WO2019114325A1

WO2019114325A1 - Heat exchange tube, heat exchanger and air conditioner

Info

Publication number: WO2019114325A1
Application number: PCT/CN2018/103229
Authority: WO
Inventors: 刘华; 岳清学; 胡东兵; 张营; 杨旭峰
Original assignee: 格力电器（武汉）有限公司; 珠海格力电器股份有限公司
Priority date: 2017-12-11
Filing date: 2018-08-30
Publication date: 2019-06-20
Also published as: CN109900151B; CN109900151A

Abstract

A heat exchange tube, a heat exchanger and an air conditioner, the heat exchange tube comprising a tube body (1), fins (2) being circumferentially provided on an outer wall of the tube body (1), a part of the circumferential region of each fin (2) being provided with protrusions, and the other part of the circumferential region of each fin (2) forming a smooth fin segment (6). By providing protrusions on the fins (2), such heat exchange tube can reduce the thickness of the liquid film adhered to the surface of the fins (2), so as to increase the heat exchange surface area, and this structure can enhance the local phase-change heat exchange capability thereof; meanwhile, the smooth fin segment (6) can reduce the liquid flow resistance and allow the liquid to flow out smoothly, preventing the liquid film from accumulating on the surface of the fins (2) which reduces the circumferential heat exchange area and increases the heat resistance, thereby comprehensively improving the overall heat exchange effect of the heat exchange tube.

Description

Heat exchange tube, heat exchanger and air conditioner

Related application

This application claims the benefit of priority to the benefit of the benefit of the benefit of the benefit of the benefit of the benefit of the benefit of the benefit of the benefit of the benefit of the benefit of the benefit of the benefit of the benefit of the benefit of the benefit of the benefit of the benefit of the benefit of the benefit of the benefit of the disclosure.

Technical field

The present application relates to the technical field of air conditioners, and in particular, to a heat exchange tube, a heat exchanger, and an air conditioner.

Background technique

In the refrigeration and air conditioning industry, water-cooled condensers have developed rapidly due to their compact structure and wide applicability. Most of the water-cooled heat exchangers are shell-and-tube heat exchangers. In the condenser, one of the factors that has a large influence on the heat transfer is the performance of the heat exchange tubes in the casing. During the heat exchange process of the condensation tube, the gaseous refrigerant outside the condensation tube exchanges heat with the internal water through the phase change. Since the thermal resistance of the condensation tube mainly exists outside the tube, according to the weak side strengthening principle, the external reinforcement of the tube appears. It is especially important to minimize the thermal resistance outside the tube to improve heat transfer performance.

In order to achieve this, the condensing tube generally spirally processes the metal into fins on the circumference of the pipe body to increase the heat exchange area thereof, and performs secondary rolling on the entire circumference of the top of the spiral fin to form a boss or a sharp corner. First, the surface area outside the tube is further increased. Secondly, due to the formed boss or sharp corner, the thickness of the liquid film condensed on the surface of the fin can be reduced, the thermal resistance is lowered, and the heat transfer performance of the condensing tube is improved. However, in actual use, it was found that such a condenser tube failed to achieve a high heat exchange efficiency of the condenser, and thus further improvement was required.

Summary of the invention

The purpose of the application is to propose a heat exchange tube, a heat exchanger and an air conditioner, which can improve the heat exchange capacity of the heat exchange tube.

In order to achieve the above object, a first aspect of the present application provides a heat exchange tube including a tube body. The outer wall of the tube body is provided with fins in the circumferential direction, and a convex portion is provided on a part of the circumferential area of the fin. The remaining portion of the circumferential region forms a smooth fin segment.

Further, the fins are spirally distributed on the outer wall of the tubular body.

Further, the region on the fin where the projection is provided forms a first continuous region in the circumferential direction, and the smooth fin segment forms a second continuous region in the circumferential direction.

Further, the smoothing fin segments correspond to an angular range of 180° or less in the circumferential direction of the tubular body.

Further, a plurality of sets of protrusions are included in the region where the fins are provided with the protrusions, and the plurality of sets of protrusions are spaced apart in the circumferential direction of the fins.

Further, the circumferential direction of the fin includes a first continuous area and a second continuous area, wherein the first continuous area is provided with a plurality of sets of protrusions, and the plurality of sets of protrusions are arranged along the circumferential direction of the fins, and the second The continuous area is a smooth fin segment.

Further, the local position of the smooth fin segment is provided with a projection.

Further, the circumferential direction of the fin includes a first continuous region and a second continuous region, wherein the first continuous region is a continuous region provided with a convex portion along a circumferential direction of the fin, and the second continuous region is a smooth wing segment, smooth wings The partial position of the segment is provided with a projection.

Further, in a state where the heat exchange tubes are installed in the condenser, the first continuous area is disposed upward, and the second continuous area is disposed downward.

Further, the free end of the projection has a sharp portion.

Further, at least two layers of projections are provided in the radial height direction of the fins.

Further, at least two layers of projections are staggered along the circumferential direction of the tubular body.

Further, the at least two protruding portions include a first layer protruding portion and a second layer protruding portion, and the top of the fin is formed into a pressing groove by knurling, and both ends of the pressing groove are extended to the outside of the fin to form a first layer convex portion. In the outlet portion, the second layer projecting portion is located radially inward of the first layer projecting portion, and the second layer projecting portion is formed by knurling.

Further, each of the second layer projections is located on the same side of the fin.

Further, the pressure groove is disposed obliquely with respect to the axis of the pipe body.

Further, the first layer projections on the adjacent fins are offset from each other in the circumferential direction of the tube body.

Further, the end of the pressure groove along its own length direction is triangular, trapezoidal or rectangular; and/or the pressing surface of the second layer projection is triangular, trapezoidal or rectangular.

Further, the inner wall of the pipe body is provided with a spiral convex thread.

Further, the raised threads are multi-start threads.

Further, the cross section of the convex thread has a trapezoidal or triangular shape.

Further, the fins are integrally provided on the tubular body, and/or the protruding portions are integrally provided on the fins.

Further, at least one of the fins and the projections is formed by extrusion.

Further, the angle at which the smooth fin segments correspond in the circumferential direction of the tube body is in the range of 1/7 to 1/2 in the entire circumferential direction.

Further, the trough body 3 is formed between the adjacent fins, the bottom of the trough body is smooth, and the intersection of the bottom of the trough body and the fin is rounded; or the whole bottom of the trough body has a smooth transition.

Further, the angle between the fin and the plane perpendicular to the axis of the tube body is α = 0.3° to 3.0°.

Further, the thickness h7 of the fin is 0.1 to 0.252 mm, and the width h8 of the groove formed between the adjacent fins is 0.252 to 0.558 mm.

Further, the depth h1 of the groove from the top of the fin is 0.1 to 0.45 mm, or the width of the groove is h2=0.01 to 0.35 mm, or the length of the first layer protrusion extending toward the side of the fin is h3=0.05. 0.2mm.

Further, the angle between the inclination direction of the groove and the extending direction of the top of the fin is β=15° to 65°.

Further, a width h4=0.05-0.2 mm of the second layer protrusion extending outward relative to the surface of the fin, or a step height h5=0.15-0.45 mm formed by the bottom of the second layer protrusion and the root of the tube body, or The width of the second layer projection in the circumferential direction of the fin is h6 = 0.05 to 0.32 mm.

Further, the number of the groove grooves n2 = 35 to 100 is provided on the single-circle fin 2; or the number of the second layer projections on the side faces of the single-turn fin 2 is n3 = 35 to 100.

Further, the inclination angle of the convex thread with respect to the axis of the tube body is α1=15-55°, or the convex height of the convex thread on the inner wall of the tube is h9=0.15-0.55 mm, or two of the sections of the convex thread The angle formed by the side is γ=15-65°; or the convex thread is a multi-start thread, and the multi-start thread is distributed n1=10-80 on the entire circumference of the inner wall of the tube.

In order to achieve the above object, a second aspect of the present application provides a heat exchanger comprising the heat exchange tube of the above embodiment.

Further, the heat exchanger is a condenser.

Further, the region on the fin where the projection is provided is a continuous region in the circumferential direction, and after the heat exchange tube is mounted, the region of the fin with the projection is disposed upward, and the smooth fin segment is disposed downward.

In order to achieve the above object, a third aspect of the present application provides an air conditioner comprising the heat exchanger of the above embodiment.

Based on the above technical solution, the heat exchange tube of the embodiment of the present application has a convex portion on a circumferential portion of the outer fin of the heat exchange tube, and the circumferential portion of the remaining portion of the fin forms a smooth fin segment, which is generated after heat exchange. The liquid can be exported through a trough between adjacent smooth fin segments. The heat exchange tube can reduce the thickness of the liquid film adhered on the surface of the fin by adding a protrusion on the fin, and increase the heat exchange surface area, and the structure can enhance the local phase change heat capacity; at the same time, smooth The fin segment can reduce the liquid flow resistance and make the liquid flow smoothly, so as to prevent the liquid film from accumulating on the surface area of the fin to reduce the circumferential heat exchange area and increase the thermal resistance, thereby comprehensively improving the overall heat exchange effect of the heat exchange tube.

DRAWINGS

The drawings described herein are intended to provide a further understanding of the present application, and are intended to be a part of this application. In the drawing:

1 is a schematic structural view of an embodiment of a heat exchange tube of the present application;

2 is a schematic view showing the structure of a fin of a heat exchange tube according to an embodiment of the present invention;

Figure 3 is a side elevational view of the fin of the heat exchange tube of the present application in a circumferential direction;

Figure 4 is a partial cross-sectional view showing an embodiment of the heat exchange tube of the present application;

Figure 5 is a plan view of an embodiment of the heat exchange tube of the present application after being deployed in the circumferential direction;

Figure 6 is a full cross-sectional view of one embodiment of a heat exchange tube of the present application.

Description of the reference numerals

1. Tube body; 2. Fin; 3. Groove body; 4. First layer protrusion; 5. Second layer protrusion; 6. Smooth fin section; 7. Press groove; 11, a winged section; 12, a smooth section; 13, a transition section.

Detailed ways

The present application is described in detail below. In the following paragraphs, different aspects of the embodiments are defined in more detail. Aspects so defined may be combined with any other aspect or aspects unless clearly indicated that they are not combinable. In particular, any feature that is considered to be preferred or advantageous may be considered as a preferred or advantageous feature with the other one or more.

The terms "first", "second" and the like appearing in the present application are merely for convenience of description to distinguish different components having the same name, and do not indicate sequential or primary or secondary relationships.

In the description of the present application, it is to be understood that the terms "upper", "lower", "left", "right", "front", "rear", "circumferential", "axial" and "radial" are understood. The orientation or positional relationship of the instructions is based on the orientation or positional relationship shown in the drawings, and is merely for the convenience of describing the present application, and does not indicate or imply that the device referred to must have a specific orientation, constructed and operated in a specific orientation. Therefore, it should not be construed as limiting the scope of the application.

During the use, the applicant found that even if more bosses or sharp corners are added on the spiral fins outside the heat exchange tubes, it is difficult to obtain ideal heat exchange performance during the condensation process. Therefore, the applicant performs the heat exchange process of the condenser tubes. Research. In the heat transfer test of the condensing tube, it is found that during the condensation heat exchange process, most of the gaseous refrigerant is condensed on the upper outer surface of the condensing tube in the circumferential direction, and then the liquid refrigerant formed by the condensation flows along the passage between the fins. Go under the condenser and drain away from the bottom of the condenser.

In the prior art condensing tube, in the intensified condensation process of the external phase change heat of the tube, the density of the fins or the number of sharp portions is generally increased by the chipless processing extrusion molding technique to enhance the condensation effect, and the top portion of the fin is processed. A sharp protrusion is formed. Because according to the usual idea, this method can increase the heat exchange surface area, and can greatly thin the refrigerant liquid film condensed on the fins, reduce the thermal resistance, thereby improving the heat transfer performance of the condensing tube. However, the Applicant noticed that the increased boss and sharp corners on the surface of the fin also increased the resistance of the liquid film to drip and discharge, and could not smoothly flow away from the bottom of the heat exchange tube, causing the liquid film to exist on the fin surface area. Thickening the liquid film will increase the thermal resistance and affect the heat transfer performance.

Therefore, the applicant has conducted in-depth research on the strengthening mechanism of the condensation tube: on the one hand, it is necessary to reduce the liquid film directly adhered to the fins on the outer surface of the condensation tube when the refrigerant is condensed, so as to reduce the thermal resistance and improve the heat exchange performance; On the other hand, it is necessary to drain the liquid refrigerant condensed on the surface of the condensing pipe in time to prevent the liquid refrigerant from accumulating on the heat exchange surface to thicken the liquid film and increase the thermal resistance. However, there are constraints in these two aspects, and it is difficult to take care of both. In this way, increasing the number of sharp portions on the surface alone is a misunderstanding in improving the heat exchange performance. Moreover, when the number of sharp portions formed by the surface knurling is increased, the knurling portion of the mold is reduced in the case where the circumferential dimension is constant. Thin, the strength of the hobbing in the mold will be reduced, and the phenomenon of mold collapse will be prone to occur, thereby increasing the processing difficulty and cost of the mold.

According to this idea, the purpose of the present application is to simultaneously consider the problem of thinning the liquid film to enhance the heat exchange and the timely discharge of the refrigerant liquid, so as to improve the overall heat exchange effect of the condenser tube. Such a condenser tube can be used in the evaporator as well as in the evaporator, and is therefore collectively referred to as a heat exchange tube.

In an exemplary embodiment, as shown in FIG. 1, the heat exchange tube of the present application includes a pipe body 1. The outer wall of the pipe body 1 is provided with fins 2 in the circumferential direction, and adjacent ring fins along the axial direction of the pipe body 1. A groove 3 is formed between the sheets 2. For example, the pipe body 1 is a circular pipe, the fins 2 are spirally distributed on the outer wall of the pipe body 1, or a plurality of annular fins 2 are spaced apart on the outer wall of the pipe body 1. Alternatively, the cross section of the pipe body 1 may also be selected from a desired shape such as an ellipse, a rectangle or a polygon. The fin 2 is provided with a projection only in a part of the circumferential area, and a smooth fin section 6 on the remaining partial circumferential area, that is, a projection is not provided on the surface of the fin 2, and a liquid passage phase generated after condensation heat exchange is obtained. The trough 3 between the adjacent smooth fin segments 6 flows out. The protruding portion may be a boss or a sharp corner provided on the surface of the fin 2, and the shape thereof is not limited. Preferably, the projection is provided on the side of the fin 2.

Such a heat exchange tube is preferably used in a horizontal condenser, the heat exchange tube is horizontally installed, the heat exchange tube is internally filled with a fluid to be heated, and the outside is filled with a gaseous refrigerant, for example, water or Freon as a refrigerant. Preferably, when the heat exchange tube is mounted, the region of the fin 2 on which the projection is provided is located above, and the smooth fin segment 6 is located below.

In the heat exchange process, most of the gaseous refrigerant is condensed on the upper outer surface of the heat exchange tube in the circumferential direction, and the fins 2 in the upper portion of the heat exchange tube are provided with protrusions, since the protrusions are higher than the surface of the fins 2, The curvature of the convex portion with respect to the surface of the fin is increased, and the thickness of the liquid film adhered to the surface of the fin 2 can be thinned, and the heat exchange surface area is also increased, so that the upper portion of the outer surface of the heat exchange tube can be performed. Heat transfer enhancement. In the lower region of the heat exchange tube, the ability to thin the liquid film is weakened, the heat transfer strengthening effect on the fin 2 is weakened, and the liquid refrigerant in the condensed liquid flows downward under gravity, and the liquid refrigerant can be reduced in the tank body. The resistance of the flow in 3 enhances the ability of the liquid refrigerant to flow downward along the tank body 3, so that the liquid refrigerant smoothly flows out of the tank body 3, so as to prevent the liquid film from accumulating on the surface of the fin 2, thereby comprehensively improving the heat exchange tube. Overall heat transfer effect.

The heat exchange tube of the present application solves the problem of discharge of liquid refrigerant in the condensation process, reduces the attenuation of the overall heat exchange performance of the protruding portion in the lower portion of the fin of the heat exchange tube, and strengthens and strengthens the part of the heat exchange tube. The condensing and discharging effect is optimized, and the problem that the heat exchange tube is thinned by the liquid film during the condensation process and the liquid refrigerant is discharged in time is taken into consideration. For the heat exchange tube of the present application, the conventional idea in the prior art is broken, and there is no need to focus on the problem of increasing the number of protrusions on the fins, and the strength of the hobbing can be ensured when the knurling mold is made, so as to avoid appearing. The phenomenon of chipping can reduce the processing difficulty and processing cost.

In a preferred embodiment, as shown in Fig. 1, the region of the fin 2 on which the projection is provided forms a first continuous region in the circumferential direction, and the smooth fin segment 6 forms a second continuous region. Such an arrangement can provide as many protrusions as possible in the region where the pipe body 1 is used for condensation without increasing the degree of local density of the projections, thereby reducing the thickness of the liquid film and improving the heat exchange capability. For example, as in the embodiment shown in FIG. 1, when the heat exchange tubes are installed in the condenser, the first continuous region on the fins 2 on which the projections are provided is located in the upper region of the fins 2, corresponding to the smooth fin segments 6. The second continuous region is located in the lower region of the fin 2.

For the embodiment shown in Fig. 1, preferably, the smooth fin segments 6 correspond to an angular range of 180° or less in the circumferential direction of the tubular body 1. This arrangement can increase the number of protrusions on the fins 2 as much as possible while ensuring the discharge capacity of the heat exchange tubes, so as to reduce the thickness of the liquid film and improve the heat exchange capacity. More preferably, the angle at which the smooth fin segments 6 correspond in the circumferential direction of the tubular body 1 is in the range of 1/7 to 1/2 in the entire circumferential direction.

In another optional embodiment, a plurality of sets of protrusions are included in the region of the fin 2 on which the protrusion is provided, and the plurality of sets of protrusions are spaced apart in the circumferential direction of the fin 2, and correspondingly, the smooth wing The segments 6 also form a structure that is spaced apart. For example, based on the embodiment shown in Fig. 1, the projections in the upper region of the fin 2 are arranged in a plurality of groups along the circumferential direction of the fins 2, and a plurality of sets of projections are spaced apart. The plurality of sets of protrusions on the heat exchange tube can also increase the surface area of the tube body 1, and simultaneously reduce the thickness of the liquid film condensed on the surface of the fin, reduce the thermal resistance, and improve the heat transfer performance of the condensing tube.

Preferably, the circumferential direction of the fin 2 includes a first continuous area and a second continuous area, wherein the first continuous area is provided with a plurality of sets of protrusions, and the plurality of sets of protrusions are spaced apart in the circumferential direction of the fin 2, The second continuous region is a smooth fin segment 6. Taking the structure shown in FIG. 1 as an example, the first continuous region is the upper region of the fin 2, and in the upper region, a plurality of sets of protrusions are provided in the circumferential direction, the second continuous region is the lower region of the fin 2, and the lower region is smooth. Wing fragment 6.

In still another alternative embodiment, a projection is added at a local location of the smooth fin segment 6. For example, based on the embodiment shown in Fig. 1, a small number of projections are added to the smooth fin segments 6 in the lower region of the tubular body 1, as long as the condensed water does not have a large influence on the flow out of the trough body 3, and is in the protection range. within. The heat exchange tube can still reduce the liquid flow resistance, so that the liquid flows out smoothly, so as to prevent the liquid film from accumulating on the fin surface area to reduce the circumferential heat exchange area and increase the thermal resistance, thereby comprehensively improving the overall heat exchange effect of the heat exchange tube.

Preferably, the circumferential direction of the fin 2 includes a first continuous region and a second continuous region, wherein the first continuous region is a continuous region provided with a projection along the circumferential direction of the fin 2, and the second continuous region is a smooth fin segment 6 And a convex portion is added to a local position of the smooth fin segment 6. Taking the structure shown in FIG. 1 as an example, the first continuous region is an upper region of the fin 2, the upper region is a continuous region provided with a projection along the circumferential direction of the fin 2, and the second continuous region is a lower region of the fin 2, and a lower portion The region is a smooth fin segment 6, and a small number of projections can be added at a local position of the smooth fin segment 6.

In addition to the above embodiments, alternatively, the structural forms of the first continuous region and the second continuous region may be arbitrarily combined. Further, it is also within the scope of the present application to provide a region in which the projections are provided on the fins 2 and the entire smooth fin segments 6 are intermittently spaced (for example, evenly spaced).

As shown in Fig. 1, such a heat exchange tube forms a boundary structure between the region where the projections are provided on the fins 2 and the smooth fin segments 6, and is used to realize the transition of the two regions. Preferably, the boundary structure is jagged, spiral, stepped or stepped, etc., all within the scope of protection of the present application.

The structure of the projections on the fins 2 will be described below. In order to more clearly illustrate the structure and arrangement of the projections, the heat exchange tubes shown in FIG. 1 are deployed in the circumferential direction, FIG. 2 is a schematic view showing a partial structure of the fins 2, and FIG. 3 is a fin 2 Side view of the structure.

Preferably, the free end of the projection has a sharp portion, which facilitates stretching of the liquid film during the downward flow of the liquid, thinning the thickness of the liquid film, and enhancing the effect of local condensation. Alternatively, the projection can also be designed as a boss structure, and the free end of the projection is a smooth transition structure.

In order to increase the number of projections to increase the ability to thin the liquid film, preferably, as shown in a partial cross-sectional view as shown in FIG. 4, at least two projections are provided in the radial height direction of the fin 2. Of course, it is also within the scope of the present application to provide only one layer of protrusions in the radial height direction of the fins 2.

As shown in FIGS. 1 to 3, at least two layers of projections are arranged offset along the circumferential direction of the tubular body 1. For example, the fins 2 of the heat exchange tube shown in FIG. 1 are provided with two layers of protrusions, and the two layer protrusions are alternately spaced in the circumferential direction of the tube body 1 so that the protrusions are in the circumferential direction of the heat exchange tubes. The area is evenly distributed, and the liquid film can be thinned evenly at the same time, so that the heat resistance of the heat exchange tube is evenly distributed, thereby improving the heat exchange uniformity of the heat exchange tube and improving the overall heat exchange capacity. Moreover, this arrangement also provides space for the hob to process the lower projections, facilitating the processing of the multi-layer projections. Alternatively, it is also within the scope of the present application to have at least two of the projections facing each other.

Preferably, as shown in FIG. 4, at least two layers of protrusions include a first layer protrusion 4 and a second layer protrusion 5, and the second layer protrusion 5 is located below the first layer protrusion 4.

Here, as shown in Fig. 3, the formation of the first layer projecting portion 4 is performed by secondary squeezing at the top of the original fin 2 by means of a knurling die. Specifically, the groove 7 is formed by knurling in the width direction at the top of the fin 2, and the groove 7 can be inclined with respect to the axis of the pipe body 1, and at the same time, the ends of the groove 7 are winged due to the good plasticity of the metal itself. The outer side of the sheet 2 is stretched to form a first layer of projections 4. Preferably, referring to the side view of the rearwardly extending fin shown in FIG. 3, the end surface of the top groove 7 of the fin 2 has an inverted triangular shape, a trapezoidal shape or a rectangular shape, and the end surface shape of the pressure groove 7 is assumed to be closed at the top. In the case, it is formed by the bottom of the pressure groove 7, the inner side wall, and the top surface. In the plan view in which the fins are circumferentially expanded in FIG. 5, the pressure groove 7 is inclined with respect to the axis of the pipe body 1, and both sides of the fin 2 are serrated, and the first layer projecting portion 4 has a triangular structure.

Alternatively, as shown in FIG. 5, the angle between the inclined direction of the groove 7 and the direction in which the fins 2 extend is β=15° to 65°. As shown in FIG. 3, the number of the grooves 7 on the single-turn fin 2 is n2 = 35 to 100.

Optionally, as shown in FIG. 4 and FIG. 5, the depth of the groove 7 from the top of the fin 2 is h1=0.1-0.45 mm, or the width of the groove 7 is h2=0.01-0.35 mm, or the first layer protrusion 4 The length h3 extending toward the side surface of the fin 2 is 0.05 to 0.2 mm.

As shown in FIG. 3, the second layer projecting portion 5 is located radially inward of the first layer projecting portion 4, and the second layer projecting portion 5 is formed by knurling. Preferably, the pressing faces of the second layer projections 5 are inverted triangles, trapezoids or rectangles, and the like. The second layer projecting portion 5 is formed by extrusion on one side of the fin 2 without additional weight, while increasing the surface area of the fin 2. The liquid film can be further stretched during the downward flow of the liquid refrigerant to reduce the thickness of the liquid film and enhance the local condensation effect.

Preferably, each of the second layer projections 5 is located on the same side of the fin 2. As shown in FIG. 5, a second layer projecting portion 5 is provided on the right side surface of the fin 2, and the second layer projecting portion 5 has a triangular shape and has a sharp portion. This can reduce the width occupied by the second layer projections 5 in the groove 3 between the adjacent fins 2, in order to retain a wide liquid flow passage, and minimize the liquid flow while thinning the liquid film. The resistance you receive.

Optionally, as shown in FIG. 2 and FIG. 3, the width of the second layer protruding portion 5 extending outward relative to the surface of the fin is h4=0.05-0.2 mm, or the bottom of the second layer protruding portion 5 and the tube body 1 The step height h5 formed by the root portion is 0.15 to 0.45 mm, or the width h6 of the second layer projecting portion 5 in the circumferential direction of the fin 2 is 0.05 to 0.32 mm. The number n3 of the second layer projections 5 formed on the side faces of the single-turn fins 2 is 35 to 100.

Preferably, as shown in FIG. 1, the first layer projections 4 on the adjacent fins 2 are offset from each other in the circumferential direction of the pipe body 1, and correspondingly, the second layer projections on the adjacent fins 2 are correspondingly arranged. 5 is also arranged offset from each other in the circumferential direction of the pipe body 1. Such an arrangement can make the layout of the first layer protruding portion 4 on the heat exchange tube more uniform, improve the uniformity of the thinned liquid film, and enhance the heat exchange effect.

For the inside of the heat exchange tube, referring to FIG. 4, the outer teeth of the ribs are extruded on the inner wall of the pipe body 1 by the extrusion of the outer tube and the circumferentially grooved mold matched with the inner side, which can increase the heat exchange. The disturbance of the internal fluid of the tube also increases the heat exchange area.

Preferably, the inner wall of the tubular body 1 is provided with a helical projection thread 8. While the outer fins 2 are being processed, the heat exchange tubes are rolled into the tubes by the grooved cores in the tubes.

As shown in FIG. 4, the protruding thread 8 has a trapezoidal-like or inverted triangular structure, and the top portion is integrally formed with the tubular body 1, and the bottom corners are smoothly transitioned, and the convex root portion and the inner wall of the tubular body 1 are smoothly transitioned. Strengthening the inner wall of the heat exchange tube not only increases the surface area inside the tube, but also forms a certain protrusion with the inner wall of the tube, which increases the degree of disturbance of the fluid in the tube, thereby further enhancing the heat exchange effect.

Optionally, as shown in FIG. 4, the inclination angle α1=15-55° of the convex thread 8 with respect to the axis of the tube body 1, and the convex height h9 of the convex thread 8 on the inner wall of the tube body is 0.95 to 0.55. Mm, the angle formed by the two sides of the profile of the raised thread 8 is γ=15-65°.

The raised threads 8 in the tube may be evenly distributed or non-uniformly distributed. The non-uniformity distribution has better perturbation effect on the fluid in the tube to enhance the heat exchange effect. For example, the convex thread 8 is a multi-start thread, the multi-start thread processing efficiency is high, and the spacing between adjacent convex threads 8 in the entire tube body 1 is uniform or not completely uniform, and the disturbance effect on the fluid can be increased. Alternatively, the multi-start thread is distributed n1 = 10 to 80 over the entire circumference of the inner wall of the pipe body 1.

For each of the above embodiments, the fins 2 may be integrally provided on the tubular body 1, and the projections may be integrally provided on the fins 2. The integrated arrangement can reduce the contact thermal resistance to improve the heat exchange efficiency of the heat exchange tubes. Preferably, at least one of the fins 2 and the projections is formed by extrusion, and the weight of the heat exchange tubes can be increased without additional.

In a specific embodiment, as shown in FIG. 1 and FIG. 6, the heat exchange tube is processed on a dedicated fin rolling mill, and an extrusion-molding chip-free processing process is used, and the heat exchange tube is strengthened outside the tube. The combination of the tool combination and the knurling die is extruded, and the inner reinforcement is formed by simultaneous rolling of the fins on the outer side by the groove die, and the double-side strengthening can be simultaneously performed.

For example, a mother tube having an outer diameter of 19.05 mm and a wall thickness of 1.13 mm can be used for processing. The fins 2 having a certain spiral angle on the base pipe are machined by a combined mold outside the tube. As shown in Fig. 1, the tubular body 1 may include an unprocessed smooth section 12 and a finned section 11 processed with fins 2, which may be respectively provided at both ends of the finned section 11 in consideration of installation and heat exchange requirements. The smooth section 12 is used to realize the installation of the heat exchange tubes, and the transition section 13 can be connected between the smooth section 12 and the finned section 11. Wherein, the fins 11 are processed with the fins 2, and the adjacent fins 2 are formed with the trough 3, the bottom of the trough 3 is smooth, and the intersection of the bottom of the trough 3 and the fins 2 is smoothly transitioned; The whole bottom of the tank body 3 has a smooth transition, and this arrangement is advantageous for the refrigerant to flow away.

Alternatively, as shown in Fig. 1, the angle between the fin 2 and the plane perpendicular to the axis of the tubular body 1 is α = 0.3° to 3.0°. Alternatively, as shown in FIG. 2, the thickness of the fin 2 is h7 = 0.1 to 0.252 mm, and the width of the groove 3 formed between the adjacent fins 2 is h8 = 0.252 to 0.558 mm.

Then, the fins 2 in the partial circumferential region of the tubular body 1 are knurled by a special knurling cutter combination, and the remaining circumferential regions are not subjected to knurling. A embossing groove 7 is formed on the top of the fin 2, and at the same time as the groove 7 is formed, two first layer projections 4 are naturally formed on both sides of the fin 2 due to good plasticity of the metal material itself. Further, a second layer projecting portion 5 located only on one side of the fin 2 is formed at a lower portion of the first layer projecting portion 4. This increases the surface area of the fins in the knurled portion, while increasing the number of sharp corners, which can be thinned during the flow of the liquid film.

The heat exchange tube of the present application can increase the thickness of the liquid film adhered to the fins on the surface of the heat exchange tube when the gas refrigerant is condensed in the upper portion of the heat exchange tube by increasing the number of bosses or sharp corners on the surface of the heat exchanger tube, and also increases The heat exchange surface area is utilized, and the cold film liquid film is diluted by the characteristics of the sharp corners of the surface and the curvature of the corner of the boss, thereby enhancing the heat exchange effect. The lower portion of the heat exchange tube is a smooth fin segment 6 that has not been knurled, which can reduce the resistance of the liquid refrigerant flowing in the tank 3 and enhance the ability of the liquid refrigerant to flow downward. Based on the above design, the overall heat exchange effect of the heat exchanger tube and the shell and tube heat exchanger can be improved.

Secondly, the present application also provides a heat exchanger. Preferably, the heat exchanger is a condenser, and the condenser may be a horizontal shell and tube condenser, and the heat exchange tubes are horizontally mounted inside the condenser. After the heat exchange tubes are installed, the regions of the fins 2 with the projections are placed upwards, and the smooth fin segments 6 are placed downwards.

When the condenser is working, the heat exchange tube can pass through the fluid to be heated, and the outside of the heat exchange tube is filled with the gaseous refrigerant. During the condensation process of the heat exchange tube, on the one hand, the thickness of the liquid film adhered to the fins on the surface of the heat exchange tube when the gaseous refrigerant is condensed can be strengthened by the convex portion of the upper fin 2, and the heat exchange surface area is also increased. The corners of the surface and the corner of the boss have a large curvature, and the refrigerant liquid film is diluted. On the other hand, the ability to weaken the liquid film can be reduced by the lower smooth fin segment 6, the measures for strengthening on the fins can be reduced or eliminated, the flow resistance of the liquid refrigerant in the tank 3 can be reduced, and the ability of the liquid refrigerant to flow downward can be enhanced. The heat exchange tube in such a condenser can improve the overall heat exchange effect by taking into consideration two key aspects that affect the heat exchange efficiency.

Further, the present application also provides an air conditioner comprising the heat exchanger described in the above embodiments. Since the heat exchanger has high heat exchange efficiency, the performance of the air conditioner can also be improved.

A heat exchange tube, a heat exchanger and an air conditioner provided by the present application are described in detail above. The principles and embodiments of the present application have been described with reference to the specific embodiments herein. The description of the above embodiments is only used to help understand the method of the present application and its core idea. It should be noted that those skilled in the art can make several modifications and changes to the present application without departing from the scope of the present application. These modifications and modifications are also within the scope of the appended claims.

Claims

A heat exchange tube comprising a tube body (1), the outer wall of the tube body (1) being provided with fins (2) circumferentially on a portion of the circumferential area of the fin (2) A projection is provided, and the remaining circumferential portion of the fin (2) forms a smooth fin segment (6).
The heat exchange tube according to claim 1, characterized in that the fins (2) are spirally distributed on the outer wall of the tube body (1).
The heat exchange tube according to claim 1, wherein a region of the fin (2) on which the projection is provided forms a first continuous region in the circumferential direction, and the smooth fin segment (6) is circumferentially A second continuous region is formed.
The heat exchange tube according to claim 3, characterized in that the smooth fin section (6) corresponds to an angular range of 180° in the circumferential direction of the tubular body (1).
The heat exchange tube according to claim 1, wherein a plurality of sets of said protrusions are included in a region where said fins (2) are provided with projections, and a plurality of said plurality of said projections are arranged The circumferential spacing of the fins (2) is set.
The heat exchange tube according to claim 1, wherein the circumferential direction of the fin (2) comprises a first continuous area and a second continuous area, and the first continuous area is provided with a plurality of sets of the convex In the outlet portion, a plurality of sets of the projections are arranged along the circumferential direction of the fins (2), and the second continuous region is the smooth fin section (6).
The heat exchange tube according to claim 1, characterized in that the convex portion (6) is provided with the projection at a partial position.
The heat exchange tube according to claim 1, wherein the circumferential direction of the fin (2) includes a first continuous region and a second continuous region, the first continuous region being along the fin (2) The circumferential direction is provided with a continuous region of the convex portion, the second continuous region is the smooth fin segment (6), and the convex portion (6) is provided with the protruding portion at a partial position.
The heat exchange tube according to claim 3, 6 or 8, wherein in the state in which the heat exchange tubes are installed in the condenser, the first continuous area is disposed upward, and the second continuous area is facing Set down.
The heat exchange tube according to claim 1, wherein the free end of the projection has a sharp portion.
The heat exchange tube according to claim 1, characterized in that at least two of said projections are provided in the radial height direction of said fins (2).
The heat exchange tube according to claim 11, wherein at least two of said projections are staggered in a circumferential direction of said tubular body (1).
The heat exchange tube according to claim 11, wherein at least two of said protrusions comprise a first layer of protrusions (4) and a second layer of protrusions (5), said fins (2) a top portion is formed by knurling (7), and both ends of the pressure groove (7) extend toward the outside of the fin (2) to form the first layer protrusion (4), the second The layer projections (5) are located radially inward of the first layer projections (4), and the second layer projections (5) are formed by knurling.
The heat exchange tube according to claim 13, characterized in that each of said second layer projections (5) is located on the same side of said fins (2).
Heat exchange tube according to claim 13, characterized in that the pressure groove (7) is arranged obliquely with respect to the axis of the tube body (1).
The heat exchange tube according to claim 13, wherein said first layer projections (4) on said adjacent fins (2) are offset from each other in the circumferential direction of said tube body (1) Settings.
The heat exchange tube according to claim 13, wherein the end portion of the pressure groove (7) in the longitudinal direction thereof is triangular, trapezoidal or rectangular; and/or the second layer projection (5) The extruded surface is triangular, trapezoidal or rectangular.
The heat exchange tube according to claim 1, characterized in that the inner wall of the tube body (1) is provided with a helical projection thread (8).
Heat exchange tube according to claim 18, characterized in that the raised thread (8) is a multi-start thread.
The heat exchange tube according to claim 18, characterized in that the convex thread (8) has a trapezoidal or triangular cross section.
The heat exchange tube according to claim 1, wherein the fins (2) are integrally provided on the tube body (1), and/or the projections are integrally provided on the fins ( 2) On.
The heat exchange tube according to claim 21, wherein at least one of the fin (2) and the projection is formed by extrusion.
The heat exchange tube according to claim 4, characterized in that the angle corresponding to the smooth fin section (6) in the circumferential direction of the tubular body (1) is in the range of 1/7 to 1 in the entire circumferential direction. /2.
The heat exchange tube according to claim 1, wherein a groove body (3) is formed between adjacent fins (2), the bottom of the groove body (3) is smooth, and the bottom of the groove body (3) The intersection with the fins (2) has a smooth transition; or the bottom of the trough (3) has a smooth transition.
The heat exchange tube according to claim 2, characterized in that the angle between the fin (2) and a plane perpendicular to the axis of the tube (1) is α = 0.3° to 3.0°.
The heat exchange tube according to claim 1, wherein the fin (2) has a thickness h7 = 0.1 to 0.252 mm, and a width of the groove (3) is formed between the adjacent fins (2). H8=0.252~0.558mm.
The heat exchange tube according to claim 13, characterized in that the depth (h) of the pressure groove (7) from the top of the fin (2) is 0.1 to 0.45 mm, or the width of the pressure groove (7) H2 = 0.01 to 0.35 mm, or a length h3 of the first layer projecting portion (4) extending toward the side surface of the fin (2) = 0.05 to 0.2 mm.
The heat exchange tube according to claim 15, characterized in that the angle between the inclination direction of the pressure groove (7) and the direction in which the fins (2) extend is β = 15° to 65°.
The heat exchange tube according to claim 13, wherein a width h4 of the second layer protrusion (5) extending outward from a surface of the fin (2) is 0.05 to 0.2 mm, or a step height h5 of the bottom of the second layer projecting portion (5) and a root portion of the pipe body (1) is h5 = 0.15 to 0.45 mm, or the second layer projecting portion (5) is at the fin (2) The width in the circumferential direction is h6 = 0.05 to 0.32 mm.
The heat exchange tube according to claim 13, characterized in that the number of said pressure grooves (7) provided on said fins (2) in a single turn is n2 = 35 to 100; or in a single turn The number of the second layer projections (5) formed on the side faces of the fins (2) is n3 = 35 to 100.
The heat exchange tube according to claim 18, characterized in that the angle of inclination of the convex thread (8) with respect to the axis of the tube body (1) is α1 = 15 to 55°, or the convex thread ( 8) a convex height h9 of 0.15 to 0.55 mm on the inner wall of the tubular body (1), or an angle γ of 15 to 65° formed by the two sides of the cross section of the convex thread (8); The protruding thread (8) is a multi-start thread, and the multi-start thread is distributed n1=10-80 on the entire circumference of the inner wall of the pipe body (1).
A heat exchanger comprising the heat exchange tube according to any one of claims 1 to 31.
The heat exchanger according to claim 32, wherein said heat exchanger is a condenser.
The heat exchanger according to claim 33, wherein a region of the fin (2) on which the projection is provided is a continuous region in the circumferential direction, and the fin is mounted after the heat exchange tube (2) The area with the projections is disposed upward, and the smooth fin segments (6) are disposed downward.
An air conditioner comprising the heat exchanger according to any one of claims 32 to 34.