JP2013231521A - Fin tube type heat exchanger - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a fin tube type heat exchanger having improved drainability.SOLUTION: A fin tube type heat exchanger includes a plurality of fins 1 with a rising piece 4 where an airflow 100 passes, and a plurality of heat transfer pipes 2 passing through the fins 1 and allowing a fluid to flow therein. The rising piece 4 is arranged only on the downstream of the center of the adjoining heat transfer pipes 2 in a direction of the airflow 100. The rising piece 4 is formed to tilt in the direction of the airflow. Fluid paths (7a, 7b, 7c, 7d) are provided on a fin plane part 1c with the rising piece 4. Drainability can be improved by smoothly flowing down moisture accumulated in the rising piece 4 and moisture precipitated on the fins 1.

Description

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

  Conventionally, as shown in FIG. 8, this type of fin tube type heat exchanger is composed of fins 1 arranged at a predetermined interval Fp and heat transfer tubes 2 inserted through the fins 1 at a substantially right angle and penetrating therethrough. ing.

  FIG. 9A is a cross-sectional view when the fins constituting the conventional fin tube heat exchanger are stacked, and FIG. 9B is a partial plan view of the fins constituting the conventional fin tube heat exchanger.

  As shown in FIG. 9, a fin collar 3 raised from the surface of the fin 1 is formed on the fin 1, and the heat transfer tube 2 is inserted into the fin collar 3. The fin collar 3 plays a role in which the end face 30 is in contact with the adjacent fins 1 and maintains the distance between the fins 1 at a predetermined distance.

  In the heat exchanger, an air flow 100 (for example, air) introduced by a blower (not shown) or the like flows through the gaps between the stacked fins 1 and flows through the heat transfer tubes 2 through the fins 1. Heat exchange with a fluid (for example, R410a, a refrigerant such as carbon dioxide).

  The fluid flowing through the heat transfer tube 2 is generally in a two-phase state of a liquid phase and a gas phase, and the liquid phase evaporates due to heat exchange with the airflow 100 to become a superheated gas. Out of heat exchanger.

  Among such fin tube heat exchangers, there are those in which cuts and ridges are formed over the entire area of the fins in order to promote heat transfer according to the pursuit of high efficiency (for example, see Patent Documents 1 and 2).

  FIGS. 10A and 10B show a cross-sectional view and a partial plan view, respectively, when fins are stacked in the fin tube heat exchanger described in Patent Document 1. FIG.

  The cut and raised 4 shown in FIG. 10 has a louver shape in which a part of the fin 1 is bent in a substantially vertical direction with respect to the fin plane portion 1c. The cut and raised 4 is formed on the fin 1 so as to be inclined in a straight line from the upstream side to the downstream side of the airflow 100, thereby reducing the dead water area downstream of the heat transfer tube 2.

  Moreover, Fig.11 (a) and (b) show sectional drawing at the time of laminating | stacking a fin in the fin tube heat exchanger of patent document 2, and a partial top view, respectively.

  The cut-and-raised part 4 shown in FIG. 11 has a slit-like shape in which the plane is offset so as to be substantially parallel to the fin plane part 1c and both ends are connected to and supported by the fin plane part 1c. This cut and raised 4 is formed on both the upstream side and the downstream side of the heat transfer tube 2 with respect to the air flow 100, and the height of the cut and raised 4 is set within a predetermined range so that the remarkable transfer performance generated at the time of frost formation. We are trying to suppress the decline of

JP 2008-89237 A JP 11-125495 A

  However, in the conventional configuration, when moisture is deposited on the fin, the moisture stays in the cut and does not flow smoothly, and increases the airflow resistance, thereby reducing the heat transfer performance. It had the problem that.

  Moreover, the water | moisture content which flows into the plane part of a fin cannot be made to flow down smoothly, but it had the subject that heat-transfer performance fell by reducing the heat-transfer area of a fin.

  An object of the present invention is to solve the above-mentioned conventional problems, and to provide a finned tube heat exchanger having excellent heat transfer performance by smoothly draining water deposited on fins to improve drainage. To do.

  In order to solve the conventional problem, a finned tube heat exchanger according to the present invention has a plurality of fins that have cuts and ridges, through which airflow passes, and through which the fluid flows. A heat transfer tube, and the cut-and-raised portion is disposed only downstream from the center of the adjacent heat-transfer tube with respect to the airflow direction, and the cut-and-raised portion is directed to the airflow direction. It is formed so as to be inclined, and a fluid path is provided on a fin plane portion on which the cut and raised portions are disposed.

  As a result, the water adhering to the cut and raised flows down along the inclination of the cut and raised, and the water retained in the cut and the moisture on the fin flat part are gravity-induced by the fluid path formed in the fin flat portion. Drainability can be improved by guiding downward in the direction.

  According to the present invention, it is possible to provide a finned tube heat exchanger with improved drainage and excellent heat transfer performance.

(A) Sectional view when the fins of the fin tube heat exchanger according to Embodiment 1 of the present invention are stacked (b) Partial plan view of the fins of the fin tube heat exchanger according to Embodiment 1 of the present invention Sectional drawing which shows cut-and-raised height Hs and corrugated height Hw in the fin of the same finned-tube heat exchanger Sectional drawing which shows cut-and-raised height Hs and fin collar height Hc in the fin of the same finned-tube heat exchanger Explanation of drainage action in fins of the finned tube heat exchanger (A) Sectional view when laminating fins with different shapes of the fin tube heat exchanger (b) Partial plan view of fins with different shapes of the fin tube heat exchanger Partial plan view of the fin showing the shape of another fluid path in the finned tube heat exchanger (A) Sectional view when laminating fins with different shapes of the fin tube heat exchanger (b) Partial plan view of fins with different shapes of the fin tube heat exchanger Configuration diagram of conventional fin tube heat exchanger (A) Sectional view when laminating fins of conventional fin tube heat exchanger (b) Partial plan view of fins of conventional fin tube heat exchanger (A) Sectional view when laminating different shape fins of conventional fin tube heat exchanger (b) Partial plan view of another shape fin of conventional fin tube heat exchanger (A) Sectional view when laminating different shape fins of conventional fin tube heat exchanger (b) Partial plan view of another shape fin of conventional fin tube heat exchanger

  A first invention includes a plurality of fins having a cut and raised, through which an air flow passes, and a plurality of heat transfer tubes that pass through the fin and in which a fluid flows. The cut and raised includes the air flow Is arranged only on the downstream side of the center of the adjacent heat transfer tube with respect to the direction, and the cut and raised are formed so as to be inclined with respect to the air flow direction. It is a fin tube heat exchanger characterized by providing a fluid path on the arranged fin plane part.

  As a result, the moisture adhering to the cut and raised flows down along the inclination of the cut and raised, and the water accumulated on the cut and raised and the moisture on the fin flat portion by the fluid path cut formed in the fin flat portion. Can be guided downward in the direction of gravity, so that drainage can be improved and heat transfer performance can be improved.

  In a second aspect of the invention, in particular, in the first aspect of the invention, the cut and raised portion is formed in a slit shape having two rising sides, and the width direction of the rising side is formed in parallel to the direction of gravity. It is the fin tube heat exchanger characterized by the above-mentioned.

  As a result, the water that has reached the rising edge of the cut and rise flows down by its own weight along the rising edge formed in parallel to the direction of gravity, so that the water remaining on the fins is reduced and the frost resistance is increased. And drainage can be improved.

  In a third aspect of the present invention, in particular, in the second aspect of the present invention, the fluid path is a fin tube heat exchanger characterized in that the fluid path is a notch whose one end is a contact point between the rising side and the fin plane portion.

  Thereby, since the water | moisture content which is easy to stay especially in the rising edge of a cut and raised is smoothly induced | guided | derived to the gravitational direction downward via a simple cutting, a drainage property can be improved more.

  According to a fourth aspect of the present invention, in particular, in the second or third aspect of the invention, the fluid path is constituted by a cut, and the cut is formed on the cut and raised, and the fin tube heat exchange is characterized in that It is a vessel.

  Thereby, especially in the case where the whole cut and raised water is captured, water is guided and flows down by a simple cutting process, so that the drainage 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)
The heat exchanger according to the first embodiment of the present invention is configured as shown in FIG. 8, similarly to the conventional heat exchanger. Here, the case where it is used as an evaporator will be described below as an example.

FIGS. 1A and 1B show a cross-sectional view and a partial plan view of fins constituting the heat exchanger according to the present embodiment. In FIG. 1, reference numeral 4 denotes a part of the fin plane portion 1 c that is offset in a slit shape, 5 denotes a wave shape (generally also referred to as a corrugate or waffle), and 6 denotes an airflow 100 around the fin collar 3. It is the seat part provided in order to guide.

  The slit-like cut-and-raised 4 is inclined so as to be inclined in the flow direction of the airflow 100, and the windward side is arranged vertically (in the direction of gravity). 4 a is cut and not continuous with the fin plane portion 1 c, and two rising edges 4 b are connected to the fin plane portion 1 c to cut up and support 4.

  Thereby, the cut-and-raised opening 4c through which condensed drain water flows or the airflow 100 passes is formed vertically above and below the cut-and-raised 4. The rising edge 4b is formed so that the width direction is parallel to the gravity direction among the thickness direction and the width direction.

  Further, when the windward side is defined as the fin wind upper part 1a and the fin wind lower part 1b on the leeward side with respect to the flow direction of the air flow 100 with the line segment L connecting the centers of the heat transfer tubes 2 separated, it is cut and raised 4 Are disposed only in the fin lee 1b, and the corrugations 5 are disposed in the fin lee 1a and the fin lee 1b. However, the cut-and-raised part 4 is disposed on the fin plane part 1 c outside the seat part 6.

  Further, a notch 7a and a notch 7b are formed from the contact point between the rising edge 4b and the fin plane portion 1c as a fluid path starting from the contact point. Here, the cut 7 a is formed on the leeward side of the airflow 100 of the cut and raised portion 4, and the cut 7 b is formed on the upwind side of the airflow 100 of the cut and raised portion 4.

  The cut 7a shown in FIG. 1 is formed so as to be inclined so that one end on the upstream side is positioned above the vertical (gravity) direction with respect to the direction of the airflow 100. Further, the cut 7b shown in FIG. 1 is formed in parallel to the direction of gravity. The fin 1 shown in FIG. 1 has a wave shape 5 formed on the surface thereof, and the cuts 7 b are formed in parallel along the valley line 10 formed by the wave shape 5.

  Here, when the widths of the cuts 7a and 7b are, for example, about 0.05 mm to 0.5 mm, the capillary phenomenon is satisfactorily generated, and moisture can be smoothly induced, so that the drainage is further improved. Can do.

  In addition to the notch, the shape of the fluid path is such that the front and back of the fins communicate with each other and capillarity occurs so that moisture can be induced. For example, moisture can be induced by a small hole having a diameter of about 0.05 mm to 0.5 mm.

  Here, as shown in FIGS. 2 and 3, the height of the fin collar 3 is Hc (for example, 1.5 mm), the height of the cut-and-raised 4 is Hs (for example, 0.75 mm), and the height of the wave shape is high. When the height is Hw (for example, 1 mm), each height is formed so as to satisfy the relationship of Hc> Hw> Hs. Furthermore, all the cut-ups 4 are formed by being cut and raised perpendicularly to the fin plane portion 1c in the same direction.

  The operation and action of the heat exchanger configured as described above will be described below.

  The heat exchanger in the present embodiment operates so as to promote turbulence by meandering the airflow 100 passing through the gap between the fins in the fin wind upper portion 1 a formed in the wave shape 5. Furthermore, in the fin wind lower part 1b, it operates so that the temperature boundary layer may be re-formed at the cut-and-raised end 4a by allowing the air flow 100 to pass through the cut-and-raised part 4.

  In general, the cut and raised 4 has a high heat transfer promoting effect. Thus, by arranging the wave shape 5 and the cut and raised 4 in this way, the heat transfer of the fin lee 1b having a low heat flow rate is further strengthened. It promotes and acts so that the heat flow velocity of the fin wind upper part 1a and the fin wind lower part 1b becomes relatively uniform.

  In particular, when the fin temperature is less than 0 ° C. and the heat exchanger is operated under operating conditions with frost formation, frost formation on the fin wind lower portion 1b is generated and accelerated by 4, and the fin wind It acts so that the frost formation on the upper part 1a and the fin wind lower part 1b is relatively uniform, and the frost resistance can be improved.

  Further, as shown in FIG. 2, by making the height Hw of the waveform 5 higher than the height Hs of the waveform 4, the air flow 100 guided by the waveform 5 is generated by the generation 4 and surely passes. It operates so that the heat transfer promotion effect in the cut and raised 4 can be obtained more strongly.

  Further, since the cut and raised 4 is formed in the same direction as the fin collar 3 from the fin flat surface portion 1c, the air current 100 generates a vortex in the vicinity of the cut and raised 4, and the air flow 100 meanders more than necessary. It operates so as not to let the air flow increase, and acts to suppress the influence of the ventilation resistance increase due to the cut and raised 4 to a small extent.

  In addition, since the cut and raised opening 4c opens toward the substantially vertical upper side and the substantially vertical lower side, and is further inclined and shaped so that the windward side is vertically upward toward the flow direction of the airflow 100, In addition to its own weight, the kinetic energy of the airflow 100 acts on the drain water adhering to the cut and raised 4 in the direction in which the drain water flows down.

  Furthermore, as shown in FIG. 4, the drain water generated between the fin plane part 1 c and the cut and raised 4 is retained by the notch 7 a starting from the contact point between the rising edge 4 b and the fin plane part 1 c. It operates so that water flows down smoothly against the surface tension and the amount of water retention in the fin 1 is reduced.

  Thereby, the drainage of drain water improves on the driving | running condition that drain water adheres to the fin 1, and it acts so that the ventilation resistance of a heat exchanger may be made small.

  In the present embodiment, as shown in FIG. 1, the notch 7 a is formed so as to be inclined so that the upper end portion thereof is located on the upstream side with respect to the air flow 100. In the notch 7a formed below the shim 4, water flowing through the fin flat surface portion 1c can be guided toward the outside of the fin 1 as shown in FIG. Can be made.

  Further, with respect to the cut 7 a formed above the cut and raised portion 4, the water staying above the cut and raised portion 4 and the water deposited on the fin plane portion 1 c are guided toward the outside of the fin 1. be able to.

  In addition, the notch 7b starting from the contact point between the rising edge 4b and the fin flat surface portion 1c causes water against the surface tension that is generated between the fin flat surface portion 1c and the cut and raised portion 4 to retain the drain water. The water flowing in the vicinity of the center of the fin 1 can be smoothly guided.

  In the present embodiment, the notch 7 b is formed along the wave shape 5, so that one flow path is formed for the water flowing in the vicinity of the center of the fin 1 and deposited on the fin 1. Moisture can be smoothly induced.

  In particular, when the temperature of the fin is less than 0 ° C. and the operation is performed under operating conditions where the heat exchanger has frost formation, the melted water generated by the frost melting at the time of defrosting causes the slope of 4 to rise. Since it flows down smoothly using the cut 7a and the cut 7b, it acts to suppress an increase in ventilation resistance due to re-freezing of the molten water retained in the fin 1 when defrosting is restored.

  Further, as shown in FIG. 3, by making the height Hc of the fin collar 3 higher than the height Hs of the cut and raised 4, the adjacent fin plane portion 1 c and the cut and raised 4 may come into contact with each other. No operation is performed so as to reduce the retention amount of drain water due to the surface tension of the fins 1.

  Thereby, the drainage of drain water improves on the driving | running condition that drain water adheres to the fin 1, and it acts so that the ventilation resistance of a heat exchanger may be made small.

  In addition, since the cut and raised 4 is disposed outside the seat portion 6, a predetermined interval can be provided between the cut and raised 4 and the fin collar 3, so that the drain adhered to the cut and raised 4 The water does not stay with the fin collar 3 due to the surface tension and operates so as to flow downward substantially vertically.

  Therefore, under the operating conditions where the drain water adheres to the fins 1, the drainage of the drain water is improved, and the air resistance of the heat exchanger is reduced.

  In addition, when the seat part 6 and the fin plane part 1c are formed in the same plane shape, the length formed between the contacts 20 of the corrugated shape 5 and the seat part 6 is a distance D, and the distance D is a diameter. The circular region is defined as a seat portion 6 and the outside thereof as a fin plane portion 1c.

  As described above, in the present embodiment, the cut-and-raised part 4 that is inclined toward the airflow direction is provided, and the rising edge 4b is formed on the fin plane portion 1c on which the cut-and-raised part 4 is formed. A notch 7a and a notch 7b are provided starting from a contact point with the fin plane portion 1c.

  As a result, the drain water adhering to the cut and raised portion 4 can be smoothly guided and flowed down by the cuts 7a and 7b that are easy to process, so that drainage drainage is improved and ventilation resistance is reduced. Therefore, the heat exchange capability can be improved.

  Here, although the direction in which the cut and raised 4 and the fin collar 3 are formed is the same, the cut and raised 4 that is cut and raised in the direction opposite to the fin collar 3 may be included.

  The shape of the cut-and-raised 4 is not limited to that of the fin 1 as shown in FIGS. 5 (a) and 5 (b), except that the fin 1 is partially offset in the slit shape as shown in FIG. The portion may be cut and bent so as to be substantially perpendicular to the fin plane portion 1c. In this case, the starting ends of the notches 7a and 7b can be contact points between the cut and raised openings 4c and the places where the raised portions 4 rise and the fin plane portion 1c.

  As shown in FIG. 6, the notch 4 is captured by the notch 7c by the notch 7c as the fluid path starting from the notch opening 4c and the notch 7e as the fluid path formed on the notch 4. Moistened water can be guided downward in the gravitational direction, and is deposited on the fin 1 by a cut 7d as a fluid path formed on the fin plane portion 1c and not connected to the cut and raised portion 4. Since water can be smoothly guided downward in the direction of gravity, drainage can be further improved.

  In addition, as shown in FIG. 7, the cut and raised 4 is disposed so as to be inclined so that the leeward side is substantially vertically upward toward the flow direction of the air flow 100, and such a cut and raised 4 is formed. A cut (not shown) may be formed in the fin plane portion 1c.

  Further, as shown in FIG. 1, when the wave shape 5 is formed not only on the upstream side but also on the downstream side with respect to the flow direction of the air flow 100, the temperature boundary layer on the surface of the fin 1 is disturbed. Since the thickness is reduced and heat transfer is promoted, the heat exchange capacity can be further increased while maintaining frost resistance and drainage.

  With the above-described configuration, for example, at the time of defrosting, it is possible to smoothly flow down the melted water generated by melting the frost using the inclination of the cut and raised 4 and the fluid path. Since the molten water can flow downward in the direction of gravity due to the ridges and valleys, the retention of the molten water in the fin 1 is reduced, and the ventilation resistance is increased by re-freezing the molten water after defrosting is restored. Can be suppressed.

  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.

  As described above, the finned tube heat exchanger according to the present invention is formed only on the downstream side of the fin with respect to the airflow direction, and is formed on the fin flat surface portion and the cut and raised portions inclined with respect to the airflow direction. Since the drainage can be improved by the fluid path, it can be applied to a heat exchanger used in an air conditioner, a hot water supply device, a heating device, or the like.

DESCRIPTION OF SYMBOLS 1 Fin 1a Fin wind upper part 1b Fin wind lower part 1c Fin plane part 2 Heat transfer tube 3 Fin collar 4 Cut-and-raise 4a Cut-and-raised end part 4b Rising edge 4c Cut-and-raised opening part 5 Wave shape 6 Seat part 7a Cut (fluid path) )
7b notch (fluid path)
7c notch (fluid path)
7d notch (fluid path)
7e notch (fluid path)
100 Airflow

Claims (4)

A plurality of fins having a cut and raised, and a plurality of fins through which the airflow passes, and a plurality of heat transfer tubes that pass through the fin and in which the fluid flows, and the cut and raised are adjacent to the airflow direction. The fin plane portion provided only on the downstream side of the center of the matching heat transfer tube, and the cut and raised portions are inclined with respect to the airflow direction, and the cut and raised portions are provided. A finned tube heat exchanger characterized in that a fluid path is provided thereon. 2. The fin according to claim 1, wherein the cut and raised are formed in a slit shape having two rising edges, and the width direction of the rising edges is formed in parallel to the direction of gravity. Tube heat exchanger. The fin tube heat exchanger according to claim 2, wherein the fluid path is a cut having a contact point between the rising side and the fin plane portion as one end. 4. The finned tube heat exchanger according to claim 2, wherein the fluid path is formed by a cut, and the cut is formed on the cut and raised portion. 5.