TW201530077A - Heat transfer tube for heat exchanger and heat exchanger - Google Patents

Abstract

To provide a heat transfer tube for a heat exchanger, which enables the heat exchanger to have a compact construction. A heat transfer tube (11) for a heat exchanger is provided with: an outer tube (13); multiple inner tubes (15) inserted through the outer tube (13) so that the axes of the inner tubes are arranged with an equal distance from one to the other in a cross section orthogonal to the axes; a first coil (17) having at least a portion thereof fixed on an inner circumferential surface (21) of the outer tube, said multiple inner tubes (15) being inserted through the first coil (17); second coils (19) each having at least a portion thereof fixed on an inner circumferential surface (23) of each inner tube; a flow path cross-section area (S1) of a first flow path (25) defined by the inside of the outer tube (13) and the outsides of the inner tubes (15); and a flow path cross section area (S2) of second flow paths (27), defined by a total area of flow path cross sections of the inner tubes (15) and having a ratio with the flow path cross section (S1) such that S1:S2 = 1:2 to 2:1.

Description

Heat transfer tube and heat exchanger for heat exchanger

The present invention relates to a double-tube heat exchanger for a heat exchanger having an outer tube and an inner tube, and a heat exchanger using the same.

As a well-known heat transfer tube for a heat exchanger, an inner tube is inserted into the outer tube for heat exchange between a fluid flowing in the inner tube and a fluid flowing between the inner tube and the outer tube. A heat transfer tube for a double-tube type heat exchanger (for example, see Patent Document 1). A double-casing type heat exchanger disclosed in the same document is provided with a heat transfer promoting body for dividing the inner flow path of the outer tube into a spiral shape between the inner tube and the outer tube. The heat transfer promoting system can be used as a two-turn spring that uses a space between the inner and outer tubes as two spiral flow paths, or a one-turn spring that uses a space between the inner and outer tubes as one spiral flow path. .

Thereby, the flow path length of the flow path between the inner and outer tubes is increased and the flow rate and turbulent flow of the fluid flowing in the flow path are increased. As a result, the fluid flowing in the inner tube is promoted to conduct heat to the fluid flowing between the inner and outer tubes, and the performance per unit length can be improved.

[Previous Technical Literature] [Patent Document]

[Patent Document 1] JP-A-2001-201275 (refer to paragraph number 0032, and Figs. 7 and 8)

However, the above-described double-tube type heat exchanger is configured such that one inner tube is inserted into the inner side of one outer tube. Therefore, it is difficult to make the first flow path formed by the inner side of the outer tube and the outer side of the inner tube and the second flow path formed by the inner side of the inner tube an optimum cross-sectional area ratio of the flow path, and an easy manufacturing method is used. The heat exchange area between the first flow path and the second flow path is increased. As a result, it is difficult to increase the heat exchange rate by the double-casing type heat exchanger (heat transfer tube for heat exchanger) of the prior art, and it is difficult to make the heat exchanger compact because the length of the tube becomes long.

The present invention has been developed in view of the above circumstances, and an object of the invention is to provide a heat transfer tube for a heat exchanger which has a high heat exchange rate and which can be easily manufactured and which can be manufactured finely, and a heat exchanger using the heat transfer tube.

Next, means for solving the above problems will be described with reference to the drawings corresponding to the embodiments.

The heat transfer tube 11 for a heat exchanger according to claim 1 of the present invention is characterized by comprising: an outer tube 13; A plurality of inner tubes 15 are inserted into the outer tube 13 and are disposed such that the distance between the axes of the two is substantially equal in a cross section orthogonal to the axis; the first coil 17 is at least partially fixed to the outer tube The inner peripheral surface 21 is inserted into the plurality of inner tubes 15 on the inner side; at least a part of the second coil 19 is fixed to the inner inner peripheral surface 23 of each inner tube; and the flow path sectional area S1 of the first flow path 25 is externally The inner side of the tube 13 and the outer side of the inner tube 15 are formed; and the flow path cross-sectional area S2 of the second flow path 27 is formed by summing the flow path cross-sectional areas of the respective inner tubes 15, and the flow path cross-sectional area The ratio of S1 is in the range of S1:S2=1:2~2:1.

In the heat transfer tube 11 for a heat exchanger, the outer tube 13 has a first coil 17 partially fixed to the inner peripheral surface 21 of the outer tube, and each of the inner tubes 15 has a second coil 19 partially fixed to the inner peripheral surface 23 of the inner tube. . The first coil 17 and the second coil 19 are functions for achieving disturbance of the fluid and for promoting heat transfer.

A plurality of inner tubes 15 are inserted into the inner side of the first coil 17. Therefore, it is easier to adjust the heat exchange area of the fluid flowing in the first flow path 25 and the flow path sectional area of the second flow path 27 as compared with the case where the inner tube 15 is one. Obtained using an easy manufacturing method.

More specifically, the adjustment can be performed by changing the number of the inner tubes 15 and the diameter of the inner tube 15.

The first flow path formed by the inner side of the outer tube 13 and the outer side of the inner tube 15 The flow path sectional area S1 of 25 and the flow path sectional area S2 of the second flow path 27 of the inner tube 15 are configured to be 1:2 to 2:1. As a result, the cross-sectional area of the flow path of the first flow path 25 is insufficient because S1/S2 is formed at 1/2 or less. In addition, it does not occur because the cross-sectional area of the flow path of the second flow path 27 is insufficient because S1/S2 is formed at 2/1 or more. As described above, by making the inner tube 15 a plurality of roots, it is easy to adjust the flow path sectional area ratio of the first flow path 25 and the second flow path 27, and it is possible to easily approximate the flow path sectional area ratio. Good ratio.

The heat transfer tube 11 for a heat exchanger according to claim 2 is the heat transfer tube 11 for a heat exchanger according to claim 1, wherein the inner tube is located at any position of the first flow path 25 15 plugged in with core material.

In the heat transfer tube 11 for a heat exchanger, by providing the core material in the first flow path 25, the fluid flowing in the first flow path 25 is easily dispersed. In other words, the movement of the fluid on the inner side in the radial direction of the cross-sectional area of the flow path of the first flow path 25 and the outer side in the radial direction is promoted, and the temperature gradient is easily obtained. This result will increase the heat exchange rate. In addition, since the fluid flowing through the first flow path 25 in the portion where the core material is disposed can be eliminated, the flow path cross-sectional area of the first flow path 25 can be reduced and adjusted.

The heat transfer tube 11 for a heat exchanger according to claim 3 is the heat transfer tube 11 for a heat exchanger according to claim 2, wherein the core material is a solid rod 29.

In the heat transfer tube 11 for a heat exchanger, the fluid flowing through the first flow path 25 can be effectively removed by the volume of the solid rod 29.

The heat transfer tube 11 for a heat exchanger according to claim 4 is the heat transfer tube 11 for a heat exchanger according to claim 2, wherein the core material is a coil member.

In the heat transfer tube 11 for a heat exchanger, the flow of the fluid flowing in the vicinity of the coil member of the first flow path 25 can be disturbed or stirred. By the agitation described above, the movement of the fluid flowing in the radial direction inside and the radial direction of the cross-sectional area of the flow path of the first flow path 25 is more effectively promoted, and the temperature gradient is easily obtained. This result will increase the heat exchange rate.

The heat transfer tube for a heat exchanger according to claim 2, wherein the core material is formed into a spiral strip-shaped plate member 47.

In the heat transfer tube 45 for a heat exchanger, the flow of the fluid flowing through the first flow path 25 can be disturbed by stirring the strip-shaped member 47 in a spiral shape or stirred. By the agitation described above, the movement of the fluid flowing in the radial direction inside and the radial direction of the cross-sectional area of the flow path of the first flow path 25 is more effectively promoted, and the temperature gradient is easily obtained. This result will increase the heat exchange rate.

The heat exchanger tube for a heat exchanger according to any one of claims 1 to 2, 3, 4, and 5, wherein the heat transfer tube for a heat exchanger according to any one of claims 1, 2, 3, 4, and 5 includes a bent portion.

In the heat transfer tube 11 for a heat exchanger, the shape of the tube can be configured to have a curved portion that can bend a middle portion or the like at an arbitrary angle, and a curved portion is formed at a position of the curved portion. In the meantime, since the outer tube and the inner tube have the first coil and the second coil, they are not crushed. Further, by forming the shape including the curved portion, the flow path inlet and outlet at both ends can be formed in an arbitrary direction, and the length of the heat transfer tube can be formed while the overall size can be precisely formed.

The heat transfer tube 11 for a heat exchanger according to any one of claims 1 to 2, 3, 4, and 5, wherein the heat transfer tube 11 for heat exchanger according to any one of claims 1 to 2, wherein: In the upper case, the pair of first bending portions 31 and the second bending portions 33 that are bent in the opposite directions at the same radius and the same bending angle.

In the heat transfer tube 11 for a heat exchanger, the shape of the tube is formed into an S-shape which is curved in the opposite direction by the same radius and the same bending angle, so that the length variation of the bent portion of each tube can be canceled. Thereby, all the lengths of the all-straight state before bending can be unified, and the end portions of the respective tubes can be unified on the same surface after being bent into an S-shape.

The heat exchanger according to claim 8 is the heat exchanger for heat exchanger according to any one of claims 1 to 7.

In this heat exchanger, since a plurality of inner tubes are inserted inside one of the outer tubes, and the heat transfer tubes for heat exchangers having the structure in which the coils are arranged in the respective flow paths are formed, heat can be increased. Exchange rate heat exchangers, and thereby delicately constitute a heat exchanger.

The heat transfer tube for a heat exchanger according to claim 1 of the present invention is configured by a plurality of inner tubes and is formed in each flow path. The coil is disposed so that it has a high heat exchange rate and is easy to manufacture and can be delicately constructed.

According to the heat transfer tube for a heat exchanger according to the second aspect of the invention, the heat transfer rate of the fluid flowing through the first flow path can be improved, and the first flow path and the second flow path can be easily adjusted. Flow path sectional area ratio.

According to the heat transfer tube for a heat exchanger according to the third aspect of the invention, the core material of the solid rod disposed in the first flow path can effectively reduce the cross-sectional area of the flow path of the first flow path. Reduction, that is, reduction and adjustment.

According to the heat transfer tube for a heat exchanger according to the fourth aspect of the invention, the coil member disposed in the first flow path can reduce the cross-sectional area of the flow path of the first flow path while facing the first flow path. The flowing fluid is agitated to increase the heat exchange rate.

According to the heat transfer tube for a heat exchanger according to the fifth aspect of the invention, the spiral strip-shaped member disposed in the first flow path can reduce the cross-sectional area of the flow path of the first flow path while stirring The fluid flowing in the first flow path increases the heat exchange rate.

The heat transfer tube for a heat exchanger according to the invention of claim 6 can be configured as a heat transfer tube and can be made compact by providing a curved portion.

According to the heat transfer tube for a heat exchanger according to claim 7, the curved portion is formed in an S-shape in the opposite direction at the same radius and the same bending angle, so that the heat transfer tube can be formed inside and outside. The end portions of the respective tubes are formed on the same surface, and the curved structure that can be made finer is easily manufactured.

The heat exchanger according to claim 8 of the present invention is configured such that a plurality of inner tubes are inserted into the inner side of one outer tube, and the heat exchanger is configured to be a structure in which coils are arranged in the respective flow paths. The heat pipe is composed of, so that a heat exchanger that increases the heat exchange rate can be obtained. Further, by this, the length of the heat transfer tube can be made short, and since the heat transfer tube can be bent, the heat exchanger can be configured in a compact manner.

11‧‧‧ Heat transfer tubes for heat exchangers

13‧‧‧External management

15‧‧‧Inside

17‧‧‧1st coil

19‧‧‧2nd coil

21‧‧‧The inner circumference of the outer tube

23‧‧‧ inner tube inner circumference

25‧‧‧1st flow path

27‧‧‧2nd flow path

29‧‧‧ core material (solid rod)

31‧‧‧1st bend

33‧‧‧2nd bend

47‧‧‧ core material (with plate-like members)

S1, S2‧‧‧ flow path sectional area

Fig. 1 is a side elevational view showing a part of a heat transfer tube for a heat exchanger according to an embodiment of the present invention.

Fig. 2 is a cross-sectional view showing a heat transfer tube for a heat exchanger shown in Fig. 1 in a direction orthogonal to an axis.

Fig. 3 is a plan view showing a heat transfer tube for a heat exchanger formed in an S shape.

Fig. 4 is a view showing the arrow A-A of Fig. 3;

Fig. 5 is a cross-sectional view taken along line B-B of Fig. 3.

Fig. 6 is a cross-sectional view taken along line C-C of Fig. 3.

Fig. 7 is a cross-sectional view showing a heat transfer tube for a heat exchanger disclosed in a modification of the core material.

Fig. 8 is a cross-sectional view showing a heat transfer tube for a heat exchanger shown in Fig. 7 in a direction orthogonal to an axis.

Fig. 9 is a cross-sectional view showing a heat transfer tube for a heat exchanger disclosed in a modification of the core material.

Fig. 10 is a cross-sectional view showing a heat transfer tube for a heat exchanger shown in Fig. 9 in a direction orthogonal to an axis.

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

1 is a side view showing a part of a heat transfer tube for a heat exchanger according to an embodiment of the present invention, and FIG. 2 is a cross-sectional view of the heat transfer tube for heat exchanger shown in FIG. The cross-sectional view of the direction, the third drawing is a plan view of the heat transfer tube for the heat exchanger formed in an S shape, the fourth drawing is a view shown by the arrow AA of the third drawing, and the fifth drawing is the BB line of the third drawing. The cross-sectional view shown in Fig. 6 is a cross-sectional view taken along line CC of Fig. 3.

The structure of the heat transfer tube 11 for a heat exchanger disclosed in the present embodiment includes an outer tube 13, an inner tube 15, a first coil 17, a second coil 19, a flow path sectional area S1, and a flow path sectional area S2.

The outer tube 13 is formed in a circular shape in a cross-sectional shape orthogonal to the axis. The material of the outer tube 13 and the inner tube 15 can be, for example, copper or stainless steel. In addition to this, other metals or alloys may be used as long as they have the same degree of thermal conductivity and can ensure heat-resistant temperature, corrosion resistance, and strength. Further, the outer tube 13 and the inner tube 15 may be any of a seamless tube or an electric seam tube having no joint portion.

The inner tube 15 is composed of a plurality of roots, which are four in the present embodiment, and are inserted in the outer tube 13 in such a manner that the axes are parallel to each other in the same direction, so that the distance between the axes of the mutual is positive with the axis. The intersecting sections are arranged to be substantially equal. That is, the four inner tubes 15 are arranged such that the distance from the axis of the outer tube 13 to the respective axes is formed to be substantially equal. Further, in order to perform heat exchange uniformly, the four inner tubes 15 are arranged in a line connecting the respective axes, and the cross-sectional angle of view is formed into a regular polygonal shape, for example, a square is preferable. Further, the four inner tubes 15 are such that the outer peripheral surfaces of the tubes are separated from each other. Thereby, the fluid can be uniformly flowed inside the outer tube 13. Further, the above-mentioned "distance between the axes of the mutual lines is substantially equal" means that the distance between the longest axes is within a range of 100 to 120% of the distance between the shortest axes.

Further, the number of the inner tubes 15 is not limited to four, and may be two, three, or five or more.

At least a part of the first coil 17 is fixed to the outer peripheral surface 21 of the outer tube. A plurality of inner tubes 15 are inserted into the inner side of the first coil 17. Further, the four inner tubes 15 may be disposed in contact with the first coil 17.

At least a part of the second coil 19 is fixed to the inner circumferential surface 23 of each inner tube. In the present embodiment, each of the second coils 19 is formed in the same shape.

The first coil 17 and the second coil 19 are composed of a metal wire having good electrical conductivity as described above, and are wound into a spiral shape to form a coil spring shape. The first coil 17 and the second coil 19 are fixed to the outer tube inner circumferential surface 21 and the inner tube inner circumferential surface 23 by brazing, for example.

Here, the first flow path 25 is formed by the inner side of the outer tube 13 and the outer side of the inner tube 15 as the flow path sectional area S1. In addition, the second flow path 27 constituted by the cross-sectional area of the flow path of each of the inner tubes 15 is used as the flow path sectional area S2. In the heat transfer tube 11 for a heat exchanger, the ratio of the flow path sectional area S1 to the flow path sectional area S2 is set in the range of S1:S2=1:2 to 2:1. Further, the ratio of the flow path sectional area S1 to the flow path sectional area S2 is preferably S1: S2 = 5: 9 to 9: 5, more preferably S1: S2 = 4: 5 to 5: 4.

At any position of the first flow path 25, a core material is inserted along the inner tube 15. By providing the core material, the fluid flowing in the first flow path 25 can be dispersed. Further, the core material can be used as means for adjusting the ratio of the flow path sectional area S1 to the flow path sectional area S2. A solid rod 29 may also be disposed coaxially at the center of the outer tube 13. In this case, in order to allow the fluid flowing in the first flow path 25 to uniformly flow in the outer tube 13, the solid rod 29 and the outer peripheral surface of the inner tube 15 are preferably separated.

In addition, the core material is not limited to the solid rod 29, and may be a coil member or a strip-shaped member 47, as long as it is an effect of obtaining the dispersion fluid and an effect of adjusting the cross-sectional area ratio of the flow path. Further, the position of the core material may be such that the effect of dispersing the fluid and the effect of adjusting the cross-sectional area ratio of the flow path may be shifted from the axis of the outer tube 13. Further, as long as the above effects can be obtained, the core material may be disposed in a substantially triangular portion by the two inner tubes 15 adjacent to the outer tube 13, or may be formed by the inner tubes 15 and the outer tubes 13 respectively. In total, four of the four substantially triangular portions may be arranged one by one.

More specifically, the outer tube 13 has an outer diameter of 10 mm, an inner diameter of 8.4 mm, and a thickness of 0.8 mm, and the inner tube 15 has an outer diameter of 3 mm, an inner diameter of 2.5 mm, and a thickness of 0.25 mm. The first coil 17 has a wire diameter of 0.3 mm, an inner diameter of 7.5 mm, and an outer diameter of 8.1 mm, and the second coil 19 has a wire diameter of 0.3 mm, an inner diameter of 1.7 mm, and an outer diameter of 2.3 mm. Further, when the core material has a diameter of 1 mm, for example, the flow path sectional area S1 is 15.1 mm ² and the flow path sectional area S2 is 9.08 mm ² by the above numerical value. In this case, the flow path sectional area ratio of the flow path sectional area S1 and the flow path sectional area S2 is formed as S1:S2=1:1.66.

The heat transfer tube 11 for a heat exchanger is a pair of first curved portions 31 which are bent in opposite directions by the same radius and the same bending angle R, for example, 180°, as shown in Fig. 3, and on the same plane. The second curved portion 32 can be formed in an S shape.

In this case, both ends of the outer tube 13 are connected to one end of the T-joint 35. The respective T-joints 35 are connected to the sleeve 37 at the end opposite to the outer tube 13. The sleeve 37 is for closing the first flow path 25 that is open toward the inner side of the T-joint 35, and the inner tube 15 is led to the outside. The respective inner tubes 15 which are led to the outside are sealed by water and inserted into the other sleeves 39. The second flow path 27 of each of the inner tubes 15 is open inside the sleeve 39. Further, the remaining connection portion of the first flow path 25 which is the open T-shaped joint 35 is connected to the connection pipe 41. The first flow path 25 is connected to the connection pipe 41 via a T-joint 35.

Fig. 7 is a cross-sectional view showing a heat transfer tube 43 for a heat exchanger disclosed in a modification of the core material, and Fig. 8 is a heat exchange shown in Fig. 7. FIG. 9 is a cross-sectional view of a heat transfer tube 45 for a heat exchanger disclosed in a modification of the core material, and FIG. 10 is a view showing a heat transfer tube 45 according to a modification of the core material. FIG. A cross-sectional view of the heat transfer tube 45 for heat exchanger in a direction orthogonal to the axis.

Further, the heat transfer tube 11 for a heat exchanger may be a core material as shown in Figs. 7 and 8 . Further, when the core material is a coil member, the number of windings, the wire diameter, and the like may be changed depending on the cross-sectional area ratio of the flow path. Further, as shown in FIG. 9 and FIG. 10, the shape of the core material may be configured not to be the solid rod 29 but to be a strip-shaped member 47 formed in a spiral shape. Further, the second coil 19 into which the respective inner tubes 15 are inserted may have a different shape, number of windings, and wire diameter depending on the inner tube 15 to be inserted.

Next, the action of the heat transfer tube 11 for a heat exchanger having the above configuration will be described.

In the heat transfer tube 11 for a heat exchanger, the outer tube 13 has a first coil 17 partially fixed to the inner peripheral surface 21 of the outer tube, and each of the inner tubes 15 has a second coil 19 partially fixed to the inner peripheral surface 23 of the inner tube. The first coil 17 and the second coil 19 are functions for disturbing the fluid flowing in the respective tubes and for promoting heat transfer.

A plurality of inner tubes 15 are inserted into the inner side of the first coil 17. Therefore, it is easier to adjust the area of the heat exchanger that flows the fluid in the first flow path 25 and adjust the cross-sectional area of the flow path of the second flow path 27, compared to the case where the inner tube 15 is one. It can be obtained by an easy manufacturing method.

More specifically, the adjustment can be performed by changing the number of the inner tubes 15, the diameter of the inner tube 15, and the thickness of the inner tube 15.

The flow path sectional area S1 of the first flow path 25 formed by the inner side of the outer tube 13 and the outer side of the inner tube 15 and the flow path sectional area S2 of the second flow path 27 of the inner tube 15 are configured as follows: 2~2:1. As a result, the cross-sectional area of the flow path of the first flow path 25 is insufficient because S1/S2 is formed at 1/2 or less. In addition, it does not occur because the cross-sectional area of the flow path of the second flow path 27 is insufficient because S1/S2 is formed at 2/1 or more. As described above, by making the inner tube 15 a plurality of roots, it is easy to adjust the cross-sectional area ratio of the flow path of the first flow path 25 and the second flow path 27, and it is possible to easily bring the flow path sectional area ratio closer. The preferred ratio.

Further, in the heat transfer tube 11 for a heat exchanger, by providing the solid rod 29 or the strip-shaped member 17 as a core material in the first flow path 25, the fluid flowing through the first flow path 25 is facilitated. dispersion. In other words, the movement of the fluid on the inner side in the radial direction of the cross-sectional area of the flow path of the first flow path 25 and the outer side in the radial direction is promoted, and the temperature gradient is easily obtained. This result will increase the heat exchange rate. In addition, since the fluid flowing through the first flow path 25 in the portion where the core material is disposed can be eliminated, the flow path cross-sectional area of the first flow path 25 can be reduced and adjusted. Thereby, the thermal conductivity which is transmitted to the fluid flowing through the first flow path 25 can be increased, and the flow path sectional area ratio of the first flow path 25 and the second flow path 27 can be easily adjusted.

Further, with the solid rod 29 as a core material, the fluid flowing through the first flow path 25 can be excluded by the volume of the solid rod 29. As a result, the cross-sectional area of the flow path of the first flow path 25 can be effectively reduced, and Line cuts and adjustments. Further, by increasing or decreasing the volume of the solid rod 29, the thickness of the inner tube 15 can be increased or decreased and the flow path sectional area ratio can be adjusted.

Further, when the coil member or the strip-shaped member 47 is used as the core material, the fluid flowing in the vicinity of the coil member or the strip-shaped member 47 of the first flow path 25 can be disturbed or stirred. By the agitation described above, the movement of the fluid flowing in the radial direction inside and the radial direction of the cross-sectional area of the flow path of the first flow path 25 is more effectively promoted, and the temperature gradient is easily obtained. This result will increase the heat exchange rate. Thereby, the flow path cross-sectional area of the first flow path 25 can be reduced, and the fluid flowing through the first flow path 25 can be stirred to increase the heat exchange rate.

Further, in the heat transfer tube 11 for a heat exchanger, the shape of the tube is formed into an S-shape which is curved in the opposite direction at the same radius and the same bending angle, whereby the length of the bent portion of each tube can be changed. offset. In other words, the lengths of the tubes in the all-straight state before the bending of the S-shape can be made identical, and the ends of the tubes can be unified on the same surface after being bent into an S-shape. As a result, the end portions of the respective tubes are formed on the same surface, and it is possible to easily manufacture a bendable structure that can be made fine.

The following structure is used as a heat exchanger (not shown), and is configured by a plurality of heat transfer tubes 11 and 43 and 45 for heat exchangers of the above-described embodiments, and arranged in parallel to be arranged close to each other to form the same The flat shape, or a plurality of bundles, is formed into a bundle and then combined into a unit of the heat transfer tube column.

a structure in which the arrays are arranged in parallel to each other in the same plane shape Among them, it is possible to laminate the layers into a plurality of layers to constitute a heat exchanger. The unit of the plurality of heat transfer tube rows that are stacked in a layer is connected to each of the first flow paths of the heat transfer tubes for the heat exchangers, for example, and is connected to the second flow paths, respectively. Connected to the primary inlet pipe header, the primary outlet header, the secondary inlet header, and the secondary outlet header.

Further, although the drawings are omitted, the respective pipe joints of the primary heat medium supply pipe, the secondary heat medium supply pipe, the primary heat medium circulation pipe, and the secondary heat medium circulation pipe from the heat exchange device side are connected so that the flow is once made. The primary heat medium after the inlet header box flows into the inner tube 15, for example. The primary heat medium flowing into the inner tube 15 is discharged to the outside from the primary inlet header after heat exchange with the secondary heat medium. The secondary heat medium flowing into the secondary inlet header box flows into the outer tube 13. The secondary heat medium flowing in the outer tube 13 is discharged to the outside from the secondary outlet header after heat exchange with the primary heat medium.

According to the heat exchanger having the above-described structure, the heat medium flowing in the inner tube 15 is disturbed by the second coil 19 provided inside the inner tube 15, and flows while stirring, which is advantageous in comparison with the conventional technique. Heat and heat exchange. In addition, heat exchange is performed with the heat medium of other systems flowing in the gap between the outer tube 13 and the inner tube 15. Further, the heat exchanger is configured such that a plurality of heat transfer tubes 11 composed of the outer tube 13 and the inner tube 15 are parallel to each other, and are arranged in close proximity on the same plane to form one unit, thereby enabling By constituting a plurality of layers, it is possible to reduce the ground contact area while expanding the heat transfer area.

Therefore, due to the heat exchange disclosed in accordance with the present embodiment Since the heat transfer tube 11 can be easily manufactured and the heat exchange rate can be increased, the tube length can be made short, and the tube length can be made short depending on the heat exchanger using the heat transfer tube for the heat exchanger. Delicate.

11‧‧‧ Heat transfer tubes for heat exchangers

13‧‧‧External management

15‧‧‧Inside

17‧‧‧1st coil

19‧‧‧2nd coil

21‧‧‧The inner circumference of the outer tube

23‧‧‧ inner tube inner circumference

25‧‧‧1st flow path

27‧‧‧2nd flow path

29‧‧‧ core material (solid rod)

S1, S2‧‧‧ flow path sectional area

Claims (8)

A heat transfer tube for a heat exchanger, comprising: an outer tube; a plurality of inner tubes inserted into the outer tube and arranged to have a distance between each other on a cross section orthogonal to the axis The first coil is fixed to at least a part of the inner circumferential surface of the outer tube and inserted into the inner plurality of inner tubes on the inner side; at least a part of the second coil is fixed to the inner circumferential surface of each inner tube; the first flow path The flow path sectional area S1 is constituted by the inner side of the outer tube and the outer side of the inner tube, and the flow path sectional area S2 of the second flow path, which is formed by summing the flow path sectional areas of the respective inner tubes, and The ratio of the flow path sectional area S1 is in the range of S1:S2=1:2 to 2:1. The heat transfer tube for a heat exchanger according to claim 1, wherein a core material is inserted along the inner tube at an arbitrary position of the first flow path. The heat transfer tube for a heat exchanger according to claim 2, wherein the core material is a solid rod. The heat transfer tube for a heat exchanger according to claim 2, wherein the core material is a coil member. The heat transfer tube for a heat exchanger according to claim 2, wherein the core material is formed into a spiral strip-shaped plate member. The heat as claimed in any one of claims 1 to 5 A heat transfer tube for an exchanger, comprising: a bent portion. The heat transfer tube for a heat exchanger according to any one of claims 1 to 5, further comprising: a pair of first bends bent in opposite directions at the same radius and the same bending angle on the same plane The second part and the second bending part. A heat exchanger comprising the heat transfer tube for a heat exchanger according to any one of claims 1 to 7.