阅读说明：本技术 热交换器和波纹翅片 (Heat exchanger and corrugated fin ) 是由 森本敬太 中村友彦 齐藤充克 下谷昌宏 西野达彦 茶谷章太 长泽聪也 于 2018-06-07 设计创作，主要内容包括：热交换器具备：多个管(20),该多个管在一个方向(DRst)上排列,供第一流体流动；以及波纹翅片(10),该波纹翅片促进第一流体与在管的相互之间流动的第二流体的热交换。该波纹翅片设置在管的相互之间,以呈波形状的方式弯曲。另外,波纹翅片具有：多个接合部(12),该多个接合部与管接合；以及多个翅片主体部(13),该多个翅片主体部将沿着波形状相邻的接合部彼此之间相连。该翅片主体部具有用于促进导热的切开立起部(14),该切开立起部呈将该翅片主体部的一部分切开立起的形状。该切开立起部具有设置在上述一个方向的至少一个端部的切开立起端部(142、143)。该切开立起端部在切开立起端部的板厚方向的至少一方具有凹凸形状(142a、143a),该凹凸形状是为了提高该切开立起端部的表面的亲水性而形成的。(The heat exchanger is provided with a plurality of tubes (20) which are arranged in directions (DRst) and through which a th fluid flows, and a corrugated fin (10) which promotes heat exchange between a th fluid and a second fluid flowing between the tubes, the corrugated fin being provided between the tubes and bent in a wave shape, the corrugated fin further comprising a plurality of joining sections (12) which are joined to the tubes, and a plurality of fin main bodies (13) which connect the joining sections adjacent to each other along the wave shape, the fin main bodies having cut-and-raised sections (14) for promoting heat conduction, the cut-and-raised sections having a shape in which a portion of the fin main body is cut and raised, the cut-and-raised sections having cut-and-raised end sections (142, 143) provided at least ends in the directions, the cut-and raised end sections having concave-convex shapes (142a, 143a) in at least directions in the plate thickness direction of the cut and raised end sections, the cut and raised concave-and convex shapes being formed in order to improve hydrophilicity of the cut and raised surfaces of the cut and raised end sections.)

A heat exchanger of the type 1, for exchanging heat between a th fluid and a second fluid, the heat exchanger comprising:

a plurality of tubes (20) arranged in directions (DRst) and through which said fluid is flowed , and

corrugated fins (10) which are disposed between the tubes, are formed so as to be bent in a wave-like manner, and promote heat exchange between the th fluid and the second fluid flowing between the tubes,

the corrugated fin has: a plurality of engaging portions (12) that engage with the pipe; and a plurality of fin body portions (13) that are connected to the joining portions adjacent to each other along the wave shape so as to connect the joining portions to each other,

the fin body has a cut-and-raised part (14) for promoting heat conduction, the cut-and-raised part has a shape in which portions of the fin body are cut and raised,

the cut-and-raised part has a cut-and-raised body part (141) for guiding the second fluid, and cut-and-raised end parts (142, 143) which are in the form of plates extending from the cut-and-raised body part and provided at least end parts in the directions in the cut-and-raised part,

the cut-and-raised end portion has a concave-convex shape (142a, 143a) formed to improve hydrophilicity of a surface of the cut-and-raised end portion at least at a position in a plate thickness direction of the cut-and-raised end portion.

2. The heat exchanger of claim 1,

the cut-and-raised end portions are provided at both ends of the cut-and-raised portion in the directions, respectively.

3. The heat exchanger according to claim 1 or 2,

the fin body has pairs of curved connecting portions (131) at both end portions of the fin body in the directions, respectively, and the pairs of curved connecting portions are connected to the joining portions,

the has, in the bending joint portion, a concave-convex shape (131a) formed to improve hydrophilicity of the surface of the bending joint portion in at least directions in the plate thickness direction of the bending joint portion.

4. The heat exchanger of claim 3,

the cut-and-raised end portions provided at least end portions in the directions include a cut-and-raised end portion (142), the cut-and-raised end portion being provided at an end portion on the side in the directions in the cut-and-raised portion,

the concavo-convex shape (142a) at the end of the cut-and-raised is formed by a plurality of grooves (142b), the concavo-convex shape of the curved connecting portion which is the portion approaching the side of the end of the cut-and-raised is also formed by a plurality of grooves (131b),

at least any side of the plurality of grooves provided in the end of the cut-and-raised is connected to at least any side of the plurality of grooves provided in the -side bent connecting portion.

5. The heat exchanger according to claim 1 or 2,

the fin body has pairs of curved connecting portions (131) at both end portions of the fin body in the directions, respectively, and the pairs of curved connecting portions are connected to the joining portions,

a cut-and-raise gap (14c) is provided in the fin body portion adjacent to the cut-and-raise portion, the cut-and-raise gap being formed by forming a shape in which the cut-and-raise portion is cut and raised,

a slit (131c) is formed in at least one side of the pair of curved connection portions, the slit having a shape cut into the curved connection portion from the slit-rise gap,

the slits reach the outside of the width (Wf) of the cut-and-raised portion in the directions.

6. The heat exchanger of any of claims 1 to 5,

the joint has a concave-convex shape (12a) on the side opposite to the side joined to the tube, and the concave-convex shape is formed to improve the hydrophilicity of the surface of the joint.

7. The heat exchanger of any of claims 1 to 5,

a tube-side convex part (16) which is constituted by the joint part of the corrugated fin and a part (161) adjacent to the joint part and which has a shape in which the side of the tube to which the joint part is joined is curved as a convex side, the tube-side convex part having a plurality of hydrophilic grooves (16a, 16b) formed for increasing the hydrophilicity of the surface of the tube-side convex part on the convex side to which the tube is joined and on the concave side which is the side opposite to the convex side,

the convex hydrophilic groove (16a) of the plurality of hydrophilic grooves has a groove depth (DPa) that is smaller than a groove depth (DPb) of the concave hydrophilic groove (16b) of the plurality of hydrophilic grooves.

8. The heat exchanger of any of claims 1 to 5,

a tube-side convex part (16) which is constituted by the joint part of the corrugated fin and a part (161) adjacent to the joint part and which has a shape in which the side of the tube to which the joint part is joined is curved as a convex side, the tube-side convex part having a plurality of hydrophilic grooves (16a, 16b) formed for increasing the hydrophilicity of the surface of the tube-side convex part on the convex side to which the tube is joined and on the concave side which is the side opposite to the convex side,

the hydrophilic groove (16a) on the convex side of the plurality of hydrophilic grooves has a groove width (WDa) that is greater than a groove width (WDb) of the hydrophilic groove (16b) on the concave side of the plurality of hydrophilic grooves.

9. The heat exchanger of any of claims 1 to 8,

the cut-and-raised body portion has a concave-convex shape (141a) formed to improve hydrophilicity of the surface of the cut-and-raised body portion at least at the position in the plate thickness direction of the cut-and-raised body portion.

10. The heat exchanger of any of claims 1 to 9,

the second fluid flows between the tubes with the side of the intersecting directions (AF) intersecting the directions as the upstream side and the other side of the intersecting directions as the downstream side,

the fin body portion has flat surfaces (15) formed along the intersecting directions,

the flat surface has a plurality of vertical grooves (15c) formed to improve the hydrophilicity of the flat surface,

the plurality of longitudinal grooves extend in the directions.

11. The heat exchanger of claim 10,

the flat surface has a plurality of transverse grooves (15b) formed to improve the hydrophilicity of the flat surface,

the plurality of transverse grooves intersect the plurality of longitudinal grooves and extend in the intersecting directions.

12. The heat exchanger of any of claims 1 to 9,

the second fluid flows between the tubes with the side of the intersecting directions (AF) intersecting the directions as the upstream side and the other side of the intersecting directions as the downstream side,

the fin body portion has flat surfaces (15) formed along the intersecting directions,

the flat surface has a plurality of transverse grooves (15b) formed to improve the hydrophilicity of the flat surface,

the plurality of transverse slots extend in the cross directions.

13. The heat exchanger of any of claims 1 to 12,

the second fluid is a gas that generates condensed water by heat exchange with the th fluid.

14. The heat exchanger of any of claims 1 to 13,

the heat exchanger is disposed in a water-contaminated environment.

15. The heat exchanger of any of claims 1 to 14,

the plurality of tubes extend in a vertical direction (DRg).

16. The heat exchanger of any of claims 1 to 15,

the depth (h) of the concave shape included in the concave-convex shape is 10 [ mu ] m or more.

17. The heat exchanger of claim 11,

the depth (h) of the grooves included in the plurality of vertical grooves is 10 [ mu ] m or more, and the depth (h) of the grooves included in the plurality of horizontal grooves is also 10 [ mu ] m or more.

18. The heat exchanger of any of claims 1 to 17,

the cut-and-raised end portion has a concave-convex shape of the cut-and-raised end portion on both sides of the cut-and-raised end portion in the plate thickness direction.

19. The heat exchanger of any of claims 1 to 18,

the cut-and-raised portion for promoting heat conduction is a louver.

20, A corrugated fin which is provided between a plurality of tubes arranged in directions (DRst) in a heat exchanger for exchanging heat between a th fluid and a second fluid, is formed so as to be curved in a wave shape, and promotes heat exchange between the th fluid flowing through the tubes and the second fluid flowing through the tubes, the corrugated fin comprising:

a plurality of engaging portions (12) that engage with the pipe; and

a plurality of fin body portions (13) that are connected to the joining portions adjacent to each other along the wave shape so as to connect the joining portions to each other,

the fin body has a cut-and-raised part (14) for promoting heat conduction, the cut-and-raised part has a shape in which portions of the fin body are cut and raised,

the cut-and-raised part has a cut-and-raised body part (141) for guiding the second fluid, and cut-and-raised end parts (142, 143) which are in the form of plates extending from the cut-and-raised body part and provided at least end parts in the directions in the cut-and-raised part,

the cut-and-raised end portion has a concave-convex shape (142a, 143a) formed to improve hydrophilicity of a surface of the cut-and-raised end portion at least at a position in a plate thickness direction of the cut-and-raised end portion.

Technical Field

The invention relates to a heat exchanger and a corrugated fin.

Background

Heat exchangers that perform heat exchange between fluids are conventionally known. For example, the heat exchanger described in patent document 1 is used. The heat exchanger of patent document 1 is a plate fin tube heat exchanger, and is configured by inserting flat tubes into cutouts formed in plate-like plate fins.

In addition, the plate fins have irregularities formed on the surfaces thereof, and the hydrophilicity of the surfaces of the plate fins is enhanced by the irregularities. This allows the condensed water to be quickly drained along the plate fins.

Disclosure of Invention

The present invention has been made in view of the above-described exemplary circumstances, and an object of the present invention is to provide types of heat exchangers and corrugated fins, which can prevent water from remaining in cut-and-raised portions (e.g., louvers) included in the corrugated fins for promoting heat transfer.

To achieve the above object, according to aspects of the present invention, a heat exchanger for exchanging heat between a th fluid and a second fluid includes a plurality of tubes arranged in directions and through which a th fluid flows, and a corrugated fin provided between the tubes and curved in a wave shape to promote heat exchange between a th fluid and the second fluid flowing between the tubes, the corrugated fin including a plurality of joining portions joined to the tubes, a plurality of fin body portions connected to the joining portions so as to connect adjacent joining portions along the wave shape to each other, the fin body portions including cut-and-raised portions for promoting heat conduction, the cut-and-raised portions having a shape in which a portion of the fin body portion is cut and raised, the cut-and-raised portion including a cut-and-raised body portion for guiding the second fluid, and a cut and raised end portion having a shape in which a plate-like body portion extending from the cut and provided in the cut-and-raised portion, the cut and raised portion including a hydrophilic surface 8678 for increasing a thickness of the cut and raised portion in the cut and raised portion in the direction, the cut and raised portion including at least 3663.

Accordingly, the surface of the cut-and-raised end portion has high hydrophilicity, so that water adhering to the cut-and-raised portion is less likely to accumulate at the cut-and-raised end portion, and the water is rapidly drained to the joint portion of the corrugated fin or the surface of the tube. Therefore, water can be prevented from remaining in the cut-and-raised portions of the corrugated fin. As a result, for example, the function of the cut-and-raised part to guide the second fluid can be prevented from being hindered by water adhering to the cut-and-raised part.

In addition, according to another aspect of the present invention, a corrugated fin provided between a plurality of tubes arranged in directions in a heat exchanger for exchanging heat between a fluid and a second fluid, the corrugated fin being formed so as to be bent in a wave shape and promoting heat exchange between a th fluid flowing in the tubes and the second fluid flowing between the tubes, the corrugated fin includes a plurality of joining portions joined to the tubes, and a plurality of fin body portions connected to the joining portions so as to connect adjacent joining portions along the wave shape, the fin body portions having cut-and-raised portions for promoting heat conduction, the cut-and-raised portions having a shape in which a portion of the fin body portion is cut and raised, the cut-and-raised portions including a cut-and-raised body portion for guiding the second fluid, and cut-and raised end portions extending from the cut and raised body portion, at least end portions provided in the cut and raised portions in directions, the cut and raised end portions having a surface with raised hydrophilicity in a direction of the cut and raised surface .

This makes it possible to achieve the same operational effects as those of the heat exchangers.

Note that reference numerals with parentheses in each component and the like denote cases of correspondence between the component and the like and specific components and the like described in the embodiments described later.

Drawings

Fig. 1 is a perspective view of a heat exchanger according to embodiment .

Fig. 2 is an enlarged perspective view of a portion of the tube and corrugated fin of the heat exchanger of fig. 1.

Fig. 3 is a perspective view of the corrugated fin of fig. 2, taken in isolation, with a portion thereof enlarged.

Fig. 4 is an IV view of fig. 2.

Fig. 5 is a schematic cross-sectional view of the corrugated fin of fig. 2 cut along a plane in the plate thickness direction, and is a view showing the groove depth of the groove formed in the surface of the corrugated fin.

Fig. 6 is a perspective view of the corrugated fin of fig. 2, which is extracted as a single body and a portion of the corrugated fin is enlarged, and the single body of the corrugated fin is viewed in the direction of the line of sight of arrow VI in fig. 4.

Fig. 7 is a perspective view partially showing a single corrugated fin of the heat exchanger in the comparative example, and showing an th state in which drainage of condensed water is retained.

Fig. 8 is a diagram corresponding to fig. 4 showing an th state in which drainage of condensed water is retained as shown in fig. 7.

Fig. 9 is a cross-sectional view showing an air flow in a case where condensed water is not present in the corrugated fin having the louver.

Fig. 10 is a cross-sectional view showing an air flow in the case where drainage of condensed water is accumulated in the corrugated fin of the comparative example as shown in fig. 7 and 8.

Fig. 11 is a perspective view partially showing a single corrugated fin included in the heat exchanger in the comparative example similar to fig. 7, and showing a second state in which drainage of condensed water is retained.

Fig. 12 is a diagram corresponding to fig. 4 showing a second state in which the drain of the condensed water is retained as shown in fig. 11.

Fig. 13 is a cross-sectional view showing an air flow in the case where drainage of condensed water is accumulated in the corrugated fin of the comparative example as shown in fig. 11 and 12.

Fig. 14 is a schematic diagram showing the film thickness and contact angle of water adhering to the surface of an object such as a corrugated fin.

Fig. 15 is a view corresponding to fig. 4, showing a phenomenon in which condensed water is discharged from the louver according to embodiment .

Fig. 16 is a view corresponding to fig. 4, showing a phenomenon in which condensed water is discharged from the bent coupling portion of the fin body to the joint portion or the tube wall surface in embodiment .

Fig. 17 is an enlarged detail view of a portion XVII of fig. 16.

Fig. 18 is a second detailed view of an enlarged XVII portion of fig. 16.

Fig. 19 is a perspective view corresponding to fig. 3, and is a view illustrating a drainage path for draining condensed water from the flat surfaces of the corrugated fins in embodiment .

Fig. 20 is a schematic diagram for explaining a drainage path of the condensed water formed on the flat surface in embodiment .

Fig. 21 is a schematic cross-sectional view of a portion of the corrugated fin of fig. 2 where the grooves are alternately arranged, the portion being cut along a plane in the plate thickness direction of the corrugated fin.

Fig. 22 is a graph showing the results of an experiment comparing deterioration of hydrophilicity with time on a grooved surface and a smooth surface.

Fig. 23 is an enlarged perspective view of a portion of a tube and a corrugated fin of a heat exchanger in the second embodiment.

Fig. 24 is a perspective view of a corrugated fin extracted as a single body and enlarged at in the third embodiment, and corresponds to fig. 3.

Fig. 25 is a diagram for explaining a drainage path of the condensed water flowing along the pipe wall surface in the third embodiment, and corresponds to fig. 4.

Fig. 26 is a perspective view of a corrugated fin extracted as a single body and enlarged at in the fourth embodiment, and corresponds to fig. 3.

Fig. 27 is a view schematically showing a joint portion and its peripheral portion in a corrugated fin in the fifth embodiment in the same direction as in fig. 4, and is a view showing the joint portion in cross section.

Fig. 28 is a schematic view illustrating a modification of the plurality of grooves provided on the surface of the corrugated fin according to each embodiment.

Fig. 29 is a view showing a heat exchanger placed horizontally as a modification of each embodiment, and corresponds to fig. 4.

Fig. 30 is a cross-sectional view schematically showing an example of a configuration in which a plurality of grooves for improving hydrophilicity of the surfaces of corrugated fins are formed only on surfaces in the plate thickness direction, which is a modification of each embodiment, and corresponds to fig. 5.

Fig. 31 is a view showing a heat exchanger having a slit fin as a modification of each embodiment, and is a perspective view of an enlarged portion of a tube and a corrugated fin of the heat exchanger.

Fig. 32 is an enlarged view showing the XXXII portion of fig. 31 in an enlarged manner.

Fig. 33 is a perspective view showing a triangular fin as a modified example of each embodiment, and is a view showing an extracted cut-and-raised portion and its periphery of the triangular fin.

Fig. 34 is a perspective view showing an offset fin as a modification of each embodiment, and simply showing a manufacturing process of the offset fin.

Detailed Description

Hereinafter, the embodiments will be described with reference to fig. in , and in the drawings, the same or equivalent parts are denoted by the same reference numerals in the following embodiments.

(embodiment )

The heat exchanger 1 of the present embodiment is used as, for example, an evaporator constituting part of a refrigeration cycle for conditioning air in a vehicle interior, the evaporator exchanges heat between a coolant, which is th fluid, circulating in the refrigeration cycle and air, which is the second fluid passing through the heat exchanger 1, and cools the air by latent heat of evaporation of the coolant, and an arrow DRg in fig. 1 indicates a vertical direction DRg of the heat exchanger 1.

As shown in fig. 1 and 2, the heat exchanger 1 includes a plurality of corrugated fins 10, a plurality of tubes 20, th to fourth header tanks 21 to 24, an outer frame member 25, a pipe connecting member 26, and the like, which are made of, for example, an aluminum alloy, and are joined to each other by brazing, and a plurality of grooves 12b to 15c are formed on the surface of the corrugated fins 10 as described later, but the grooves 12b to 15c are omitted in fig. 2 for easy visual illustration.

The plurality of tubes 20 are arranged in parallel at predetermined intervals in the tube arrangement direction DRst, and the air passing through the heat exchanger 1 flows between the plurality of tubes 20, the air flows between the tubes 20 with the side being the upstream side in the air passing direction AF and the side being the downstream side in the air passing direction AF, the air passing direction AF being crossing the tube arrangement direction DRst which is directions.

The air passing through the heat exchanger 1 is cooled by the refrigerant while flowing between the tubes 20, and condensed water is generated, in other words, the air passing through the heat exchanger 1 is a gas in which the condensed water is generated by heat exchange with the refrigerant.

The plurality of tubes 20 are arranged in 2 rows on the side and the other side in the air passage direction AF, and the plurality of tubes 20 all extend linearly in the tube extending direction DRt from the end to the other end, and the tube extending direction DRt does not necessarily correspond to the vertical direction DRg , but corresponds to the vertical direction DRg in the present embodiment, in short, the tubes 20 in the present embodiment all extend in the vertical direction DRg, that is, the vertical direction, and the air passage direction AF, the tube arranging direction DRst, and the tube extending direction DRt are directions intersecting each other, strictly speaking, directions orthogonal to each other.

The tubes 20 are inserted into the -th header tank 21 or the second header tank 22 at the upper end thereof and into the third header tank 23 or the fourth header tank 24 at the lower end thereof, and the -fourth header tanks 21-24 distribute the refrigerant to the tubes 20 and collect the refrigerant flowing from the tubes 20.

Since air flows between the plurality of tubes 20, the gap formed between the tubes 20 serves as an air passage through which air flows. The corrugated fin 10 is provided in the air passage. In other words, the corrugated fins 10 are disposed between the tubes 20. Therefore, the corrugated fin 10 of the present embodiment is an outer fin provided outside the tube 20.

The corrugated fin 10 promotes heat exchange between the refrigerant flowing inside the tubes 20 and the air flowing between the tubes 20. Specifically, the corrugated fin 10 increases the heat transfer area between the refrigerant flowing inside the tubes 20 and the air flowing outside the tubes 20, thereby improving the heat exchange efficiency between the refrigerant and the air.

The outer frame member 25 is provided further outside the portion where the plurality of tubes 20 and the plurality of corrugated fins 10 are alternately arranged in the tube arrangement direction DRst, and the pipe connecting member 26 is fixed to the side of the outer frame member 25.

The pipe connection member 26 is provided with a refrigerant inlet 27 for supplying the refrigerant and a refrigerant outlet 28 for discharging the refrigerant, and the refrigerant flowing from the refrigerant inlet 27 into the -th header tank 21 flows through the -fourth header tanks 21-24 and the plurality of tubes 20 according to a predetermined path and flows out from the refrigerant outlet 28, and at this time, the air flowing through the air passage provided with the corrugated fins 10 is cooled by latent heat of evaporation of the refrigerant flowing through the -fourth header tanks 21-24 and the plurality of tubes 20.

As shown in fig. 3 and 4, the corrugated fin 10 is formed by bending a plate-like plate member. Specifically, the corrugated fin 10 is formed by being bent so as to have a wave shape continuous in the tube extending direction DRt.

The corrugated fin 10 has a plurality of joint portions 12 and a plurality of fin body portions 13, the joint portions 12 each constitute a wave-shaped apex portion of the corrugated fin 10 and are joined to a tube wall surface 201, which is a side surface of the tube 20 facing the tube alignment direction DRst, that is, a surface 121 on the side opposite to the side joined to the tube 20, of the surfaces on both sides in the plate thickness direction of the joint portion 12 is exposed to an air passage formed between the tubes 20, the joint portion 12 and the tube 20 are joined specifically by brazing, and the joint portion 12 constitutes a wave-shaped apex portion of the corrugated fin 10 and is also referred to as a fin TOP portion.

The fin body 13 is disposed between the adjacent joint portions 12 along the wave shape of the corrugated fin 10, and is connected to each of the joint portions 12 so as to connect the joint portions 12 to each other.

The fin body 13 is R-bent at both end portions of the fin body 13 in the tube alignment direction DRst, that is, the fin body 13 has pairs of bent connecting portions 131 provided at both end portions of the fin body 13 in the tube alignment direction DRst, and a body intermediate portion 132 provided between the pairs of bent connecting portions 131, and the pairs of bent connecting portions 131 are bent and connected to the respective adjacent joint portions 12 of the fin body 13.

In fig. 3, solid lines L1, L2, L3, and L4 are virtual lines indicating boundaries between the joint 12 and the bending connecting portion 131 and between the body intermediate portion 132 and the louver 14, and do not indicate specific shapes such as grooves. This is the same in other perspective views such as fig. 2 showing the corrugated fin 10.

The fin body 13 has a plurality of louvers 14 formed by cutting and raising portions of the fin body 13, and the louvers 14 are arranged in a row in the air passage direction AF.

The louvers 14 are included in the body intermediate portion 132 of the fin body 13, and the louver 14 includes a louver body 141 including a central portion of the louver 14 in the tube alignment direction DRst, a louver end 142, and a louver other end 143 in the present embodiment, the louver end 142 and the louver other end 143 are generically referred to as louver ends 142, 143.

It should be noted that if the louver 14 is expressed as a generic concept, the louver 14 may be referred to as a cut-and-raised portion 14 for promoting heat conduction between the corrugated fin 10 and the air in contact with the corrugated fin 10, and correspondingly, the louver body portion 141 may be referred to as a cut-and-raised body portion 141, the louver end 142 may be referred to as a cut-and-raised end 142, and the louver end 143 may be referred to as a cut-and-raised end 143, and the cut-and-raised end 142 and the cut-and-raised end 143 may be referred to collectively as cut-and-raised ends 142, 143.

The louver body 141 has a flat plate shape inclined with respect to the air passage direction AF, and guides air along the louver body 141.

The end 142 of the louver is in the form of a plate extending from the louver main body 141 toward in the tube alignment direction DRst, and is provided at the end of the louver 14 on the side in the tube alignment direction DRst, and the end 142 of the louver is formed such that the plate thickness direction of the end 142 of the louver intersects with the plate thickness direction of the louver main body 141.

The end 142 of the louver is connected to the curved connecting portion 131 of the fin body 13, which is a portion around the louver 14, on the side opposite to the louver body 141 in the tube alignment direction DRst, and the curved connecting portion 131 connected to the end 142 of the louver is a curved connecting portion on the side of the tube alignment direction DRst of the pair of curved connecting portions 131 aligned with the body intermediate portion 132 therebetween at .

The louver end portion 143 has a plate shape extending from the louver body portion 141 toward the other side of the tube alignment direction DRst, and is provided at the end portion of the louver 14 on the other side of the tube alignment direction DRst, that is, in view of the arrangement of the louver end portion 142 and the louver end portion end portion 143, the louver end portions 142 and 143 are arranged to form pairs with the louver body portion 141 interposed therebetween, and are provided at both ends of the louver 14 in the tube alignment direction DRst.

The louver another end 143 is formed such that the thickness direction of the louver another end 143 intersects the thickness direction of the louver main body 141.

The louver other end 143 is connected to the curved connecting portion 131 of the fin body 13, which constitutes a portion around the louver 14, on the side opposite to the louver body 141 in the tube alignment direction DRst, and the curved connecting portion 131 connected to the louver other end 143 is a curved connecting portion on the other side of the tube alignment direction DRst of the pair of curved connecting portions 131 aligned across the body intermediate portion 132, .

As shown in fig. 2 and 3, all the louvers 14 of the fin bodies 13 are divided into four louver groups, and each louver group is constituted by a plurality of louvers 14 provided in parallel with each other with the louver bodies 141 being spaced apart by a predetermined interval.

The louvers 14 constituting the four louver groups collectively guide the air passing through the heat exchanger 1 to meander like an arrow FLf in fig. 2. In other words, air flowing as the arrows FLf snake across the louvers 14 while passing between each other. The air flows in a meandering manner, and the performance of heat exchange between the refrigerant and the air is improved.

Specifically, the body intermediate portion 132 of the fin body 13 includes a plurality of flat surfaces 15 formed along the air passage direction AF, the plurality of flat surfaces 15 being arranged in the air passage direction AF with respect to the louvers 14, that is, the plurality of flat surfaces 15 include a -side flat surface 151 provided at an -side end portion of the body intermediate portion 132 in the air passage direction AF, another -side flat surface 152 provided at an end portion on the other -side in the air passage direction AF, and an intermediate flat surface 153, and the intermediate flat surface 153 is provided between the plurality of louvers 14 included in the body intermediate portion 132.

As shown in fig. 3 and 5, the corrugated fin 10 has on its surface (more specifically, on both sides in the plate thickness direction) hydrophilic uneven shapes 12a, 131a, 141a, 142a, 143a, 15a, which are uneven shapes formed to improve the hydrophilicity of the surface. The hydrophilic uneven shapes 12a, 131a, 141a, 142a, 143a, 15a on the surface of the corrugated fin 10 are formed on the entire surface of the corrugated fin 10. The above-described uneven shape is formed to improve the hydrophilicity of the surface, and in detail, the uneven shape is formed to improve the hydrophilicity of the surface as compared with a case where the surface is a smooth surface having no uneven shape. The hydrophilic uneven shapes 12a, 131a, 141a, 142a, 143a, and 15a are sometimes simply referred to as hydrophilic uneven shapes 12a to 15 a.

The hydrophilic uneven shapes 12a to 15a on the surface of the corrugated fin 10 are formed by a plurality of grooves 12b, 131b, 141b, 142b, 143b, 15b, and 15c arranged at predetermined intervals, and the plurality of grooves 12b, 131b, 141b, 142b, 143b, 15b, and 15c are formed by a groove extending in a predetermined th direction and a groove extending in a predetermined second direction intersecting the th direction.

Therefore, the plurality of grooves 12b, 131b, 141b, 142b, 143b, 15b, and 15c constituting the hydrophilic uneven shapes 12a to 15a are concave shapes included in the hydrophilic uneven shapes 12a to 15 a. The plurality of grooves 12b, 131b, 141b, 142b, 143b, 15b, and 15c may be simply referred to as a plurality of grooves 12b to 15 c. In the drawings referred to in the present embodiment, the grooves 12b to 15c provided on the surface of the corrugated fin 10 are schematically shown in a large scale for the sake of explanation. This is the same in each of the later-described drawings showing the grooves 12b to 15 c.

Specifically, when each portion of the corrugated fin 10 is observed, the joining portion 12 has a hydrophilic uneven shape 12a formed to improve the hydrophilicity of the surface of the joining portion 12 on the side opposite to the joining side joined to the tube 20 in the plate thickness direction of the joining portion 12, and the hydrophilic uneven shape 12a is constituted by a plurality of grooves 12b formed on the surface 121 on the side opposite to the joining side of the joining portion 12.

In addition, in the corrugated fin 10 alone, the joint portion 12 has the hydrophilic uneven shape 12a on the joint side joined to the tube 20 in the plate thickness direction of the joint portion 12. However, in the heat exchanger 1, since the joint portion 12 is joined to the tube 20, the hydrophilic uneven shape 12a provided on the joining side of the joint portion 12 is almost covered with the tube 20.

The end 142 of the louver has hydrophilic irregularities 142a on both sides of the end 142 of the louver in the thickness direction, the hydrophilic irregularities being formed to improve the hydrophilicity of the surface of the end 142 of the louver , and the hydrophilic irregularities 142a are formed by a plurality of grooves 142b formed in the surface of the end 142 of the louver .

The end 143 of the louver has hydrophilic irregularities 143a on both sides of the end 143 of the louver in the thickness direction, the hydrophilic irregularities being formed to improve the hydrophilicity of the surface of the end 143 of the louver , and the hydrophilic irregularities 143a are formed by a plurality of grooves 143b formed in the surface of the end 143 of the louver .

The louver body 141 has hydrophilic uneven shapes 141a on both sides in the plate thickness direction of the louver body 141, the hydrophilic uneven shapes being uneven shapes formed to improve the hydrophilicity of the surface of the louver body 141, the hydrophilic uneven shapes 141a being formed by a plurality of grooves 141b formed on the surface of the louver body 141, and at least any of the plurality of grooves 141b provided in the louver body 141 extends in the tube alignment direction DRst.

has hydrophilic irregularities 131a on both sides of the curved connecting portion 131 in the plate thickness direction, the hydrophilic irregularities 131a being formed to improve the hydrophilicity of the surface of the curved connecting portion 131, and the hydrophilic irregularities 131a are formed by a plurality of grooves 131b formed on the surface of the curved connecting portion 131.

Each of the flat surfaces 15 of the fin body 13 has hydrophilic uneven shapes 15a formed to improve the hydrophilicity of the flat surface 15, and the hydrophilic uneven shapes 15a are formed by a plurality of grooves 15b and 15c formed in the flat surface 15, and grooves included in the plurality of grooves 15b and 15c formed to improve the hydrophilicity of the flat surface 15 intersect with each other, specifically, the plurality of grooves 15b and 15c of the flat surface 15 are formed by a plurality of -th flat surface grooves 15b and a plurality of second flat surface grooves 15 c.

In addition, since the plurality of -th flat grooves 15b are horizontal grooves extending in the air passing direction AF, the plurality of second flat grooves 15c are vertical grooves extending in the tube array direction DRst , the plurality of -th flat grooves 15b extend so as to intersect the plurality of second flat grooves 15c, that is, the same applies to any of the -side flat surface 151, the -side flat surface 152, and the intermediate flat surface 153, and the same applies to the case where the grooves included in the plurality of grooves 15b, 15c included in the flat surface 15 intersect each other as described above, except for the flat surface 15 in the corrugated fin 10.

The plurality of grooves 12b to 15c on the surface of the corrugated fin 10 are formed before the corrugated fin 10 is formed into a corrugated shape, for example. Therefore, as shown in fig. 3, the plurality of grooves 12b to 15c on the surface of the corrugated fin 10 include grooves that extend continuously over a plurality of portions 12, 131, 132, 141, 142, and 143 constituting the corrugated fin 10.

Specifically, for example, at least any of the plurality of grooves 142b of the end 142 of the louver is connected to at least any of the plurality of grooves 131b of the 0 pair of bending joints 131, which are bending joints 131 near the end 142 of the louver 1, of the bending joints 131, and this is also the same on any of both surfaces of the end 142 of the louver , and the relationship between the plurality of grooves 143b of the other end 143 of the louver and the plurality of grooves 131b of the pair of bending joints 131, which are bending joints 131 near the end 143 of the other louver , of the bending joints 131 is also the same.

More specifically, of the plurality of grooves 141b, 142b, and 143b of the louver 14, any groove that reaches a louver adjacent portion is connected to any groove of the louver adjacent portion, and the louver adjacent portion is a portion around the louver 14, that is, a portion adjacent to the louver 14, and corresponds to the louver adjacent portion with respect to the curved connecting portion 131 and the plurality of flat surfaces 15, as shown in fig. 3.

Focusing on the end 142 of the louver in the louver 14, the bending links 131 are adjacent to the end 142 of the louver , and among the plurality of grooves 142b of the end 142 of the louver , all of the grooves reaching the bending links 131 are connected to any of the grooves 131b of the bending links 131.

Similarly, focusing on the end 143 of the slat other , the other curved connecting portions 131 are adjacent to the end 143 of the slat other , and all of the grooves 143b of the end 143 of the slat other that reach the other curved connecting portions 131 are connected to any of the grooves 131b of the other curved connecting portions 131.

At least any of the plurality of grooves 142b of the end 142 of the louver is connected to at least any of the plurality of grooves 141b of the louver main body 141. along with this, at least any of the plurality of grooves 143b of the end 143 of the louver is also connected to at least any of the plurality of grooves 141b of the louver main body 141 at the end 143 of the louver .

For example, in the portion P1 in fig. 3 and the portion P2 in fig. 6, the grooves 131b of the bending connecting portions 131 and the grooves 142b of the end 142 of the louver are connected to each other, in the portion P3 in fig. 3, the grooves 141b of the louver main body portion 141 and the grooves 142b of the end 142 of the louver are connected to each other, and the two-dot chain line in fig. 6 shows a schematic shape of the corrugated fin 10.

As shown in fig. 5, the depth h of the concave shapes included in the hydrophilic uneven shapes 12a to 15a, that is, the groove depths h of the grooves 12b to 15c are, for example, 10 μm or more, and in the case of the flat surface 15 of the fin body 13, for example, the groove depths h of the -th flat surface grooves 15b are, for example, 10 μm or more, and the groove depths h of the second flat surface grooves 15c are also, for example, 10 μm or more.

This can sufficiently improve the hydrophilicity of the surface of the corrugated fin 10. If the hydrophilicity of the surface of the corrugated fin 10 is increased, the drainage of the corrugated fin 10 is improved, and the condensed water is prevented from accumulating on the surface of the corrugated fin 10. Therefore, the ventilation resistance of the air passage is prevented from becoming large due to the retention of the condensed water, and therefore the heat exchanger 1 can improve the heat exchange performance.

Next, the flow of condensed water generated by the air cooled by the refrigerant will be described. As shown in fig. 4, since the tubes 20 are arranged in the vertical direction DRg, the condensed water flows from the upper side to the lower side along the joint portions 12 of the corrugated fins 10 and the tube wall surface 201 as indicated by arrows F1 and F2, and is discharged from the lower portion of the heat exchanger 1 to the outside of the heat exchanger 1.

At this time, the fin body 13 crosses the air passage between the tubes 20, and therefore the condensed water flowing as shown by the arrow F1 passes through the surface of the end 142 of the louver and passes through the gap formed between the louvers 14, similarly, the condensed water flowing as shown by the arrow F2 passes through the surface of the end 143 of the louver and passes through the gap formed between the louvers 14, for example, in the portion a1 in fig. 4, the condensed water flowing as shown by the arrow F1 passes through the surface of the end 142 of the louver and passes over the end 142 of the louver , and in the portion a2, the condensed water flowing as shown by the arrow F2 passes through the surface of the end 143 of the louver and passes over the end 143 of the louver .

In addition, since the heat exchange between the refrigerant and the air is promoted in the louver 14, the condensed water is mainly generated in the louver 14. For example, the condensed water Wc attached to the louver body 141 of the louver 14 wets and spreads on the surface of the louver body 141 as indicated by arrows Fa and Fb.

The condensed water thus generated in the louver body 141 and the condensed water flowing from above as indicated by the arrow Fc join at the end 142 of the louver and flow toward the tube wall surface 201 or the joint 12, and the condensed water generated in the louver body 141 and the condensed water flowing from above as indicated by the arrow Fd join at the end 143 of the louver and flow toward the tube wall surface 201 or the joint 12.

From the above-described flow of the condensed water, in the corrugated fin 10, it is necessary to ensure good drainage properties toward the tube wall surface 201 and toward the joint 12 in the flow of the condensed water indicated by arrows F1 and F2.

Next, in order to explain the effects of the heat exchanger 1 of the present embodiment, a comparative example will be explained which is compared with the present embodiment. As shown in fig. 7, in the heat exchanger of this comparative example, the hydrophilic uneven shapes 12a to 15a are not provided on the surface of the corrugated fin 90. That is, the corrugated fin 90 of the comparative example is the same as the corrugated fin 10 of the present embodiment except that the surface thereof is constituted by a smooth surface having no hydrophilic uneven shapes 12a to 15 a. The components (for example, the tubes 20 and the like) other than the corrugated fin 90 of the heat exchanger of the comparative example are the same as those of the heat exchanger 1 of the present embodiment.

In the corrugated fin 90 of the comparative example shown in fig. 7 and 8, since the heat exchange performance between the air and the refrigerant is high in each louver 14, the amount of condensate generated is large, the condensate generated is guided to the end 142 of the louver or the end 143 of the louver , which forms a narrow gap, and in addition, the condensate flowing along the joint 12 or the tube wall surface 201 from above is also guided to the end 142 of the louver or the end 143 of the louver , for example, the flow of the condensate guided from above to the end 143 of the louver is indicated by an arrow Fg in fig. 8.

In the corrugated fin 90 of the comparative example, the end 142 of the louver and the end 143 of the louver have lower hydrophilicity than that of the present embodiment, and therefore, drainage from the end 142 of the louver or the end 143 of the louver to the joint portion 12 or the pipe wall surface 201 is likely to be retained, for example, if drainage from the end 143 of the louver to the joint portion 12 or the pipe wall surface 201 such as arrows Fh and Fi in fig. 8 is retained, the condensed water Wc is retained in the gap between the louvers 14, and the retained condensed water Wc spreads over the entire gap of the louvers 14 as shown by the arrow Fj, and the entire gap of the louvers 14 is blocked.

Here, if there is no condensed water Wc, for example, between the louvers 14, the air snakes along the louvers 14 as shown by an arrow FLf in fig. 9. However, when the gaps of the louvers 14 are blocked by the condensed water Wc as described above, the louvers 14 do not function, and the air flows linearly as indicated by the arrow FLn in fig. 10. Thus, if the gap between the louvers 14 is blocked by the condensed water Wc, the meandering flow of the air as indicated by the arrow FLf in fig. 9 cannot be maintained, and therefore, the cooling performance is degraded.

In the corrugated fin 90 of the comparative example, as shown in fig. 11 and 12, drainage from the joint portion 12 of the corrugated fin 90 to the tube wall surface 201 located on the lower side of the joint portion 12 is likely to be retained, for example, if drainage from the joint portion 12 to the tube wall surface 201 via the end portion 143 of the louver as shown by the arrow Fk in fig. 12 is retained, the condensate Wc is retained between the fin main bodies 13 arranged in the tube extending direction DRt, and the condensate Wc flowing from the upper side as shown by the arrow Fg and the condensate Wc. generated at the louver 14 are added to the retained condensate Wc, so the condensate Wc retained between the fin main bodies 13 spreads over the entire width of the gap between the fin main bodies 13 in the tube arrangement direction DRst as shown by the arrow Fm, and as a result, the gap between the fin main bodies 13 is blocked by the condensate Wc.

When the gaps between the fin main bodies 13 are closed by the condensed water Wc as described above, air is intercepted at the portions where the gaps between the fin main bodies 13 are closed as shown in fig. 13. In this way, if the gaps between the fin main bodies 13 are blocked by the condensed water Wc at several locations in the heat exchanger of the comparative example, the ventilation resistance through the heat exchanger increases accordingly, and the performance of the heat exchanger deteriorates.

In contrast, the heat exchanger 1 of the present embodiment is configured to prevent the condensate Wc (in other words, the drain) from staying in the heat exchanger of the comparative example described with reference to fig. 7 to 13. In the present embodiment, by preventing the condensate Wc from staying, that is, by improving the drainage of the condensate Wc, the ventilation resistance of the heat exchanger 1 can be reduced, and the performance of the heat exchanger 1 can be improved.

For example, according to the present embodiment, as shown in fig. 3, the end 142 of the louver has hydrophilic irregularities 142a formed to improve the hydrophilicity of the surface of the end 142 of the louver on both sides in the plate thickness direction of the end 142 of the louver , and the end 143 of the louver has hydrophilic irregularities 143a formed to improve the hydrophilicity of the surface of the end 143 of the louver on both sides in the plate thickness direction of the end 143 of the louver .

The surfaces of the end 142 of the louver and the end 143 of the louver have high hydrophilicity, so that the condensed water attached to the louver 14 is less likely to accumulate at the ends of the end 142 of the louver and the end 143 of the louver , and the condensed water is rapidly drained to the joint 12 of the corrugated fin 10 or the pipe wall surface 201, that is, the drainage of the end 142 of the louver and the end 143 of the louver at the portion serving as the drainage path can be promoted.

Therefore, the condensed water can be prevented from staying in the louvers 14 of the corrugated fin 10. As a result, for example, the function of the louver 14 to guide air as shown by the arrow FLf in fig. 2 and 9 can be prevented from being hindered by the condensed water adhering to the louver 14.

Further, since the groove 142b, which is a concave portion of the hydrophilic uneven shape 142a, provided in the end 142 of the louver generates a force for drawing the condensed water, the force for drawing the condensed water by the groove 142b can promote drainage of the condensed water flowing in the end 142 of the louver , which is also the same in the end 143 of the louver , it is easier to prevent the condensed water from staying in the louver 14, compared with a structure having hydrophilic uneven shapes 142a and 143a only in the side of the end 142 of the louver and the end 143 of the louver .

Further, although the hydrophilicity of the surface can be improved by providing the uneven shape on the surface of the corrugated fin 10 as described above, the effect obtained by the improvement of the hydrophilicity can be described as follows. That is, the increase in hydrophilicity of the surface can increase the spread of wetting of water adhering to the surface. As shown in fig. 14, the film thickness Tw of the water can be reduced, and the contact angle Aw of the water can be reduced. By such an action, drainage of condensed water is promoted in the heat exchanger 1 of the present embodiment.

Further, according to the present embodiment, as shown in fig. 3 and 5, the end 142 of the louver has the hydrophilic uneven shape 142a of the end 142 of the louver on both sides in the plate thickness direction of the end 142 of the louver , so that the effect of preventing the condensate water from staying in the louver 14 can be obtained by the step as compared with the case where the hydrophilic uneven shape 142a is provided only on the side in the plate thickness direction of the end 142 of the louver , which is also the same at the other end 143 of the louver.

Further, according to the present embodiment, as shown in fig. 3 and 4, the fin body 13 has pairs of curved connecting portions 131 that are connected to the joint portions 12 and are curved, respectively, at both end portions of the fin body 13 in the tube alignment direction DRst, and pairs of curved connecting portions 131 have hydrophilic concave-convex shapes 131a formed to improve hydrophilicity of the surfaces of the curved connecting portions 131, respectively, at both sides of the curved connecting portions 131 in the plate thickness direction, and therefore, by the high hydrophilicity of the surfaces of the curved connecting portions 131, drainage from the curved connecting portions 131 to the joint portions 12 or the tube wall surfaces 201 can be promoted.

Moreover, according to the present embodiment, the hydrophilic uneven shape 142a of the end 142 of the louver is formed by the plurality of grooves 142b, and is formed by the plurality of grooves 131b for the hydrophilic uneven shapes 131a of the bending connecting portions 131 on the side close to the end 142 of the louver among the bending connecting portions 131, and at least any side of the plurality of grooves 142b of the end 142 of the louver is connected to at least any side of the plurality of grooves 131b of the bending connecting portions 131.

Accordingly, the condensed water attached to the end 142 of the louver is easily pulled toward the bending joints 131, and therefore, drainage from the louver 14 can be facilitated, and therefore, drainage from the louver 14 to the joint 12 or the pipe wall surface 201 via the -side bending joint 131 can be facilitated, and drainage of the condensed water Wc flowing as shown by arrows Fn and Fo in fig. 6 and 15, for example, can be facilitated.

In addition, the same applies to the end 143 of the louver , as to the promotion of drainage from the louver 14, that is, in the present embodiment, drainage of the condensed water Wc flowing through the end 143 of the louver may be promoted as shown by arrows Fp and Fq in fig. 15, for example.

Further, according to the present embodiment, as shown in fig. 3 and 4, the joining portion 12 has the hydrophilic uneven shape 12a formed to improve the hydrophilicity of the surface of the joining portion 12 on the side opposite to the side of joined to the pipe 20, and therefore, drainage of condensed water is less likely to be accumulated in the joining portion 12, and drainage from the end 142 of the louver or the end 143 of the louver to the joining portion 12 can be promoted.

Further, the plurality of grooves 12b constituting the hydrophilic uneven shape 12a of the joint portion 12 draws the condensed water from the curved connecting portion 131 connected to the upper side of the joint portion 12. This also facilitates drainage of the condensed water Wc flowing as shown by an arrow Fr in fig. 16, for example.

In addition, in the XVII portion of fig. 16, the plurality of grooves 131b of the curved coupling portion 131 shown in fig. 3 draw the condensed water Wc on the surface. Accordingly, since the convex side of the curved shape of the curved coupling portion 131 is directed obliquely downward, the traction force due to the curved shape acts on the condensed water Wc on the curved coupling portion 131. Therefore, as shown by arrows Fs and Ft in fig. 16 and 17, drainage of the condensed water Wc flowing from the curved connecting portion 131 to the pipe wall surface 201 can be promoted.

Here, a drawing for explaining drawing of the condensed water Wc by the curved shape of the curved connecting portion 131 is shown as fig. 18. As shown in fig. 18, the radius of curvature R1 of the surface of the condensate Wc attached to the concave side of the curved shape of the curved coupling portion 131 is larger than the radius of curvature R2 of the surface of the condensate Wc attached to the convex side of the curved shape. This is because the angle θ between the convex side surface of the curved shape of the curved coupling portion 131 and the pipe wall surface 201 is an acute angle. This is because, as a physical phenomenon, when water accumulates in the corner portion, the smaller the angle formed by the two sides constituting the corner portion, the smaller the radius of curvature of the surface of the water.

Due to the magnitude relationship between the radii of curvature R1 and R2, the force drawing the condensed water Wc toward the convex side from the concave side of the curved shape of the curved coupling portion 131 is large, and drainage of the flow indicated by arrows Fs and Ft in fig. 16 and 17 is promoted.

Further, according to the present embodiment, as shown in fig. 3, the louver body 141 has the hydrophilic uneven shape 141a formed to improve the hydrophilicity of the surface of the louver body 141 on both sides in the plate thickness direction of the louver body 141, and therefore, wetting and spreading of the condensed water Wc on the surface of the louver body 141 as shown by arrows Fa and Fb in fig. 4 is promoted, and therefore, the condensed water Wc easily flows from the louver body 141 to the end portion 142 of the louver and the end portion 143 of the louver , and drainage from the louver 14 can be improved.

Further, according to the present embodiment, as shown in fig. 3, the flat surface 15 of the corrugated fin 10 has a plurality of -th flat surface grooves 15b and a plurality of second flat surface grooves 15c formed to improve the hydrophilicity of the flat surface 15, and the plurality of -th flat surface grooves 15b extend so as to intersect the plurality of second flat surface grooves 15 c.

Therefore, the condensed water Wc adhering to the flat surface 15 is drawn by the -th flat surface groove 15b and the second flat surface groove 15c, wetly spreads, and is drained to a portion around the flat surface 15. for example, as shown by arrows F1u, F2u, and F3u in fig. 19, the condensed water Wc adhering to the flat surface 15 is drained downward from the flat surface 15 through the gap between the louvers 14. at this time, the plurality of -th flat surface grooves 15b intersect the plurality of second flat surface grooves 15c, so that the number of drainage paths on the flat surface 15 increases, and drainage from the flat surface 15 can be improved.

For example, as shown in fig. 20, since the plurality of -th flat grooves 15b intersect the plurality of second flat grooves 15c, the plurality of drainage paths for the condensed water Wc on the flat surface 15 are formed as paths connecting the portion of the -th flat groove 15b and the portion of the plurality of second flat grooves 15c, and therefore, for example, both the path along the arrow F1v and the path along the arrow F2v serve as drainage paths for the condensed water Wc.

In addition, according to the present embodiment, as shown in fig. 3, the plurality of second flat grooves 15c are vertical grooves extending in the tube alignment direction DRst. Therefore, the second flat grooves 15c pull the condensate Wc adhering to the flat surfaces 15 in the tube alignment direction DRst, and therefore the condensate Wc is easily guided to the tubes 20 adjacent to the corrugated fins 10. Therefore, drainage from the flat surface 15 can be improved.

In addition, according to the present embodiment, the flat surface 15 is provided with the plurality of -th flat surface grooves 15b extending in the air passing direction AF in addition to the plurality of second flat surface grooves 15c, and therefore, the hydrophilicity of the flat surface 15 is also improved by the -th flat surface grooves 15b, and therefore, the drainage from the flat surface 15 can be improved.

In addition, according to the present embodiment, as shown in fig. 1 and 4, the plurality of tubes 20 extend in the vertical direction. Therefore, the drainage of the condensed water along the pipe wall surface 201 as shown by arrows F1 and F2 in fig. 4 can be improved by gravity.

In addition, according to the present embodiment, the depth h of the concave shape included in the hydrophilic concave-convex shapes 12a to 15a shown in fig. 5 is, for example, 10 μm or more. Thus, the hydrophilicity due to the hydrophilic uneven shapes 12a to 15a is sufficiently ensured, and the drainage effect of draining the condensed water adhering to the surface having the hydrophilic uneven shapes 12a to 15a can be sufficiently exhibited. For example, if the depth h of the concave shape is less than 10 μm, it is not easy to secure sufficient hydrophilicity necessary to obtain good water repellency.

In the present embodiment, as shown in part B1 of fig. 5 and fig. 21, in part of the corrugated fin 10, 0 surface grooves provided on surfaces in the plate thickness direction of the plurality of grooves 12B to 15c and 2 surface grooves provided on 1 surfaces are alternately arranged, and this alternate arrangement means that the 3 surface grooves and the surface grooves are alternately arranged in the direction of surfaces or surfaces along the plate thickness direction, in other words, the alternate arrangement means that surface grooves and surface grooves are arranged in the same direction, and the surface grooves do not overlap with the surface grooves in the plate thickness direction in directions.

Thus, the plurality of grooves 12b to 15c in the corrugated fin 10 are alternately arranged, and local reduction in the plate thickness of the corrugated fin 10 due to the grooves 12b to 15c being formed on the surfaces on both sides in the plate thickness direction is suppressed. Therefore, in the portion where the alternating arrangement is formed, the strength of the corrugated fin 10 can be suppressed from being reduced by the formation of the grooves 12b to 15 c. The plurality of grooves 12b to 15c may be alternately arranged, that is, the alternately arranged grooves may be included in any of the structural portions of the corrugated fin 10, such as the joint portion 12, the fin body portion 13, and the louvers 14.

As described above, in the present embodiment, the hydrophilic uneven shapes 12a to 15a are provided on the surface of the corrugated fin 10, and therefore the hydrophilicity is improved by the shape of the surface. In addition, the shape of such a surface is less subject to aging variations. Therefore, deterioration of hydrophilicity due to aging is less likely to progress, and hydrophilicity of the surface of the corrugated fin 10 can be stably exhibited.

For example, fig. 22 shows the results of an experiment in which hydrophilic irregularities 12a to 15a are formed so that the hydrophilicity is not easily deteriorated by aging. In the experiment shown in fig. 22, after hydrophilic coating was applied to the grooved surface on which the grooves corresponding to the hydrophilic uneven shapes 12a to 15a were formed and the smooth surface on which no uneven shape was formed, the degree of deterioration of hydrophilicity was measured over time. For example, the higher the hydrophilicity of a surface, the smaller the contact angle Aw (see fig. 14) of water adhering to the surface, and therefore the hydrophilicity of a grooved surface and a smooth surface can be measured by measuring the contact angle Aw of water adhering to each surface. In fig. 22, the change in hydrophilicity of the grooved surface is indicated by a solid line Lm, and the change in hydrophilicity of the smooth surface is indicated by a broken line Ln. From the results of the experiment shown in fig. 22, it can be said that the grooved surface is less likely to deteriorate due to aging than the smooth surface.

In the present embodiment, a chemical method such as hydrophilic coating is not performed on the surface of the corrugated fin 10, and this chemical method is not essential. However, if the hydrophilic uneven shapes 12a to 15a are provided and the chemical method is combined, the effect of improving hydrophilicity is further increased.

(second embodiment)

The present embodiment will be explained mainly about the differences from the th embodiment, and the same or equivalent parts as those of the above-described embodiment will be omitted or simplified.

As shown in fig. 23, the present embodiment is different from the th embodiment in the orientation of the plurality of grooves 12b to 15c provided on the surface of the corrugated fin 10, specifically, as shown in fig. 3, almost all of the grooves 12b to 15c of the th embodiment extend in the direction along the air passing direction AF or in the direction orthogonal thereto, whereas, as shown in fig. 23, almost all of the grooves 12b to 15c of the present embodiment extend in the direction inclined with respect to the air passing direction AF.

Except for the above, this embodiment is the same as the th embodiment, and in this embodiment, the effects achieved by the configuration common to the th embodiment described above can be obtained similarly to the th embodiment.

(third embodiment)

Next, a third embodiment will be described, and in this embodiment, points different from the -th embodiment will be mainly described.

As shown in fig. 24, in the present embodiment, louver gaps 14c formed between the louvers 14 arranged in the air passage direction AF are provided in the fin body 13. The louver gap 14c is a cut-and-raised gap formed by cutting and raising the louver 14, and is adjacent to the louver 14. Further, since the louver 14 has a shape extending in the tube alignment direction DRst, the louver gap 14c also has a shape extending in the tube alignment direction DRst.

Since both the corrugated fin 10 of the present embodiment and the corrugated fin 10 of the th embodiment have louvers 14, the aspect of providing the louver gaps 14c as described above is the same in both the present embodiment and the th embodiment.

However, unlike the -th embodiment, the notch 131c is formed in the pair of curved linking portions 131 of the fin body 13, and the notch 131c may be formed in at least any of the pair of curved linking portions 131, but in this embodiment, it is formed in each of the pair of curved linking portions 131.

Specifically, the slit 131c of the bending connecting portion 131 is cut into the bending connecting portion 131 from the louver gap 14c, and in the present embodiment, the slit 131c is provided so as to correspond to the louver gap 14c at the portion out of the plurality of louver gaps 14c formed in the fin body 13, and as shown in fig. 24 and 25, the slit 131c reaches a position outside the width Wf of the louver 14 in the tube alignment direction DRst.

Since the notch 131c is formed in the curved connecting portion 131 as described above, the notch portion where the notch 131c is formed is also used as a drainage path, and drainage of the area around the notch portion can be smoothly performed.

For example, as shown in fig. 25, the condensed water flows from the upper side to the lower side along the joint portions 12 of the corrugated fins 10 and the tube wall surfaces 201 as indicated by arrows F1 and F2, and is discharged from the lower portion of the heat exchanger 1 to the outside of the heat exchanger 1. At this time, if the slit 131c is not provided, the drainage path passes through the louvers 14 and follows the path of the dotted lines F1c and F2 c. In contrast, in the present embodiment, in the notch portion where the notch 131c is formed, the drainage path passes through the notch 131c and follows the path of the solid lines F1n and F2 n. Therefore, the condensed water flowing along the drainage path passing through the cut 131c smoothly flows down compared with the case without the cut 131 c. In this way, in the present embodiment, by providing the notch 131c, the condensed water flowing from the upper side can be smoothly discharged to the outside of the heat exchanger 1.

In addition to the above, the present embodiment is the same as the embodiment, and in the present embodiment, the effects achieved by the configuration common to the embodiment can be obtained as in the embodiment, and the present embodiment is a modification based on the embodiment, but the present embodiment may be combined with the second embodiment described above.

(fourth embodiment)

Next, a fourth embodiment will be described, and in this embodiment, points different from the -th embodiment will be mainly described.

As shown in fig. 26, in the present embodiment, hydrophilic uneven shapes 142a and 143a are provided only on the surface of the end 142 of the louver and the surface of the end 143 of the louver in the entire surface of the corrugated fin 10, and the portions other than the end 142 of the louver and the end 143 of the louver are smooth surfaces having no uneven shape.

The hydrophilic uneven shapes 142a and 143a of the louver end portions 142 and 143 may be formed at least times in the plate thickness direction of the louver end portions 142 and 143, but in the present embodiment, they are formed on both sides of the louver end portions 142 and 143 in the plate thickness direction.

In addition to the above, the present embodiment is the same as the embodiment, and in the present embodiment, the effects achieved by the configuration common to the embodiment described above can be obtained as in the embodiment, and the present embodiment is a modification based on the embodiment, but the present embodiment may be combined with the second embodiment or the third embodiment described above.

(fifth embodiment)

Next, a fifth embodiment will be described, and in this embodiment, points different from the embodiment will be mainly described.

In the present embodiment, as shown in fig. 27, the corrugated fin 10 has a tube side convex portion 16 composed of a joint portion 12 in the corrugated fin and a joint abutting portion 161 adjacent to the joint portion 12, the tube side convex portion 16 has a shape in which the side of a tube 20 (see fig. 4) to which the joint portion 12 included in the tube side convex portion 16 is joined is curved as a convex side, and the tube side convex portion 16 includes the joint portion 12, so the corrugated fin 10 has the same number of tube side convex portions 16 as the number of joint portions 12.

The joint adjacent portion 161 is formed into pairs with the joint 12 therebetween, and is extended from both ends of the joint 12, the joint adjacent portion 161 is included in the bending connecting portion 131, and for example, the joint adjacent portion 161 may be portion of the bending connecting portion 131, or may be all of the portions.

The tube-side convex portion 16 has a plurality of hydrophilic grooves 16a, 16b formed to improve the hydrophilicity of the surface of the tube-side convex portion 16 on the convex side to be joined to the tube 20 and on the concave side opposite to the convex side, respectively. That is, the tube-side convex portion 16 has a plurality of hydrophilic grooves 16a provided on the convex side and a plurality of hydrophilic grooves 16b provided on the concave side. Since the tube-side convex portion 16 includes the joint portion 12, the hydrophilic grooves 16a and 16b of the tube-side convex portion 16 include the groove 12b of the joint portion 12 (see fig. 3). The convex side of the tube-side convex portion 16 is also referred to as a peak side, and the concave side of the tube-side convex portion 16 is also referred to as a valley side.

The convex hydrophilic groove 16a and the concave hydrophilic groove 16b of the tube-side convex portion 16 are formed to have different shapes. Specifically, the groove depth DPa of the hydrophilic groove 16a on the convex side is smaller than the groove depth DPb of the hydrophilic groove 16b on the concave side. The groove width WDa of the hydrophilic groove 16a on the convex side may be larger than the groove width WDb of the hydrophilic groove 16b on the concave side.

The above-described relationship in size of the groove depths DPa and DPb, such as "DPa < DPb", may be established for the entire pipe-side convex portion 16, or may be established only for the portion in the pipe-side convex portion 16, and the above-described relationship in size of the groove widths WDa and WDb, such as "WDa > WDb", may be established for the entire pipe-side convex portion 16, or may be established only for the portion in the pipe-side convex portion 16.

The relationship between the groove depths DPa and DPb and the relationship between the groove widths WDa and WDb in the tube-side convex portions 16 may or may not be located in the corrugated fin 10 other than the tube-side convex portions 16.

Except for the above, this embodiment is the same as the th embodiment, and in this embodiment, the effects achieved by the configuration common to the th embodiment described above can be obtained similarly to the th embodiment.

In addition, according to the present embodiment, the groove depth DPa of the convex hydrophilic groove 16a of the plurality of hydrophilic grooves 16a and 16b of the tube-side convex portion 16 is smaller than the groove depth DPb of the concave hydrophilic groove 16b of the plurality of hydrophilic grooves 16a and 16 b.

Therefore, the capillary force generated by the hydrophilic grooves 16a, 16b of the tube-side convex portion 16 is "convex side < concave side", and therefore water is easily collected on the surface of the concave side of the tube-side convex portion 16 serving as a drainage path. As a result, smooth water drainage from the heat exchanger 1 is facilitated. In addition, the unevenness can be reduced in the surface of the tube-side convex portion 16 on the convex side to be joined to the tube 20, and the corrugated fin 10 can be reliably joined to the tube 20.

In the tube-side convex portion 16, the groove width WDa of the hydrophilic groove 16a on the convex side is larger than the groove width WDb of the hydrophilic groove 16b on the concave side. This also facilitates water collection on the concave surface of the tube-side convex portion 16 as described above, and the corrugated fin 10 can be reliably joined to the tube 20.

Further, although this embodiment is a modification example based on the th embodiment, this embodiment may be combined with the second embodiment or the third embodiment described above.

(other embodiments)

(1) In each of the above embodiments, as shown in fig. 5, the groove depth h of the plurality of grooves 12b to 15c formed on the surface of the corrugated fin 10 is, for example, 10 μm or more, preferably 10 μm or more. However, the groove depth h is not necessarily 10 μm or more.

(2) In each of the above embodiments, the grooves 12b to 15c on the surface of the corrugated fin 10 all extend linearly as shown in fig. 3, for example, but the present invention is not limited thereto, and may be curved, for example.

The grooves 12b to 15c may be uniform in groove width or non-uniform. The grooves 12b to 15c may be grooves having a uniform groove depth or may be non-uniform grooves.

(3) In the above-described embodiments, as shown in fig. 3 and 23, the plurality of grooves 12b to 15c provided on the surface of the corrugated fin 10 extend continuously from the end portion to the end portion of the surface, but this is examples, and as shown in fig. 28, for example, the plurality of grooves 12b to 15c may be intermittently disconnected.

(4) In each of the above embodiments, the heat exchanger 1 is arranged such that the tubes 20 extend in the vertical direction DRg as shown in fig. 1 and 4, but is not limited to the arrangement direction of the heat exchanger 1. For example, as shown in fig. 29, the heat exchanger 1 may be configured such that the tubes 20 are in a direction extending in the horizontal direction.

In the case where the heat exchanger 1 is disposed as shown in fig. 29, the condensed water Wc flows as indicated by an arrow Fw in the drain from the louvers 14 to the joint portion 12 or the pipe wall surface 201, for example, and therefore, the same drainage effect as in the above-described and second embodiment can be obtained in the drain from the louvers 14 to the joint portion 12 or the pipe wall surface 201, that is, in the heat exchanger 1 of fig. 29, the drain from the louvers 14 can be promoted, and if the drain from the louvers 14 is promoted, the performance degradation of the heat exchanger 1 can be suppressed as in the above-described and second embodiment, and the increase in the draft resistance of the heat exchanger 1 can be suppressed by the decrease in the water film thickness of the louvers 14.

(5) In the above embodiments, the case where the heat exchanger 1 is used as an evaporator has been described, but the present invention is not limited thereto. The heat exchanger 1 of each embodiment may be a heat exchanger other than the evaporator as long as it is configured to require water discharge.

For example, the heat exchanger 1 may be a heat exchanger disposed in a wet environment, instead of an evaporator. Specifically, a condenser and a radiator for an air conditioner provided in an engine room of a vehicle may be covered with water during traveling of the vehicle, and thus correspond to a heat exchanger provided in a wet environment.

(6) In the above embodiments, the th fluid flowing through the tubes 20 is a refrigerant, but the th fluid may be assumed to be a fluid other than a refrigerant.

(7) In the -th embodiment, as shown in fig. 3 and 5, for example, the hydrophilic uneven shapes 12a to 15a on the surface of the corrugated fin 10 are formed over the entire surface of the corrugated fin 10, but it is also conceivable that the hydrophilic uneven shapes are formed locally on the surface.

For example, it is also conceivable that the hydrophilic uneven shapes 12a to 15a are not formed on both surfaces in the plate thickness direction of the corrugated fin 10, but formed only on surfaces in the plate thickness direction, that is, the louver end portions 142 and 143 may have the hydrophilic uneven shapes 142a and 143a in at least of the plate thickness direction of the louver end portions 142 and 143, respectively, the bending connection portion 131 may have the hydrophilic uneven shape 131a in at least of the plate thickness direction of the bending connection portion 131, and the louver main body portion 141 may have the hydrophilic uneven shape 141a in at least of the plate thickness direction of the louver main body portion 141.

For example, in a structure in which the hydrophilic uneven shapes 12a to 15a are formed only on surfaces in the plate thickness direction of the corrugated fin 10, the hydrophilic uneven shapes 12a to 15a can be formed as shown in fig. 30, and in fig. 30, the groove depth h of the plurality of grooves 12b to 15c constituting the hydrophilic uneven shapes 12a to 15a is 1/2 or more of the plate thickness of the portion where the grooves 12b to 15c are formed.

From another point of view, it is also conceivable that the hydrophilic uneven shapes 12a to 15a are formed only at specific locations in the corrugated fin 10. for example, the hydrophilic uneven shapes 12a to 15a may be provided only at the end portion 142 of the louver and the end portion of the louver in the corrugated fin 10, and not at other locations.

That is, as shown in fig. 26, the fourth embodiment in which the hydrophilic uneven shapes 142a, 143a are provided on both the louver ends 142, 143 is example, and the hydrophilic uneven shapes 142a, 143a may be provided only on the side of the louver ends 142, 143, in short, the louver ends 142, 143 provided on at least ends in the tube alignment direction DRst in the louver 14 may have the hydrophilic uneven shapes 142a, 143a, in other words, at least the side of the end 142 of the louver and the end 143 of the louver may have the hydrophilic uneven shapes 142a, 143 a.

(8) In the th embodiment, as shown in fig. 5B 1 and fig. 21, of the plurality of grooves 12B to 15c of the corrugated fin 10, the portion of the corrugated fin 10 is configured such that surface grooves and surface grooves are alternately arranged, but this is example, and for example, surface grooves and surface grooves may be alternately arranged on the entire corrugated fin 10.

(9) In the third embodiment described above, as shown in fig. 24, the slit 131c of the bending connection portion 131 is provided so as to correspond to the louver gap 14c at the portion out of the plurality of louver gaps 14c formed in the fin body 13, but this is example, and the slit 131c may be provided for each of the plurality of louver gaps 14c formed in the fin body 13 so as to correspond to all of the plurality of louver gaps 14 c.

(10) In the fifth embodiment described above, as shown in fig. 27, the plurality of hydrophilic grooves 16a, 16b of the tube-side convex portion 16 have both the magnitude relationship of the groove depths DPa, DPb such as "DPa < DPb" and the magnitude relationship of the groove widths WDa, WDb such as "WDa > WDb".

(11) In each of the above embodiments, the corrugated fin 10 has louvers as the cut-and-raised portions 14 for promoting heat conduction, for example, as shown in fig. 3, but the cut-and-raised portions 14 may be members other than the louvers, for example, as shown in fig. 31 to 34.

Specifically, fig. 31 and 32 show a slit fin in which the cut-and-raised portion 14 forms a slit. In the slit fin, for example, hydrophilic uneven shapes 142a and 143a are formed at the cut-and-raised end portions 142 and 143. That is, hydrophilic convexo- concave shapes 142a and 143a are formed in the portions C1 and C2 in fig. 32.

Fig. 33 shows a triangular fin in which the cut-and-raised portion 14 forms a triangular vent hole. The triangular fins are also formed with hydrophilic uneven shapes 142a, 143a, as in the slit fins described above. In fig. 33, the cut-and-raised portion 14 and its periphery are shown in an extracted manner, and the wave shape of the corrugated fin 10 is not shown.

Fig. 34 shows an offset fin in which a wave-shaped portion is offset and a cut-and-raised portion 14 is formed, and in this offset fin, as shown in fig. 34 (C), a hydrophilic uneven shape 142a is formed at an end 142 of a cut-and-raised , that is, a hydrophilic uneven shape 142a is formed at a C3 portion shown in fig. 34 (C), and fig. 34 (C) shows a finished offset fin, and the whole of fig. 34 (a), (b), and (C) shows a manufacturing process of the offset fin, that is, as shown in fig. 34 (a), a wave-shaped fin material is first prepared, and then, as shown in fig. 34 (b), a portion 14d of the fin material, which is a cut-and-raised portion 14 with a dot hatching, is offset from other portions, and as a result, the offset fin shown in fig. 34 (C) is obtained.

Specifically, the slit fins of fig. 31 and 32, the triangular fins of fig. 33, and the offset fins of fig. 34 described above are all in a wave shape, and are types of the corrugated fins 10, and in each of the corrugated fins 10 of fig. 31 to 34, the hydrophilic uneven shapes 12a to 15a may be formed not only on the cut-and-raised end portions 142 and 143 but also on the entire surface of the corrugated fin 10.

(12) The present invention is not limited to the above-described embodiments, and can be implemented in various modifications. The above embodiments are not irrelevant to each other, and can be appropriately combined unless it is clear that the combination is not possible. In the above embodiments, it goes without saying that elements constituting the embodiments are not essential except for cases where the elements are specifically indicated to be essential and cases where the elements are clearly considered to be essential in principle.

In the above embodiments, when the numbers of the components of the embodiments, such as the number, the numerical value, the number, and the range, are referred to, the numbers are not limited to the specific numbers except for the case where the numbers are specifically indicated to be necessary and the case where the numbers are clearly limited to the specific numbers in principle. In the above embodiments, when referring to the material, shape, positional relationship, and the like of the constituent elements and the like, the material, shape, positional relationship, and the like are not limited to those unless otherwise specified or limited to a specific material, shape, positional relationship, and the like in principle.

(conclusion)

According to the th viewpoint shown in part or whole of of each of the above embodiments, a plurality of tubes through which the th fluid flows are arranged in directions, the cut-and-raised portion of the corrugated fin has a cut-and-raised end portion which is formed in a plate shape extending from the cut-and-raised body portion and which guides the second fluid, and at least end portions of the cut-and-raised portion in the directions are provided, and the cut-and-raised end portion has a concave-convex shape formed to improve hydrophilicity of a surface of the cut-and-raised end portion in at least directions in a plate thickness direction of the cut-and-raised end portion.

Further, according to the second aspect, the cut-and-raised end portions are provided at both ends in the directions in the cut-and-raised portion, respectively, and the cut-and-raised end portions have the concave-convex shape in at least the direction in the plate thickness direction of the cut-and-raised end portions as described above, and therefore, at both ends of the cut-and-raised portion, water adhering to the cut-and-raised portion is less likely to be retained due to the improved hydrophilicity of the surface, and therefore, it is easier to prevent water from being retained in the cut-and-raised portion of the corrugated fin, as compared with the configuration according to the aspect.

Further, according to the third aspect, the fin body portion has pairs of curved coupling portions which are coupled to the joint portions and curved, respectively, at both end portions of the fin body portion in the directions, and pairs of curved coupling portions have a concave-convex shape formed for improving hydrophilicity of the surface of the curved coupling portions at least at sides in the plate thickness direction of the curved coupling portions.

From a fourth aspect, the cut-and-raised end provided at least ends in the directions includes a cut-and-raised end, and the cut-and-raised end is provided at the side end in the directions in the cut-and-raised portion, the concavo-convex shape of the end is formed by a plurality of grooves, and 5 is formed by a plurality of grooves for connecting the concavo-convex shape of the curved connecting portion in the direction close to the end of the cut-and-raised end in the curved connecting portion, and at least any one of the plurality of grooves provided in the cut-and-raised end and at least any one of the plurality of grooves provided in the curved connecting portion in the direction are easily pulled toward the curved connecting portions, whereby water attached to the cut-and-raised end can be easily pulled toward the curved connecting portions, and drainage from the cut-and-raised portion to the joining portion or the wall surface of the pipe can be promoted.

Further, according to the fifth aspect, the fin body portion has pairs of curved coupling portions which are coupled to the joint portions and curved at both end portions of the -direction fin body portions, respectively, and a cut-and-raised gap is provided in the fin body portion adjacent to the cut-and-raised portion, the cut-and-raised gap being formed in a shape in which the cut-and-raised portion is cut and raised, and a notch is formed in in at least any one of the pairs of the curved coupling portions, the notch being in a shape cut from the cut-and-raised gap with respect to the curved coupling portion, the notch reaching outside the width of the -direction cut-and-raised portions.

Further, according to the sixth aspect, the joint portion has the uneven shape formed to improve the hydrophilicity of the surface of the joint portion on the side opposite to the side where the pipe is joined, and therefore, drainage is less likely to be retained in the joint portion, and drainage from the cut-and-raised portion to the joint portion can be promoted.

In addition, according to a seventh aspect, a tube side convex part is provided which is constituted by a joining part in the corrugated fin and a part adjacent to the joining part and has a shape in which the side of the tube to which the joining part is joined is curved as a convex side, the tube side convex part has a plurality of hydrophilic grooves on the convex side to be joined to the tube and a concave side which is the opposite side to the convex side, respectively, and the plurality of hydrophilic grooves are formed to increase the hydrophilicity of the surface of the tube side convex part, and the groove depth of the hydrophilic groove on the convex side of the plurality of hydrophilic grooves is smaller than the groove depth of the hydrophilic groove on the concave side of the plurality of hydrophilic grooves.

Therefore, the capillary force generated by the hydrophilic groove of the tube-side convex part is "convex side < concave side", and therefore water is easily collected on the surface of the concave side of the tube-side convex part serving as a drainage path. As a result, smooth water drainage from the heat exchanger is facilitated. In addition, the unevenness can be reduced in the surface of the tube-side convex portion on the convex side to be engaged with the tube, and the corrugated fin can be reliably engaged with the tube.

In addition, according to an eighth aspect, a tube-side convex part is provided which is constituted by a joining part of the corrugated fin and a part adjacent to the joining part and has a shape in which the side of the tube to which the joining part is joined is curved as a convex side, the tube-side convex part has a plurality of hydrophilic grooves on the convex side to be joined to the tube and a concave side on the opposite side to the convex side, respectively, the plurality of hydrophilic grooves being formed to increase the hydrophilicity of the surface of the tube-side convex part, and the groove width of the hydrophilic groove on the convex side of the plurality of hydrophilic grooves is larger than the groove width of the hydrophilic groove on the concave side of the plurality of hydrophilic grooves.

Therefore, as in the seventh aspect, water is easily collected on the concave surface of the tube-side convex portion, and the corrugated fin can be reliably joined to the tube.

In addition, according to the ninth aspect, the cut-and-raised main body portion has the uneven shape formed to improve the hydrophilicity of the surface of the cut-and-raised main body portion at least sides in the plate thickness direction of the cut-and-raised main body portion.

Further, according to a tenth aspect, the second fluid flows between the tubes with the side of the intersecting directions intersecting the directions as the upstream side and the side of the intersecting directions as the downstream side, the fin body has a flat surface formed along the intersecting directions, the flat surface has a plurality of vertical grooves formed to improve the hydrophilicity of the flat surface, and the plurality of vertical grooves extend in the directions, and therefore, the vertical grooves pull water adhering to the flat surface in the directions, and therefore, the water is easily guided to the tubes adjacent to the corrugated fins, and therefore, the drainage from the flat surface can be improved.

Further, according to the tenth aspect, the flat surface has a plurality of lateral grooves formed to improve the hydrophilicity of the flat surface, the lateral grooves intersecting the longitudinal grooves and extending in the aforementioned intersecting directions, and therefore, water adhering to the flat surface is drawn by the longitudinal grooves and the lateral grooves, wets and spreads, and drains to a portion around the flat surface.

In addition, according to the twelfth aspect, the flat surface has a plurality of lateral grooves formed to improve the hydrophilicity of the flat surface, and the plurality of lateral grooves extend in the intersecting directions.

In addition, according to the thirteenth aspect, the second fluid is a gas in which condensed water is generated by heat exchange with the th fluid.

In addition, according to a fourteenth aspect, the heat exchanger is installed in a wet environment.

In addition, according to a fifteenth aspect, the plurality of tubes extend in the vertical direction. Therefore, the drainage of water along the pipe wall surface can be improved by gravity.

In a sixteenth aspect, the concave-convex shape includes a concave shape having a depth of 10 μm or more. This can sufficiently ensure hydrophilicity due to the above-described uneven shape, and sufficiently exhibit a drainage effect of draining water adhering to the surface having the uneven shape.

In addition, according to the seventeenth aspect, the depth of the groove included in the plurality of vertical grooves is 10 μm or more, and the depth of the groove included in the plurality of horizontal grooves is also 10 μm or more. Thus, hydrophilicity due to the vertical grooves and the horizontal grooves can be sufficiently ensured, and a drainage effect of draining water adhering to the flat surface can be sufficiently exhibited.

Further, according to the eighteenth aspect, the cut-and-raised end portion has the uneven shape of the cut-and-raised end portion on both sides in the plate thickness direction of the cut-and-raised end portion, and therefore, compared with the case where the uneven shape is provided only on the side in the plate thickness direction of the cut-and-raised end portion, the effect of preventing water from staying in the cut-and-raised portion of the corrugated fin can be obtained by the step .

In addition, according to a nineteenth aspect, the cut-and-raised portion for promoting heat conduction is a louver.

In addition, according to a twentieth aspect, the cut-and-raised portion of the corrugated fin has a cut-and-raised end portion having a plate shape extending from the cut-and-raised body portion and at least end portions in the directions provided in the cut-and-raised portion, and the cut-and-raised end portion has a concave-convex shape formed to improve hydrophilicity of a surface of the cut-and-raised end portion in at least directions of a plate thickness direction of the cut-and-raised end portion, and the cut-and-raised portion guides the second fluid.