JP2013224800A - Finned tube heat exchanger - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a finned tube heat exchanger which improves heat-transfer performance of a slip stream section of a heat-transfer tube and also improves drainage property for the water generated at the surface of a fin.SOLUTION: A finned tube heat exchanger includes: a plurality of fins 1; and a plurality of heat transfer tubes 2 that pass through the plurality of fins 1 and have a fluid flowing therethrough. The fin 1 includes a tube periphery part 4 that is formed at the periphery of the heat transfer tube 2 and a convex part 5 that is formed so as to surround the tube periphery part. The convex part 5 is configured so as to include fluid paths 9, 10 that communicate the front and the back of the fin 1, and thus, air flows Sa, Sb that flow into a flow interchange section of the heat transfer tube 2 are generated by the convex part 5, thereby improving heat-transfer performance of a slip stream section of the heat transfer tube 2, and also the water generated on the fin 1 is guided downward the gravity direction by the fluid paths 9, 10, thereby improving drainage property.

Description

  The present invention relates to a finned tube heat exchanger used for heat exchange of a refrigerant.

  Conventionally, this kind of finned-tube heat exchanger has a substantially circular convex portion so as to surround the insertion hole of the heat transfer tube in order to reduce the dead water area in the downstream portion of the heat transfer tube. In order to drain the condensed water adhering to the fins when used as, there is one in which a flat portion is provided on a part of the convex portion (see, for example, Patent Document 1).

  FIG. 13 shows a conventional finned tube heat exchanger described in Patent Document 1. As shown in FIG.

  13A is a partial plan view of the fin 101, FIGS. 13B and 13C are cross-sectional views taken along lines AA and BB in FIG. 13A, respectively. (D) has shown the elements on larger scale of the broken line C of Fig.13 (a).

  As shown in FIG. 13, the conventional fin tube heat exchanger is arranged in parallel at regular intervals, and the fins 101 in which air flows between them are inserted into the fins 1 at a predetermined step pitch and row pitch at a substantially right angle. A heat transfer tube 102 through which the refrigerant flows, a fin collar 103 that is raised from the fin 101 and into which the heat transfer tube 102 is inserted, and an annular flat tube peripheral portion 104 that surrounds the fin collar 3 on the fin 1. And an annular convex portion 105 surrounding the periphery of the tube peripheral portion 104. Moreover, the convex part 105 is comprised by the inclined surface 105a inclined to the heat exchanger tube 2 side, and the inclined surface 105b inclined to the opposite side to the inclined surface 105a.

  Accordingly, as shown in FIG. 13 (d), the dead water region D is reduced by attracting the air flows Sa and Sb flowing to the back of the heat transfer tube 102 by the convex portion 105.

  Further, as shown in FIG. 14, a flat portion 106 is provided in a part below the convex portion 105 with respect to the gravity direction G. Thereby, when a fin tube heat exchanger is used as an evaporator, the condensed water 120 adhering to the fin 101 is drained through the flat part 106, and the heat-transfer performance is improved.

JP-A-9-203593

  However, in the conventional configuration, as shown in FIG. 13 (d), an air flow Sc (shown by a broken line) leaking from the flat portion 106 is generated, and it is difficult to increase the air volume at the downstream portion of the heat transfer tube 102. Had the problem of being.

  Further, the provision of the flat portion 106 has a problem that the heat transfer area is reduced and the heat transfer performance is lowered.

The present invention solves the above-mentioned conventional problems, and provides a finned tube heat exchanger that improves the heat transfer performance of the downstream portion of the heat transfer tube and improves the drainage of water generated on the surface of the fins. The purpose is to do.

  In order to solve the conventional problem, a finned tube heat exchanger according to the present invention includes a plurality of fins and a plurality of heat transfer tubes that pass through the plurality of fins and in which a fluid flows. A pipe peripheral part formed around the heat transfer pipe and a convex part formed so as to surround the pipe peripheral part, and a fluid path communicating the front and back of the fin is provided in the convex part. It is characterized by.

  Thereby, in the convex part surrounding the periphery of the heat transfer tube, while increasing the air flow flowing into the heat transfer tube wake part, the water generated on the fin by the fluid flow path is smoothly guided downward in the gravity direction, Drainage can be improved.

  ADVANTAGE OF THE INVENTION According to this invention, while improving the heat transfer performance of the downstream part of a heat exchanger tube, the fin tube heat exchanger which improved the drainage property of the water which generate | occur | produces on the surface of a fin can be provided.

The block diagram of the finned-tube heat exchanger in the 1st Embodiment of this invention (A) The fragmentary top view of the fin of the fin tube heat exchanger, (b) AA sectional drawing of Fig.2 (a), (c) BB sectional drawing of Fig.2 (a), (d) figure Partial enlarged view of 2 (a) Explanatory drawing of drainage action of fins of same finned tube heat exchanger (A) The partial top view of the fin of another shape of the fin tube heat exchanger, (b) AA sectional view at the time of laminating | stacking a fin in FIG. 4 (a), (c) Fin in FIG. 4 (a) BB cross section when laminating Explanatory drawing of drainage action of fins with different shapes of the finned tube heat exchanger (A) The partial plan view of the fin of the finned-tube heat exchanger in Embodiment 2 of this invention, (b) The partial plan view of the another-shaped fin of the same finned-tube heat exchanger (A) The fragmentary top view of the fin of the finned-tube heat exchanger in Embodiment 3 of this invention, (b) AA sectional drawing of Fig.7 (a), (c) BB of FIG.7 (a) Sectional view, (d) Partial enlarged view of FIG. Explanatory drawing of drainage action of fins of same finned tube heat exchanger Image of heat conduction of fin of the finned tube heat exchanger (A) The partial top view of the fin of another shape of the fin tube heat exchanger, (b) AA sectional view at the time of laminating | stacking a fin in Fig.10 (a), (c) Fin in FIG.10 (a) BB cross section when laminating Explanatory drawing of drainage action of fins with different shapes of the finned tube heat exchanger Partial plan view of another fin shape of the finned tube heat exchanger (A) Partial plan view of fins of a conventional fin tube heat exchanger, (b) AA sectional view of FIG. 13 (a), (c) BB sectional view of FIG. 13 (a), (d) Partial enlarged view of FIG. Explanatory drawing of drainage action of fins of same finned tube heat exchanger

  A first invention includes a plurality of fins and a plurality of heat transfer tubes that pass through the plurality of fins and in which a fluid flows, and the fins are tube peripheral portions formed around the heat transfer tubes; The fin tube heat exchanger is characterized in that a fluid path that communicates the front and back of the fin is provided in the convex portion.

  As a result, the convex portion surrounding the periphery of the heat transfer tube increases the air flow flowing into the wake portion of the heat transfer tube, and smoothly guides the water on the fins downward in the direction of gravity through the fluid path, thereby improving drainage. Since it improves, heat transfer performance can be improved.

  In a second aspect of the invention, in particular, in the first aspect of the invention, the fin includes an inclined portion inclined in a wave shape with respect to the air flow direction, and the convex portion is inclined in the first direction of the heat transfer tube. And the second inclined surface inclined to the opposite side of the first inclined surface, and the inclined portion and the convex portion are connected via the second inclined surface. It is the fin tube heat exchanger characterized by these.

  As a result, the fin becomes a corrugated fin having a corrugated shape in which peaks and troughs are alternately continued, and the water that has passed through the fluid path is guided to the trough of the corrugated fin, so that the flow path of water on the fin As a result, the drainage performance of the fins can be further improved.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. Note that the present invention is not limited to the embodiments.

(Embodiment 1)
FIG. 1 is a configuration diagram of a finned-tube heat exchanger according to the first embodiment of the present invention, FIG. 2A is a partial plan view of fins of the finned-tube heat exchanger, and FIG. c) and (d) are AA sectional view and BB sectional view of FIG. 2A, respectively, a partially enlarged view of FIG. 2A, and FIG. 3 is a fin of the fin tube heat exchanger. 4 (a) is a partial plan view of the fin when the fin is a corrugated shape in the fin tube heat exchanger, and FIGS. 4 (b) and 4 (c) are respectively the same as FIG. Sectional drawing in the AA line at the time of laminating | stacking a fin in a) and a BB line, FIG. 5 is drainage action explanatory drawing when the fin of the fin tube heat exchanger is made into a corrugated shape.

  FIG. 1 is a finned tube heat exchanger mounted on, for example, an outdoor unit of an air conditioner, a heat pump water heater, or a heat pump hot water heater. The fin tube heat exchanger is arranged in a row through a plurality of fins 1 stacked at a predetermined interval Fp and through the fins 1 so as to form a flow path for the air flow S. The heat transfer tube 2 and the end plate 30 for fixing the fin tube heat exchanger when the fin tube heat exchanger is placed on the outdoor unit and for connecting the fin tube heat exchangers in a plurality of rows.

  As shown in FIGS. 2A to 2C, the fin 1 is formed in a flat plate shape, and air flows in from the direction indicated by the air flow S. A fin collar 3 is formed in the fin 1 as an insertion hole for the heat transfer tube 2, and a flat tube peripheral portion 4 is formed around the fin collar 3.

  Further, the fin 1 and the heat transfer tube 2 are joined by a fin collar 3 by expanding the heat transfer tube 2 by mechanical expansion or hydraulic expansion. Furthermore, the convex part 5 comprised by the inclined surface 5a which is a 1st inclined surface, and the inclined surface 5b which is a 2nd inclined surface is formed so that this pipe | tube surrounding part 4 may be surrounded.

  Here, the inclined surface 5a is inclined from the ridge line of the convex portion 5 toward the heat transfer tube 2 side, and the inclined surface 5b is an inclined surface inclined from the ridge line of the convex portion 5 toward the opposite side to the heat transfer tube 2. Is.

  In addition, although the convex part 5 is formed in the circular ring shape so that the circumference | surroundings of the heat exchanger tube 2 may be surrounded as shown to Fig.2 (a) and (d), the shape is not specifically limited, For example, it may be polygonal.

The protrusion 5 is formed with a cut 9 as a fluid path that communicates the front and back of the fin 1 along the ridgeline. In the present embodiment, the notch 9 is formed at a position including the upper end and the lower end of the convex portion 5 with respect to the direction of gravity.

  The width of the notch 9 is preferably about 0.05 mm to 0.5 mm so that water generated on the fin can be induced by capillary action. In addition, when the slit length L is about 0.5 Fp to 1.5 Fp with reference to the fin pitch Fp, water generated on the fin 1 is formed on the bridge across the stacked fins. This is preferable in that the phenomenon (bridge phenomenon) can be suppressed.

  Furthermore, if the notch 9 is formed in a range of about θ = ± 45 ° from the center line parallel to the gravity direction of the heat transfer tube 2, the notch 9 is formed at a position where water on the fin 1 is likely to accumulate. Therefore, it is preferable in that the water generated on the fin 1 can be smoothly guided.

  About the finned-tube heat exchanger comprised as mentioned above, the operation | movement and an effect | action are demonstrated below.

  In the finned tube heat exchanger in the present embodiment, air passing between the fins 1 and the refrigerant flowing in the heat transfer tubes 2 exchange heat. Here, the refrigerant flowing inside the heat transfer tube 2 is suitable, for example, R410A, propane, propylene, carbon dioxide, or the like having a low environmental load, but is not particularly limited thereto.

  As shown in FIG. 2 (d), the convex portion 5 formed on the fin 1 serves as a guide for the air flow S, and leaks the air flows Sa and Sb that circulate from the air flow S to the wake portion of the heat transfer tube. The dead water area D can be reduced without attracting.

  Next, the drainage effect | action of the fin 1 at this time is demonstrated using FIG. FIG. 3 is arranged in time series from the left.

  As shown in FIG. 3 (left), particularly when the finned tube heat exchanger is used as an evaporator, condensed water 20 in which moisture in the air is condensed is generated around the heat transfer tube 2. Here, since the notch 9 is formed in the convex part 5 along the ridgeline, the deposited condensed water 20 is guided to the back side of the fin 1 through the notch 9 (in FIG. 3), and Then, it will be guided downward in the direction of gravity through the fin 1 (right of FIG. 3).

  Further, the condensed water 20 flowing along the surface of the fin 1 is also guided to the back side of the fin 1 through the notch 9 formed at the upper end of the convex portion 5, and the condensation is guided to the back side of the fin 1. Water is guided along the edge of the convex portion 5 downward in the direction of gravity.

  As described above, the convex portion 5 formed so as to surround the tube peripheral portion 4 induces an air flow to the downstream portion of the heat transfer tube 2 to reduce the dead water area and is formed in the convex portion 5. Since the condensate 20 can be guided downward in the gravitational direction by utilizing the capillary phenomenon by the notches 9, the finned tube has improved drainage and has excellent heat transfer performance without reducing the heat transfer area. A heat exchanger can be provided.

  Moreover, in this Embodiment, since the notch 9 is provided along the ridgeline of the convex part 5, a heat exchanger can be assembled irrespective of the direction of the fin 1, and the work time in a manufacturing process is shortened. Production costs can be reduced.

As shown in FIGS. 4A to 4D, the fin 1 has a mountain portion 13, a valley portion 14, and a valley portion 14 a with respect to the air flow S, a valley portion 14 a, a mountain portion 13, and a valley portion. 14, mountain part 13, valley part 14a
It may be formed so as to be a corrugated M-shaped corrugated fin that is continuous at the first inclined portion 15 in this order. Here, the peak portion 13, the valley portion 14, and the valley portion 14 a are formed by the inclined portion 15 that is inclined with respect to the air flow S.

  Moreover, as shown to Fig.4 (a), the convex part 5 has the inclined surface 5a which inclines toward the heat exchanger tube 2 side from the ridgeline, and the inclined surface which inclines toward the opposite side to the heat exchanger tube 2 5b. Here, the convex part 5 and the 1st inclination part 15 are connected via the inclined surface 5b.

  Thereby, as shown in FIG. 5, for example, when a finned tube heat exchanger is used as an evaporator, even if condensed water 20 is generated (left in FIG. 5), the condensed water 20 that has precipitated is cut 9 Is guided to the back side of the fin 1 and further to the peak portion 13 of the corrugated fin (which becomes a valley portion when viewed from the back side of the fin) (in FIG. 5), the condensed water 20 is lower in the gravitational direction. It is guided and drained from time to time (right in Fig. 5).

  In this way, when the fin 1 is formed in a corrugated shape, a fluid flow path through which water flows is formed by the notches 9 and the mountain-valley shape, so that the drainage can be further improved.

  Further, when the fin 1 has a corrugated shape, as shown in FIG. 4 (b), the air flow becomes a meandering air flow Sc, so that the temperature boundary layer can be made thin to promote heat transfer, The heat transfer performance of the heat exchanger can be improved.

  In FIG. 4, the fin 1 is formed as an M-shaped corrugated fin, but may be a V-shaped corrugated fin in which only one peak 13 is formed on the fin 1.

  In addition, in this Embodiment, although the heat exchanger tube 2 was described as a round tube, the heat exchanger tube 2 may not be a round tube but may be a flat tube, for example.

(Embodiment 2)
6 (a) and 6 (b) are partial plan views of fins of the finned tube heat exchanger according to the second embodiment of the present invention. In addition, the same code | symbol is attached | subjected about the part similar to other embodiment, and the detailed description is abbreviate | omitted.

  The difference between the present embodiment and other embodiments is that a small hole 10 is formed as a fluid path.

  The small holes 10 preferably have a diameter of about 0.2 mm to 1.0 mm so that water generated on the fins can be induced by capillary action. Moreover, as shown to Fig.6 (a) and (b), it is desirable to form above the convex part 5 and the downward direction.

  Thereby, since the drainage can be improved while ensuring the rigidity of the fin 1, the assemblability can be improved.

  Further, as shown in FIG. 6B, by forming the fin 1 into an M-shaped corrugated shape, the temperature boundary layer can be thinned to promote heat transfer, and the heat transfer performance as a heat exchanger can be improved. Can be improved.

(Embodiment 3)
FIG. 7 (a) is a partial plan view of the fins of the finned tube heat exchanger according to the third embodiment of the present invention, and FIGS. 7 (b), (c) and (d) are respectively shown in FIG. 7 (a). A-A sectional view, BB sectional view, partially enlarged view of FIG. 7A, FIG. 8 is an explanatory view of the drainage action of the fin of the fin tube heat exchanger, FIG. 9 is the fin tube heat exchange 10 (a) is a partial plan view of the fin of the fin tube heat exchanger, and FIGS. 10 (b) and 10 (c) are views of the fins in FIG. 10 (a), respectively. AA sectional view, BB sectional view, and FIG. 11 are explanatory views of drainage action when fins of the fin tube heat exchanger are formed in a corrugated shape.

  In addition, the same code | symbol is attached | subjected about the part similar to other embodiment, and the detailed description is abbreviate | omitted.

  The difference between the present embodiment and the other embodiments is that notches 9a and 9b as fluid paths are formed on the inclined surfaces 5a and 5b forming the convex portion 5, respectively, and the notches 9a and 9b are inclined. It is a point formed so as to extend in the direction in which the surfaces 5a and 5b are inclined.

  As shown in FIG. 7, the convex portion 5 is inclined toward the heat transfer tube 2 side with the ridgeline as a boundary, and is inclined toward the opposite side of the heat transfer tube 2, and is connected to the inclined portion 15. And the inclined surface 5b. Further, the cuts 9a and 9b shown in FIG. 7 are formed at two locations below and above the convex portion 5 with respect to the direction of gravity.

  Here, the width of the notches 9a and 9b is preferably about 0.05 mm to 0.5 mm so that water generated on the fins can be induced by capillary action.

  The lengths of the cuts 9a and 9b are not particularly limited. For example, the cut 9a is formed until the convex portion 5 and the pipe surrounding portion 4 are in contact with each other, and the cut 9b is a flat plate shape of the convex portion 5 and the fin 1. It may be formed until the part contacts. Further, the notch 9a and the notch 9b may be connected to each other at the ridge line of the convex portion 5 so as to be integrated.

  About the finned-tube heat exchanger comprised as mentioned above, the operation | movement and an effect | action are demonstrated below.

  As shown in FIG. 7D, the convex portion 5 formed on the fin 1 serves as a guide for the air flow S, and leaks the air flows Sa and Sb that circulate from the air flow S to the downstream portion of the heat transfer tube. The dead water area D can be reduced without attracting.

  Next, the drainage effect | action of the fin 1 at this time is demonstrated using FIG. FIG. 8 is arranged in time series from the left.

  As shown in FIG. 8 (left), particularly when the finned tube heat exchanger is used as an evaporator, condensed water 20 in which moisture in the air is condensed is generated around the heat transfer tube 2. Here, the inclined surface 5a and the inclined surface 5b are formed with a cut 9a and a cut 9b, respectively, so that the front and back of the fins communicate with each other and the inside and the outside of the convex portion 5 communicate with each other.

  Therefore, the condensed water 20 that has precipitated is guided to the outside of the convex portion 5 and to the back side of the fin 1 through the cuts 9a and 9b (in FIG. 8), and further to the gravity through the fin 1 It will be guided downward in the direction (right side of FIG. 8).

  Further, the condensed water 20 flowing along the surface of the fin 1 is also guided downward in the gravitational direction through the notches 9a and 9b formed above the convex portion 5.

As described above, the condensed water 20 can be smoothly guided downward in the gravitational direction of the fins 1 through the notches 9a and 9b, so that the drainage is improved without reducing the heat transfer area, A finned tube heat exchanger having excellent heat transfer performance can be provided.

  Further, when the notches 9a and 9b are formed perpendicular to the ridgeline of the convex portion 5, the heat conduction in the fin 1 spreads radially from the heat transfer tube as shown in FIG. The decrease can be suppressed.

  As shown in FIGS. 10A to 10C, the fin 1 has a mountain portion 13, a valley portion 14, and a valley portion 14 a with respect to the air flow S, a valley portion 14 a, a mountain portion 13, and a valley portion. 14, a peak portion 13, and a trough portion 14 a may be formed so as to be a wave-shaped M-shaped corrugated fin. Here, the peak portion 13, the valley portion 14, and the valley portion 14 a are formed by the inclined portion 15 that is inclined with respect to the air flow S.

  Further, as shown in FIG. 10A, the convex portion 5 has an inclined surface 5a inclined toward the heat transfer tube 2 side and an inclined surface inclined toward the opposite side of the heat transfer tube 2 with the ridge line as a boundary. 5b. Here, the convex part 5 and the inclination part 15 are connected via the inclined surface 5b.

  Thereby, as shown in FIG. 11, for example, when a finned tube heat exchanger is used as an evaporator, even if condensed water 20 is generated (left in FIG. 11), the condensed water 20 that has precipitated is cut into 9a. And it is guided to the outside of the convex portion 5 and the back side of the fin 1 through the notch 9b, and further to the peak portion 13 of the corrugated fin (which becomes a valley portion when viewed from the back side of the fin) (FIG. 11). The condensed water 20 is smoothly drained downward in the direction of gravity (right of FIG. 11).

  Thus, when the fin 1 is formed in a corrugated shape, a single fluid flow path through which water flows is formed by the notch 9 and the valley shape formed by the corrugated fin, so that the drainage can be further improved. .

  Further, when the fin 1 has a corrugated shape, as shown in FIG. 10 (b), the air flow is like a meandering air flow Sc, so that the temperature boundary layer can be made thin to promote heat transfer, The heat transfer performance of the heat exchanger can be improved.

  In FIG. 10, the fin 1 is formed as an M-shaped corrugated fin, but may be a V-shaped corrugated fin in which only one peak 13 is formed on the fin 1.

  Further, a plurality of cuts 9a and cuts 9b may be provided as shown in FIG. At this time, it is preferable to form radially from the center of the heat transfer tube 2 so that the ends of the cuts 9a and 9b on the opposite side of the heat transfer tube 2 are located outside the ridge line of the valley portion 14. Thereby, more condensed water 20 can be drained, and the heat transfer performance can be further improved.

  As described above, the finned tube heat exchanger according to the present invention improves the heat transfer performance of the wake portion of the heat transfer tube and improves the drainage of water generated on the surface of the fin. The present invention can be applied to a heat exchanger used for a hot water supply device, a heating device, or the like.

DESCRIPTION OF SYMBOLS 1 Fin 2 Heat transfer tube 4 Tube surrounding part 5 Convex part 5a 1st inclined surface 5b 2nd inclined surface 9, 9a, 9b Cutting (fluid path)
10 Small hole (fluid path)
13 Mountain part 14, 14a Valley part 15 Inclined part S, Sa, Sb, Sc Air flow G Gravity direction

Claims (2)

A plurality of fins, and a plurality of heat transfer tubes that pass through the plurality of fins and in which a fluid flows, and the fins include a tube peripheral portion formed around the heat transfer tubes, and the tube peripheral portion. The finned tube heat exchanger is characterized in that it has a convex portion formed so as to surround it, and a fluid path that communicates the front and back of the fin is provided in the convex portion. The fin includes an inclined portion that is inclined in a wave shape with respect to an air flow direction, and the convex portion is provided on a side opposite to the first inclined surface and the first inclined surface inclined to the heat transfer tube side. 2. The finned tube heat exchange according to claim 1, wherein the finned tube heat exchange is formed from an inclined second inclined surface, and the inclined portion and the convex portion are connected via the second inclined surface. vessel.