JP2008170035A - Fin tube-type heat exchanger, fin for heat exchanger, and heat pump device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a fin tube-type heat exchanger having small pressure loss though it has superior heat transferring performance. <P>SOLUTION: This fin tube-type heat exchanger 1 has a plurality of fins 3a, 3b and a plurality of heat transfer tubes 2a, 2b penetrating through the plurality of fins. The fins 3a, 3b respectively include fin base portions 3 having through holes 7k, 7j, and raised portions 5a, 5b projecting from the fin base portions 3, and are connected by a connecting portion. Cuts 9a, 9b penetrating through the fins 3a, 3b are formed along the boundary of upstream parts 6a, 6b of the raised portions 5a, 5b and the fin base portions 3. Clearances 8a, 8b based on the cuts 9a, 9b are formed between the upstream parts 6a, 6b of the raised portions 5a, 5b and the fin base portions 3, and the air A can be circulated from a first main surface 4p side to a second main surface 4q side of the fins 3a, 3b through the clearances 8a, 8b. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a finned tube heat exchanger, a heat exchanger fin, and a heat pump device.

  Conventionally, fin tube heat exchangers have been used in home or automobile air conditioners, refrigerators / refrigerators, dehumidifiers, water heaters, and the like. 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, fins that have been devised in shape for the purpose of improving heat transfer coefficient and reducing pressure loss are known. For example, Patent Document 1 discloses a corrugated fin obtained by bending a plate-like fin into a wave shape. Patent Document 2 discloses a fin tube type heat exchanger in which a large number of minute dimples are provided on the surface of a fin. Patent Document 3 discloses a finned tube heat exchanger in which a triangular pyramid-shaped protrusion is provided on the surface of a fin. Patent Document 4 discloses a fin-tube heat exchanger in which a quadrangular pyramid-shaped protrusion is provided on the surface of a fin.
JP-A 64-90995 JP 7-239196 A JP-A 63-294494 JP-A-6-300474

  In recent years, further improvement in the performance of heat exchangers has been desired, and even if the specifications of conventional fin tube heat exchangers are optimized, satisfactory performance has not always been obtained. Therefore, a fin tube type heat exchanger having fins having a completely new shape has been awaited.

  This invention is made | formed in view of this point, The place made into the objective is providing the fin tube type heat exchanger with a small pressure loss, while having the outstanding heat transfer performance. Moreover, an object of this invention is to provide the fin for heat exchangers which can be employ | adopted suitably for a fin tube type heat exchanger. Moreover, an object of this invention is to provide the heat pump apparatus provided with the said finned tube type heat exchanger.

The present invention
A fin-tube heat exchanger for exchanging heat between the first fluid and the second fluid,
A plurality of fins arranged in parallel and spaced apart from each other to form a flow path for the first fluid;
A plurality of heat transfer tubes that pass through the plurality of fins and through which the second fluid should flow;
The plurality of heat transfer tubes are arranged in a predetermined row direction intersecting the flow direction of the first fluid, and the first heat transfer tubes,
A second heat transfer tube arranged in parallel with the first heat transfer tube and arranged downstream of the first heat transfer tube with respect to the flow direction of the first fluid;
Each of the plurality of fins includes a fin base portion in which a plurality of through holes for arranging the plurality of heat transfer tubes are formed, and
A first raised portion provided so as to protrude from the fin base between two adjacent first heat transfer tubes; and
A second raised portion provided so as to protrude from the fin base between two adjacent second heat transfer tubes;
A first notch penetrating the fin is formed so as to show an arcuate shape in a plan view along a boundary between the upstream portion of the first raised portion and the fin base portion.
A second notch penetrating the fin is formed so as to show an arcuate shape in plan view along the boundary between the upstream portion of the second raised portion and the fin base.
A first gap based on the first cut is formed between the upstream portion of the first raised portion and the fin base,
A second gap based on the second cut is formed between the upstream portion of the second raised portion and the fin base,
The first fluid can flow from the first main surface side of the fin to the second main surface side through the first gap and the second gap,
Providing a third notch in the fin base surface between the first raised portion and the second heat transfer tube;
A first fin on the windward side with respect to the flow direction of the first fluid on the fin base surface;
A second fin on the windward side with respect to the flow direction of the first fluid on the fin base surface;
Forming a fin connecting portion connecting the first fin and the second fin;
Provided is a finned tube heat exchanger in which first fins and second fins are arranged in a staggered manner.

  Of course, not all the ridges need to have cuts formed therein, and for example, cuts may be formed every other row direction.

The present invention also provides:
A plate-like fin used in a finned tube heat exchanger for exchanging heat between the first fluid and the second fluid,
The first gap is formed by partially cutting the fin base and / or the first raised portion along the first cut,
The second gap is formed by partially cutting off the fin base and / or the second raised portion along the second cut,
The first raised portion is provided only between two adjacent first heat transfer tubes, and the maximum width in the column direction is larger than the outer diameter of the first heat transfer tubes,
Only one of the second raised portions is provided between two adjacent second heat transfer tubes, and the maximum width in the column direction is larger than the outer diameter of the second heat transfer tubes,
An upstream portion of the first and second raised portions provides a heat exchanger fin having a semicircular or semielliptical shape in plan view.

The present invention also provides:
The upstream portion of the first raised portion and the second raised portion may have a triangular wing shape in plan view.

The present invention also provides:
The first raised portion and the second raised portion may have an elliptical hill, a circular hill, a polygonal pyramid, or a conical shape.

The present invention also provides:
A compressor for compressing the refrigerant;
A radiator that dissipates the refrigerant compressed by the compressor;
An expansion mechanism for expanding the refrigerant radiated by the radiator;
An evaporator for evaporating the refrigerant expanded by the expansion mechanism,
Provided is a heat pump device in which at least one of a radiator and an evaporator includes the above-described finned tube heat exchanger.

  According to said fin tube type heat exchanger, a heat transfer performance can be improved by the front edge effect of the notch of the front part of a 1st protruding part and a 2nd protruding part. Further, by shifting the first fin and the second fin by approximately a half fin pitch, the heat transfer performance can be improved by the front edge effect of a part of the front portion of the second fin. In addition, a gap is formed between the upstream portion of the raised portion and the fin base, and the first fluid can flow from the first main surface side to the second main surface side by the gap. Yes. Therefore, it is possible to suppress an increase in pressure loss due to the provision of the raised portion. These effects combine to suppress an increase in pressure loss and improve the heat transfer performance of the fins. As a result, a higher performance fin tube heat exchanger can be realized.

  Further, by adopting the fin tube type heat exchanger, COP (coefficient of performance) of the heat pump apparatus can be improved.

(First embodiment)
Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.

  FIG. 1 is an overall perspective view of a finned tube heat exchanger according to the present invention. The finned tube heat exchanger 1 (hereinafter also simply referred to as “heat exchanger 1”) has a predetermined interval on the windward side in the flow direction (X direction) of the first fluid in order to form a flow path of the first fluid. The plurality of first fins 3a arranged in parallel with each other, the plurality of second fins 3b arranged in parallel at a predetermined interval on the leeward side in the flow direction (X direction) of the first fluid, and the fins 3a, 3b A connection portion 3c that is shifted by approximately a half fin pitch in the direction and connected, and a plurality of heat transfer tubes 2a and 2b that pass through the fins 3a and 3b are provided. The heat exchanger 1 exchanges heat between the first fluid that flows along the main surfaces of the fins 3a and 3b and the second fluid that flows inside the heat transfer tubes 2a and 2b. In the present embodiment, the air A flows along the main surfaces of the fins 3a and 3b, and the refrigerant B flows inside the heat transfer tubes 2a and 2b. The type and state of the fluid flowing inside the heat transfer tubes 2a and 2b and the fluid flowing along the main surfaces of the fins 3a and 3b are not particularly limited. These fluids may be gas or liquid.

As shown in FIG. 1, the plurality of heat transfer tubes 2 a and 2 b include a plurality of first heat transfer tubes 2 a and a first heat transfer tube 2 a arranged in a row in a predetermined row direction that intersects the flow direction of the air A. And a plurality of second heat transfer tubes 2b arranged in a line downstream of the first heat transfer tubes 2a with respect to the flow direction of the air A. The 1st heat exchanger tube 2a is connected to one so that refrigerant B may flow in order. Similarly, the 2nd heat exchanger tube 2b is connected to one so that the refrigerant B may flow in order. However, these heat transfer tubes 2a and 2b are not necessarily connected to one. Moreover, the 1st heat exchanger tube 2a and the 2nd heat exchanger tube 2b may be connected to one.

The heat exchanger 1 is used 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 3a and 3b and the row direction (Z direction) of the heat transfer tubes 2a and 2b. The However, the airflow direction may be slightly inclined from the X direction as long as a sufficient amount of heat exchange can be ensured. In the present specification, the flow direction of the air A is the X direction, the longitudinal direction of the fins 3a and 3b, which is the direction in which the heat transfer tubes 2a and 2b are arranged, is the Z direction, and is perpendicular to the main surface of the fins 3a and 3b. The stacking direction (Y direction), which is a simple direction, is defined as the height direction.

  The fins 3a and 3b have a substantially rectangular and flat plate shape, and are arranged along the Y direction shown in FIG. In the present embodiment, the fins 3a and 3b are arranged at a constant interval (fin pitch). The fin pitch is, for example, 1.0 mm to 1.5 mm. However, the fin pitch is not necessarily constant, and may be different. The fins 3a and 3b can be made of, for example, a punched metal plate having a thickness of 0.08 to 0.2 mm. The metal plate is, for example, an aluminum flat plate. The surfaces of the fins 3a and 3b are preferably subjected to a hydrophilic treatment such as boehmite treatment or application of a hydrophilic paint, or a water repellent treatment.

  FIG. 2 is a plan view of fins used in the heat exchanger shown in FIG. FIG. 3 is a perspective view of the fin. 4 is a cross-sectional view taken along line II of the fin shown in FIG. FIG. 5 is a II-II cross-sectional view of the fin shown in FIG. Although FIG. 2 is a plan view of the fin, the heat transfer tubes 2a and 2b are also shown.

  As shown in FIG. 2, the fin base 3 includes a first fin 3a, a second fin 3b, a connecting portion 3c, a first raised portion 5a, and a second raised portion 5b. The fin base portion 3 is a flat portion in which a plurality of through holes 7k and 7j for arranging the heat transfer tubes 2a and 2b are formed. The plurality of through holes 7k, 7j are arranged in a row direction (Z direction) orthogonal to the flow direction of the air A so as to penetrate the first main surface 4p and the second main surface 4q (see FIG. 5) of the fins 3a, 3b. ) And a plurality of first through holes 7k formed at equal intervals, and a plurality of second through holes 7j formed at equal intervals in the Z direction.

  The first heat transfer tubes 2a are arranged in the first through holes 7k in the front row close to the front edge 30p of the first fin 3a, and the second heat transfer tubes 2b in the second through holes 7j in the rear row close to the front edge 30q of the second fin 3b. Is placed.

  In the plan view of FIG. 2, a straight line connecting the centers of two adjacent first through holes 7k, 7k is parallel to the front edge 30p of the first fin 3a. Similarly, a straight line connecting the centers of the second through holes 7j and 7j is also parallel to the front edge 30q of the second fin 3b.

  The heat transfer tubes 2a and 2b are made of a highly conductive metal such as copper or copper alloy, and are smooth tubes having a smooth inner surface or grooves with a groove formed on the inner surface. When the heat transfer tubes 2a and 2b are in close contact with the fin collars 31 and 32 (see FIG. 4) formed around the through holes 7k and 7j, the first heat transfer tubes 2a, the first fins 3a, and the second heat transfer tubes 2b The heat transfer between the second fins 3b is promoted.

  In the present embodiment, the diameter (outer diameter D1) of the first heat transfer tube 2a disposed in the first through hole 7k is the same as the diameter (outer diameter D2) of the second heat transfer tube 2b disposed in the second through hole 7j. It is. The outer diameter D1 of the first heat transfer tube 2a and the outer diameter D2 of the second heat transfer tube 2b can be adjusted within a range of 1 mm to 20 mm, for example. The outer diameters D1 and D2 of the heat transfer tubes 2a and 3b coincide with the opening diameters of the through holes 7k and 7j formed in the fins 3a and 3b. Therefore, the opening area of the second through hole 7j is equal to the opening area of the first through hole 7k.

The reference line P1 is a straight line passing through the center C11 of the first through hole 7k and orthogonal to the Z direction in the plan view of the fin base 3. The reference line P2 is a straight line located in the middle of the two adjacent first through holes 7k, 7k and parallel to the reference line P1, in other words, the center C11 of the two adjacent first through holes 7k, 7k, This is a perpendicular bisector of a line segment connecting C11. The reference line P1 is also a straight vertical bisector that connects the centers C21 and C21 (the centers of the second heat transfer tubes 2b) of the two adjacent second through holes 7j and 7j.

  The first raised portion 5a will be described in detail. Each first raised portion 5 a is a hill-shaped portion that is molded so as to protrude from the fin base 3, and contributes to an increase in the heat transfer area of the fin base 3. As shown in FIG. 2, the upstream portion 6a of the raised portion 5a in the flow direction of the air A has a semi-elliptical shape in plan view. A semicircular shape may be employed instead of the semielliptical shape. Then, along the boundary between the semi-elliptical upstream portion 6a and the fin base 3, a cut 9a penetrating the fin 3a in the thickness direction is formed so as to show an arch shape in plan view. And the 1st clearance gap 8a based on the notch | incision 9a is formed between the upstream part 6a of the 1st protruding part 5a, and the fin base part 3, The air A is the 1st main surface 4p side of the fin 3a through the 1st clearance gap 8a. To the second main surface 4q side (see FIG. 5). The perspective view of FIG. 3 most accurately represents the state of the first gap 8a. The same can be said for the second raised portion 5b.

  In the fins 3a and 3b of this embodiment, the 1st clearance gap 8a and the 2nd clearance gap 8b which can distribute | circulate the air A only in the upstream of the protruding parts 5a and 5b are formed. The air A that has passed through the first gap 8a and the second gap 8b and has moved from the first main surface 4p side to the second main surface 4q side does not return to the first main surface 4p side again. As a result, a smooth flow of air A can be formed, which is effective in suppressing an increase in pressure loss.

  It should be noted that the semicircular or semi-elliptical shape in plan view is an image shape (image contour) that appears when the raised portions 5a and 5b are orthogonally projected on a plane parallel to the main surfaces 4p and 4q of the fins 3a and 3b. It means semi-circular or semi-elliptical. In the present embodiment, the raised portions 5a and 5b are all hill-shaped, but a spire-like shape such as a cone, an elliptical cone, or a polygonal pyramid may be employed.

  Only one first raised portion 5a is provided between two adjacent first heat transfer tubes 2a, 2a. As shown in FIG. 2, the maximum length L1 regarding the Z direction of the 1st protruding part 5a is more than the outer diameter D1 of the 1st heat exchanger tube 2a. Moreover, the equivalent diameter (diameter of a circle with the same area) of the 1st protruding part 5a in the top view of the fin 3a is larger than the outer diameter D1 of the 1st heat exchanger tube 2a. In the present embodiment, the length of the line segment connecting the one end 11a and the other end 12a of the notch 9a formed adjacent to the upstream portion 6a of the first raised portion 5a with the shortest distance is the first raised portion 5a. This corresponds to the maximum length L1 in the Z direction. A line segment connecting the one end 11a and the other end 12a of the cut 9a coincides with the short axis of the semi-elliptical upstream portion 6a. When the upstream portion 6a of the first raised portion 5a is semicircular in plan view, the line segment matches the diameter of the circle. The same can be said for the second raised portion 5b.

  For example, when a large number of small raised portions are formed between two adjacent heat transfer tubes as in the prior art, it is difficult to increase the height of the raised portions due to processing problems. And such a small protruding part has a weak effect | action which induces the air A. FIG. In addition, the raised portion with an insufficient height has a low rate of increase in the heat transfer area with respect to the unprocessed flat plate, and the effect of suppressing the development of the boundary layer cannot be expected so much. On the other hand, according to the raised portions 5a and 5b provided on the fins 3a and 3b of the present embodiment, the maximum length L1 in the Z direction is set to the outer diameter D1 of the first heat transfer tube 2a or the outside of the second heat transfer tube 2b. Since the height H (see FIG. 4) can be sufficiently obtained by setting the diameter D2 or more, the action of guiding the air A toward the heat transfer tubes 2a and 2b is strong. In addition, it is possible to maximize the rate of increase of the heat transfer area with respect to the unprocessed flat plate, and also has a strong effect of suppressing the development of the boundary layer, so that sufficient improvement of the heat transfer performance of the fins 3a and 3b is expected. it can.

Furthermore, as shown in FIG. 2, the first raised portion 5a provided in the first fin 3a of the present embodiment reaches a region (downstream region) sandwiched between two adjacent second heat transfer tubes 2b, 2b. The downstream portion 7a connected to the upstream portion 6a has a shape extending while narrowing the width in the column direction (Z direction). As shown in the cross-sectional view of FIG. 4, the first raised portion 5a has no step from the upstream end to the downstream end in the X direction, and the height continuously changes. The upstream end of the first raised portion 5a is located closer to the front edge 30p of the fin 3a than the first heat transfer tube 2a, and the downstream end of the first raised portion 5a is a flow of air A more than the first heat transfer tube 2a. Located downstream in the direction. The length L2 in the X direction of the first raised portion 5a is larger than the outer diameter D1 of the first heat transfer tube 2a and larger than the maximum length L1 in the Z direction. The same applies to the second heat transfer tube 2b, the front edge 30q of the fin 3b, and the second raised portion 5b as shown in the sectional views of FIGS.

  As shown in FIG. 2, the apex C12 of the upstream portion 6a of the first raised portion 5a is located downstream of the center C11 of the first heat transfer tube 2a. The upstream end of the first raised portion 5a is located upstream of the center C11 of the first heat transfer tube 2a. The height H of the first raised portion 5a is represented by the height from the first main surface 4p of the fin base 3 to the vertex C12 of the first raised portion 5a, and is smaller than the fin pitch FP. However, the height H of the first raised portion 5a is not particularly limited, and can be adjusted, for example, within a range of 1/3 to 2/3 of the fin pitch FP. In the present embodiment, the height H of the first raised portion 5a is set to approximately ½ of the fin pitch FP. By adjusting the height H of the first raised portion 5a within such a range, it is possible to balance the expansion of the heat transfer area and the suppression of an increase in pressure loss. The same can be said for the second raised portion 5b.

  The height of the first raised portion 5a is constant from the upstream end to the vertex C12 in the X direction, and the height monotonously decreases from the vertex C12 to the downstream end. In this way, the air A smoothly flows through the upstream portion 6 of the first raised portion 5a, which is effective in reducing pressure loss. However, the shape of the 1st protruding part 5a is not limited to this. For example, the height of the upstream portion 6a of the first raised portion 5a may monotonously decrease from the vertex C12 toward the upstream end (see FIG. 7), or the first raised portion from the upstream end toward the downstream end. The height of the part 5a may increase monotonously (see FIG. 8). According to the former, the flow rate of the air A flowing above the upstream portion 6a is increased, and the heat transfer rate is improved. According to the latter, the flow rate of the air A flowing under the upstream portion 6a is increased, and the heat transfer rate is improved. Further, as shown in FIG. 9, in a cross section including the upstream end 5s and the downstream end 5t of the first raised portion 5a and orthogonal to the Z direction, the outer shape 5f (outline) is expressed by y = Kcos (x) where K is a constant. The shape of the first raised portion 5a can be set so as to draw a cosine curve. Here, x is assumed to be −180 ° ≦ x ≦ 180 ° (or −90 ° ≦ x ≦ 90 °), and it is assumed that the first raised portion 5a also exists in the portion where the first gap 8a is formed. The above x shall be defined. Further, the shape of the first raised portion 5a may be set so that the outer shape 5f draws an arc instead of the cosine curve. Furthermore, the shape of the 1st protruding part 5a can be set so that the external shape (contour) which appears in the cross section orthogonal to a X direction may draw a cosine curve and a circular arc as shown in FIG. The same can be said for the second raised portion 5b.

As shown in FIGS. 3 and 4, the first gap 8a formed between the upstream portion 6a of the first raised portion 5a and the fin base portion 3 has an upstream portion 6a of the first raised portion 5 along the notch 9a. It can be formed by being partially cut into a strip. Instead of or together with the upstream portion 6a of the first raised portion 5a, the fin base 3 side may be cut off. By cutting off a part of the fin 3a, the first gap 8a having a sufficiently large width can be formed even when the height H of the first raised portion 5a is not so large. However, if a notch 9a is formed along the boundary between the fin base 3 and the first raised portion 5a and the upstream portion 6a of the first raised portion 5a is deformed so as to be lifted in the Y direction, a part of the fin 3a is obtained. It is not necessary to cut and process. In addition, the front edge of the upstream part 6a of the 1st protruding part 5a is not necessarily limited to a curve like this embodiment, For example, linear shape and polygonal shape may be sufficient. For example, a part of the fin 3a can be cut and processed so that the upstream portion 6a of the first raised portion 5a becomes a triangle that is tapered toward the upstream side. The same can be said for the second raised portion 5b.

  As shown in FIGS. 2 and 3, the fins 3 a and the fins 3 b are connected by a connecting portion 3 c to constitute the fin base portion 3. The connecting portion 3c is located on the upstream side of the second raised portion 5b and holds the positional relationship between the fins 3a and the fins 3b. The fin 3a and the fin 3b are shifted by substantially half the fin pitch FP with respect to the Y direction. Thereby, heat transfer performance can be improved by the front edge effect at the front edge 30q of the fin 3b. The connecting portion 3c is not limited to the shape as in the present embodiment, and may have a shape as shown in FIG. With such a shape, the processability is excellent.

  Next, the operation of the fins 3a and 3b will be described.

  As shown in FIG. 3, the airflow A1 from the front of the fin 3a first collides with the upstream portion 6a of the first raised portion 5a. At this time, a thin temperature boundary layer is formed on the surface of the upstream portion 6a by the so-called leading edge effect, and the heat transfer coefficient is improved. On the other hand, when a part of the airflow A1 enters the first gap 8a adjacent to the upstream portion 6a, the pressure loss can be reduced. A part of the airflow A2 riding on the upstream portion 6a is guided to the left and right toward the first heat transfer tube 2a, and wraps around the rear of the first heat transfer tube 2a. By such air wraparound, generation of a dead water area behind the first heat transfer tube 2a is suppressed, and the heat transfer rate is improved.

  Next, the airflow A3 that wraps around the first heat transfer tube 2a collides with the second raised portion 5b of the fin 3b. As in the case of the first raised portion 5a, the upstream portion 6b can improve the heat transfer coefficient due to the leading edge effect and reduce the pressure loss. Further, a part of the airflow A3 that rides on the second raised portion 5b and goes downstream is guided left and right toward the second heat transfer tube 2b in the rear row, and goes around the second heat transfer tube 2b. Such air wraparound suppresses generation of a dead water area behind the second heat transfer tube 2b and improves the heat transfer coefficient.

  On the other hand, the airflow that has passed through the first gap 8a merges with the airflow riding on the upstream portion 6a on the first raised portion 5a of the fin 3a arranged one step below, and on the first raised portion 5a. An air flow A4 is formed downstream. As described above, a part of the airflow A4 wraps around the second heat transfer tube 2b of the fin 3b.

  Further, according to the fins 3a and 3b of the present embodiment, the air flow rate tends to increase in the region sandwiched between the first raised portion 5a and the first heat transfer tube 2a. Therefore, the heat transfer coefficient is improved on the side surface of the first heat transfer tube 2a (side surface of the fin collar 31). The accelerated air collides with the second raised portion 5b on the downstream side. Thereby, a temperature boundary layer becomes thin in the upstream part 6b of the 2nd protruding part 5b, and the improvement of a heat transfer rate is achieved.

  By the way, when the thickness of the fins 3a and 3b is small or when the raised portions 5a and 5b are large, when the raised portions 5a and 5b are formed by pressing, the fin base portion 3 is twisted or unintentionally uneven. There is a risk of Therefore, as shown in FIGS. 2 and 6, when the notch is formed in the fin base 3 to form the base region of the connecting portions 3c and 3d, and the raised portions 5a and 5b are formed in the connecting portions 3c and 3d. It is advisable to absorb twists and irregularities. According to the connecting portions 3c and 3d, when the pressing mold is pressed against the fin base 3, excessive stress is hardly generated on the fin base 3, and the raised portion 5a having an appropriate shape and size is obtained. , 5b can be formed. The positions where the connecting portions 3c and 3d are formed are not particularly limited. However, as shown in FIGS. 2 and 6, if the connecting portions 3c and 3d are formed between the first heat transfer tube 2a and the second raised portion 5b, the twist and irregularities are absorbed. High effect is obtained. In addition, the connecting portions 3c and 3d are formed by pressing so that the fins 3a and 3b are shifted by about half the fin pitch FP with respect to the Y direction.

The raised portions 5a and 5b in which the notches 9a and 9b are formed at the boundary with the fin base 3, and the raised portions that are not formed in the notches 9a and 9b but have the same shape as the raised portions 5a and 5b, You may make it provide alternately in the front row of fin 3a, 3b.
Further, regarding the second raised portion 5b, the notch 9b is not essential. For example, instead of the second raised portion 5b in which the notch 9b is formed at the boundary with the fin base 3, the notch 9b is cut at the boundary with the fin base 3. Although 9b is not formed, the fin 3b may be provided with a raised portion having the same shape as the second raised portion 5b. Of course, the second raised portion 5b in which the cut 9b is formed and the raised portion in which the cut 9b is not formed may be mixed (for example, provided alternately).

The fin tube heat exchanger 1 described above can be applied to a heat pump device that heats or cools an object such as air or water. As shown in FIG. 10, the heat pump device 70 includes a compressor 71 that compresses the refrigerant, a radiator 72 that radiates the refrigerant compressed by the compressor 71, and an expansion valve 73 that expands the refrigerant radiated by the radiator 72. And an evaporator 74 for evaporating the refrigerant expanded by the expansion valve 73. The compressor 71, the radiator 72, the expansion valve 73, and the evaporator 74 are connected by a pipe 75 to form a refrigerant circuit. Instead of the expansion valve 73, an expander may be employed. The radiator 72 and the evaporator 74 can be configured to include the finned tube heat exchanger 1 of the present invention.
(Example)
The characteristics of the finned tube heat exchanger according to the present invention were examined by computer simulation. Specifically, a computer simulation was performed on a finned tube heat exchanger using the fin base 3 shown in FIG. Example 1 is an example using the fin base 3. As a comparative example, the same computer simulation was performed for a conventional fin-tube heat exchanger using corrugated fins. The characteristics examined by computer simulation are heat transfer coefficient and pressure loss. The computer simulation was performed under the following conditions using “Fluent Ver. 6” manufactured by Fluent Asia Pacific.
<Common conditions for Example 1 and Comparative Example 1>
Fin size: 27mm (X direction)
Fin thickness: 0.1mm
Fin pitch: 1.49mm
Front wind speed Vair: 1m / sec
<Conditions of Example 1>
1st heat transfer tube outer diameter D1: 7mm
Tube pitch of the first heat transfer tube: 21 mm (Z direction)
Outer diameter D2 of the second heat transfer tube: 7mm
Tube pitch of second heat transfer tube: 21 mm (Z direction)
Height H of the raised portions 5a and 5b: 0.765 mm
Maximum length L1 of the raised portions 5a, 5b in the Z direction: 10 mm
Maximum length L2 of the raised portions 5a and 5b in the X direction: 13 mm
<Conditions of Comparative Example 1>
Shape: Corrugated Heat transfer tube arrangement: Staggered Tube pitch: 21 mm (Z direction)
Heat transfer tube outer diameter: 7.0 mm
Height difference between ridge and valley: 1.49mm
Table 1 shows the results of the computer simulation of Example 1 and Comparative Example 1.

  As can be seen from Table 1, according to the finned tube heat exchanger of the present embodiment, the pressure loss ΔP is comparable to that of the conventional finned tube heat exchanger having corrugated fins (Examples). 1), the heat transfer coefficient α increased (an improvement of 7% in Example 1).

The perspective view of the fin tube type heat exchanger concerning the present invention The top view of the fin of the fin tube type heat exchanger shown in FIG. The perspective view of the fin shown in FIG. II sectional view of the fin shown in FIG. II-II sectional view of the fin shown in FIG. The top view which shows another form of a connection part Sectional drawing which shows the other example of the shape of a 1st protruding part Sectional drawing which similarly shows another example of the shape of a 1st protruding part Schematic diagram showing the shape of the first raised portion Configuration diagram of heat pump device

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Fin tube type heat exchanger 2a 1st heat exchanger tube 2b 2nd heat exchanger tube 3 Fin base part 3a 1st fin 3b 2nd fin 4p 1st main surface 4q 2nd main surface 5a 1st protruding part 5b 2nd protruding part 6a 1st 1 upstream portion 6b upstream portion 7a upstream portion 7a upstream portion 7b downstream portion 1b raised portion 7b downstream portion 2nd raised portion 7k first through hole 7j second through hole 8a first clearance 8b second clearance 9a second 1 notch 9b second notch 11a first notch end 11b second notch end 12a first notch other end 12b second notch other end 30p first fin leading edge 30q second fin leading edge 31 first fin Color 32 The color of the second fin

Claims (7)

A fin-tube heat exchanger for exchanging heat between the first fluid and the second fluid,
A plurality of fins arranged in parallel and spaced apart from each other to form a flow path for the first fluid;
A plurality of heat transfer tubes that pass through the plurality of fins and through which the second fluid should flow;
The plurality of heat transfer tubes are arranged in a predetermined row direction intersecting the flow direction of the first fluid, and the first heat transfer tubes,
A second heat transfer tube arranged in parallel with the first heat transfer tube and arranged downstream of the first heat transfer tube with respect to the flow direction of the first fluid;
Each of the plurality of fins includes a fin base portion in which a plurality of through holes for arranging the plurality of heat transfer tubes are formed, and
A first raised portion provided so as to protrude from the fin base between two adjacent first heat transfer tubes; and
A second raised portion provided so as to protrude from the fin base between two adjacent second heat transfer tubes;
A first notch penetrating the fin is formed so as to show an arcuate shape in a plan view along a boundary between the upstream portion of the first raised portion and the fin base portion.
A second notch penetrating the fin is formed so as to show an arcuate shape in plan view along the boundary between the upstream portion of the second raised portion and the fin base.
A first gap based on the first cut is formed between the upstream portion of the first raised portion and the fin base,
A second gap based on the second cut is formed between the upstream portion of the second raised portion and the fin base,
The first fluid can flow from the first main surface side of the fin to the second main surface side through the first gap and the second gap,
Providing a third notch in the fin base surface between the first raised portion and the second heat transfer tube;
A first fin on the windward side with respect to the flow direction of the first fluid on the fin base surface;
A second fin on the windward side with respect to the flow direction of the first fluid on the fin base surface;
Forming a fin connecting portion connecting the first fin and the second fin;
A finned tube heat exchanger, wherein the first fin and the second fin are arranged in a staggered manner. The first gap is formed by partially cutting the fin base and / or the first raised portion along the first cut,
2. The finned tube heat exchanger according to claim 1, wherein the second gap is formed by partially cutting the fin base and / or the second raised portion along the second cut. The first raised portion is provided only between two adjacent first heat transfer tubes, and the maximum width in the column direction is larger than the outer diameter of the first heat transfer tubes,
The said 2nd protruding part is provided only between two said 2nd heat exchanger tubes adjacent, and the largest width regarding the said row direction is larger than the outer diameter of the said 2nd heat exchanger tube. The described finned tube heat exchanger.   2. The finned tube heat exchanger according to claim 1, wherein an upstream portion of the first raised portion and the second raised portion has a semicircular or semielliptical shape in plan view.   2. The finned tube heat exchanger according to claim 1, wherein upstream portions of the first raised portion and the second raised portion have a triangular wing shape in a plan view.   2. The finned tube heat exchanger according to claim 1, wherein the first raised portion and the second raised portion have a shape of an elliptical hill, a circular hill, a polygonal pyramid, or a cone. A compressor for compressing the refrigerant;
A radiator that dissipates the refrigerant compressed by the compressor;
An expansion mechanism for expanding the refrigerant radiated by the radiator;
An evaporator for evaporating the refrigerant expanded by the expansion mechanism,
The heat pump device, wherein at least one of the evaporator and the radiator includes the finned tube heat exchanger according to claim 1.

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