JP2008215670A - Heat transfer fin, fin tube-type heat exchanger and refrigerating cycle device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a new fin and a fine tube-type heat exchanger which improving heat transfer coefficient while preventing increase of pressure loss. <P>SOLUTION: This fin 13 of the fin tube-type heat exchanger 10 is provided with elliptic hill-shaped first raised portion 14A and second raised portion 14B, and equivalent diameters of the first raised portion 14A and the second raised portion 14B are more than an outer diameter of the heat transfer tube 12 when observed from the extending direction of the heat transfer tube 12. Nearly V-shaped first cut portion 17A and second cut portion 17B are respectively formed on windward sides of the first raised portion 14A and the second raised portion 14B. A center of the heat transfer tube 12 is positioned on each of the extensions of the first cut portion 17A and the second cut portion 17B when observed from the extending direction of the heat transfer tube 12. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a heat transfer fin, a fin tube type heat exchanger, and a refrigeration cycle apparatus.

  Conventionally, various heat transfer fins have been used in, for example, air conditioners, refrigeration / refrigeration apparatuses, dehumidifiers, water heaters, etc. for home use or automobiles. In addition, fin tube heat exchangers in which heat transfer fins and heat transfer tubes are combined are often used. The fin tube type heat exchanger is composed of a plurality of heat transfer fins arranged at a predetermined fin pitch and a heat transfer tube penetrating these fins.

  In such a heat exchanger, increasing the velocity of the fluid flowing on the fin surface increases the heat transfer coefficient of the fin. However, as the velocity of the fluid flowing on the fin surface increases, the pressure loss when the fluid passes through the heat exchanger increases. Thus, in the heat exchanger, the heat transfer coefficient and the pressure loss are in a trade-off relationship. Therefore, in order to improve the performance of the heat exchanger, it is desired to improve the heat transfer rate while suppressing an increase in pressure loss.

Conventionally, the fin shape has been devised for the purpose of improving the heat transfer coefficient. For example, Patent Document 1 discloses a corrugated fin obtained by bending a plate-like fin into a wave shape. According to the corrugated fin, the heat transfer area is larger than that of the flat fin. Patent Document 2 discloses a fin tube type heat exchanger in which a large number of minute dimples are provided on the fin surface. Patent Document 2 describes that air is guided to the leeward side of the heat transfer tube by a large number of dimples on the fin, and the heat transfer coefficient is improved.
JP-A 64-90995 JP 7-239196 A

  However, the corrugated fin disclosed in Patent Document 1 has a problem of large pressure loss.

  In the fin tube type heat exchanger disclosed in Patent Document 2, since each dimple is small, in reality, it is difficult to sufficiently obtain the effect of inducing air to the lee side of the heat transfer tube, and the heat transfer performance is higher than expected. There is a problem of not improving.

  This invention is made | formed in view of this point, The place made into the objective is providing the new fin and fin tube type heat exchanger which improve a heat transfer rate, suppressing the increase in pressure loss. It is in.

  The heat transfer fin according to the present invention is a heat transfer fin in which a plurality of heat transfer tube insertion holes arranged in a predetermined row direction are formed, and a line segment connecting the centers of holes adjacent to each other in the row direction is used as a reference. A first ridge is provided on the leeward side of the reference line segment, and a leeward side of the reference line segment when a line that bisects the reference line segment is a reference vertical line. A second raised portion is provided, and a cross-sectional shape along the reference vertical line of the heat transfer fin is formed in a corrugated shape, and the first raised portion and the second raised portion are fluids on the hole side. The equivalent diameter of each raised portion when viewed from the opening direction of the hole is greater than or equal to the outer diameter of the hole.

  The finned tube heat exchanger according to the present invention includes a plurality of fins arranged at intervals and a plurality of heat transfer tubes that penetrate the fins, and a first fluid that flows on the surface side of the fins, A finned tube heat exchanger for exchanging heat with a second fluid flowing inside the heat transfer tube, wherein the heat transfer tube includes a first tube arranged in a predetermined row direction intersecting with the flow direction of the first fluid. 1 and a second heat transfer tube are included, and the heat transfer fin includes a line segment connecting the center of the first heat transfer tube and the center of the second heat transfer tube when viewed from the direction in which the heat transfer tube extends. Is a reference line segment, and a line that bisects the reference line segment is a reference vertical line, a first ridge is provided on the windward side of the reference line segment, and the leeward side of the reference line segment. A second raised portion is provided on a side of the heat transfer fin along the reference vertical line; The shape is formed in a corrugated shape, and the first and second raised portions have inclined surfaces that guide the first fluid to the first heat transfer tube side and the second heat transfer tube side. The equivalent diameter of each raised portion viewed from the extending direction of each heat transfer tube is greater than or equal to the outer diameter of each heat transfer tube.

  It is preferable that a notch is formed in the first raised portion or the second raised portion.

  It is preferable that the notch is formed on the windward side from the center of the raised portion in the flow direction of the first fluid.

  The notch is formed in a substantially V-shape that opens to the leeward or leeward side from the reference vertical line, and the notch of the first heat transfer tube is on an extension line on the first heat transfer tube side of the notch. It is preferable that the center is located and the center of the second heat transfer tube is located on an extension line of the notch portion on the second heat transfer tube side.

  It is preferable that the first raised portion and the second raised portion are formed in an elliptical hill shape.

  It is preferable that a plurality of the heat transfer fins and the heat transfer tubes are provided in a step direction intersecting with the row direction of the heat transfer tubes, and fins adjacent to each other in the step direction are shifted in the extending direction of the heat transfer tubes.

  The refrigeration cycle apparatus according to the present invention is a refrigeration cycle apparatus including a refrigerant circuit in which a compressor, a radiator, an expansion mechanism, and an evaporator are connected in order, and the evaporator is the finned tube heat exchanger. It is what is.

  ADVANTAGE OF THE INVENTION According to this invention, the new heat-transfer fin and fin tube type heat exchanger which improve a heat transfer rate can be implement | achieved, suppressing the increase in pressure loss.

<< Configuration of refrigeration cycle apparatus >>
As shown in FIG. 1, a finned tube heat exchanger 10 according to this embodiment is mounted on a refrigeration cycle apparatus 1. The refrigerant circuit of the refrigeration cycle apparatus 1 includes a compressor 2, a radiator 3, an expansion mechanism 5 including an expansion valve, and a fin tube heat exchanger 10 serving as an evaporator, which are sequentially connected in an annular shape. It is configured. The radiator 3 is installed indoors, and an indoor fan 4 is provided for the radiator 3. In addition, the radiator 3 may condense the refrigerant or may not condense the refrigerant. The finned tube heat exchanger 10 is installed outdoors. An outdoor fan 6 is disposed for the finned tube heat exchanger 10.

《Fin tube heat exchanger configuration》
As shown in FIG. 2, the fin tube type heat exchanger 10 includes a plurality of fins 13 arranged in parallel at predetermined intervals, and a plurality of heat transfer tubes 12 penetrating these fins 13. The finned tube heat exchanger 10 exchanges heat between the first fluid that flows on the surface side of the fins 13 and the second fluid that flows inside the heat transfer tubes 12. Here, the surface side of the fin 13 means the surface of the fin 13 when the outer surface of the heat transfer tube 12 is not exposed, and the fin 13 and the surface of the fin 13 when the outer surface of the heat transfer tube 12 is exposed. It refers to the surface of the heat transfer tube 12. In the present embodiment, air A flows on the surface side of the fin 13, and refrigerant flows in the heat transfer tube 12.

  The fins 13 are formed in a rectangular substantially corrugated plate shape, and are arranged along the Y direction shown in the drawing. In the present embodiment, the fins 13 are arranged at a constant fin pitch FP (see FIG. 4). The fin pitch FP is, for example, 1.0 to 3.0 mm. However, the fin pitch FP is not necessarily constant, and may be different. As shown in FIG. 4, the fin pitch FP is represented by the distance between the center positions of the two adjacent fins 13. For the fin 13, for example, a punched aluminum plate having a thickness of 0.08 to 0.2 mm can be suitably used. The surface of the fin 13 is preferably subjected to hydrophilic treatment such as boehmite treatment or application of a hydrophilic paint, or water repellency treatment.

  As shown in FIG. 2, in this embodiment, two rows of heat transfer tubes 12 are provided. The heat transfer tubes 12 in each row are arranged linearly along the longitudinal direction of the fins 13 (hereinafter simply referred to as the Z direction or the row direction). As shown in FIG. 3, when viewed from the Y direction, the first row of heat transfer tubes 12 and the second row of heat transfer tubes 12 are shifted in the Z direction by ½ of the tube pitch PP. That is, the heat transfer tubes 12 are arranged in a staggered manner. The tube pitch PP is represented by the distance between the centers of the heat transfer tubes 12 adjacent in the column direction. The outer diameter D of the heat transfer tube 12 is, for example, 1 to 20 mm. The heat transfer tube 12 is in close contact with the fin collar 13a by being expanded, and is fitted to the fin collar 13a. The heat transfer tube 12 may be a smooth tube having a smooth inner surface or a grooved tube.

  As shown in FIG. 4, the fins 13 in the first row and the fins 13 in the second row are displaced in the Y direction. Specifically, in the present embodiment, the fins 13 in the first row and the fins 13 in the second row are shifted by ½ of the fin pitch FP in the Y direction.

  The finned tube heat exchanger 10 is installed in such a posture that the flow direction (X direction) of the air A is substantially orthogonal to the stacking direction (Y direction) of the fins 13 and the row direction (Z direction) of the heat transfer tubes 12. . However, the airflow direction may be slightly inclined from the X direction as long as a sufficient amount of heat exchange can be ensured.

  Next, a detailed configuration of the fin 13 will be described. As described above, the fin 13 is formed with the fin collar 13a. A hole 12a for inserting a heat transfer tube is formed inside the fin collar 13a.

  The fins 13 are almost entirely formed in a substantially corrugated plate shape. However, the periphery of the heat transfer tube 12 in the fin 13 is formed in a flat plate shape (see FIG. 4). As shown in FIG. 3, the fin 13 includes a first raised portion 14A and a second raised portion 14B.

The first raised portion 14A is disposed on the windward side of the second raised portion 14B. In the present embodiment, the heat transfer tubes 12 that are adjacent to each other in the column direction when viewed from the direction in which the heat transfer tubes 12 extend (that is, the Y direction).
When the line segment connecting the centers C of the two is the reference line segment L1, and the line that bisects the reference line segment L1 is the reference vertical line L2, the first raised portion 14A is located on the windward side of the reference line segment L1. The second raised portion 14B is provided on the leeward side with respect to the reference line segment L1.

  14 A of 1st protruding parts and the 2nd protruding part 14B are located between the centers C of both the heat exchanger tubes 12, when it sees from a X direction. In the present embodiment, the first raised portion 14A and the second raised portion 14B are formed in an oval shape elongated in the Z direction (see a two-dot chain line in FIG. 3). Specifically, the first raised portion 14A and the second raised portion 14B are formed in an elliptical hill shape. Inclined surfaces 15 that guide air toward the heat transfer tube 12 are formed at both ends in the Z direction of the first raised portion 14A and the second raised portion 14B. In addition, the 1st protruding part 14A and the 2nd protruding part 14B should just be a protruding part which has the inclined surface which guides air toward the heat exchanger tube 12, and those shapes are not necessarily limited to elliptical hill shape. . The first raised portion 14A and the second raised portion 14B may be raised portions having other shapes such as a cone, a cone, an elliptical cone, and a quadrangular pyramid (so-called pyramid shape).

Each size of the first raised portion 14A and the second raised portion 14B when viewed from the Y direction is equal to or larger than the size of the heat transfer tube 12. That is, when viewed from the Y direction, the areas of ellipses (hereinafter simply referred to as projection plane ellipses) that serve as projection surfaces onto the fin base surfaces of the first and second raised portions 14A and 14B are respectively the heat transfer tubes 12. Is set to be equal to or greater than the area. In other words, the equivalent diameter d of the projection ellipse of the first raised portion 14A and the second raised portion 14B is equal to or larger than the outer diameter D of the heat transfer tube 12. Incidentally, when the area of the projection plane ellipse of the first raised portion 14A and the second raised portion 14B and S, is πd ^2/4 = S. In the present embodiment, the major axis of the projection plane ellipse of the first raised portion 14A and the second raised portion 14B is larger than the outer diameter D of the heat transfer tube 12, and the shorter diameter is larger than the outer diameter D of the heat transfer tube 12.

  As shown in FIG. 4, the height H from the fin base surface of the first raised portion 14A and the second raised portion 14B is smaller than the fin pitch FP. However, the value of the height H of the first raised portion 14A and the second raised portion 14B is not particularly limited, and may be, for example, 1/3 to 2/3 of the fin pitch FP, or other numerical values. Also good.

  The first raised portion 14A is formed with a first cutout portion 17A, and the second raised portion 14B is formed with a second cutout portion 17B. The windward side of the first raised portion 14A is a downward surface 18A that descends toward the windward side (see FIG. 4), and the first cutout portion 17A is formed on the downward surface 18A. Therefore, the first cutout portion 17A is formed on the windward side from the center of the first raised portion 14A. Similarly, the windward side of the second raised portion 14B is a downward surface 18B that descends toward the windward side, and the second notch portion 17B is formed on the downward surface 18B. Therefore, the second notch portion 17B is formed on the windward side from the center of the second raised portion 14B.

  As shown in FIG. 3, the first cutout portion 17A and the second cutout portion 17B are formed in a substantially V shape. Specifically, the first cutout portion 17A is formed in a substantially V shape that opens toward the leeward side, and the second cutout portion 17B is formed in a substantially V shape that opens toward the leeward side. . Further, the first cutout portion 17A is arranged so that the center C of the heat transfer tube 12 is positioned on the V-shaped extension line L3. In other words, the first cutout portion 17A extends in the radial direction of the heat transfer tube 12 located on both sides of the first cutout portion 17A. Similarly, the 2nd notch part 17B is arrange | positioned so that the center C of the heat exchanger tube 12 may be located on the V-shaped extension line L4. That is, the second notch 17B extends in the radial direction of the heat transfer tube 12 located on both sides of the second notch 17B.

《Air flow in finned tube heat exchanger》
Next, the flow of air in the finned tube heat exchanger 10 will be described.

  As shown in FIG. 5, the air A1 flowing from the front of the fin 13 first collides with the first raised portion 14A. As described above, since the first raised portion 14A is formed in an elliptical hill shape and has the inclined surface 15 that guides air to both heat transfer tubes 12, the air A1 that collides with the first raised portion 14A is The air is divided into an air A2 that passes over the first raised portion 14A and an air A3 that is guided to the heat transfer tube 12 side along the inclined surface 15 of the first raised portion 14A.

  Part of the air A2 riding on the first raised portion 14A further passes over the first cutout portion 17A, and the rest of the air A2 passes through the first cutout portion 17A and is on the back side of the fin 13. Get in. At this time, a thin temperature boundary layer is formed on the leeward side of the first cutout portion 17A by a so-called leading edge effect. Therefore, the local heat transfer coefficient on the leeward side of the first notch 17A is improved. Further, since the air A2 passes through the first cutout portion 17A from the front side of the fin 13 toward the back side, frost formation on the fin 13 can be delayed.

  On the other hand, the air A3 flowing along the inclined surface 15 of the first raised portion 14A flows in the vicinity of the heat transfer tube 12. In the vicinity of the heat transfer tube 12, the temperature difference between the fins 13 and the air is large because the temperature drop due to the heat conduction of the fins 13 is small. Therefore, heat exchange is promoted by the air A3 flowing in the vicinity of the heat transfer tube 12.

  Also in the second raised portion 14B, a part of the air A4 gets over the second raised portion 14B, and the other air A5 is guided to the heat transfer tube 12 side along the inclined surface 15 of the second raised portion 14B. The temperature boundary layer of the air A4 that gets over the second raised portion 14B becomes thinner due to the leading edge effect in the second notch portion 17B. Therefore, the local heat transfer coefficient on the leeward side of the second notch 17B is improved. Since the air A5 flowing along the inclined surface 15 is guided to the heat transfer tube 12 side having a large temperature difference from the air A5, heat exchange is promoted. In particular, since the air A5 wraps around the heat transfer tube 12, the so-called dead water area behind the heat transfer tube 12 is reduced. Therefore, the average heat transfer coefficient of the fin 13 is improved.

  In the present embodiment, the first cutout portion 17 </ b> A and the second cutout portion 17 </ b> B extend in the radial direction of the heat transfer tube 12. Therefore, a decrease in fin efficiency due to the provision of the first notch portion 17A and the second notch portion 17B is suppressed. For example, as shown in FIG. 6A, when the notch 50 intersects the radial direction of the heat transfer tube 12, the flow of the heat flow 40 that is transmitted through the fin is blocked by the notch 50. Therefore, the notch 50 becomes a thermal resistance, and the fin efficiency is lowered. On the other hand, in the present embodiment, as shown in FIG. 6B, the first notch portion 17A extends in the radial direction of the heat transfer tube 12, so that the flow of the heat flow 40 transmitted through the fin is the first cutout. It is difficult to be blocked by the notch 17A. Therefore, the first cutout portion 17A is unlikely to become a thermal resistance. Therefore, according to the present embodiment, a decrease in fin efficiency is suppressed despite the provision of the first notch 17A. The second cutout portion 17B is the same as the first cutout portion 17A.

<< Production Method of Heat Exchanger >>
Next, the manufacturing method of the said fin 13 and the fin tube type heat exchanger 10 is demonstrated. First, a raised mold corresponding to the first raised portion 14A and the second raised portion 14B described above and a mold for providing the first cutout portion 17A and the second cutout portion 17B are manufactured. Next, the molds for the first notch 17A and the second notch 17B are applied to the plate-like fins 13, and the first notch 17A and the second notch 17B are formed by press working. Then, a raised shape mold corresponding to the first raised portion 14A and the second raised portion 14B is applied to the fin 13 in which the first cutout portion 17A and the second cutout portion 17B are formed, and the first raised portion is formed by press working. 14A and the second raised portion 14B are formed. Furthermore, a hole is provided at a predetermined position through which the heat transfer tube 12 penetrates to form the fin collar 13a. Thereafter, the necessary number of fins 13 are arranged at a predetermined fin pitch, the heat transfer tubes 12 are passed through the fins 13, and the heat transfer tubes 12 and the fins 13 are expanded and joined. Thereby, the fin tube type heat exchanger 10 is obtained.

《Performance comparison simulation》
Table 1 shows a fin-tube heat exchanger equipped with conventional corrugated fins (fins in which the fins are bent into a wave shape; see, for example, FIGS. 1 and 2 of JP-A-64-90995), and the present embodiment. The simulation result which compared with the fin tube type heat exchanger of a form is shown. No. in Table 1 1 is a conventional corrugated fin, No. 1; No. 2 is a fin in which the first notch 17A and the second notch 17B are not provided in the above embodiment. 3 shows the case of the fin of the above embodiment. In this simulation, the thickness of the fin was 0.1 mm, the fin pitch was 1.49 mm, the outer diameter of the heat transfer tube was 7 mm, and the front wind speed Vair was 1 m / s. The numerical values of pressure loss in Table 1 are No. The pressure loss of 1 heat exchanger is taken as a reference (= 1), and the ratio to that is shown.

  As can be seen from Table 1, according to the finned tube heat exchanger 10 of the present embodiment, the amount of heat exchange is slightly reduced as compared with a conventional finned tube heat exchanger having corrugated fins. However, the air A flowing from the front flows so as to avoid the first raised portion 14A and the second raised portion 14B, and the increase in the orthogonal component of the mainstream air flow velocity is relatively reduced compared to the corrugated fin. Therefore, it turns out that a pressure loss falls significantly. In addition, even when the first cutout portion 17A and the second cutout portion 17B are provided, the effect of heat transfer inhibition by the first cutout portion 17A and the second cutout portion 17B is small, so that the fin efficiency does not decrease. I understand that. Furthermore, improvement in heat transfer performance is recognized due to the leading edge effect of the first notch portion 17A and the second notch portion 17B.

<< Effects of the Embodiment >>
As described above, according to the finned tube heat exchanger 10 according to the present embodiment, the first raised portion 14A is formed on the upstream side of the reference line segment L1 of the fin 13, and the leeward side of the reference line segment L1. The second raised portion 14B is formed in the shape, and the cross-sectional shape of the fin 13 along the reference vertical line L2 is formed in a waveform. Therefore, the heat transfer area of the fin 13 can be increased by the first raised portion 14A and the second raised portion 14B.

  Furthermore, in the finned tube heat exchanger 10 according to the present embodiment, the first raised portion 14A and the second raised portion 14B have an inclined surface 15 that guides air to the heat transfer tube 12 side. Therefore, air can be positively supplied to the heat transfer tube 12 side having a large temperature difference from the air. Therefore, heat transfer performance can be improved.

Moreover, according to the finned tube heat exchanger 10 according to the present embodiment, the first raised portion 14A,
Notches 17A and 17B are formed in the second raised portion 14B, respectively. Therefore, the so-called leading edge effect can improve the local heat transfer coefficient of the first raised portion 14A and the second raised portion 14B, and thus the average heat transfer rate of the fins 13 can be improved.

  In particular, in this embodiment, the notches 17A and 17B are formed on the windward side of the first raised portion 14A and the second raised portion 14B, respectively. Therefore, the leading edge effect can be enjoyed more effectively, and the average heat transfer coefficient of the fins 13 can be effectively improved.

  Further, according to the present embodiment, the notches 17A and 17B are formed in a substantially V shape, and are arranged so that the center C of the heat transfer tube 12 is positioned on the extension lines L3 and L4. . For this reason, a decrease in fin efficiency due to the notches 17A and 17B is suppressed, and high fin efficiency as a whole can be realized. Therefore, heat transfer performance can be improved.

  According to the finned tube heat exchanger 10 according to the present embodiment, the first raised portion 14A and the second raised portion 14B are formed in an elliptical hill shape. Therefore, air can be favorably guided to the heat transfer tube 12 side while expanding the heat transfer area with a relatively simple configuration. Moreover, the pressure loss of air can be suppressed low.

  Further, according to the finned tube heat exchanger 10 according to the present embodiment, the fins 13 in the first row and the fins 13 in the second row are displaced in the direction in which the heat transfer tube 12 extends. Therefore, a temperature boundary layer is formed again at the front edge of the fin 13 in the second row. Therefore, also in the fins 13 in the second row, a so-called leading edge effect can be obtained and high heat transfer performance can be exhibited.

  The finned tube heat exchanger 10 according to the present embodiment is used as an evaporator of a refrigeration cycle apparatus. Therefore, frost may be generated on the fins 13 of the fin tube type heat exchanger 10. However, in the present embodiment, the fin 13 is formed with the first raised portion 14A and the second raised portion 14B, and the air is notched 17A of the first raised portion 14A and the second raised portion 14B of the fin 13, Since it passes through 17B, it is difficult for frost to stay on the surface of the fin 13. Therefore, frost formation can be delayed and frost resistance can be improved.

<Modification>
In the above embodiment, the finned tube heat exchanger 10 is used as an outdoor heat exchanger. However, the finned tube heat exchanger 10 is not limited to an outdoor heat exchanger. Of course, it may be used as a heat exchanger. Moreover, the fin tube type heat exchanger 10 may be used not only as an evaporator but also as a radiator or the like. Further, the second fluid flowing inside the heat transfer tube is not limited to the refrigerant, and may be other fluids such as water and brine.

  As described above, the present invention relates to a heat transfer fin, a fin tube type heat exchanger including the same, and a refrigeration cycle apparatus including the heat transfer fin, for example, a heat pump system and a water heater using the same, domestic or This is useful for automobile air conditioners, refrigerators, and the like.

Configuration diagram of refrigeration cycle equipment Perspective view of finned tube heat exchanger Top view of fin IV-IV sectional view of FIG. Fin perspective view showing air flow (A) And (b) is a conceptual diagram explaining the heat flow in a fin

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Refrigeration cycle apparatus 2 Compressor 3 Radiator 5 Expansion valve (expansion mechanism)
DESCRIPTION OF SYMBOLS 10 Fin tube type heat exchanger 12 Heat transfer tube 12a Hole for heat transfer tube insertion 13 Fin (heat transfer fin)
14A 1st protruding part 14B 2nd protruding part 15 Inclined surface 17A 1st notch part 17B 2nd notch part A Air (1st fluid)
L1 Reference line segment L2 Reference vertical line L3 Extension line of the first notch L4 Extension line of the second notch

Claims (8)

A heat transfer fin in which a plurality of heat transfer tube insertion holes arranged in a predetermined row direction are formed,
When a line segment connecting the centers of the holes adjacent to each other in the column direction is a reference line segment, and a line that bisects the reference line segment vertically is a reference vertical line, the first on the windward side from the reference line segment. Is provided, and a second ridge is provided on the leeward side of the reference line segment,
The cross-sectional shape along the reference vertical line of the heat transfer fin is formed in a waveform,
The first raised portion and the second raised portion have inclined surfaces for guiding fluid to the hole side,
The heat transfer fin, wherein an equivalent diameter of each raised portion when viewed from the opening direction of the hole is equal to or larger than the outer diameter of the hole. A plurality of fins arranged at intervals from each other; a plurality of heat transfer tubes penetrating the fins; a first fluid flowing on a surface side of the fins; and a second fluid flowing inside the heat transfer tubes; A finned tube heat exchanger for exchanging heat,
The heat transfer tubes include first and second heat transfer tubes arranged in a predetermined row direction intersecting the flow direction of the first fluid,
The heat transfer fin has a reference line segment connecting the center of the first heat transfer tube and the center of the second heat transfer tube as viewed from the direction in which the heat transfer tube extends, and the reference line segment is vertical. When the bisecting line is a reference vertical line, a first ridge is provided on the leeward side of the reference line segment, and a second ridge is provided on the leeward side of the reference line segment,
The cross-sectional shape along the reference vertical line of the heat transfer fin is formed in a waveform,
The first raised portion and the second raised portion have inclined surfaces that guide the first fluid to the first heat transfer tube side and the second heat transfer tube side,
The fin tube type heat exchanger in which the equivalent diameter of each raised portion when viewed from the extending direction of each heat transfer tube is equal to or larger than the outer diameter of each heat transfer tube. The finned tube heat exchanger according to claim 2,
A finned tube heat exchanger in which a notch is formed in the first raised portion or the second raised portion. The finned tube heat exchanger according to claim 3,
The notch portion is a finned tube heat exchanger formed on the windward side from the center of the raised portion in the flow direction of the first fluid. The finned tube heat exchanger according to claim 3,
The notch is formed in a substantially V-shape opened from the reference vertical line to the leeward or leeward side,
The center of the first heat transfer tube is located on the extension line on the first heat transfer tube side of the notch,
A finned tube heat exchanger in which the center of the second heat transfer tube is located on an extension line of the cutout portion on the second heat transfer tube side. The finned tube heat exchanger according to claim 1,
The said 1st protruding part and the said 2nd protruding part are fin tube type heat exchangers formed in the elliptical hill shape. The finned tube heat exchanger according to claim 1,
A plurality of the heat transfer fins and the heat transfer tubes are provided in the step direction intersecting the row direction of the heat transfer tubes,
The fin tube type heat exchanger in which the fins adjacent to each other in the step direction are displaced in the direction in which the heat transfer tube extends. A refrigeration cycle apparatus including a refrigerant circuit in which a compressor, a radiator, an expansion mechanism, and an evaporator are connected in order,
The said evaporator is a refrigerating-cycle apparatus which is a finned tube type heat exchanger as described in any one of Claims 2-7.

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