JP2014020582A - Fin tube type heat exchanger - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a fin tube type heat exchanger with an excellent heat transfer performance due to a cutting front edge effect.SOLUTION: The fin tube type heat exchanger comprises: plural heat transfer fins 10 almost parallely laminated at predetermined intervals; and plural heat transfer pipes (not shown) penetrating through the heat transfer fins 10 in a direction almost orthogonal to a plane direction of the heat transfer fins 10. Notches 13 are provided on the heat transfer fins 10 only in a stage direction almost orthogonal to a flow direction of gas. The heat transfer fin 10 on a windward side of the notch 13 on which the gas flows is protruded. A crest part 15 having an opening 14 formed by the notch 13 is provided on a leeward side. The heat transfer fin comprises a valley part 25 having a shape almost symmetrical to the crest part 15 with the notch 13 as an axis, and protruding in a direction opposite to the crest part 15 to be opened toward the windward side. The opening 14 by the notch 13 is enlarged, so as to increase a flow rate of gas penetrating through the heat transfer fin 10, promote mixture of the gas between top and back faces of the heat transfer fin 10, increase length of a front edge formed by the valley part 25, and improve a heat transfer performance by a larger front edge effect.

Description

  The present invention is used in air conditioners such as room air conditioners, packaged air conditioners, car air conditioners, etc., heat pump water heaters, refrigerators, freezers, etc., such as air flowing between a plurality of stacked flat plate heat transfer fins. The present invention relates to a finned tube heat exchanger that transfers heat between a gas and a fluid such as water or refrigerant flowing in a heat transfer tube.

  As a conventional fin tube type heat exchanger composed of a plurality of laminated plate-like heat transfer fins and heat transfer tubes, there are those shown in FIGS. 4 to 7 (for example, see Patent Document 1).

  FIG. 4 is a perspective view of a conventional fin tube heat exchanger described in Patent Document 1, FIG. 5 is a partial front view of heat transfer fins of the fin tube heat exchanger, and FIG. FIG. 7 is an enlarged perspective view of the main part of the heat transfer fin.

  4-7, the conventional fin tube type heat exchanger is laminated in parallel at a constant pitch, and a large number of plate-like heat transfer fins 101 through which a gas W such as air flows, and these The heat transfer fins 101 are inserted into the heat transfer fins 101 at a predetermined pitch at a predetermined pitch, and the heat transfer tubes 104 are configured such that the fluid R such as water or refrigerant flows therein. The heat transfer tubes 104 are the outer periphery of the through holes 11a of the heat transfer fins 101. It is tightly bonded to a cylindrical fin collar 102 raised vertically. Note that all the fin collars 102 extend in the same direction from the heat transfer fins 101 and have substantially the same height.

  Further, the slit forming portion 103 of the heat transfer fin 101 is provided with a cut 13 only in the step direction of the heat exchanger that is substantially perpendicular to the flow direction of the airflow 1, and the heat transfer fin on the windward side where the gas in the cut 13 flows. 101 is raised to the front side (the front side in FIG. 5, the upper side in FIG. 6), and a peak portion 15 having a substantially triangular opening 14 formed by a cut 13 is formed on the leeward side. A plurality of ridges 15 having leeward openings 14 are formed on the surfaces of the heat transfer fins 101 between the fin collars 102 adjacent in the step direction.

  When the gas flows along the mountain 15 and then passes through the opening 14 on the leeward side, a vertical vortex (not shown) is generated from which the temperature boundary layer on the surface of the heat transfer fin 101 on the leeward side is disturbed. Heat transfer is promoted by improving the heat transfer coefficient.

  At the same time, the heat transfer fins 101 are continuous in the step direction so that the heat conduction fins 101 are continuously cut in the step direction so that the heat conduction in the step direction of the heat transfer fins 101 is cut off and the region that does not contribute to heat transfer does not occur. Since the ridge portion 15 can be moved by heat conduction, the entire surface of the heat transfer fin 101 is configured to contribute to heat transfer and to improve heat transfer performance.

Japanese Patent No. 4775429

However, in the configuration of the conventional fin tube heat exchanger as described in Patent Document 1, when the flowing gas passes through the peak portion 15, a part of the gas is formed on the leeward side of the peak portion 15. The heat transfer fins 101 flow through the heat transfer fins 101 through the formed openings 14.
We expect improvement of heat transfer performance by mixing gas between the front and back, and improvement of heat transfer performance due to the leading edge effect by the downstream front edge of the cut 13, but the gas flow through the heat transfer fins 101 is There was a problem that it was a trace amount and a large improvement in heat transfer performance could not be obtained.

  The present invention solves the above-described conventional problems, and an object of the present invention is to provide a finned tube heat exchanger having improved performance due to a leading edge effect with a larger cut.

  In order to solve the above-described conventional problems, a finned tube heat exchanger according to the present invention includes a plurality of heat transfer fins stacked substantially in parallel at a predetermined interval, and a plane direction of the heat transfer fins. A plurality of heat transfer tubes penetrating the heat transfer fins in a direction orthogonal to each other, and a direction substantially orthogonal to the planar direction of the heat transfer fins around the through holes of the heat transfer fins through which the heat transfer tubes pass A substantially cylindrical fin collar extending to the heat transfer tube is inserted into the through hole in close contact with the fin collar, and flows in the plane direction of the heat transfer fin and the inside of the heat transfer tube. A finned tube heat exchanger configured to exchange heat with a thermal refrigerant, wherein the heat transfer fin is provided with a cut only in a step direction substantially perpendicular to the gas flow direction. The gas flows The heat transfer fin on the leeward side is raised, and a ridge part having an opening formed by the notch is provided on the leeward side. The ridge is substantially symmetric with the ridge part about the notch. It is provided with a trough that is raised in the opposite direction to the peak so as to open toward the front, and the vertical vortex generated when passing through the opening causes the heat transfer fin surface on the leeward side of the opening to The heat transfer fins are cut off and the heat transfer performance is reduced without interrupting the heat conduction of the heat transfer fins to reduce the heat transfer performance. Heat transfer performance can be obtained, and the opening by cutting is expanded more than before, so the flow rate of gas passing through the heat transfer fins increases, promoting mixing between the front and back of the fins, and forming by the valleys The length of the leading edge is increased than before It is, it is possible to improve the performance by a greater leading edge effect.

  Since the finned tube heat exchanger according to the present invention is configured as described above, when the gas flows along the mountain portion having the opening on the leeward side and passes through the opening on the leeward side, the vertical vortex From there, the temperature boundary layer on the surface of the heat transfer fin on the leeward side is disturbed to improve the heat transfer rate and promote heat transfer, and the heat conduction of the heat transfer fin is blocked by a triangular piece. The heat transfer fins can be thermally conducted without generating a region that does not contribute to heat transfer performance, and the heat transfer fins are continuous. Heat transfer performance can be obtained, and the opening by cutting is expanded more than before, so the flow rate of gas passing through the heat transfer fin is increased, and mixing between the heat transfer fin front and back is promoted. The length of the leading edge formed by It is possible to provide a finned tube heat exchanger having improved performance due to the large leading edge effect.

The front view of the heat-transfer fin of the fin tube type heat exchanger in Embodiment 1 of this invention Bottom view of the heat transfer fin Enlarged perspective view of the main part of the heat transfer fin A perspective view of a conventional finned tube heat exchanger Partial front view of heat transfer fin of the finned tube heat exchanger Bottom view of the heat transfer fin Enlarged perspective view of the main part of the heat transfer fin

  The first invention includes a plurality of heat transfer fins stacked substantially in parallel at a predetermined interval, and a plurality of heat transfer tubes penetrating the heat transfer fins in a direction substantially perpendicular to the planar direction of the heat transfer fins. A substantially cylindrical fin collar extending in a direction substantially perpendicular to the plane direction of the heat transfer fin is formed around a through hole of the heat transfer fin through which the heat transfer tube passes. A fin tube type inserted into the through hole in close contact with the fin collar to exchange heat between the gas flowing in the plane direction of the heat transfer fin and the thermal refrigerant flowing inside the heat transfer tube A heat exchanger, wherein the heat transfer fin is provided with a cut only in a step direction that is substantially perpendicular to the flow direction of the gas, and the heat transfer fin on the windward side where the gas of the cut flows is raised. , Notch on the leeward side A trough that has a crest having an opening that is formed, has a shape that is substantially symmetrical to the crest with the notch as an axis, and is raised in a direction opposite to the crest so as to open toward the windward side The vertical vortex generated when passing through the opening promotes heat transfer on the surface of the heat transfer fin on the leeward side of the opening, and cuts off the heat conduction of the heat transfer fin. The heat transfer performance is not reduced by generating a region that does not contribute to heat, the entire heat transfer fin surface contributes to heat transfer, and excellent heat transfer performance can be obtained. Because the flow rate of the gas passing through the heat transfer fins is increased, mixing between the heat transfer fins front and back is promoted, and the length of the leading edge formed by the valleys is increased compared to the conventional case. Improve performance with a larger leading edge effect It can be.

  In the second invention, in particular, the shape of the opening of the first invention is a shape in which two substantially triangular shapes with the plane of the heat transfer fin as an axis of symmetry are arranged. After flowing along, a vertical vortex is generated when passing through the opening on the leeward side, and heat transfer can be promoted by disturbing the temperature boundary layer on the leeward side to improve the heat transfer coefficient. On the other hand, the heat conduction fins are continuous in the step direction without causing heat transfer performance to deteriorate by generating a region that does not contribute to heat transfer by blocking the heat conduction in the step direction of the heat transfer fins. Since the part can conduct heat, the entire heat transfer fin surface can contribute to heat transfer, and excellent heat transfer performance can be obtained.

  In addition, since the opening by cutting is larger than the conventional one, the flow rate of the gas passing through the heat transfer fins is increased, the mixing between the heat transfer fins front and back is promoted, and the length of the front edge formed by the valleys is increased. As a result, the performance can be improved by a larger leading edge effect.

  In the third invention, in particular, the shape of the opening of the first invention is a shape in which two substantially trapezoidal shapes with the surface of the heat transfer fin as an axis of symmetry are arranged. After flowing along, a vertical vortex is generated when passing through the opening on the leeward side, and heat transfer can be promoted by disturbing the temperature boundary layer on the leeward side to improve the heat transfer coefficient. On the other hand, the heat conduction fins are continuous in the step direction without causing heat transfer performance to deteriorate by generating a region that does not contribute to heat transfer by blocking the heat conduction in the step direction of the heat transfer fins. Since the part can conduct heat, the entire heat transfer fin surface can contribute to heat transfer, and excellent heat transfer performance can be obtained. In addition, since the four slopes forming the peak and valley are connected to the flat ridge at a gentle angle, the process of raising the peak is easy.

  In addition, since the opening by cutting is larger than the conventional one, the flow rate of the gas passing through the heat transfer fins is increased, the mixing between the heat transfer fins front and back is promoted, and the length of the front edge formed by the valleys is increased. As a result, the performance can be improved by a larger leading edge effect.

In the fourth invention, in particular, the shape of the opening of the first invention is a shape in which two substantially circular arcs with the plane of the heat transfer fin as an axis of symmetry are arranged. After flowing along, a vertical vortex is generated when passing through the opening on the leeward side, and heat transfer can be promoted by disturbing the temperature boundary layer on the leeward side to improve the heat transfer coefficient. On the other hand, the heat conduction fins are continuous in the step direction without causing heat transfer performance to deteriorate by generating a region that does not contribute to heat transfer by blocking the heat conduction in the step direction of the heat transfer fins. Since the part can be thermally conducted, the entire heat transfer fin surface can contribute to heat transfer, and excellent heat transfer performance can be obtained. Moreover, since the peak portion is raised with an arc cross section, it is easy to process.

  In addition, since the opening by cutting is larger than the conventional one, the flow rate of the gas passing through the heat transfer fins is increased, the mixing between the heat transfer fins front and back is promoted, and the length of the front edge formed by the valleys is increased. As a result, the performance can be improved by a larger leading edge effect.

  Hereinafter, embodiments of the finned tube heat exchanger 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)
1 is a front view of a heat transfer fin of a finned tube heat exchanger according to Embodiment 1 of the present invention, FIG. 2 is a bottom view of the heat transfer fin, and FIG. 3 is a main portion of the heat transfer fin. It is an expansion perspective view. In addition, the same code | symbol is attached | subjected to the same part as the said conventional fin tube type heat exchanger, and the detailed description is abbreviate | omitted.

  As shown in FIGS. 1 and 2, each heat transfer fin 10 of the finned tube heat exchanger in the present embodiment has a plurality of through holes 11a (two through holes in FIG. 1) through which the heat transfer tube 12 passes. Only the holes are shown). Around each through-hole 11a, a substantially cylindrical fin collar 11 extending in a direction substantially perpendicular to the plane direction of the heat transfer fin 10 or the flow direction of the airflow 1 is formed. For example, each heat transfer tube By expanding the diameter of the heat transfer tube 12, the heat transfer tube 12 is inserted into the through hole 11 a while being in close contact with the fin collar 11. Note that all the fin collars 11 extend from the heat transfer fins 10 in the same direction and have substantially the same height.

  Here, the diameter expansion of the heat transfer tube 12 will be described in detail. When manufacturing the fin tube type heat exchanger, the heat transfer fins 10 are stacked and the heat transfer tube 12 is inserted into the fin collar 11, but the workability is good. Therefore, the inner diameter of the fin collar 11 at the time of fin pressing is processed somewhat larger than the outer diameter of the heat transfer tube 12. However, after the heat transfer tube 12 is inserted into the fin collar 11, the heat transfer tube 12 is expanded in diameter using a hydraulic pressure or by a mechanical method, and the heat transfer tube 12 and the fin collar 11 are brought into close contact with each other to perform heat transfer performance. Has improved.

  1 to 3, the heat transfer fin 10 is provided with a cut 13 only in the step direction of the heat exchanger that is substantially perpendicular to the flow direction of the airflow 1, and the heat transfer on the windward side where the gas in the cut 13 flows. The fin 10 is raised on the front side (the front side in FIG. 1, the upper side in FIG. 2), and a peak portion 15 having an opening 14 formed by a cut 13 is formed on the leeward side.

  Further, the ridges are raised on the back side of the heat transfer fins 10 (the back side in FIG. 1, the bottom side in FIG. 2) with respect to the ridges 15 so as to form a shape symmetrical to the ridges 15 with the notch 13 as the axis of symmetry. 15 is provided with a valley portion 25 that shares the substantially rhombus-shaped opening 14 on the leeward side. A plurality of peak portions 15 and valley portions 25 are formed on the surface of the heat transfer fin 10 between the fin collars 11 adjacent in the step direction.

  The peak 15 is not limited to be formed by raising the front side and the valley 25 is raised on the back side, and the peak 15 may be formed on the back side and the valley 25 may be raised on the front side. A front ridge and a back ridge may be mixed.

  The operation and action of the fin tube heat exchanger according to the present embodiment configured as described above will be described below.

  Cuts 13 are provided in the heat transfer fins 10 in a step direction substantially perpendicular to the gas flow direction, and the heat transfer fins 10 on the windward side of the airflow 1 in the cuts 13 are raised to form openings formed by the cuts 13 on the leeward side. Since the mountain portion 15 having the portion 14 is formed, the gas flows along the mountain portion 15 and then a vertical vortex is generated when passing through the opening portion 14 on the leeward side, from which the heat transfer fin 10 on the leeward side is formed. Heat transfer is promoted by disturbing the surface temperature boundary layer and improving the heat transfer coefficient.

  Further, the ridge portion 15 is raised to the back side of the heat transfer fin 10 so as to form a shape symmetrical to the ridge portion 15 with the notch 13 as the axis of symmetry, and an opening portion 14 having a substantially rhombus shape is formed on the leeward side of the ridge portion 15. Since the valley portion 25 shared on the windward side is formed, a part of the gas flows along the back side surface of the mountain portion 15, and then flows along the front side surface of the valley portion 25 through the opening portion 14. Since it mixes between the front and back of the heat-transfer fin 10, heat-transfer performance can be improved.

  The opening 14 is obtained by increasing the amount of gas mixed between the front and back of the heat transfer fin 10 because the valley portion 25 is raised from the back surface of the heat transfer fin 10 so as to be larger than before. The improvement in heat transfer performance has increased compared to the conventional case.

  Further, the heat transfer performance can be improved by the leading edge effect of the temperature boundary layer at the leeward side of the notch 13 and the leading edge 26 of the valley 25. Since the front edge 26 of the valley portion 25 is raised from the back side surface of the heat transfer fin 10 through the valley portion 25 and is longer than before, the obtained front edge effect is also improved compared to the conventional case.

  In addition, the notch 13 for forming the peak portion 15 and the valley portion 25 is only in the step direction so that the heat conduction in the step direction of the heat transfer fins 10 is blocked and a region that does not contribute to heat transfer does not occur. Since heat can be transferred by heat conduction through the ridges 15 and the valleys 25 where the heat transfer fins 10 are continuous in the step direction, the entire surface of the heat transfer fins 10 contributes to heat transfer and is excellent in heat transfer. Thermal performance can be obtained.

  If the shape of the opening 14 is formed by arranging two substantially trapezoidal shapes that are symmetrical with respect to the surface of the heat transfer fin 10, the four slopes that form the peak 15 and the valley 25 are loosely formed on a flat ridge. Since the connection is made at a proper angle, it is possible to facilitate the processing of raising the peak portion 15 and the valley portion 25. Furthermore, if the shape of the opening 14 is formed by arranging two substantially circular arcs with the heat transfer fin 10 surface as the axis of symmetry, the cross-sections of the crests 15 and troughs 25 are raised in a circular arc shape. Can be made easier.

  The finned tube heat exchanger according to the present invention is provided with a notch in a heat transfer fin, and a heat transfer fin portion on the windward side of the notch is raised to form a peak portion having an opening formed on the leeward side by the notch. As a result, the vertical vortex generated when passing through the opening on the leeward side promotes heat transfer on the surface of the heat transfer fin on the leeward side, and blocks the heat conduction of the heat transfer fin and does not contribute to heat transfer. The heat transfer performance is not reduced by generating a region, the entire heat transfer fin surface contributes to heat transfer, excellent heat transfer performance can be obtained, and the opening by cutting is expanded more than before. As a result, the flow rate of the gas through the heat transfer fins is increased, mixing between the heat transfer fins is promoted, and the length of the leading edge formed by the valleys is increased compared to the conventional one, resulting in a larger leading edge effect. To improve performance Since it, the air conditioner, heat pump water heater, is useful refrigerator, as a heat exchanger used in the freezer or the like.

10, 101 Heat transfer fin 11, 102 Fin collar 11a Through hole 12, 104 Heat transfer tube 13 Notch 14 Opening portion 15 Mountain portion 25 Valley portion 26 Leading edge

Claims (4)

A plurality of heat transfer fins stacked substantially in parallel with a predetermined interval; and a plurality of heat transfer tubes penetrating the heat transfer fins in a direction substantially orthogonal to a planar direction of the heat transfer fins, the heat transfer tubes A substantially cylindrical fin collar extending in a direction substantially orthogonal to the planar direction of the heat transfer fin is formed around the through hole of the heat transfer fin through which the heat transfer fin passes, and the heat transfer tube is in close contact with the fin collar A fin-tube heat exchanger that is inserted into the through-hole in a state in which the heat transfer fins perform heat exchange between the gas flowing in the planar direction of the heat transfer fins and the thermal refrigerant flowing through the heat transfer tubes. The heat transfer fin is provided with a cut only in a step direction which is substantially perpendicular to the gas flow direction, and the heat transfer fin on the windward side where the gas flows in the cut is raised so that the cut is made on the leeward side. Formed by A crest having an opening, having a shape substantially symmetrical to the crest with the notch as an axis, and having a trough raised in the opposite direction to the crest so as to open toward the windward side A finned tube heat exchanger. The fin tube type heat exchanger according to claim 1, wherein the shape of the opening is a shape in which two substantially triangular shapes with the plane of the heat transfer fin as an axis of symmetry are arranged. The fin tube type heat exchanger according to claim 1, wherein the shape of the opening is a shape in which two substantially trapezoidal shapes with the surface of the heat transfer fin as an axis of symmetry are arranged. 2. The finned tube heat exchanger according to claim 1, wherein the shape of the opening is a shape in which two substantially circular arcs with the plane of the heat transfer fin as an axis of symmetry are arranged.

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