JP2019066084A - Heat exchanger - Google Patents

Abstract

To provide a heat exchanger that performs heat exchange efficiently and is smaller and cheaper than conventional ones.SOLUTION: A heat exchanger comprises a bottomed cylindrical outer container, a cylindrical partition wall having a diameter smaller than the outer container, and a heat transfer pipe. The partition wall is detachably arranged in the outer container. An upper end of the partition wall is positioned above a water level of fluid in the outer container. In a cylindrical space formed by the outer container and the partition wall, the heat transfer pipe is arranged in a direction intersecting with a direction where fluid flows. Both ends of a heat exchange unit of the heat transfer pipe are respectively arranged at an upper end and lower end of the cylindrical space. At an upper end and lower end of a lateral surface of the outer container, a flow port for fluid is positioned so as to face each other in a horizontal direction.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a heat exchanger, and more particularly to a heat exchanger that can cope with heat exchange treatment with a small flow rate of fluid.

  As a conventional heat exchanger, as shown in FIG. 3, a large number of thin tubes as heat transfer tubes are connected at regular intervals between two tubes, and a sheet is rolled into a cylindrical shape, and the fluid in the water tank It is known to install in.

  In the heat exchanger as described above, a large existing water tank is often used, and there is a drawback that miniaturization is difficult. In addition, the heat exchange efficiency is poor because the heat exchange is performed only by natural convection generated around the heat transfer pipe without the function of concentrating the flow of the fluid around the heat transfer pipe. An object of the present invention is to provide a heat exchanger which can perform heat exchange efficiently and which is smaller and cheaper than conventional products.

  The heat exchanger according to the present invention includes a bottomed cylindrical outer container, a cylindrical partition having a diameter smaller than that of the outer container, and a heat transfer tube, and the partition is removable, and is provided inside the outer container. The upper end of the partition wall is located above the water surface of the fluid in the outer container, and the heat transfer tube is disposed in a direction intersecting the fluid flow direction in the cylindrical space created by the outer container and the partition wall, Both ends of the heat exchange section of the heat transfer tube are respectively disposed at the upper end and the lower end of the cylindrical space, and the upper and lower ends of the side surface of the outer container are provided with fluid flow ports at horizontally opposing positions. .

  In addition to the above-mentioned constitution, as described in claim 2, it is characterized by comprising a cylindrical outer container, a cylindrical partition, and a heat transfer pipe spirally disposed in the cylindrical space.

According to the present invention, since the fluid flows in from the upper end or the lower end of the outer container and flows out from the lower end or the upper end, the flow of the fluid in the cylindrical space is promoted without stagnation, so the heat exchange efficiency in the heat transfer tube Improve. Furthermore, by matching the flow direction of the fluid with the direction of the natural convection of the fluid in the cylindrical space, the flow of the fluid is also promoted by the natural convection, and the heat exchange efficiency can be further improved.
In addition, by setting the flow direction of the heat medium in the heat exchange portion of the heat transfer tube in the opposite direction to the flow direction of the fluid, countercurrent heat exchange that maximizes the temperature difference between the fluid and the heat medium is achieved. To improve the heat exchange efficiency. And, because the upper end of the partition projects above the fluid water surface, there is no flow path at the upper side for the fluid inside the partition to flow out to the outside of the partition, so the fluid is in the cylindrical space, that is, the heat transfer tube. By preferentially flowing in the vicinity, forced convection due to the inflow pressure of the fluid from the outside of the heat exchanger is concentrated in the vicinity of the heat transfer tube. And since the direction of this forced convection also becomes the same direction as the above-mentioned natural convection, heat exchange is further promoted.
As described above, high efficiency heat exchange is realized by aligning the flow direction of the fluid and the direction of forced convection with the direction of natural convection of the fluid, and by making the flow of the heat medium countercurrent to the fluid, and A smaller heat exchanger can be provided.

  Further, according to the second aspect of the present invention, by making the shape of the outer container cylindrical, the shape of the heat transfer tube disposed inside can be made just a coil shape without corners, and as a result, the heat transfer tube Since local bending processing is not required, it can be easily manufactured.

(A) (b) It is a longitudinal cross-sectional view which shows the main internal structures of the heat exchanger of this invention, and the structure of heat exchange. It is a schematic diagram which shows the other form of a heat exchanger tube. It is a schematic diagram which shows the main internal structures of the conventional water tank type heat exchanger.

  Hereinafter, embodiments of the present invention will be described based on the drawings.

  The heat exchanger of the present invention is constituted of a heat transfer pipe 2 and a cylindrical partition 5 in this order from the outside inside the cylindrical outer container 1. By forming these members from resin, a heat exchanger excellent in chemical resistance and corrosion resistance can be manufactured, and application of groundwater, industrial wastewater, hot spring water, etc. as the fluid 8 is also possible.

  By using a resin tank, it is possible to manufacture a heat exchanger which is inexpensive and easy to install. The outer container 1 has a cylindrical shape with a bottom, and is installed with the opening facing upward. By making the shape into a cylindrical shape, the arrangement shape of the heat transfer tube 2 disposed inside can be made into a simple coil shape without corners, and as a result, the local bending processing of the heat transfer tube 2 becomes unnecessary, so it is easy Can be produced. The outer container 1 is provided with one flow port 7a of the fluid 8 at the lower end of the side surface and the other flow port 7b of the fluid 8 at the upper end of the side surface. Further, a grid plate 9 made of resin for supporting the heat transfer pipe 2 and the partition 5 is horizontally disposed at a lower position of the outer container 1 at a position above the one flow passage 7 a of the fluid 8. The fluid 88 can pass through the grid plate 9.

  The heat transfer tube 2 circulates a heat medium (not shown), and by forming it with a resin tube, processing is easy and it can be manufactured at low cost. The heat transfer tubes 2 are placed on the grid plate 9. The upper end 4 a and the lower end 4 b of the heat exchange portion 4 of the heat transfer tube 2 are disposed at the upper end and the lower end of the outer vessel 1 respectively, and the heat exchange portion 4 of the heat transfer tube 2 is a cylinder formed between the outer vessel 1 and the partition 5 It is helically disposed in the space 6 in the direction intersecting the flow direction of the fluid 8. A plurality of resin-made plate-like spacers 10 are attached to the heat transfer tube 2 in order to maintain a space between the heat transfer tube 2 and the partition wall 5. The spacer 10 is long in the vertical direction, has a plurality of holes in the longitudinal direction, and the spiral heat transfer tube 2 is inserted through the holes. As a result, the entire periphery of the surface of the heat transfer tube 2 contacts the fluid 8 without the heat transfer tube 2 coming into close contact with the partition wall 5, and the heat exchange efficiency is improved. When the heat medium is cooled by heat exchange, the heat medium flows in from the upper end 4a of the heat exchange unit 4 of the heat transfer tube 2, passes through the spiral inner circumference and reaches the lower end 4b, and is then discharged from the heat exchanger . On the other hand, in the case of heating the heat medium by heat exchange, it flows from the lower end 4b of the heat exchange part 4 of the heat transfer tube 2, passes through the spiral inner circumference and reaches the upper end 4a, and is then discharged from the heat exchanger.

  The cylindrical partition wall 5 is made of a plate material made of resin, and is disposed with the cylinder axial direction up and down. The upper end of the partition 5 is disposed above the water surface S of the fluid 8. With regard to the method of installing the partition walls 5, when the resin plate is inserted into the inner space of the spiral heat transfer tube 2 in a state of being rolled into a cylindrical shape having a smaller diameter than at the completion of arrangement, and placed on the grid plate 9, Since the cylindrical space 6 can be formed with the minimum thickness, it can flow through the cylindrical space 6 because it can be formed to have the minimum thickness by remaining in contact with the spacer 10 attached to the heat transfer tube 2 by the biasing force that tries to spread outward. The required flow rate of fluid 8 can be minimized. In addition, since the partition wall 5 is lightweight, it can be easily removed even when the heat transfer tube 2 needs to be cleaned, and the maintenance performance is excellent.

  The mechanism of heat exchange when the heat medium is cooled by the fluid 8 is shown in FIG. The heat medium heated by an external device or the like (not shown) flows in from one heat medium flow port 3a of the heat transfer tube 2 and passes sequentially through the spiral heat transfer tube 2 and descends sequentially. Heat exchange with the fluid 8 that has flowed into the cylindrical space 6 from one of the flow openings 7a of the fluid 8, is cooled, passes through the lower end 4b of the heat exchange unit 4, and then the heat exchanger from the other heat medium flow opening 3b Leak out. On the other hand, the fluid 8 heated by heat exchange flows upward in the cylindrical space 6 by natural convection in addition to the inflow pressure when flowing from the outside of the heat exchanger, and the fluid 8 at the upper end of the outer container 1 It is discharged from the other distribution port 7b of That is, the flow direction of the heat medium (from top to bottom) is opposite flow heat exchange opposite to the flow direction of the fluid 8 (from bottom to top), and the temperature difference between the fluid 8 and the heat medium is maximized. It can be used to improve the heat exchange efficiency.

  Further, since the upper end of the partition wall 5 is positioned above the water surface S of the fluid 8, the fluid 8 which has flowed into the outer container from the one flow opening 7a of the fluid 8 at the lower end of the outer container 1 It flows preferentially in the cylindrical space 6 which has the other communication port 7b of the fluid 8 at the upper part than the non-partition wall 5 inner space. Therefore, the fluid 8 inside the partition 5 hardly flows as compared with the fluid 8 in the cylindrical space 6. As a result, the flow of the fluid 8 is concentrated in the cylindrical space 6, that is, in the vicinity of the spiral heat transfer tube 2. As a result, forced convection due to the inflow pressure when the fluid 8 flows in from the outside of the heat exchanger is concentrated in the vicinity of the heat transfer tube 2, and the direction of this forced convection (from bottom to top) is the natural convection (from bottom to top). Since the directions are the same, the flow of the fluid 8 is promoted and heat exchange with high efficiency can be performed.

  In the case of heating the heat medium, as shown in FIG. 1 (b), the heat medium and the fluid 8 flow in the opposite direction to that during the cooling, and the natural convection and forced convection of the fluid 8 are similarly performed. It realizes heat exchange promotion and countercurrent heat exchange, and performs highly efficient heat exchange.

  The heat exchanger according to the present invention is applicable to a small flow of fluid 8 as long as the flow of the fluid 8 inside the partition 5 is small and the flow rate of the fluid 8 flowing through the cylindrical space 6 can be secured. Moreover, by semi-burying the outer container 1 in the ground, the height of the fluid 8 inlet / outlet on the drainage side can be applied to a self-injection well or the like with a low head. Since the self-injection well is naturally discharged into the spouting water, it is unnecessary to study the water source and the drainage destination, and underground piping is also unnecessary, so installation can be performed easily and inexpensively. Therefore, it is suitable also for the heat pump system etc. of a home-use air conditioner. In the case of using industrial water or hot spring water, if the water source is at a high position, power from the outside is unnecessary as in the case of the self-injection well.

Table 1 shows the measurement results of the heat transfer rate [W / (Km ² )] (exchange heat quantity / (average temperature difference / total area)) in the heat exchanger of the present invention and the conventional water tank type heat exchanger. The volume of the outer vessel 1 of the heat exchanger of the present invention is 10.4% of the volume of the water tank of the conventional water tank type heat exchanger, and the total surface area ratio of the heat exchange tubes is 44%. Each of “1” to “5” in the table indicates a measured value under the following conditions.
<< 1 >> Conventional Water Tank Type Heat Exchanger << 2 >> Heat Exchanger of the Present Invention-Configuration of the Present Embodiment << 3 >> Heat Exchanger of the Present Invention-In the configuration of the present embodiment, the flow direction of the heat medium is reversed In the case of the direction 44 熱 Heat exchanger of the present invention-in the configuration of the present embodiment, when the flow direction of the heat medium and the flow direction of the ground water are reversed 《5 《heat exchanger of the present invention-this In the configuration of the embodiment, when the flow direction of the groundwater is reversed

  The measured values of heat transfer rate are "2"> "3"> "4"> "5"> "1", and the heat exchanger "2" of the present invention is more than three times as large as the conventional water tank type heat exchanger. It can be seen that the heat transfer rate is realized. In addition, in «3» to «5», it is a study result in which the flow direction of the fluid 8 or the heat medium is reverse to that of the present embodiment, and even if the flow direction of the fluid 8 or the heat medium is only one It has been confirmed that the heat exchange performance is lowered if the direction is the reverse of the above.

  The present invention is not limited to the above embodiments. For example, the constituent material of the partition 5 is not limited to a resin plate, and it may be a cylindrical solid or the like as long as it can limit the flow of the fluid 8 inside, and the lower end of the partition 5 is in contact with the bottom surface of the outer container 1 It is also good. Further, the heat transfer tubes 2 may be plural, and the shape may be stepwise arranged as shown in FIG.

1 Outer container
2 Heat transfer tube
3a One heat medium circulation port
3b The other heat medium flow port
4 Heat exchange section of heat transfer line
4a Heat Exchanger Top
4b lower end of heat exchange section
5 bulkheads
6 cylindrical space
7a One fluid port
7b The other fluid port
8 fluid
9 grid board
10 spacer

Claims (2)

  A bottomed cylindrical outer container, a cylindrical partition having a diameter smaller than that of the outer container, and a heat transfer tube are provided. The partition is removable and disposed inside the outer container. The upper end of the partition is: The heat transfer tube is disposed in a direction intersecting with the flow direction of the fluid in the cylindrical space formed above the water surface of the fluid in the outer vessel and generated by the outer vessel and the partition, both ends of the heat exchange portion of the heat transfer tube A heat exchanger characterized in that the heat exchanger is disposed at the upper end and the lower end of the cylindrical space respectively, and has fluid circulation ports at positions opposite to each other in the horizontal direction at the upper end and the lower end of the outer container side surface.   The heat exchanger according to claim 1, further comprising a cylindrical outer container, a cylindrical partition, and a heat transfer pipe spirally disposed in the cylindrical space.

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