the third embodiment of Figure 3a , Figure 3b and Figure 3c , the heat exchange tube 30 further includes an intermediate baffle 170. For example, N intermediate baffles 170 can be arranged in the internal pipe of the heat exchange tube 30 to divide the internal pipe of the heat exchange tube 30 into N + 1 independent and sealed heat exchange channels 140 with each other, where N is an integer greater than or equal to 1. For example, as shown in Figure 3a , Figure 3b and Figure 3c , at least one intermediate baffle 170 can be arranged at the middle position in the width direction (Y direction) of the cross-section of the internal pipe of the heat exchange tube 30. The intermediate baffle 170 can be, for example, in a strip shape. The intermediate baffle 170 can, for example, extend through the heat exchange tube 30 along the extending direction of the heat exchange channels of the heat exchange tube 30. The intermediate baffle 170 can be, for example, arranged parallel to the first outer baffle 121, the second outer baffle 122, the first inner baffle 131 and the second inner baffle 132.

[0066] In the embodiments of the present invention, the intermediate baffle 170 can be hermetically connected to at least one of the first panel 111 and the second panel 112 through an adhesive 160. For example, the intermediate baffle 170 can be hermetically connected to both the first panel 111 and the second panel 112 through the adhesive 160.

[0067] For example, in combination with Figure 3a , Figure 3b and Figure 3c shown, in one example, the distance between the first panel 111 and the second panel 112 is 10 mm, the width of the first panel 111 and the second panel 112 is 400 mm, the widths of the first inner baffle 131, the second inner baffle 132 and the intermediate baffle 170 are all 20 mm, the widths of the first outer baffle 121 and the second outer baffle 122 are both 15 mm, the heights of the first outer baffle 121, the second outer baffle 122, the first inner baffle 131, the second inner baffle 132 and the intermediate baffle 170 are all 10 mm, the widths of the two heat exchange channels 140 are 150 mm, while the widths of the first heat insulation channel 151 and the second heat insulation channel 152 are only 5 mm. According to the flow velocity calculation formula of fluid mechanics and assuming that the hydraulic gradients and pipe wall roughnesses of the heat exchange channels 140 and the first heat insulation channel 151 and the second heat insulation channel 152 are the same, the flow velocity of the heat exchange medium (such as low-temperature air) in the first heat insulation channel 151 and the second heat insulation channel 152 is only about 50% of the flow velocity in the heat exchange channels 140.

[0068] In this embodiment, as shown in Figure 3a , Figure 3b and Figure 3cAs shown, the heat exchange tube 30 may optionally be further provided with a first seal 181 and a second seal 182. The first seal 181 and the second seal 182 may be disposed opposite to each other on the lateral sides of the heat exchange tube 30, for example, on both sides of the heat exchange tube 30 along the Y direction. As Figure 3b shown, the first seal 181 and the second seal 182 extend along the extending direction of the heat exchange flow path 140 of the heat exchange tube 30, for example, along the X direction.

[0069] In this embodiment, the first seal 181 and the second seal 182 may include an abutting portion and a side blocking portion. The abutting portion includes two parallel abutting surfaces for abutting against the first panel 111 and the second panel 112. The side blocking portion extends perpendicular to the abutting surface of the abutting portion, so that the first seal 181 and the second seal 182 have a T-shaped cross-sectional shape.

[0070] In this embodiment, the first seal 181 and the second seal 182 may be hermetically connected to the first panel 111 and the second panel 112 respectively through an adhesive 160, and the first seal 181 and the second seal 182 may be made of aluminum metal. The first seal 181 and the second seal 182 made of aluminum metal are easy to process and manufacture.

[0071] Although the first seal 181 and the second seal 182 are described as internal components of the heat exchange tube 30 in this embodiment, it should be understood that the first seal 181 and the second seal 182 may also be components independent of the heat exchange tube 30. When the heat exchange tube 30 is used for assembling a heat exchanger, the mounting plate for mounting the heat exchange tube 30 usually has a through hole that allows the heat exchange tube 30 to pass through and fixes one end of the heat exchange tube 30. The outer shape formed by the first panel 111, the second panel 112, the first seal 181 and the second seal 182 is consistent with the shape of the through hole of the mounting plate, so as to seal the through hole. This will be described in the embodiment of the heat exchanger described below.

[0072] Figure 4 is a cross-sectional view of a fourth embodiment of the heat exchange tube according to the present invention.

[0073] Different from Figure 3a 、 Figure 3b and Figure 3c the third embodiment of, in Figure 4In the fourth embodiment, the heat exchange tube 40 further includes at least one reinforcing rib 190. The reinforcing rib 190 can be disposed in the heat exchange flow path 140. In some examples, at least one of the reinforcing ribs 190 can be a strip structure, and the strip structure can extend, for example, along the extending direction of the heat exchange flow path 140 of the heat exchange tube 40 and can be disposed parallel to the outer baffle and / or the inner baffle. In some other examples, the strip structure can be arranged in an S shape or a Z shape within the heat exchange tube 40. In still some other examples, at least one of the reinforcing ribs 190 can also be a cylindrical structure, which is dispersedly arranged in the heat exchange flow path 140 of the heat exchange tube 40. For example, the cylindrical structure can support the first panel 111 and the second panel 112 of the heat exchange tube 40 in a column manner at multiple positions.

[0074] In an embodiment of the present invention, the reinforcing rib 190 can be connected to at least one of the first panel 111 and the second panel 112 through an adhesive 160. The reinforcing rib 190 has the effects of supporting the first panel 111 and the second panel 112, enhancing the disturbance of the heat exchange medium, and strengthening heat transfer. At the same time, it can also improve the strength of the heat exchange tube 40 and enhance the pressure-bearing capacity.

[0075] In the embodiments described above, the heat exchange tube according to the present invention is a gas-gas heat exchange tube, for example, a heat exchange tube used for heat exchange and energy recovery between low-temperature air and high-temperature flue gas. However, it should be understood that the heat exchange tube of the present invention is not limited thereto. The heat exchange medium inside the heat exchange tube is not limited to air, but can be any gas used for heat exchange, and the heat exchange medium outside the heat exchange tube is not limited to flue gas, but can be any gas used for heat exchange.

[0076] According to the embodiments of the present invention, the internal pipe of the heat exchange tube includes a heat exchange flow path and a heat insulation channel, which can improve the temperature resistance of the heat exchange tube while ensuring the corrosion resistance of the heat exchange tube.

[0077] According to the embodiments of the present invention, the width of the heat insulation channel of the heat exchange tube is much smaller than the width of the heat exchange flow path, which can ensure a larger heat exchange area. If the heat exchange medium leaks due to over-temperature, the leakage generally occurs between the outer baffle and the first panel and the second panel, that is, only the heat exchange medium flowing through the heat insulation channel leaks, so the leakage amount is small.

[0078] According to the embodiments of the present invention, when a large area of leakage occurs in the heat exchange tube, the leaking heat exchange tube can be individually blocked or replaced.

[0079] According to the embodiments of the present invention, the materials of the first seal and the second seal are aluminum metal, which is easy to process and manufacture.

[0080] The following combines Figure 5 to describe an embodiment of the heat exchanger according to the present invention.

[0081] Figure 5 is a schematic structural view of a heat exchanger including heat exchange tubes according to the present invention. As Figure 5 shown, according to an embodiment of the present invention, the heat exchanger 1 may include a housing 2 and a plurality of heat exchange tubes 3. The housing 2 may be generally box-shaped, for example. The housing 2 may include two mounting plates 4 disposed opposite to each other in the X direction. A plurality of first through holes (not shown) are respectively formed on each mounting plate 4. The housing 2 is formed with second through holes (not shown) on two opposite sides perpendicular to the mounting plates 4 (i.e., two sides of the housing 2 in the Y direction). Both ends of each heat exchange tube 3 are hermetically connected to the corresponding first through holes on the mounting plates 4, thereby providing a flow channel for a heat exchange medium such as low-temperature air. At least one of the plurality of heat exchange tubes 3 may be the heat exchange tubes 10, 20, 30, 40 described in the above embodiments.

[0082] As Figure 5 shown, a heat exchange medium such as low-temperature air may enter the heat exchange tube 3 from a mounting plate 4 on one side in the X direction (e.g., the left side in Figure 5 ). When the heat exchange medium such as low-temperature air flows through the heat exchange tube 3, it simultaneously exchanges heat with a heat exchange medium such as high-temperature flue gas outside the heat exchange tube 3, and then flows out from the mounting plate 4 on the other side (e.g., the right side in Figure 5 ). The heat exchange medium outside the heat exchange tube 3 (e.g., high-temperature flue gas) may enter the space between the heat exchange tube 3 and the housing 2 from a second through hole on one side of the housing 2 (e.g., the front side in Figure 5 ) in the -Y direction, exchange heat with the heat exchange medium (e.g., low-temperature air) in the heat exchange tube 3 when flowing through the space between the heat exchange tube 3 and the housing 2, and then flow out from the second through hole on the other side of the housing 2 (e.g., the rear side in Figure 5 ).

[0083] When the heat exchange tubes 3 are used for assembling to form the heat exchanger 1, the mounting plates 4 for mounting the heat exchange tubes 3 generally have through holes that allow the heat exchange tubes 3 to pass through and fix one end of the heat exchange tubes 3. In combination with Figure 3a , Figure 3b and Figure 3c as well as Figure 5 , the heat exchanger 1 may further include: a first seal 181 and a second seal 182, which are disposed opposite to each other on both sides of each heat exchange tube 3, wherein the outer shape formed by the first panel 111, the second panel 112, the first seal 181 and the second seal 182 is consistent with the shape of the first through hole of the mounting plate 4, thereby sealing the first through hole. The first seal 181 and the second seal 182 extend along the extension direction (e.g., the X direction) of the heat exchange flow path 140 of the heat exchange tube 3, and the dimension in the extension direction is greater than the thickness of each mounting plate 4, so that the first seal 181 and the second seal 182 seal the first through hole.

[0084] In an embodiment of the present invention, the first seal 181 and the second seal 182 include an abutting portion and a side blocking portion. The abutting portion includes two parallel abutting surfaces for abutting against the first panel 111 and the second panel 112. The side blocking portion extends perpendicular to the abutting surface of the abutting portion, so that the first seal 181 and the second seal 182 have a T-shaped cross-sectional shape.

[0085] In an embodiment of the present invention, the heat exchanger 1 is an air preheater.

[0086] The above description is only a preferred embodiment of the present invention and an explanation of the applied technical principles. Those skilled in the art should understand that the scope of the invention involved in the present invention is not limited to the technical solution formed by the specific combination of the above technical features, and should also cover other technical solutions formed by any combination of the above technical features or their equivalent features without departing from the inventive concept. For example, the technical solution formed by mutually replacing the above features with the (but not limited to) technical features having similar functions disclosed in the present invention.

Claims

1. A heat exchange tube, comprising: A first panel and a second panel disposed opposite to each other; And An outer baffle and an inner baffle disposed between the first panel and the second panel, Wherein, the inner baffle is used to enclose a heat exchange flow channel with the first panel and the second panel on a side opposite to the outer baffle, and the outer baffle is disposed outside the inner baffle and is used to enclose a heat insulation channel with the inner baffle and the first panel and the second panel to block heat transfer from the outer baffle to the inner baffle.

2. The heat exchange tube according to claim 1, wherein, The ratio of the width of the heat insulation channel to the width of the heat exchange flow channel is less than or equal to 1:

10.

3. The heat exchange tube according to claim 1, wherein, The ratio of the width of the heat insulation channel to the width of the heat exchange flow channel is 1:30 to 1:

20.

4. The heat exchange tube according to any one of claims 1-3, wherein, The width of the heat insulation channel is less than or equal to 10 mm.

5. The heat exchange tube according to any one of claims 1 to 3, wherein, The width of the heat insulation channel is less than or equal to 8 mm.

6. The heat exchange tube according to any one of claims 1-3, wherein, The width of the heat insulation channel is less than or equal to 5 mm.

7. The heat exchange tube according to claim 4, wherein, The width of the heat insulation channel is greater than or equal to 1 mm.

8. The heat exchange tube according to claim 4, wherein, The width of the heat insulation channel is greater than or equal to 2 mm to allow the heat exchange medium to flow in the heat insulation channel.

9. The heat exchange tube according to claim 4, wherein, The width of the heat insulation channel is greater than or equal to 3 mm to allow the heat exchange medium to flow in the heat insulation channel.

10. The heat exchange tube according to claim 1, wherein, The outer baffle and the inner baffle are separated from at least one of the first panel and the second panel and are connected together by an adhesive.

11. The heat exchange tube according to claim 1, wherein, The width of the outer baffle is less than the width of the inner baffle.

12. The heat exchange tube according to claim 1, wherein, The ratio of the sum of the widths of the outer baffle, the inner baffle and the heat insulation channel to the width of the first panel and the second panel is less than or equal to 1:

5.

13. The heat exchange tube according to claim 1, wherein, The ratio of the sum of the widths of the outer baffle, the inner baffle and the heat insulation channel to the width of the first panel and the second panel is less than or equal to 1:

10.

14. The heat exchange tube according to claim 1, wherein, The outer baffle and the inner baffle are disposed on a first side of the first panel and the second panel, and the heat exchange tube further includes a single opposite baffle disposed on a second side opposite to the first side for enclosing a heat exchange flow channel with the first panel and the second panel.

15. The heat exchange tube according to claim 1, wherein, The inner baffle includes a first inner baffle and a second inner baffle, and the outer baffle includes a first outer baffle and a second outer baffle, The first inner baffle is disposed between the first outer baffle and the second inner baffle, and the second inner baffle is disposed between the first inner baffle and the second outer baffle, The first outer baffle, the first inner baffle, the first panel and the second panel enclose a first heat insulation channel, and the second outer baffle, the second inner baffle, the first panel and the second panel enclose a second heat insulation channel.

16. The heat exchange tube according to claim 15, wherein, The width of the first heat insulation channel is greater than the width of the second heat insulation channel.

17. The heat exchange tube according to claim 15, wherein, The first panel, the second panel, the first inner baffle, the second inner baffle, the first outer baffle and the second outer baffle are all independent components, and the first panel and the second panel are hermetically connected to the first inner baffle, the second inner baffle, the first outer baffle and the second outer baffle by an adhesive.

18. The heat exchange tube according to claim 1, wherein, The heat exchange tube is a gas-gas heat exchange tube.

19. A heat exchanger, comprising: A housing, said housing including two oppositely arranged mounting plates, a plurality of first through holes being respectively formed in said mounting plates, and second through holes being formed in two oppositely arranged side surfaces of said housing that are perpendicular to said mounting plates; and A plurality of heat exchange tubes, two ends of each heat exchange tube being respectively and sealingly connected to corresponding first through holes of said mounting plates, wherein at least one of said plurality of heat exchange tubes is a heat exchange tube according to any one of claims 1-18.

20. The heat exchanger according to claim 19 further comprises: A first seal and a second seal, oppositely arranged on two sides of each heat exchange tube, wherein the outer shape formed by said first panel, second panel, first seal and second seal is consistent with the shape of the first through hole of said mounting plate.

21. The heat exchanger according to claim 20, wherein, Said first seal and second seal extend along the extending direction of the heat exchange flow path of said heat exchange tube, and the dimension in said extending direction is greater than the thickness of each mounting plate.

22. The heat exchanger according to claim 21, wherein, Said first seal and second seal include abutting portions and side blocking portions, said abutting portions including two mutually parallel abutting surfaces for abutting against said first panel and second panel, and said side blocking portions extending perpendicular to the abutting surfaces of said abutting portions, such that said first seal and second seal have a T-shaped cross-sectional shape.

23. The heat exchanger according to any one of claims 20-22, wherein, Said first seal and second seal are respectively and sealingly connected to said first panel and second panel by an adhesive, and said first seal and second seal are made of aluminum metal.

24. The heat exchanger according to claim 19, wherein said heat exchanger is an air preheater.

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