JP2019148375A - Heat exchanger - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a heat exchanger capable of improving heat exchange performance even when a flow velocity is relatively slow. A heat exchanger according to an embodiment of the present invention includes a plurality of heat transfer tubes and a plurality of heat transfer fins. The plurality of heat transfer tubes have a flow path through which the refrigerant flows along the first axial direction, and are arranged in the second axial direction orthogonal to the first axial direction. The plurality of heat transfer fins are arranged in the first axial direction and are joined to the plurality of heat transfer tubes. The plurality of heat transfer fins have a heat transfer portion located between the plurality of heat transfer tubes and forming a ventilation path through which a fluid passes, and the first axial direction and the second shaft provided in the heat transfer portion. Each has a louver portion including a plurality of louvers arranged in a third axial direction orthogonal to the direction. The plurality of louvers have a certain height with respect to the heat transfer portion, and the cutting angle of the plurality of louvers with respect to the heat transfer portion is from one end side to the other end side in the third axial direction. It gradually becomes smaller toward you. [Selection diagram] Fig. 3

Description

  The present invention relates to a heat exchanger that exchanges heat between a refrigerant flowing in a heat transfer tube and a fluid such as air.

  A parallel flow heat exchanger composed of a plurality of flat heat transfer tubes (flat tubes) and a plurality of heat transfer fins is known. There exist a corrugated fin and a plate-like fin in the heat-transfer fin used for this parallel flow type heat exchanger. A corrugated fin forms a strip | belt-shaped metal plate in a waveform, and is inserted between each of several heat exchanger tubes arrange | positioned up and down. The plate-like fins are band-like metal plates, which are laminated at a predetermined interval, and a heat transfer tube is inserted from one side in the width direction. These heat transfer fins are joined to the heat transfer tubes by brazing.

  Such a parallel flow type heat exchanger performs heat exchange between a fluid (for example, air) flowing between a plurality of heat transfer fins and a refrigerant flowing inside the heat transfer tube. At this time, the heat transfer fins serve to promote heat transfer between the fluid and the refrigerant. In order to improve the heat transfer performance of the heat transfer fin, it is known to cut and raise the surface of the heat transfer fin to form a louver. The heat transfer performance of the heat transfer fins can be improved by the leading edge effect and turbulent flow generated by the louver, thereby improving the heat exchange performance of the heat exchanger.

  For example, Patent Document 1 discloses a heat exchanger fin having a plurality of louvers arranged in the fluid flow direction. The plurality of louvers are cut and raised with a turning portion formed in parallel to the fluid flow direction as a boundary, and the first louver and the second louver with a smaller cut and raised angle than the first louver. The second louver is arranged adjacent to the turning portion. As a result, the flow of the fluid from the second louver on the windward side from the turning portion is reversed by the turning portion, and the fluid easily flows between the first louvers from the turning portion by the second louver on the leeward side. And it is supposed that by equalizing the distance between adjacent louvers, the fluid will flow evenly between the louvers, thereby improving the heat transfer performance of the heat transfer fins.

JP2013-195024A

  However, since the fin structure described in Patent Document 1 is premised on application to a heat exchanger for in-vehicle use, a fin structure in which the distance between louvers is the same and the louver height is different as described in Patent Document 1. When applied to a heat exchanger for refrigeration and air conditioning, there is a problem that it is difficult to obtain a desired heat exchange performance.

  In other words, in heat exchangers for refrigeration and air conditioning applications, the inflow rate of fluid is slower compared to heat exchangers for in-vehicle applications, so if louvers with different heights are mixed, the flow of fluid parallel to the fin surface is high. It is blocked by a large louver (with a large cut-and-raised angle), and a sufficient amount of fluid cannot flow between louvers with a small height (with a small cut-and-raised angle). As a result, the heat transfer performance varies between the windward side and the leeward side of the heat transfer fins, and the expected heat exchange performance cannot be improved.

  In view of the circumstances as described above, an object of the present invention is to provide a heat exchanger capable of improving the heat exchange performance even when the flow rate is relatively slow.

In order to achieve the above object, a heat exchanger according to an embodiment of the present invention includes a plurality of heat transfer tubes and a plurality of heat transfer fins.
The plurality of heat transfer tubes have a flow path through which a refrigerant flows along a first axial direction, and are arranged in a second axial direction orthogonal to the first axial direction.
The plurality of heat transfer fins are arranged in the first axial direction and joined to the plurality of heat transfer tubes.
The plurality of heat transfer fins are located between the plurality of heat transfer tubes and form a ventilation path through which a fluid passes, and the first heat transfer unit and the second axial direction provided in the heat transfer unit And a louver portion including a plurality of louvers arranged in a third axial direction orthogonal to the axial direction.
The plurality of louvers have a certain height with respect to the heat transfer section.
The cut-and-raised angle of the plurality of louvers with respect to the heat transfer portion gradually decreases from one end side in the third axial direction toward the other end side.

  The arrangement pitch of the plurality of louvers may gradually increase from the one end side toward the other end side.

  The plurality of heat transfer fins are plate fins provided in the heat transfer portion and having a plurality of tabs for adjusting an arrangement interval of the plurality of heat transfer fins, and a part of the plurality of tabs is the louver. It may be provided on the other end side in the third axial direction than the portion.

  As described above, according to the present invention, the heat exchange performance of the heat exchanger can be improved even when the flow rate is relatively slow.

It is a front view of the heat exchanger which concerns on one Embodiment of this invention. It is a fragmentary sectional view of the AA line direction in FIG. FIG. 3 is a cross-sectional view taken along line BB in FIG. 2. It is a perspective view which shows the form of the louver part in the said heat exchanger.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

FIG. 1 is a front view of a heat exchanger 100 according to an embodiment of the present invention, and FIG. 2 is a partial cross-sectional view in the AA line direction in FIG.
In each figure, the X axis (first axis), the Y axis (second axis), and the Z axis (third axis) indicate three axial directions orthogonal to each other, and the X axis direction is the left-right direction. (Width direction) and Y-axis direction correspond to the vertical direction (height direction).

[Basic configuration]
The heat exchanger of the present embodiment is a heat exchanger (condenser or evaporator) for refrigeration air conditioning use or hot water supply / hot water heating use. Hereinafter, the basic configuration of the heat exchanger 100 will be described.

The heat exchanger 100 includes a first header 11, a second header 12, a plurality of heat transfer tubes 20, and a plurality of heat transfer fins 30.
The first header 11, the second header 12, the heat transfer tubes 20, and the heat transfer fins 30 are all made of an aluminum alloy, and each joint is performed by brazing.

  Both the first header 11 and the second header 12 are formed in, for example, an elongated cylindrical shape in which both ends in the longitudinal direction (Y-axis direction) are closed. The first header 11 is disposed on one end side in the width direction of the heat exchanger 100, and the second header 12 is disposed on the other end side.

  The plurality of heat transfer tubes 20 extend linearly in the left-right direction and are arranged at intervals in the up-down direction. In the present embodiment, each heat transfer tube 20 is constituted by a flat tube having a main surface parallel to the fluid (air) flow direction (Z-axis direction) as shown in FIG. Each heat transfer tube 20 has a plurality of flow paths 21 through which the refrigerant flows. Each flow path 21 is formed independently of each other, and is formed at intervals in the fluid flow direction (Z-axis direction). One end of each heat transfer tube 20 is inserted into the first header 11, and the other end of each heat transfer tube 20 is inserted into the second header 12, and the first header 11 and the second header 12 communicate with each other via the flow path 21. .

  The plurality of heat transfer fins 30 are arranged in the left-right direction (X-axis direction) and are thermally connected to the plurality of heat transfer tubes 20. In the present embodiment, each heat transfer fin 30 is a plate-like fin that extends linearly in the vertical direction, and is formed into a shape as shown in FIG. 2 by pressing or the like. As indicated by an arrow W in FIG. 2, air as a fluid flows in the Z-axis direction. Hereinafter, the left side in FIG. 2 is also referred to as the windward side, and the right side is also referred to as the leeward side.

  Each heat transfer fin 30 is formed in a vertically long plate shape, and as shown in FIG. 2, a horizontally long notch portion 31 that extends from the leeward side end portion 302 toward the leeward side end portion 301 in the short direction is formed. A large number of heat transfer fins 30 are formed at a first interval in the longitudinal direction (Y-axis direction). When the heat transfer tubes 20 are inserted into these notches 31, the heat transfer tubes 20 are arranged at a first interval d1 in the vertical direction as shown in FIG.

  Further, as shown in FIG. 1, the heat transfer fins 30 are intervals determined in consideration of the heat exchange capability and ventilation resistance of the heat exchanger 100 in the left-right direction (X-axis direction) of the heat exchanger 100. Arranged at a second interval d2. A plurality of ventilation paths 40 surrounded by the heat transfer tubes 20 adjacent in the vertical direction and the heat transfer fins 30 adjacent in the horizontal direction are formed side by side in the vertical direction and the horizontal direction.

  The plurality of heat transfer tubes 20 and the plurality of heat transfer fins 30 are orthogonal to each other. As shown in FIG. 2, the heat transfer tubes 30 are in contact with one of the plurality of ventilation paths 40 and adjacent to each other in the vertical direction. The region located between 20 is the heat transfer section 32 that exchanges heat with the air flowing in the direction indicated by the arrow W. Further, a part of the heat transfer fin 30 that is located on the windward side end 301 side of the heat transfer fin 30 from the notch 31 is continuously formed from the upper end to the lower end of the heat transfer fin 30. A flowing water part (communication part) 33. When the heat exchanger 100 is configured as an evaporator, the flowing water portion 33 forms a flow path for allowing condensed water to flow downward vertically.

  Each heat transfer part 32 of the heat transfer fin 30 is a flat surface parallel to the YZ plane, and each heat transfer part 32 has a plurality of louvers arranged along the air flow direction (Z-axis direction). A louver portion 50 is provided. The louver part 50 promotes the heat transfer of the heat transfer fins 30 by the leading edge effect. Furthermore, the louver part 50 guides air from one ventilation path 40 adjacent to the heat transfer part 32 to the other ventilation path 40, and cuts and raises a part of the heat transfer part 32 in the X-axis direction. It is formed so as to be inclined obliquely with respect to the heat part.

  The heat transfer fin 30 further includes a plurality of tabs for adjusting the arrangement interval of the adjacent heat transfer fins 30. The plurality of tabs include a first tab 61 provided in the water flow portion 33 and a second tab 62 provided in the heat transfer portion 32, which are perpendicular to predetermined portions of the water flow portion 33 and the heat transfer portion 32. It is formed by cutting and raising in the direction (X-axis direction in FIG. 2). A plurality of the first tabs 61 and the second tabs 62 are provided at appropriate positions along the longitudinal direction of the heat transfer fin 30. In particular, the second tab 62 is provided closer to the leeward side end portion 302 side of the heat transfer fin 30 than the louver portion 50. The formation position of the 1st tab 61 is not specifically limited, In this embodiment, it is provided in the position which opposes the 2nd tab 62 in the Z-axis direction on both sides of the louver part 50.

[Louvre]
Hereinafter, details of the louver unit 50 will be described.
3 is a cross-sectional view taken along the line BB in FIG. 2, and FIG. 4 is a perspective view showing the form of the louver unit 50.

  The louver part 50 includes a plurality of slit-shaped openings 50 w that obliquely penetrate the heat transfer part 32. In the present embodiment, the louver unit 50 includes six louvers, a first louver 51, a second louver 52, a third louver 53, a fourth louver 54, a fifth louver 55, and a sixth louver 56, which are in that order. It arrange | positions toward the leeward side edge part 302 (2nd edge part) from the windward side edge part 301 (1st edge part) of the heat-transfer fin 30. FIG. Of course, the number of louvers is not limited to this, and can be arbitrarily set according to the size of the heat transfer section 32 or the like.

  The first louver 51 to the sixth louver 56 have a substantially rectangular shape having a width direction in a direction parallel to the longitudinal direction (Y-axis direction) of the heat transfer fins 30 and, as shown in FIG. The main surface 32a or the other main surface 32b is formed by cutting and raising about an axis parallel to the Y-axis direction. In the illustrated example, the first louver 51 is on the other main surface 32b side, and for the second louver 52 to the fifth louver 55, the windward side is on one main surface 32a side, the leeward side is on the other main surface 32b side, and The sixth louver 56 is cut and raised on one main surface 32a side.

  The first louver 51 to the sixth louver 56 are formed with the same width (Lw) as shown in FIG. 2 and have a constant height (H) with respect to the heat transfer section 31 as shown in FIG. It is cut and raised. The constant height means that the cut-and-raised height of each of the louvers 51 to 56 with respect to the heat transfer section 32 is substantially the same height, and is not limited to being completely the same, such as a manufacturing error. Variations may be included.

  Moreover, as shown in FIG. 3, the cut-and-raised angles of the first louver 51 to the sixth louver 56 with respect to the heat transfer section 32 are in that order (from the windward side end portion 301 side toward the leeward side end portion 302 side). The lengths of the first louver 51 to the sixth louver 56 (size in the direction orthogonal to the width direction) are gradually increased. The cut-and-raised angle of each of the louvers 51 to 56 is not particularly limited, and is appropriately set according to the required heat transfer performance.

  Furthermore, in this embodiment, the 1st louver 51-the 6th louver 56 are arrange | positioned closely. As a result, the arrangement pitches P1 to P6 of the first louver 51 to the sixth louver 56 are set so as to gradually increase in that order (from the leeward end 301 side toward the leeward end 302 side). .

[Operation of heat exchanger]
In the heat exchanger 100 of the present embodiment configured as described above, air flows from the windward side end portion 301 of the heat transfer fin 30 toward the leeward side end portion 302 by a blower fan (not shown). The air flowed by the blower fan passes through the plurality of ventilation paths 40 defined by the plurality of heat transfer tubes 20 and the heat transfer fins 30 and flows through the flow path 21 via the heat transfer portions 32 of the heat transfer fins 30. Exchanges heat with the refrigerant. Thereby, when the heat exchanger 100 is a condenser, the refrigerant | coolant which flows through the flow path 21 of the heat exchanger tube 20 is condensed, and when the heat exchanger 100 is an evaporator, the refrigerant which flows through the flow path 21 of the heat exchanger tube 20 is evaporated. .

  The flow rate of the air sent from the blower fan of the air conditioner is relatively slow compared to, for example, a heat exchanger (for example, a radiator) for use in a vehicle, and from the windward end portion 301 of the heat transfer fin 30 to the ventilation path 40. The air that has entered flows parallel to the surface of the heat transfer section 32 toward the leeward end 302. A part of the air in the ventilation path 40 flows between the first louver 51 to the sixth louver 56 as indicated by arrows in FIG. 3, and from the ventilation path 40 partitioned by one main surface 32 a of the heat transfer section 32. By being guided to the ventilation path 40 defined by the other main surface 32b, heat transfer is performed between the one main surface 32a and the other main surface 32b of the heat transfer section 32 and the air.

  According to the present embodiment, since the first louver 51 to the sixth louver 56 constituting the louver unit 50 are formed at a constant height with respect to the heat transfer unit 32, the louver cut and raised heights are different from each other conventionally. Compared to the fin structure, air can be evenly introduced between the louvers. Thereby, the heat transfer performance as the whole heat transfer part 32 improves, and as mentioned above, even when the flow rate is relatively slow, the desired heat transfer performance can be ensured.

  Furthermore, according to the present embodiment, since the cut-and-raised angle of the plurality of louvers constituting the louver unit 50 is configured to gradually decrease toward the leeward side, the air flow is reduced toward the downstream side of the louver unit 50. A flow angle becomes small (approaching the direction parallel to the surface of the heat-transfer part 32). As a result, the amount of air flowing between the downstream louvers can be increased.

  And according to this embodiment, air becomes easy to flow into the most downstream end area | region 32E (refer FIG. 3) with comparatively small heat flux at the other main surface 32b side of the heat transfer part 32 in which the louver part 50 is not provided. Therefore, the heat transfer performance in the region can be improved.

As described above, according to the present embodiment, the heat transfer performance of each heat transfer portion of the heat transfer fin 30 can be enhanced. Thereby, even when applied to a heat exchanger for refrigeration and air conditioning where the air flow rate is relatively slow, a heat exchanger having excellent heat exchange performance can be provided.
Moreover, since the stable heat transfer performance can be ensured over almost the entire region of the heat transfer section 32 by the configuration of the louver section 50 described above, the size is smaller than the conventional heat exchanger having the equivalent heat transfer performance, Thinning can be achieved.

  As mentioned above, although embodiment of this invention was described, this invention is not limited only to the above-mentioned embodiment, Of course, a various change can be added.

  For example, in the above embodiment, the case where the heat transfer fin is a plate-like fin has been described as an example. However, the present invention is not limited to this, and the present invention can also be applied when the heat transfer fin is a corrugated fin. In the above embodiment, the parallel flow type heat exchanger has been described as an example. However, the present invention is not limited to this, and the present invention is not limited to this, and is also applicable to a finned tube heat exchanger, a plate fin heat exchanger, etc. The invention is applicable.

  Further, in the above embodiment, the louvers 51 to 56 constituting the louver unit 50 are formed so that the cut-and-raised angles are different from each other. A plurality of louvers may be arranged continuously.

DESCRIPTION OF SYMBOLS 20 ... Heat-transfer tube 21 ... Flow path 30 ... Heat-transfer fin 32 ... Heat-transfer part 40 ... Ventilation path 50 ... Louver part 51-56 ... Louver 61, 62 ... Tab 100 ... Heat exchanger

Claims (3)

A plurality of heat transfer tubes having a flow path through which the refrigerant flows along the first axial direction and arranged in a second axial direction orthogonal to the first axial direction;
A plurality of heat transfer fins arranged in the first axial direction and joined to the plurality of heat transfer tubes;
The plurality of heat transfer fins are located between the plurality of heat transfer tubes and form a ventilation path through which a fluid passes, and the first heat transfer unit and the second axial direction provided in the heat transfer unit Each having a louver portion including a plurality of louvers arranged in a third axial direction orthogonal to the axial direction,
The plurality of louvers have a certain height with respect to the heat transfer section,
A heat exchanger in which the cut-and-raised angle of the plurality of louvers with respect to the heat transfer portion gradually decreases from one end side to the other end side in the third axial direction. The heat exchanger according to claim 1,
The heat exchanger in which the arrangement pitch of the plurality of louvers gradually increases from the one end side toward the other end side. The heat exchanger according to claim 1 or 2,
The plurality of heat transfer fins are configured by plate-like fins having a plurality of tabs for adjusting an arrangement interval of the plurality of heat transfer fins,
Part of the plurality of tabs is a heat exchanger provided on the other end side in the third axial direction with respect to the louver portion.

Images