CN114234684A - Heat exchange tube and heat exchanger - Google Patents

Abstract

The 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 outside barrier and an inside barrier disposed between the first panel and the second panel. The inner baffle is used for enclosing the first panel and the second panel at the side opposite to the outer baffle to form a heat exchanging channel. The outer baffle is disposed outside the inner baffle and is configured to form an insulating channel with the inner baffle and the first and second panels to block heat transfer from the outer baffle to the inner baffle. According to the heat exchange tube and the heat exchanger, the heat insulation channel is arranged between the outer side baffle and the inner side baffle to obstruct heat transfer from the outer side baffle to the inner side baffle, and the deformation or damage of internal components of the heat exchange tube caused by high temperature or temperature change is prevented, so that the temperature resistance of the heat exchange tube is improved, the service life is prolonged, the failure rate is reduced, and the heat exchange efficiency is improved.

Description

Heat exchange tube and heat exchanger

Technical Field

The invention relates to a heat exchange device in the technical field of heat transfer, in particular to a heat exchange tube with improved temperature resistance and a heat exchanger comprising the heat exchange tube.

Background

The glass tube has excellent corrosion resistance, and particularly, the round glass tube is used as a heat exchange tube of a heat exchange device due to the advantages of mature manufacturing process and low cost. However, the circular glass tube has the defects of low heat exchange efficiency and insufficient structural compactness. The flat glass tube can overcome the disadvantages of the circular glass tube, but the yield is very low when the length and width of the cross section is large due to the drawing process limitation, and the larger the length and width ratio is, the more severe the stress concentration of the drawn flat glass tube is, and the higher the failure rate when used as a heat exchange tube is, based on the characteristics of glass.

The plate-tube heat exchanger which appears in recent years has the advantages of high heat exchange efficiency, compact structure, convenient maintenance, low leakage rate of heat exchange media and the like. However, components inside the heat exchange tube may be deformed or damaged in a high-temperature working environment or when the working temperature changes, which may cause failure of the heat exchange tube, leakage of a heat exchange medium, reduction of heat exchange efficiency, and reduction of energy recovery rate.

Disclosure of Invention

It is an object of the present invention to at least partially overcome the above-mentioned deficiencies by providing a heat exchange tube and a heat exchanger.

According to an aspect of the present invention, there is provided a heat exchange pipe 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 configured to enclose a heat exchanging passageway with the first panel and the second panel on a side opposite the outer baffle, and the outer baffle is disposed outside the inner baffle and configured to enclose an insulating passageway with the inner baffle and the first panel and the second panel to block heat transfer from the outer baffle to the inner baffle.

In an exemplary embodiment, 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, and preferably 1:30 to 1: 20.

In an exemplary embodiment, the width of the insulating channel is less than or equal to 10mm, preferably less than or equal to 8mm, more preferably less than or equal to 5 mm.

In an exemplary embodiment, the width of the insulating channel is greater than or equal to 1mm, preferably greater than or equal to 2mm, more preferably greater than or equal to 3mm, to allow the heat exchange medium to circulate within the insulating channel.

In an exemplary embodiment, the outer and inner fenders are separate from at least one of the first and second panels and are joined together by an adhesive.

In an exemplary embodiment, the width of the outboard flap is less than the width of the inboard flap.

In an exemplary embodiment, the ratio of the sum of the widths of the outer baffle, inner baffle and insulating channel to the widths of the first and second panels is less than or equal to 1:5, preferably less than or equal to 1: 10.

In an exemplary embodiment, the outboard and inboard baffles are disposed on a first side of the first and second panels, and the heat exchange tube further includes a single, opposite side baffle disposed on a second side opposite the first side for forming a heat exchange path about the first and second panels.

In an exemplary embodiment, the inboard flaps comprise first and second inboard flaps and the outboard flaps comprise first and second outboard flaps. The first inside baffle is disposed between the first outside baffle and the second inside baffle, and the second inside baffle is disposed between the first inside baffle and the second outside baffle. The first outer side baffle, the first inner side baffle, the first panel and the second panel surround to form a first heat insulation channel, and the second outer side baffle, the second inner side baffle, the first panel and the second panel surround to form a second heat insulation channel.

In an exemplary embodiment, a width of the first insulating channel is greater than a width of the second insulating channel.

In an exemplary embodiment, the first panel, the second panel, the first inside barrier, the second inside barrier, the first outside barrier and the second outside barrier are separate components, and the first panel and the second panel are each sealingly joined to the first inside barrier, the second inside barrier, the first outside barrier and the second outside barrier with an adhesive.

In an exemplary embodiment, the heat exchange tubes are gas-to-gas heat exchange tubes.

According to another aspect of the present invention, there is provided a heat exchanger comprising: the shell comprises two opposite mounting plates, a plurality of first through holes are formed in the mounting plates respectively, and second through holes are formed in two opposite side surfaces perpendicular to the mounting plates; and a plurality of heat exchange tubes, both ends of each heat exchange tube being hermetically connected to the corresponding first through holes of the mounting plate, respectively, wherein at least one of the plurality of heat exchange tubes is any one of the heat exchange tubes as described above.

In an exemplary embodiment, the heat exchanger further comprises: and a first sealing member and a second sealing member which are disposed opposite to each other at both sides of each heat exchange pipe, wherein the first panel, the second panel, the first sealing member and the second sealing member form an external shape in conformity with the shape of the first through-hole of the mounting plate.

In an exemplary embodiment, the first and second seals extend along an extending direction of the heat exchange flow channel of the heat exchange tube, and a dimension in the extending direction is greater than a thickness of each mounting plate.

In an exemplary embodiment, the first and second seals comprise an abutment portion comprising two abutment faces for abutment against the first and second panels parallel to each other and a skirt portion extending perpendicular to the abutment faces of the abutment portion, so that the first and second seals have a T-shaped cross-sectional shape.

In an exemplary embodiment, the first and second seals are sealingly joined to the first and second panels, respectively, by an adhesive, and the first and second seals are made of metallic aluminum.

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

By means of the technical scheme, at least the following beneficial technical effects can be realized:

according to the heat exchange tube and the heat exchanger, the heat insulation channel is arranged between the outer side baffle and the inner side baffle to obstruct heat transfer from the outer side baffle to the inner side baffle, and the deformation or damage of internal components of the heat exchange tube caused by high temperature or temperature change is prevented, so that the temperature resistance of the heat exchange tube is improved, the service life is prolonged, the failure rate is reduced, and the heat exchange efficiency is improved.

Drawings

Other features, objects and advantages of the invention will become more apparent upon reading of the detailed description of non-limiting embodiments made with reference to the following drawings:

FIG. 1 is a cross-sectional view of a first embodiment of a heat exchange tube according to the present invention;

FIG. 2 is a cross-sectional view of a second embodiment of a heat exchange tube according to the present invention;

FIG. 3a is a cross-sectional view of a third embodiment of a heat exchange tube according to the present invention;

FIG. 3b is a perspective view of a third embodiment of a heat exchange tube according to the present invention;

FIG. 3c is a top view of a third embodiment of a heat exchange tube according to the present invention;

FIG. 4 is a cross-sectional view of a fourth embodiment of a heat exchange tube according to the present invention; and is

Fig. 5 is a schematic view of a heat exchanger including a heat exchange tube according to the present invention.

Detailed Description

The present invention will be described in further detail with reference to the accompanying drawings and examples. It is to be understood that the specific embodiments described herein are merely illustrative of the relevant invention and not restrictive of the invention. It should be noted that, for convenience of description, only the portions related to the present invention are shown in the drawings.

In the present invention, the terms "upper", "lower", "inner", "outer", "center", "longitudinal", "lateral", and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings. These terms are used primarily to better describe the invention and its embodiments and are not intended to limit the indicated devices, components or elements to a particular orientation or to be constructed and operated in a particular orientation.

Fig. 1 is a cross-sectional view of a first embodiment of a heat exchange tube according to the present invention.

Referring to fig. 1, in a first embodiment of the heat exchange tube of the present invention, the heat exchange tube 10 comprises a first panel 111 and a second panel 112 disposed opposite to each other; and an outside barrier 120 and an inside barrier 130 disposed between the first panel 111 and the second panel 112. The inside barrier 130 is used to enclose the first and second panels 111 and 112 at a side opposite to the outside barrier 120 to form a heat exchange flow channel 140 for flowing a heat exchange medium such as low temperature air, for example. The outside barrier 120 is disposed outside the inside barrier 130 and serves to form an insulation passage 150 with the inside barrier 130 and the first and second panels 111 and 112 to block heat transfer from the outside barrier 120 to the inside barrier 130.

As shown in fig. 1, the heat exchange tube 10 may include two panels, for example, a first panel 111 and a second panel 112 shown in fig. 1. 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 may be formed by splicing two or more smaller panels.

In some embodiments, one of the first panel 111 and the second panel 112 may have an L-shape or a U-shape in cross section with two arms of different lengths, and the other has a flat plate shape, and the two panels are joined to form a U-shape in cross section with two arms of equal length. In other embodiments, the heat exchange tube 10 may comprise a single panel bent in a U-shape. In these embodiments, the outside barrier 120 and the inside barrier 130 are disposed at the open side of the U-shaped cross-section, the inside barrier 130 and the first panel 111 and the second panel 112 (or a single panel) may enclose a heat exchange flow channel 140, and the outside barrier 120 and the inside barrier 130 and the first panel 111 and the second panel 112 (or a single panel) may enclose an insulation channel 150.

Referring to fig. 1, the outside barrier 120 and the inside barrier 130 are disposed on a first side (e.g., the right side in fig. 1) of the first and second panels 111 and 112, and the heat exchange tube 10 further includes a single opposite-side barrier 120'. The opposite-side baffle 120' is disposed at a second side (e.g., the left side in fig. 1) opposite to the first side for enclosing the heat exchange flow channel 140 with the first and second panels 111 and 112.

As shown in fig. 1, the inside baffle 130, the opposite side baffle 120', the first panel 111 and the second panel 112 may enclose a heat exchange flow channel 140, and the outside baffle 120, the inside baffle 130, the first panel 111 and the second panel 112 may enclose an insulation channel 150. In this case, the heat exchange tube 10 includes only one heat exchange flow channel 140 and one insulation channel 150.

As shown in fig. 1, the first panel 111 and the second panel 112 may be disposed opposite to each other. For example, the first panel 111 and the second panel 112 may be arranged parallel to each other, but other arrangements are possible as long as the two panels are spaced apart from each other by a certain distance.

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, and the like. Non-metallic materials such as glass, ceramics, graphite, silicon carbide and the like have good heat-conducting property and corrosion resistance. In some examples, the first panel 111 and the second panel 112 may each be made of any one of glass, ceramic, graphite, and silicon carbide. In other examples, one of the first and second panels 111 and 112 may be made of any one of glass, ceramic, graphite, and silicon carbide (e.g., glass), and the other may be made of another one of these materials (e.g., ceramic), as long as the heat transfer requirements are met.

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 possible, 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, although they may have different shapes and/or sizes.

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, and silicon carbide, for example. In some examples, the outer baffle 120 and the inner baffle 130 may each be made of any one of glass, ceramic, graphite, and 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, and silicon carbide (e.g., glass), while the other may be made of another one of these materials (e.g., ceramic), as long as the heat transfer requirements are met.

In an embodiment of the present invention, the insulation passage 150 may be disposed between the outside barrier 120 and the inside barrier 130. When the heat exchange tube 10 is in operation, a heat exchange medium such as low temperature air flows in the heat exchange flow channel 140 of the heat exchange tube 10 while exchanging heat with a heat exchange medium such as high temperature flue gas outside the heat exchange tube 10. The insulating passageway 150 is effective to mitigate or block 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 invention, the deformation or damage of the internal components of the heat exchange tube caused by high temperature or temperature change can be prevented, thereby improving the temperature resistance of the heat exchange tube, prolonging the service life, reducing the failure rate and improving the heat exchange efficiency.

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 connection with fig. 1, width may refer to a dimension in the Y-direction, height may refer to a dimension in the Z-direction, and thickness may refer to a dimension in the X-direction.

In the normal heat exchange flow channel design, the flow areas of all the heat exchange flow channels are expected to be basically equal, the flow speeds are expected to be uniform, and the heat exchange medium flows smoothly and the flow is expected to be uniform. However, in the embodiment of the present invention, the insulation passage serves to block heat transfer from the outside baffle to the inside baffle, and thus it is not necessary to set the size (e.g., width) of the insulation passage to be equal to or comparable to the size of the heat exchange flow channel. Considering from the overall heat exchange efficiency of the heat exchange tube, the heat insulation channel is set to have the size as small as possible, so that the size of the heat exchange channel is not influenced, the heat exchange medium in the heat exchange channel can not smoothly flow, and the heat exchange efficiency is reduced. Thus, in embodiments of the invention, the width of the insulating channel is intentionally set to be significantly smaller than the width of the heat exchange flow channel.

The heat conductivity coefficient of a heat exchange medium (such as low-temperature air) in the heat insulation channel is very low, for example, the heat conductivity coefficient of the air at normal temperature (20 ℃) is only 0.027W/(m.K), which is far lower than that of glass by 0.7-1.3W/(m.K). That is, the heat exchange medium in the heat insulation channel is a good heat insulation material. Even under the condition that the flow velocity of the heat exchange medium in the heat insulation channel is low or even does not flow, the inward transfer of heat obtained by the outer baffle from the heat exchange medium (such as high-temperature flue gas) outside the heat exchange tube can be effectively blocked, so that the inner baffle is well protected.

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

For example, as shown in fig. 1, in one example, the distance between the first panel 111 and the second panel 112 is 15mm, the widths of the first panel 111 and the second panel 112 are 400mm, the width of the inner baffle 130 is 20mm, the width of the outer baffle 120 is 15mm, the width of the opposite baffle 120 'is 20mm, the heights of the outer baffle 120, the inner baffle 130 and the opposite baffle 120' are all 15mm, 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 a flow rate calculation formula of fluid mechanics and assuming that the hydraulic gradient and the pipe wall roughness 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 3mm and the width of the heat exchange flow channel 140 is 342mm, the flow rate of the heat exchange medium in the heat insulation channel 150 is about 31% of the flow rate of the heat exchange medium in the heat exchange flow channel 140; when the width of the heat insulation channel 150 is 5mm and the width of the heat exchange flow channel 140 is 345mm, the flow rate of the heat exchange medium in the heat insulation channel 150 is about 40% of the flow rate of the heat exchange medium in the heat exchange flow channel 140. That is, the flow rate of the heat exchange medium in the heat insulation passage 150 is only about 31% to 40% of the flow rate in the heat exchange flow channel 140.

In an embodiment of the present invention, the width of the insulation channel 150 may be greater than or equal to 1mm, preferably greater than or equal to 2mm, and more preferably greater than or equal to 3mm to allow the heat exchange medium to flow through the insulation channel 150. When a heat exchange medium (such as low-temperature air) circulates in the heat insulation channel, the inner baffle and the outer baffle are cooled in a flowing heat exchange mode, and the inner baffle can be effectively protected.

In an embodiment of the present invention, the outer and inner barriers 120 and 130 and at least one of the first and second panels 111 and 112 may be separate and joined together by an adhesive 160. In one example, the outer baffle 120 and the first and second panels 111, 112 may be separate, joined together by an adhesive 160; and the inner barrier 130 and the first and second panels 111 and 112 may be separate and joined together by an adhesive 160.

The outside barrier and the inside barrier are joined to at least one of the first panel and the second panel by an adhesive, which can avoid a problem of severe stress concentration caused by integral molding of the conventional heat exchange tube by drawing or the like. The elastic property of the binder enables the heat exchange tube made of the binder to be impact-resistant and strong in shock resistance, and further relieves stress concentration. In addition, because the bonding mode is adopted for forming, the complex processes of melting, drawing, shaping, cutting, grinding and the like which are carried out when the traditional glass tube is manufactured are avoided. The inventor finds in practice that due to the low fire-resistant temperature of the binder, when the heat exchange medium (such as high-temperature flue gas) outside the heat exchange tube is over-temperature, the binder may be oxidized and fall off, the integral sealing performance of the flat glass tube cannot be ensured, and the heat exchange medium (such as low-temperature air) inside the heat exchange tube leaks to the outside of the heat exchange tube and is further mixed with the heat exchange medium (such as high-temperature flue gas, usually under negative pressure) outside the heat exchange tube. This not only causes a decrease in heat exchange efficiency, but also increases the oxygen content of the heat exchange medium (e.g., high-temperature flue gas) outside the heat exchange tubes.

In an embodiment according to the invention, a hollow insulating channel is provided between the outer and inner baffles. The heat insulation channel is used for cooling the binder between the outer side baffle and the first panel and the second panel, and burning out of the binder in overtemperature is avoided. When burned out, the adhesive between the outside baffle and the first and second panels will burn out and only the heat exchange medium (e.g., low temperature air) in the insulating channel will leak into the flue gas environment outside the heat exchange tube.

In an embodiment according to the invention, the insulating channel has a smaller width, as described above. The size of the heat insulation channel is small, the flow speed is low, and the air volume is small, so that the leakage amount is ensured to be small.

According to the embodiment of the invention, due to the arrangement of the inner side baffle, the adhesive between the inner side baffle and the first panel and the second panel can avoid overlarge gaps between the first panel and the second panel and the outer side baffle, and the leakage amount is further reduced. On the contrary, if the inside baffle is not provided, after the binder is burnt out, the gaps between the first panel and the second panel and the outside baffle become larger and larger, so that the leakage amount is too large, and the heat exchange tube fails. Through the configuration, even if the leakage amount of a single heat exchange tube is large, the single heat exchange tube can be independently plugged or replaced without replacing the whole heat exchanger, so that the maintenance of the heat exchange tube is facilitated, and the maintenance cost is reduced.

In an embodiment of the present invention, the width of the outside barrier 120 may be smaller than the width of the inside barrier 130. As described above, the inside barrier 130 serves to define the heat exchange flow channel 140 with the first and second panels 111 and 112. In contrast, in the heat exchange tube 10, the outside baffle 120 is located outside the inside baffle 130, closer to or exposed to the heat exchange medium (e.g., high temperature flue gas) outside the heat exchange tube 10 than the inside baffle 130. The outboard baffle 120 acts as a buffer baffle or a sacrificial baffle. Burnout and leakage due to over-temperature generally occur between the outside barrier 120 and the first and second panels 111 and 112. Therefore, the width of the outside barrier 120 may be set smaller than the width of the inside barrier 130.

In an embodiment of the present invention, the ratio of the sum of the widths of the outside barrier 120, the inside barrier 130, and the 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 combination of the outboard baffle 120, the inboard baffle 130, and the insulating passageway 150 may be considered as a single baffle. By setting the widths of the three in the above manner, a larger heat exchange area can be ensured under the condition that the heat exchange medium does not leak.

Other embodiments of heat exchange tubes according to the present invention are described below in conjunction with fig. 2, 3a, 3b, 3c and 4. It should be noted that the above description of the heat exchange tube 10 of the first embodiment with reference to fig. 1 is equally applicable to the heat exchange tubes of the embodiments described below.

Fig. 2 is a cross-sectional view of a second embodiment of a heat exchange tube according to the present invention. The difference from the first embodiment of fig. 1 is that, in the second embodiment of fig. 2, the inside barrier of the heat exchange tube 20 may comprise a first inside barrier 131 and a second inside barrier 132, and the outside barrier of the heat exchange tube 20 may comprise a first outside barrier 121 and a second outside barrier 122.

As shown in fig. 2, the heat exchange tube 20 includes first outside baffles 121 and first inside baffles 131 disposed on first sides of the first and second panels 111 and 112, and second outside baffles 122 and second inside baffles 132 disposed on second sides opposite the first sides. Specifically, the first inside barrier 131 may be disposed between the first and second outside barriers 121 and 132, and the second inside barrier 132 may be disposed between the first and second outside barriers 131 and 122. The first inner baffle 131, the second inner baffle 132, the first panel 111 and the second panel 112 enclose a heat exchange flow channel 140. The first outboard baffle 121, the first inboard baffle 131, the first panel 111, and the second panel 112 may enclose a first insulated channel 151. The second outboard baffle 122, the second inboard baffle 132, the first panel 111, and the second panel 112 may enclose a second insulated channel 152.

In the present embodiment, the first panel 111, the second panel 112, the first inside barrier 131, the second inside barrier 132, the first outside barrier 121, and the second outside barrier 122 may each be a separate component, and the first panel 111 and the second panel 112 may each be hermetically connected to the first inside barrier 131, the second inside barrier 132, the first outside barrier 121, and the second outside barrier 122 by the adhesive 160.

In this embodiment, the width of the first insulating pathway 151 may be greater than the width of the second insulating pathway 152. In the 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 may be orthogonal to each other to improve heat exchange efficiency. In the present embodiment, when the overall flow direction of the heat exchange medium (e.g., high temperature flue gas) outside the heat exchange tubes 20 is a direction (e.g., opposite to the Y direction in fig. 2) directed from the first outside baffle 121 to the second outside baffle 122, the first heat insulation channels 151 are located on the flue gas facing side of the heat exchange tubes 20, and the second heat insulation channels 152 are located on the flue gas back side of the heat exchange tubes 20. The first heat insulation channel 151 on the smoke facing side has a larger width than the second heat insulation channel 152 on the smoke back side, so that a stronger cooling effect is provided for the adhesive 160 between the first outer side baffle 121 and the first and second panels 111 and 112, and the adhesive 160 of the first outer side baffle 121 on the smoke facing side is prevented from being burned out when the temperature is over-high.

Fig. 3a is a cross-sectional view, fig. 3b is a perspective view and fig. 3c is a plan view of a third embodiment of a heat exchange tube according to the present invention.

The difference from the second embodiment of fig. 2 is that, in the third embodiment of fig. 3a, 3b and 3c, the heat exchange tubes 30 further include intermediate baffles 170. For example, N intermediate baffles 170 may be disposed in the inner tube of the heat exchange tube 30 to divide the inner tube of the heat exchange tube 30 into N +1 independent heat exchange flow channels 140 sealed from each other, where N is an integer greater than or equal to 1. For example, as shown in fig. 3a, 3b and 3c, one intermediate baffle 170 may be provided at least at an intermediate position in the width direction (Y direction) of the cross section of the inner tube of the heat exchange tube 30. The intermediate baffle 170 may be, for example, in the shape of a bar. The intermediate baffle 170 may penetrate the heat exchange tube 30, for example, in the heat exchange flow channel extension direction of the heat exchange tube 30. The intermediate baffle 170 may be disposed, for example, in parallel with the first and second outside baffles 121 and 122 and the first and second inside baffles 131 and 132.

In an embodiment of the present invention, the intermediate baffle 170 may be sealingly joined with at least one of the first panel 111 and the second panel 112 by an adhesive 160. For example, the intermediate baffle 170 may be sealingly joined to both the first panel 111 and the second panel 112 by the adhesive 160.

For example, as shown in fig. 3a, 3b and 3c, in one example, the spacing between the first and second panels 111 and 112 is 10mm, the width of the first and second panels 111 and 112 is 400mm, the width of each of the first, second and middle baffles 131, 132 and 170 is 20mm, the width of each of the first and second outer baffles 121 and 122 is 15mm, the height of each of the first and second outer baffles 121, 122, 131, 132 and 170 is 10mm, the width of the two heat exchange flow channels 140 is 150mm, and the width of the first and second insulation channels 151 and 152 is only 5 mm. According to the flow rate calculation formula of fluid mechanics and assuming that the hydraulic gradient and the pipe wall roughness of the heat exchange flow channel 140 and the first and second heat insulation channels 151 and 152 are the same, the flow rate of the heat exchange medium (e.g., the low temperature air) in the first and second heat insulation channels 151 and 152 is only about 50% of the flow rate in the heat exchange flow channel 140.

In the present embodiment, as shown in fig. 3a, 3b and 3c, the heat exchange pipe 30 is optionally further provided with a first sealing member 181 and a second sealing member 182. The first and second sealing members 181 and 182 may be disposed opposite to each other at both lateral sides of the heat exchange pipe 30, for example, both sides of the heat exchange pipe 30 in the Y direction. As shown in fig. 3b, the first and second sealing members 181 and 182 extend along the extension direction of the heat exchange flow channel 140 of the heat exchange tube 30, for example, along the X direction.

In the present embodiment, the first and second seals 181 and 182 may include an abutting portion including two abutting surfaces for abutting the first and second panels 111 and 112 in parallel with each other, and a side blocking portion extending perpendicular to the abutting surfaces of the abutting portion, so that the first and second seals 181 and 182 have a T-shaped cross-sectional shape.

In the present embodiment, the first and second sealing members 181 and 182 may be sealingly coupled with the first and second panels 111 and 112, respectively, by the adhesive 160, and the first and second sealing members 181 and 182 may be made of metal aluminum. The first and second sealing members 181 and 182 made of metallic aluminum are easy to manufacture.

Although the first and second seals 181 and 182 are described as internal components of the heat exchange pipe 30 in the present embodiment, it is understood that the first and second seals 181 and 182 may be separate components from the heat exchange pipe 30. When the heat exchange pipe 30 is used for assembly to form a heat exchanger, a mounting plate for mounting the heat exchange pipe 30 generally has a through hole allowing the heat exchange pipe 30 to pass therethrough and fixing one end of the heat exchange pipe 30. The first panel 111, the second panel 112, the first seal 181, and the second seal 182 form an external shape conforming to the shape of the through-hole of the mounting plate, thereby sealing the through-hole. This will be described in the embodiments of the heat exchanger described below.

Fig. 4 is a cross-sectional view of a fourth embodiment of a heat exchange tube according to the present invention.

The difference from the third embodiment of fig. 3a, 3b and 3c is that in the fourth embodiment of fig. 4, the heat exchange tube 40 further includes at least one reinforcing rib 190. Reinforcing ribs 190 may be provided in the heat exchange flow channel 140. In some examples, at least one of the reinforcing ribs 190 may have a bar-shaped structure, which may extend, for example, in the extending direction of the heat exchange flow channel 140 of the heat exchange tube 40, and may be disposed in parallel with the outer and/or inner baffles. In other examples, the strip-shaped structures may be arranged in an S-shape or Z-shape within the heat exchange tube 40. In still other examples, at least one of the reinforcing ribs 190 may also have a cylindrical structure, and is dispersedly disposed in the heat exchange flow channel 140 of the heat exchange tube 40. For example, the cylindrical structure may support the first and second panels 111 and 112 of the heat exchange pipe 40 at a plurality of positions in a pillar manner.

In an embodiment of the present invention, the reinforcing rib 190 may be coupled with at least one of the first panel 111 and the second panel 112 by the adhesive 160. The reinforcing ribs 190 have the effects of supporting the first panel 111 and the second panel 112, reinforcing the disturbance of the heat exchange medium, and enhancing the heat transfer, and also have the effects of improving the strength of the heat exchange tube 40 and improving the pressure bearing capability.

In the embodiments described above, the heat exchange pipe according to the present invention is a gas-gas heat exchange pipe, for example, a heat exchange pipe 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 may be any gas for heat exchange, and the heat exchange medium outside the heat exchange tube is not limited to flue gas but may be any gas for heat exchange.

According to the embodiments of the invention, the inner pipeline of the heat exchange pipe comprises the heat exchange flow channel and the heat insulation channel, so that the corrosion resistance of the heat exchange pipe is ensured, and the temperature resistance of the heat exchange pipe can be improved.

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 channel, which can ensure a larger heat exchange area. If the heat exchange medium does leak due to the over-temperature, the leakage generally occurs between the outer baffle and the first and second panels, that is, only the heat exchange medium flowing through the heat insulation passage leaks, and thus the amount of leakage is small.

According to the embodiments of the invention, when the heat exchange pipe leaks in a large area, the leaked heat exchange pipe can be independently plugged or replaced.

According to the embodiments of the invention, the first sealing element and the second sealing element are made of metal aluminum, and are easy to process and manufacture.

An embodiment of a heat exchanger according to the invention is described below with reference to fig. 5.

Fig. 5 is a schematic view of a heat exchanger including a heat exchange tube according to the present invention. As shown in fig. 5, according to an embodiment of the present invention, a heat exchanger 1 may include a shell 2 and a plurality of heat exchange tubes 3. The housing 2 may, for example, be substantially box-shaped. The housing 2 may comprise two mounting plates 4 arranged opposite in the X-direction. Each of the mounting plates 4 has a plurality of first through holes (not shown) formed therein. The housing 2 is formed with second through holes (not shown) on two oppositely disposed side surfaces perpendicular to the mounting plate 4 (i.e., two side surfaces of the housing 2 in the Y direction). Both ends of each heat exchange tube 3 are hermetically connected to corresponding first through holes of the mounting plate 4, respectively, to provide 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 tube 10, 20, 30, 40 described in the above embodiments.

As shown in fig. 5, a heat exchange medium such as low-temperature air may enter the heat exchange tubes 3 from the mounting plate 4 on one side in the X direction (e.g., the left side in fig. 5). A heat exchange medium such as low-temperature air exchanges heat with a heat exchange medium such as high-temperature flue gas outside the heat exchange tubes 3 while flowing through the heat exchange tubes 3, and then flows out from the mounting plate 4 on the other side (e.g., the right side in fig. 5). A heat exchange medium (e.g., high temperature flue gas) outside the heat exchange tube 3 may enter a space between the heat exchange tube 3 and the casing 2 from the second through hole of one side (e.g., the front side in fig. 5) of the casing 2 in the-Y direction, exchange heat with the heat exchange medium (e.g., low temperature air) inside the heat exchange tube 3 while passing through the space between the heat exchange tube 3 and the casing 2, and then flow out from the second through hole of the other side (e.g., the rear side in fig. 5) of the casing 2.

When the heat exchange tubes 3 are used for assembly to form the heat exchanger 1, the mounting plate 4 for mounting the heat exchange tubes 3 generally has a through-hole for allowing the heat exchange tubes 3 to pass therethrough and fixing one end of the heat exchange tubes 3. With reference to fig. 3a, 3b and 3c and fig. 5, the heat exchanger 1 may further include: and a first sealing member 181 and a second sealing member 182 disposed opposite to each other at both sides of each heat exchange tube 3, wherein the first panel 111, the second panel 112, the first sealing member 181 and the second sealing member 182 form an external shape in conformity with the shape of the first through-hole of the mounting plate 4, thereby sealing the first through-hole. The first and second sealing members 181 and 182 extend along the extending direction (e.g., X direction) of the heat exchange flow channel 140 of the heat exchange tube 3, and have a dimension in the extending direction greater than the thickness of each mounting plate 4, so that the first and second sealing members 181 and 182 seal the first through-holes.

In an embodiment of the present invention, the first and second seals 181 and 182 include an abutting portion including two abutting faces for abutting against the first and second panels 111 and 112 in parallel with each other, and a side blocking portion extending perpendicular to the abutting faces of the abutting portion, so that the first and second seals 181 and 182 have a T-shaped cross-sectional shape.

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

The foregoing description is only exemplary of the preferred embodiments of the invention and is illustrative of the principles of the technology employed. It will be appreciated by those skilled in the art that the scope of the invention herein disclosed is not limited to the particular combination of features described above, but also encompasses other arrangements formed by any combination of the above features or their equivalents without departing from the spirit of the invention. For example, the above features and (but not limited to) features having similar functions disclosed in the present invention are mutually replaced to form the technical solution.

Claims (18)

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 inside baffle is used for enclosing the first panel and the second panel to form a heat exchanging channel on the opposite side of the outside baffle, and the outside baffle is arranged on the outer side of the inside baffle and is used for enclosing the inside baffle and the first panel and the second panel to form an insulating channel so as to block heat transfer from the outside baffle to the inside baffle.

2. The heat exchange tube of claim 1, wherein the ratio of the width of the insulating channel to the width of the heat exchange flow channel is less than or equal to 1:10, preferably 1:30 to 1: 20.

3. A heat exchange tube according to claim 1 or 2, wherein the width of the insulating channel is less than or equal to 10mm, preferably less than or equal to 8mm, more preferably less than or equal to 5 mm.

4. A heat exchange tube according to claim 3, wherein the width of the insulating channel is greater than or equal to 1mm, preferably greater than or equal to 2mm, more preferably greater than or equal to 3mm, to allow the circulation of a heat exchange medium inside the insulating channel.

5. The heat exchange tube of claim 1, wherein the outer and inner side baffles are separate from at least one of the first and second panels and are joined together by an adhesive.

6. The heat exchange tube of claim 1, wherein the width of the outside baffle is less than the width of the inside baffle.

7. A heat exchange tube according to claim 1, wherein the ratio of the sum of the widths of the outer baffle, inner baffle and insulation channel to the widths of the first and second panels is less than or equal to 1:5, preferably less than or equal to 1: 10.

8. The heat exchange tube of claim 1 wherein the outboard and inboard baffles are disposed on a first side of the first and second panels, and the heat exchange tube further comprises a single, opposite side baffle disposed on a second side opposite the first side for enclosing the first and second panels to form a heat exchange manifold.

9. The heat exchange tube of claim 1, wherein the inside baffles comprise a first inside baffle and a second inside baffle, the outside baffles comprise a first outside baffle and a second outside baffle,

the first inboard flap being disposed between the first outboard flap and the second inboard flap, the second inboard flap being disposed between the first inboard flap and the second outboard flap,

the first outer side baffle, the first inner side baffle, the first panel and the second panel surround to form a first heat insulation channel, and the second outer side baffle, the second inner side baffle, the first panel and the second panel surround to form a second heat insulation channel.

10. The heat exchange tube of claim 9, wherein the width of the first insulating channel is greater than the width of the second insulating channel.

11. The heat exchange tube of claim 9, wherein the first panel, the second panel, the first inside baffle, the second inside baffle, the first outside baffle, and the second outside baffle are each separate components, and the first panel and the second panel are each sealingly joined together with the first inside baffle, the second inside baffle, the first outside baffle, and the second outside baffle by an adhesive.

12. The heat exchange tube of claim 1, wherein the heat exchange tube is a gas-to-gas heat exchange tube.

13. A heat exchanger, comprising:

the shell comprises two opposite mounting plates, a plurality of first through holes are formed in the mounting plates respectively, and second through holes are formed in two opposite side surfaces perpendicular to the mounting plates; and

a plurality of heat exchange tubes, both ends of each heat exchange tube are respectively connected to the corresponding first through holes of the mounting plate in a sealing manner,

wherein at least one of the plurality of heat exchange tubes is a heat exchange tube according to any one of claims 1 to 12.

14. The heat exchanger of claim 13, further comprising: and a first sealing member and a second sealing member which are disposed opposite to each other at both sides of each heat exchange pipe, wherein the first panel, the second panel, the first sealing member and the second sealing member form an external shape in conformity with the shape of the first through-hole of the mounting plate.

15. The heat exchanger according to claim 14, wherein the first and second seals extend along an extending direction of the heat exchange flow channel of the heat exchange tube, and a dimension in the extending direction is larger than a thickness of each mounting plate.

16. The heat exchanger of claim 15, wherein the first and second seals include abutment portions including two mutually parallel abutment faces for abutment against the first and second panels and a skirt portion extending perpendicular to the abutment faces of the abutment portions such that the first and second seals have a T-shaped cross-sectional shape.

17. The heat exchanger according to any one of claims 14 to 16, wherein the first and second seals are sealingly joined together with the first and second panels, respectively, by an adhesive, and the first and second seals are made of metallic aluminum.

18. The heat exchanger of claim 13, wherein the heat exchanger is an air preheater.

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