JP2018194213A - Heat exchanger - Google Patents

Abstract

To prevent heat conduction between juxtaposed heat exchange pipes.SOLUTION: A heat exchanger 10 comprises: a plurality of heat exchange pipes 12, 14 arranged in parallel; and a spacer 18 arranged between a forward heat exchange pipe 12 and a backward heat exchange pipe 14 out of the heat exchange pipes 12, 14 arranged in parallel, and configured to regulate an interval between the heat exchange pipes 12, 14. The spacer 18 is a cylindrical body having a hollow space 18a closed in a state where gas is encapsulated, and the hollow space 18a is arranged between the heat exchange pipes 12, 14.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a heat exchanger that uses underground heat.

  The deep part of the ground is maintained at a constant temperature throughout the year, with temperatures lower than the outdoor temperature in summer and higher than the outdoor temperature in winter. In order to use the underground heat, underground heat exchangers buried in the underground are known. The underground heat exchanger is connected to a load device such as a heat pump, an air conditioner or a snow melting device, and a heat medium such as water or antifreeze is circulated, and a U-tube type pipe (for example, a patent) Reference 1), a spiral type configured in a spiral shape, and the like have been proposed. The U-tube heat exchanger has a forward heat exchange pipe and a return heat exchange pipe folded back from the lower end of the forward heat exchange pipe so that they are parallel to each other. Sometimes called.

JP 2006-234340 A

  The heat exchanger of Patent Document 1 is formed integrally by connecting the forward heat exchange pipe and the return heat exchange pipe by a guide portion, or connecting the forward heat exchange pipe and the return heat exchange pipe. In other words, the outward heat exchange pipe and the return heat exchange pipe are separated from each other. In the heat exchanger of Patent Document 1, since the joint made of the same resin as the guide part and the heat exchange pipe made of resin or the like has a higher thermal conductivity than the soil, it is returned to the forward heat exchange pipe through the guide part and the joint. The problem of heat exchange with the road heat exchange pipe is pointed out.

  The present invention has been proposed in view of the above-described problems related to the prior art, and is preferably proposed to solve these problems. The heat conduction between the parallel forward heat exchange pipe and the return heat exchange pipe is performed. It aims at providing the heat exchanger which can prevent.

In order to overcome the above-mentioned problems and achieve an intended object, a heat exchanger according to claim 1 of the present application is
A heat exchanger embedded in the ground,
A plurality of heat exchange tubes arranged in parallel;
A spacer that is disposed between the heat exchange pipe for the forward path and the heat exchange pipe for the return path among the plurality of heat exchange pipes arranged in parallel, and that defines a space between the heat exchange pipes; ,
The said spacer is a cylindrical body which has the hollow space closed in the state with which the gas was enclosed, and makes it a summary that the said hollow space is arrange | positioned between the said heat exchange tubes.
According to the first aspect of the present invention, the forward heat exchange pipe and the return heat exchange are performed by the spacer arranged between the forward heat exchange pipe and the return heat exchange pipe arranged in parallel. It can be defined that there is a predetermined distance between the tubes. The spacer disposed between the heat exchange pipe for the outward path and the heat exchange pipe for the return path is a cylindrical body having a hollow space, and the gas sealed in the hollow space is more heated than the soil and the material constituting the spacer. Since the conductivity is low, it is possible to prevent heat from moving between the forward heat exchange pipe and the return heat exchange pipe through the spacer. Thus, the heat exchanger prevents heat conduction between the forward heat exchange pipe and the return heat exchange pipe, so that the heat exchange efficiency can be improved.

The invention according to claim 2 is characterized in that the spacer is disposed at least in an upper part near the ground surface between the forward heat exchange pipe and the return heat exchange pipe arranged in parallel. And
According to the invention which concerns on Claim 2, a spacer is arrange | positioned at least on the upper part of a heat exchanger with a large temperature difference of the heat medium which distribute | circulates the heat exchange pipe | tube for an outward path, and the heat medium which distribute | circulates the heat exchanger pipe for return paths Thus, heat conduction between the forward heat exchange pipe and the return heat exchange pipe can be appropriately prevented.

In the invention which concerns on Claim 3, the said spacer is arrange | positioned so that it may extend along this heat exchange pipe between the said heat exchange pipe for the outward path | routes arrange | positioned so that it may be paralleled, and the said heat exchange pipe for return paths It is a summary.
According to the invention which concerns on Claim 3, it arrange | positions so that a spacer may be extended along a heat exchange pipe, By the high heat insulation which a spacer has, it is the heat exchange pipe for an outward path, and the heat exchange pipe for a return path Heat conduction between them can be appropriately prevented over the extending direction of the heat exchange tube.

The invention according to claim 4 is characterized in that the spacer is formed in a cylindrical shape.
According to the invention which concerns on Claim 4, by arrange | positioning a spacer so that an arc-shaped outer peripheral surface may contact | connect a heat exchange pipe, the contact surface of a heat exchange pipe and a spacer can be reduced, The heat conduction with the spacer can be further prevented.

The gist of the invention according to claim 5 is that the spacer has flexibility capable of being bent in a direction intersecting with the extending direction of the heat exchange tube.
According to the invention which concerns on Claim 5, a spacer can be easily arrange | positioned along a heat exchange pipe | tube with the flexibility of a spacer.

  The heat exchanger according to the present invention can prevent heat conduction between the parallel forward heat exchange pipe and the return heat exchange pipe.

It is explanatory drawing which shows the embedding condition of the heat exchanger which concerns on the suitable Example of this invention. It is a schematic perspective view which shows a part of heat exchanger of an Example. It is sectional drawing which cut | disconnects and shows the heat exchanger of an Example to radial direction. It is explanatory drawing which shows the installation process of the heat exchanger of an Example. It is explanatory drawing which shows the principal part of the heat exchanger of the example of a change. It is sectional drawing which cut | disconnects and shows the heat exchanger of the example of a change to radial direction.

  Next, a preferred embodiment of the heat exchanger according to the present invention will be described below with reference to the accompanying drawings.

  As shown in FIG. 1, the heat exchanger 10 according to the embodiment is a vertical buried type in which a plurality of (two in the embodiment) heat exchange tubes 12 and 14 are buried vertically so as to be parallel to each other. . The heat exchanger 10 is disposed so as to be parallel to the forward heat exchange pipe 12 (hereinafter simply referred to as the forward pipe) 12 embedded in the soil so as to extend linearly in the vertical direction, And a return heat exchanger pipe (hereinafter simply referred to as a return pipe) 14 embedded in the soil so as to extend in the vertical direction. Further, the heat exchanger 10 includes a connecting portion 16 that connects the lower end of the forward path pipe 12 and the lower end of the return path pipe 14. In the heat exchanger 10, the upper end (upstream) of the forward path pipe 12 and the upper end (downstream) of the return path pipe 14 are connected to a load device (not shown) such as a heat pump, a cooling / heating device, or a snow melting device. In the heat exchanger 10, a heat medium such as water or antifreeze liquid flows from the load device to the forward pipe 12, and flows from the lower end of the forward pipe 12 to the lower end of the return pipe 14 via the connecting portion 16. To the load device. And the heat exchanger 10 is comprised so that the heat medium which distribute | circulates between load devices may extract heat from underground in the winter when temperature is low, for example, or radiates heat into the ground in summer when temperature is high.

  The heat exchange pipes 12 and 14 are formed of pipe materials through which a heat medium can flow and heat exchange between the heat medium flowing through the inside and the outside soil, such as polyethylene pipes, cross-linked polyethylene pipes, polybutenes. A flexible tube material such as a tube or a composite tube of resin and metal can be used. Among these, a polyethylene pipe is preferably used from the viewpoints of flexibility, corrosion resistance, strength, heat-fusibility, underground heat temperature range, economy, and the like. As shown in FIGS. 2 and 3, the heat exchange pipes 12 and 14 have a flat cross-sectional shape cut in the radial direction perpendicular to the length direction (vertical direction at the time of embedding). It is a substantially “oval” cross-sectional shape composed of a long side extending and a short side extending in an arc shape. The heat exchanger 10 is arranged so that the forward path pipe 12 and the return path pipe 14 are in parallel with the long sides facing each other. The heat exchanger 10 is a flow required for the flow of the heat medium to the minimum of the virtual circle (the dashed line in FIG. 3) centering on the vertical axis passing through the center of the forward pipe 12 and the return pipe 14. It is set so that both the outgoing path pipe 12 and the return path pipe 14 having a cross section can be accommodated. At the same time, the heat exchanger 10 is set so that the distance between the forward pipe 12 and the return pipe 14 is maximized in the virtual circle.

  As shown in FIG. 1 to FIG. 3, the heat exchanger 10 is arranged between the forward pipe 12 and the return pipe 14 among the plurality of heat exchange pipes arranged in parallel, and the forward pipe 12 and a spacer 18 that defines the distance between the return pipe 14 and the return pipe 14. The spacer 18 is a cylindrical body having a hollow space 18 a that is closed in a state where gas is sealed, and is arranged so that the hollow space 18 a is interposed between the forward path pipe 12 and the return path pipe 14. As the spacer 18, a cylindrical pipe material such as a polyethylene pipe, a cross-linked polyethylene pipe, a polybutene pipe, or a resin-metal composite pipe can be used, and among these, a polyethylene pipe is preferably used from the viewpoint of cost reduction. Moreover, the spacer 18 is good to have the flexibility which can be bent in the radial direction which cross | intersects the length direction (extending direction) of the heat exchange pipes 12 and 14. FIG. The spacer 18 of the embodiment is a polyethylene pipe having flexibility, and the opening at both ends is closed with a sealing material such as a cap or a tape to form a hollow space 18a in which the inside of the cylindrical body is closed. As the gas sealed in the spacer 18, air, nitrogen gas, carbon dioxide gas, rare gas, or the like can be used. In particular, air is preferable as the gas from the viewpoints of workability, availability, cost, and the like. In addition, if a gas having a lower thermal conductivity than air (for example, argon gas, krypton gas, xenon gas, etc.) is sealed in the spacer 18, the heat insulation can be further improved.

  As shown in FIGS. 1 and 2, the spacer 18 is disposed between the forward pipe 12 and the return pipe 14 that are arranged in parallel. The spacer 18 of the embodiment is continuously disposed between the forward pipe 12 and the return pipe 14 so as to extend in the vertical direction along the forward pipe 12 and the return pipe 14. In the heat exchanger 10, the length direction of the forward path pipe 12 and the return path pipe 14 is aligned with the length direction of the spacer 18, and the outer circumferential surface of the spacer 18 bent in an arc shape is a straight line of the forward path pipe 12 and the return path pipe 14. Line contact in the longitudinal direction with the typical longitudinal side. The spacer 18 is attached to the forward path pipe 12 and the return path pipe 14 by bonding with a sticking object such as a tape, or a binding tool such as a binding wire or a binding band. In the heat exchanger 10 of the embodiment, the spacer 18, the outward pipe 12, and the return pipe 14 are fixed to each other by a tape, a binding band, or the like (not shown) provided at an appropriate place in the length direction.

  As shown in FIG. 1, the heat exchanger 10 is good to arrange | position the spacer 18 at least in the upper part close | similar to the earth surface between the outward path pipe 12 and the return path pipe 14 arrange | positioned so that it may be parallel. When the heat exchanger 10 according to the embodiment is embedded, a spacer 18 is arranged from the upper part close to the ground surface to the connecting part 16 constituting the lower end of the heat exchanger 10, and the heat exchange tubes 12, 14. The spacing is defined by the spacer 18 over the entire length of the buried portion. In the heat exchanger 10, the spacer 18 may be disposed corresponding to a portion where the temperature difference between the heat medium flowing in the forward pipe 12 and the heat medium flowing in the return pipe 14 is large, and the temperature difference of the heat medium is small. The spacer 18 may be omitted at the lower part near the connecting part 16. It is desirable that the heat exchanger 10 is disposed from the upper part of the embedded portion of the heat exchange pipes 12 and 14 to more than half of the embedded depth of the heat exchange pipes 12 and 14, and from the upper part of the embedded part of the heat exchange pipes 12 and 14. It is more desirable to arrange the heat exchanging pipes 12 and 14 at 2/3 or more of the embedding depth.

  The heat exchanger 10 may be installed as follows, for example. First, the excavation hole 20 is formed in the vertical direction by drilling or the like (FIG. 4A). The heat exchange tubes 12 and 14 are respectively fed out from the two bobbins 22 and 22 around which the long heat exchange tubes 12 and 14 are wound. In addition, the front-end | tip of the heat exchange pipes 12 and 14 is connected by the connection part 16 (FIG. 4 (a)). Similarly, the spacer 18 fed out from the bobbin 24 around which the long spacer 18 whose lower end opening is capped is wound is installed between the heat exchange pipes 12 and 14 arranged in parallel by the connecting portion 16, and the tape The spacer 18 is fixed to the heat exchange tubes 12 and 14 with a binding band or the like. Then, the heat exchange tubes 12, 14 and the spacer 18 are fed out from the bobbins 22, 22, and 24, and the heat exchange tubes 12, 14 and the spacer 18 are inserted into the excavation hole 20 to a predetermined depth (FIG. 4B). At this time, the spacer 18 is fixed to the heat exchange pipes 12 and 14 at an appropriate place with a tape or a binding band, and the end of the spacer 18 is sealed with a cap or tape, thereby sealing the spacer 18 with air as gas. . And after inserting the heat exchange pipe | tubes 12 and 14 to predetermined depth, the heat exchanger 10 is installed in the ground by refilling the excavation hole 20 (FIG.4 (c)).

(Effects of Example)
Next, the operation of the heat exchanger 10 according to the embodiment will be described. The heat exchanger 10 may be defined so that the distance between the forward path pipe 12 and the return path pipe 14 is a predetermined interval by the spacer 18 sandwiched between the forward path pipe 12 and the return path pipe 14 arranged in parallel. it can. The spacer 18 disposed between the outgoing pipe 12 and the return pipe 14 is a cylindrical body having a hollow space 18 a, and the gas sealed in the hollow space 18 a is more heated than the soil and the resin material constituting the spacer 18. Since the conductivity is low, heat can be prevented from moving between the forward path pipe 12 and the return path pipe 14 through the spacer 18. As described above, in the heat exchanger 10, the distance between the forward path pipe 12 and the return path pipe 14 is appropriately secured, and the forward path pipe 12 and the return path pipe 14 are provided by the spacer 18 having a lower thermal conductivity than the soil. Therefore, the efficiency of heat collection and heat dissipation is improved.

  In the heat exchanger 10, the temperature difference between the heat medium that flows through the forward pipe 12 and the heat medium that flows through the return pipe 14 increases toward the top of the heat exchanger 10. Therefore, the heat exchanger 10 can appropriately prevent heat conduction between the forward path pipe 12 and the return path pipe 14 having a large temperature difference if the spacer 18 is disposed at least in the upper part near the ground surface. Further, by arranging the spacer 18 so as to extend along the heat exchange pipes 12, 14, the heat conduction between the forward pipe 12 and the return pipe 14 is caused by the high heat insulation property of the spacer 18. It can prevent appropriately over the extension direction of the exchange pipes 12 and 14. FIG. Here, like the heat exchanger 10 of the embodiment, the spacer 18 is arranged from the upper part to the upper side of the connecting portion 16, so that the spacer extends over the entire length of the embedded forward path pipe 12 and return path pipe 14. Heat conduction can be prevented by 18 and the efficiency of the heat exchanger 10 can be further increased. Further, by continuously arranging the spacer 18 between the forward pipe 12 and the return pipe 14, the forward pipe 12 and the return pipe 14 approach or come into contact with each other due to the pressure of the backfilled soil or the like. Can be prevented. Thus, the efficiency of the heat exchanger 10 can be further enhanced by appropriately securing the distance between the forward path pipe 12 and the return path pipe 14 by the spacer 18.

  The spacer 18 is formed in a cylindrical shape and is disposed so that the arc-shaped outer peripheral surface is in contact with the heat exchange tubes 12 and 14. Therefore, the heat exchanger 10 can reduce the contact surface between the heat exchange tubes 12 and 14 and the spacer 18, and can further prevent heat conduction between the heat exchange tubes 12 and 14 and the spacer 18. Further, in the heat exchanger 10, since the gap formed between the arc-shaped outer peripheral surface of the spacer 18 and the heat exchange pipes 12 and 14 is filled with soil, the heat exchange pipes 12 and 14 and the soil are connected to each other. It is possible to minimize the blocking of the contact area with the spacer 18. Therefore, even if the heat exchanger 10 is arranged so that the spacer 18 is in contact with the heat exchange pipes 12 and 14, heat exchange between the heat exchange pipes 12 and 14 and the soil is not hindered by the spacer 18, and the heat exchange 10 is efficiently performed with the soil. Heat exchange is possible.

  By using the spacer 18 having a flexibility that can be bent in the radial direction, the spacer 18 can be arranged along the heat exchange tubes 12 and 14 by the flexibility of the spacer 18. Easy to do. As described above, the heat exchange tubes 12 and 14 are packed in a state of being wound around the bobbin 22, and some curl remains on the heat exchange tubes 12 and 14 drawn from the bobbin 22. In order to properly arrange the heat exchange tubes 12 and 14, the spacer 18 needs to be bent. Further, like the heat exchange tubes 12 and 14, the spacer 18 can be prepared in a wound packing form, and there is an advantage that handling becomes easy. In addition, you may correct the curl of the heat exchange pipes 12 and 14 using the spacer 18 which is harder to bend than the heat exchange pipes 12 and 14.

(Example of change)
The present invention is not limited to the configuration described above, and can be modified as follows, for example.

(1) In the embodiment, a heat exchanger composed of two heat exchange pipes has been described. However, the heat exchanger is not limited to this, and the heat exchanger has a plurality of pairs of forward heat exchange pipes and return heat exchange pipes. It may be. For example, like the heat exchanger 30 of the modified example shown in FIG. 5 and FIG. 6, there are two sets of a forward path pipe (forward path heat exchange pipe) 12 and a return path pipe (return path heat exchange pipe) 14. The present invention can be applied to anything. The heat exchanger 30 of the modified example includes a first set of the forward path pipe 12 and the return path pipe 14 whose lower ends are connected by the connection section 16, and the forward path 12 and the return path whose lower ends are connected by the connection section 16. A second set of tubes 14 is provided. The heat exchanger 30 is arranged such that the first set of heat exchange tubes 12 and 14 and the second set of heat exchange tubes 12 and 14 are changed in angle by 90 °, and the four heat exchange tubes 12 are arranged. , 14, 12, and 14 are arranged in a circular array at intervals of 90 °. In the heat exchanger 30, the connecting portion 16 of the other set is sandwiched between the outgoing pipe 12 and the returning pipe 14 of one set, and the position of the connecting portion 16 is set vertically between the one set and the other set. They are combined in a shifted state. In the heat exchanger 30 of the modified example, the spacer 18 is disposed so as to be sandwiched between the four heat exchange tubes 12, 14, 12, and 14, and the interval between the opposed heat exchange tubes 12 and 14 is defined. In addition, in the heat exchanger 30 of the modification shown in FIG. 5 and FIG. 6, the same code | symbol as an Example is attached | subjected to the structure similar to an Example, and detailed description is abbreviate | omitted. Also, the heat exchanger 30 of the modified example has the same effects as the above-described embodiment.

(2) In the embodiment, the cross-sectional shape of the heat exchange tube is formed in a flat shape. In addition, there exists an advantage which can minimize the external shape of the whole heat exchanger, ensuring the space | interval of the parallel heat exchange pipe | tube and the distribution area of a heat medium by making a heat exchange pipe flat shape like an Example. .
(3) In the embodiment, the spacer is formed in a cylindrical shape, but the present invention is not limited to this, and may have other shapes such as a rectangular tube shape or a polygonal tube shape.
(4) In the embodiment, one spacer is continuously arranged. However, the present invention is not limited to this, and a plurality of spacers may be arranged in series in the vertical direction. At this time, the spacers arranged in series may be spaced apart or may be arranged so as to contact each other.
(5) The number of spacers disposed between the parallel heat exchange tubes is not limited to one, and two or more spacers may be disposed between the parallel heat exchange tubes. In this case, spacers having the same shape may be used, or spacers having different shapes may be used in combination.
(6) When there are a plurality of sets of the forward path heat exchange pipe and the return path heat exchange pipe, a configuration in which two or more sets of heat exchange pipes are connected by one connecting portion may be employed.
(7) A positional deviation prevention mechanism such as a protrusion or a depression for preventing the positional deviation of the spacer may be provided at one or a plurality of positions of the forward path heat exchange pipe, the return path heat exchange pipe or the spacer.
(8) In the embodiment, the cross-sectional shapes of the outward heat exchange pipe and the return heat exchange pipe are the same flat shape. However, the present invention is not limited to this, and both are different, for example, one is flat and the other is circular. It may be a shape.
(9) The cross-sectional shape of the heat exchange pipe is not particularly limited as long as the heat exchange pipe can be arranged most efficiently in the virtual circle when there are a plurality of sets of the forward path heat exchange pipe and the return path heat exchange pipe. . For example, the cross-sectional shape of the heat exchange tube may be all flat, only one or two may be flat, and the rest may be circular. When two places are flat, the forward heat exchange pipe and the return heat exchange pipe to be paired may be flat, or the two forward heat exchange pipes are flat and two sets of The return path heat exchange tube may be circular.
(10) If the space between the forward heat exchange pipe and the return heat exchange pipe is within the virtual circle described with reference to FIG. By the 1 or several spacer to arrange | position, you may become longer than the diameter or longitudinal side of the heat exchange tube in the cross section cut | disconnected by radial direction.
(11) The spacer and the heat exchange tube may be fixed by a method other than tape or a binding band.

10, 30 heat exchanger, 12 forward pipe (outward heat exchange pipe, heat exchange pipe),
14 Return pipe (return path heat exchange pipe, heat exchange pipe), 18 spacer, 18a hollow space

Claims (5)

A heat exchanger embedded in the ground,
A plurality of heat exchange tubes arranged in parallel;
A spacer that is disposed between the heat exchange pipe for the forward path and the heat exchange pipe for the return path among the plurality of heat exchange pipes arranged in parallel, and that defines a space between the heat exchange pipes; ,
The said spacer is a cylindrical body which has the hollow space closed in the state with which the gas was enclosed, The said hollow space is arrange | positioned between the said heat exchange tubes, The heat exchanger characterized by the above-mentioned.   2. The heat exchanger according to claim 1, wherein the spacer is disposed at least at an upper portion close to a ground surface between the forward heat exchange pipe and the return heat exchange pipe arranged in parallel.   The said spacer is arrange | positioned so that it may extend along this heat exchange pipe between the said heat exchange pipe for an outward path and the heat exchange pipe for a return path which are arrange | positioned in parallel. The described heat exchanger.   The heat exchanger according to any one of claims 1 to 3, wherein the spacer is formed in a cylindrical shape.   The said spacer is a heat exchanger as described in any one of Claims 1-4 which has the flexibility which can be bent in the direction which cross | intersects the extension direction of the said heat exchange pipe | tube.

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