JP6245510B2 - Heat receiving device and solar heat utilization system - Google Patents

Description

  The present invention relates to a heat receiving device and a solar heat utilization system.

  In recent years, research and development of technologies using natural energy have been actively conducted. For example, in the technical field where sunlight is collected and used as energy, sunlight is condensed on the part where the working fluid flows with a curved reflector extending like a bowl, and steam is generated to generate power. (For example, refer to Patent Document 1) and other various systems (for example, refer to Patent Document 2-4) have been devised.

Japanese Patent Laid-Open No. 10-9680 JP 2000-17749 A JP 2012-67948 A JP 2012-63086 A

  A heat receiving device installed in a portion where sunlight is collected cannot receive the heat of sunlight unless the sunlight hits the working fluid path. However, when the path of the working fluid touches the outside air, it contributes to a decrease in the temperature of the working fluid. Therefore, it is conceivable to suppress heat radiation from the path to the outside air by constructing a heat insulating material except for the part where the sunlight hits the path of the working fluid. When the sunlight condensing location is not in the whole route but discretely in the middle of the route, it is presumed that the heat radiation suppressing effect by the construction of the heat insulating material is further enhanced.

  However, since a heat insulating material cannot be applied to a portion that receives sunlight in the route of the heat receiving device, the route must be brought into contact with outside air for the portion.

  Then, this application makes it a subject to provide the heat receiving apparatus and solar heat utilization system which suppress the heat radiation from the part which sunlight strikes among the paths of the working fluid installed in the part where sunlight condenses.

  In order to solve the above-mentioned problem, in the present invention, the first path through which the working fluid circulates is a path of the working fluid contained in the heat insulating material, and the light to be collected from which sunlight is collected in the first path. The second path through which the working fluid that recovers the heat around the light-collected part is provided in the process of passing through the opening for applying sunlight to the part.

  Specifically, the heat receiving device of the present invention includes a first path through which a working fluid flows and the first path, and the light to be collected in which sunlight is collected in the first path. A heat insulating material provided with an opening for applying sunlight to a part, and a path of a working fluid contained in the heat insulating material together with the first path, and the collected material in the process of passing through the opening A second path through which a working fluid that recovers heat around the light section flows.

Since the heat insulating material is provided with an opening for applying sunlight to the light collection portion, the heat collection portion has heat radiation from the opening to the outside. However, the heat receiving device is formed so that the second path passes through the periphery of the first path at the opening. That is, a part of the member forming the second path is exposed in the opening. Therefore, the working fluid that circulates in the second path collects the heat around the light collection part in the process of passing through the opening. For this reason, if it is the said heat receiving apparatus, in order to irradiate sunlight to a to-be-condensed part, the thermal radiation to the exterior from the opening part inevitably formed in a heat insulating material is suppressed as much as possible. Therefore, the said heat receiving apparatus can suppress the heat radiation from the part which sunlight strikes among the paths of the working fluid installed in the part where sunlight condenses.

  Note that the second route may be connected to the first route. If the second path is connected to the first path, the working fluid flowing in the second path is preheated in the process of passing through the opening, and then flows to the first path. The heat recovery efficiency of the entire device is increased.

  The second path may be arranged in parallel with the first path, and may be formed so as to pass behind the first path in the opening. If the second path is formed so as to pass behind the first path, the second path does not interfere with the sunlight before hitting the first path. Therefore, the working fluid flowing through the first path can sufficiently absorb solar heat.

  In addition, the first path and the second path are each formed by dividing the inside of the pipe material into two along the longitudinal direction, and the light collection portion is in the middle of the first path. It may be formed by a semicircular tube plate disposed so as to block the first path before and after the open portion of the partially formed tube material and a thin tube joined to the tube plate. If the heat receiving device is formed in this way, the space in the opening can be made relatively small, and heat radiation from the first path can be suppressed as much as possible.

  Moreover, the said to-be-condensed part may be formed in multiple places in the said 1st path | route. If a plurality of light collection portions are formed in the first path, it is easy to apply to a solar heat utilization system that discretely collects sunlight at a plurality of locations.

  Moreover, this invention can also be caught from the side as a solar heat utilization system. For example, this invention is a solar heat utilization system, Comprising: You may provide one of said heat receiving apparatuses and the reflective mirror which condenses sunlight to the said to-be-condensed part. Since the heat receiving device suppresses heat radiation from the portion where the sunlight hits among the paths installed in the portion where the sunlight is collected, a solar heat utilization system is constructed by combining the heat receiving device with a reflecting mirror. Thus, a system with high heat recovery efficiency can be formed.

  The said heat receiving apparatus and solar heat utilization system can suppress the heat radiation from the part which sunlight strikes among the paths of the working fluid installed in the part where sunlight condenses.

FIG. 1 is an example of a perspective view of a heat receiving device according to an embodiment of the present invention. FIG. 2 is an example of a diagram illustrating an internal structure of the heat receiving device. FIG. 3 is an example of a cross-sectional view of each part of the heat receiving device. FIG. 4 is an example of a diagram illustrating a moving state of the working fluid, sunlight, and heat inside the heat receiving device. FIG. 5 is an example of a diagram illustrating an application example in which a heat receiving device is applied to a solar heat utilization system. FIG. 6 is an example of a view of the solar heat utilization system as viewed from above. FIG. 7 is an example of a diagram showing a linear Fresnel-type solar heat utilization system. FIG. 8 is an example of a view of the solar heat utilization system as viewed from above. FIG. 9 is an example of a graph showing a change in light collection energy during the daytime in the summer solstice for the two types of solar heat utilization systems of the trough type and the application example described above. FIG. 10 is an example of a graph showing a change in light collection energy during the daytime in the winter solstice for the two types of solar heat utilization systems of the trough type and the application example described above. FIG. 11 is an example of a graph showing a change in light collection energy during the day for two types of solar heat utilization systems of the linear Fresnel (LF) type and the application example described above. FIG. 12 is an example of a diagram showing a modification of the solar heat utilization system. FIG. 13 is an example of a graph showing a change in light collection energy during the day for the two types of solar heat utilization systems of the application example and the modification example. FIG. 14 is an example of a diagram illustrating a reference example of the heat receiving device. FIG. 15 is an example of a diagram illustrating an internal structure of a heat receiving device according to a reference example.

  Hereinafter, embodiments of the present invention will be described. Embodiment shown below is an example of embodiment of this invention, and does not limit the technical scope of this invention to the following aspects.

  FIG. 1 is an example of a perspective view of a heat receiving device according to an embodiment of the present invention. The heat receiving device 1 is obtained by covering a tube material 2 with a heat insulating material 3, and has a rod-like form as shown in FIG. At one end of the heat receiving device 1 (the end on the near side in FIG. 1), an inlet 4 through which the working fluid flowing through the heat receiving device 1 flows and an outlet 5 through which the working fluid flows out are provided. As the working fluid, various heat transport media such as air, carbon dioxide, oil, and steam can be applied. The other end (the end on the back side in FIG. 1) of the heat receiving device 1 is covered with a heat insulating material 3.

  FIG. 2 is an example of a diagram illustrating the internal structure of the heat receiving device 1. FIG. 3 is an example of a diagram showing a cross section of each part of the heat receiving device 1. As shown in FIG. 2 and FIG. 3B, the inside of the tube material 2 is divided into two vertically by a partition plate 6 extending along the longitudinal direction of the tube material 2, and the working fluid is contained in the heat receiving device 1. Forms a two-stage distribution channel in which upper and lower circulate. As shown in FIGS. 2 and 3A, the first path 7 formed on the lower side of the two upper and lower paths formed inside the heat receiving apparatus 1 communicates with the outlet 5. The second path 8 formed on the upper side communicates with the inflow port 4. Further, the partition plate 6 communicates the first path 7 and the second path 8 on the other end side of the heat receiving device 1. Therefore, the working fluid that has passed through the second path 8 and turned back at the end of the pipe member 2 flows into the first path 7 formed on the lower side. The working fluid that has flowed into the first path 7 flows out from the outlet 5. The working fluid flowing in from the inlet 4 flows through the second path 8 formed on the upper side.

  In the middle of the first path 7, a plurality of light collection portions 9 on which sunlight is collected are formed. The condensing portion 9 is a semicircular tube plate 10 and a tube plate 10 that are arranged so as to block the first path 7 before and after the open portion of the tube material 2 partially formed in the middle of the first path 7. It is formed by the thin tube 11 joined to. As shown in FIG. 2 and FIG. 3 (C), the heat insulating material 3 covering the tube material 2 has an opening 12 for applying sunlight to the light collection portion 9 in the first path 7. It is provided at intervals at a plurality of locations along the flow direction, and enables the sunlight to be focused on the light collecting portion 9. A large number of thin tubes 11 are arranged in parallel in the opening 12. Therefore, the narrow tube 11 directly receives sunlight incident from the opening 12. For example, when the narrow tube 11 has a diameter of 300 mm and eight thin tubes 11 are juxtaposed, the horizontal width of the partition plate 6 and the tube plate 10 and the inner diameter of the tube material 2 are set to about 3000 mm. In this case, if the average temperature of the working fluid flowing into the second path 8 is about 300 ° C. and the temperature near the light collecting portion 9 is about 1000 ° C., the average of the working fluid flowing out from the first path 7 The temperature can be about 600 ° C. When the operating temperature of each part of the heat receiving device 1 is set in this way, the thickness of the heat insulating material 3 is preferably about 200 mm although it depends on the material.

  FIG. 4 is an example of a diagram illustrating a moving state of the working fluid, sunlight, and heat inside the heat receiving device 1. The first path 7 and the second path 8 are each formed by a partition plate 6 that partitions the inside of the pipe material 2 into two along the longitudinal direction of the pipe material 2. Therefore, the second path 8 is in a positional relationship parallel to the first path 7 with the partition plate 6 in between, and passes behind the first path 7 with the partition plate 6 in the opening 12. It is in the state formed as follows. The working fluid flows into the second path 8 from the inlet 4 arranged on one end side of the pipe material 2, and the partition plate 6 is interrupted near the other end side of the pipe material 2, thereby causing the first path 7 and the second path to flow. Flows into the first path 7 from the portion communicating with the path 8 and flows out from the outlet 5. Therefore, the working fluid flows so as to face each other with the partition plate 6 interposed therebetween.

  Since the condensing part 9 forms a cavity in a portion surrounded by the two tube plates 10, in the cavity, the radiant heat transfer from the thin tube 11 and the natural convection of the air lead to the outside from the opening 12. There is heat dissipation. However, the heat receiving apparatus 1 according to the present embodiment is formed so that the second path 8 passes behind the first path 7 with the partition plate 6 interposed between the openings 12. That is, the partition plate 6 forming the second path 8 is exposed in the opening 12. Therefore, the working fluid flowing through the second path 8 recovers the heat around the light collection portion 9 in the process of passing through the opening 12. In addition, the working fluid flowing through the second path 8 narrows in the process of passing through the tube plate 10 and flowing into the narrow tube 11, and the flow rate is increased in the narrow tube 11, so that heat transfer is improved and the opening portion is opened. Twelve heat is effectively transferred to the working fluid. For this reason, if it is the heat receiving apparatus 1 which concerns on this embodiment, the thermal radiation to the exterior from the opening part 12 inevitably formed in order to shine sunlight on the to-be-condensed part 9 will be suppressed as much as possible. The working fluid that circulates in the second path 8 is preheated by the heat recovered from the vicinity of the light collecting unit 9 in the process of passing through the opening 12, thereby increasing the heat recovery efficiency of the entire heat receiving device 1.

  In addition, although the said heat receiving device 1 employ | adopts the external appearance columnar form which has the minimum surface area and is excellent also in the workability of the heat insulating material 3 and protective covers, in order to suppress the amount of heat radiation, the heat receiving device disclosed by this application Is not limited to such a form. For example, the tube 2 may be a rectangular shape (a so-called square tube) or other various forms.

  In the heat receiving device 1, the inlet 4 and the outlet 5 are close to each other. Therefore, for example, by installing a reflux valve or the like for returning all or part of the working fluid from the outlet 5 heated to a high temperature to the inlet 4 side, the inlet 4 having a lower temperature than the outlet 5 side. The operation of preheating the working fluid on the side can be easily performed. However, the heat receiving device 1 disclosed in the present application is not limited to the form in which the inlet and the outlet of the working fluid are close to each other. For example, the inlet and the outlet may be separated from each other.

  The heat receiving device 1 can be manufactured by the following method, for example. That is, in the manufacture of the heat receiving device 1, for example, a tube material having a length and heat resistance performance that conforms to the design specifications such as the amount of heat used by solar heat specified in the solar heat utilization system to which the heat receiving device 1 is applied (the material used as the tube material 2). Therefore, the “base material” is prepared below. The base material to be prepared may be any material as long as it can be the tube material 2, and various pipe-shaped members can be applied. As the base material, for example, materials using various materials having heat resistance such as stainless steel (SUS) and Alloy 800H are applicable.

After preparing such a base material, the base material is divided in half along the longitudinal direction, abutted against the partition plate 6, welded at both ends thereof, and the working fluid before being heated by sunlight passes. Manufactures a half-moon shaped pipe. A pair of meniscuses corresponding to the tube plate 10 is prepared in a portion corresponding to the opening 12, and holes through which the working fluid passes are provided at both ends of the narrow tube 11 corresponding to the length of the cavity in the opening 12. After welding 11, the meniscus is welded to the partition plate 6 of the above-described sectional meniscus pipe through which the working fluid before being heated by sunlight passes. And the circular opening used as the opening part 12 is created in the other member produced when the base material is divided into halves, and the pipe having the half-moon shape in cross-sectional view through which the working fluid before being heated by sunlight passes is formed. By welding all around, the base material is returned to the state of the circular tube before being divided in half along the longitudinal direction. Thereafter, a hemispherical member that closes one end of the base material is welded all around. Further, a disk-shaped member provided with two circular openings corresponding to the inlet 4 and the outlet 5 is welded to the other end of the base material all around. In addition, each meniscus welded to the partition plate 6 may be attached to the partition plate 6 at a time in a state of being attached to the thin tube 11 and being unitized. Moreover, the thin tube 11 may be welded in a state where it abuts on the meniscus, or may be welded by expanding the diameter of the end of the thin tube 11 while being inserted through the hole of the meniscus. The welding location may be on either the front side or the back side of the meniscus through which the narrow tube 11 is inserted.

  The heat receiving device 1 can be manufactured by, for example, the above method, but the heat receiving device disclosed in the present application is not limited to the one manufactured by such a method. The heat receiving device disclosed in the present application may be manufactured by a method other than the above.

  FIG. 5 is an example of a diagram illustrating an application example in which the heat receiving device 1 is applied to a solar heat utilization system. FIG. 6 is an example of a view of the solar heat utilization system 50 as viewed from above. The broken line shown in FIG. 5 shows sunlight. The said heat receiving apparatus 1 is suitable with respect to what concentrates sunlight to a specific location discretely like the solar-heat utilization system 50 which concerns on this application example, for example.

  In the existing solar heat utilization system, what is called a trough shape, a linear Fresnel (LF) shape, a tower shape, or a dish shape is generally known as a mechanism for efficiently collecting sunlight. Each has a tracking mechanism for solar operation, and has a morphological feature based on the shape recalled from the name. FIG. 7 is an example of a diagram illustrating a linear Fresnel-type solar heat utilization system 100. Moreover, FIG. 8 is an example of the figure which looked at the solar-heat utilization system 100 from the top. The solar heat utilization system 50 according to the application example is very similar in shape to the linear Fresnel solar heat utilization system 100, but differs in the following points.

  For example, with respect to the structure of the reflecting mirror, the linear Fresnel-type solar heat utilization system 100 shown in FIGS. 7 and 8 has a large number of long, single-mirror reflecting mirrors 101 extending in the north-south direction, whereas FIG. In the solar heat utilization system 50 according to the application example shown in FIG. 6, a large number of small reflecting mirrors 51 are arranged.

  Further, regarding the arrangement of the heat receiving tubes (heat receiving devices), the linear Fresnel-shaped solar heat utilization system 100 arranges the heat reception tubes 102 in parallel with the reflector 101 along the north-south direction, whereas the solar heat utilization system 50 according to the application example described above. Arrange | positions the heat receiving apparatus 1 so that a longitudinal direction may turn into an east-west direction. That is, in the solar heat utilization system 50 according to the application example, the heat receiving device 1 is arranged so that the longitudinal direction of the heat receiving device 1 is orthogonal to the longitudinal direction of the reflecting mirror 51. Therefore, the solar heat utilization system 50 according to the application example can be referred to as a “cross linear condensing type”, for example.

  Further, regarding the heat receiving pipe (heat receiving apparatus), the linear Fresnel-type solar heat utilization system 100 collects sunlight over the entire length of the heat receiving pipe 102, whereas the solar heat utilization system 50 according to the application example described above is The sunlight is discretely collected on the heat receiving device 1 by the number equal to the number of arrangement rows of the reflecting mirrors 51.

The solar heat utilization system 50 according to the above application example has a number of small reflecting mirrors 51 and has the following characteristics because sunlight is discretely collected on the heat receiving device 1. That is, since the solar heat utilization system 50 according to the application example includes a large number of small reflecting mirrors 51, it is possible to reduce the size and weight of devices that track the sun.

  In addition, the solar heat utilization system 50 according to the application example described above includes a large number of small reflecting mirrors 51 and can also track the sun in the north-south direction. Can be demonstrated. This feature is particularly noticeable in the winter solstice. In the winter solstice, the height of the sun as seen from the ground is lowered, but the solar heat utilization system 50 according to the application example can be moved in the row direction (north-south direction) of each reflecting mirror 51. The incident angle of sunlight can be made substantially orthogonal to the longitudinal direction of the heat receiving device 1. Therefore, by adjusting the angles of the reflecting mirrors 51 so that the sunlight is radiated to the heat receiving device 1, high light collecting performance can be achieved not only in the summer solstice but also in the winter solstice. FIG. 9 is an example of a graph showing a change in light collection energy during the daytime in the summer solstice for the two types of solar heat utilization systems of the trough type and the application example described above. FIG. 10 is an example of a graph showing the change in light collection energy during the winter solstice for the two types of solar heat utilization systems of the trough type and the application example described above. As is clear when comparing the graph of FIG. 9 and the graph of FIG. 10, it can be seen that the solar heat utilization system 50 according to the application example exhibits high light collection efficiency in both the summer solstice and the winter solstice. It can be seen that the condensing efficiency is particularly high in the winter solstice. Such an effect of the above application example becomes more prominent as the north latitude is higher, and the difference in light collection efficiency is larger than in other methods.

  Moreover, since sunlight is condensed discretely, the heat receiving device 1 with relatively little heat dissipation can be used, and as a result, the heat receiving efficiency is high. FIG. 11 is an example of a graph showing a change in light collection energy during the day for two types of solar heat utilization systems of the linear Fresnel (LF) type and the application example described above. As is clear from the graph of FIG. 11, the solar heat utilization system 50 of the above application example has a higher peak of collected energy than the linear Fresnel solar heat utilization system 100. Although it is undeniable that various factors have an influence on this reason, since the heat receiving device 1 is provided with the heat insulating material 3, heat radiation is suppressed and the linear Fresnel type solar heat utilization system 100 is provided. It is presumed that the working fluid flows in a temperature region higher than that of the heat receiving pipe 102, thereby exhibiting high light collecting energy.

  The solar heat utilization system 50 to which the heat receiving device 1 is applied may be modified as follows, for example. FIG. 12 is an example of a diagram showing a modification of the solar heat utilization system 50. The solar heat utilization system 50 according to this modification is different in the arrangement of the reflecting mirrors 51. That is, in the solar heat utilization system 50 according to the application example, the reflecting mirrors 51 in each row are arranged at equal intervals. However, in the solar heat utilization system 50 according to the application example described above, for example, as illustrated in FIG. 12, the reflecting mirrors 51 are arranged so that the interval between the reflecting mirrors 51 increases according to the distance from the heat receiving device 1. Good. As each reflecting mirror 51 is separated from the heat receiving device 1, the elevation angle of the heat receiving device 1 with respect to the ground surface becomes smaller, and the adjacent reflecting mirror 51 is likely to be an obstacle to reflected light. However, as shown in FIG. 12, if the reflecting mirrors 51 are arranged so that the interval between the reflecting mirrors 51 is widened according to the distance from the heat receiving device 1, the adjacent reflecting mirrors 51 are unlikely to become an obstacle to the reflected light. Therefore, the peak of the collected energy can be increased.

  FIG. 13 is an example of a graph showing a change in light collection energy during the day for the two types of solar heat utilization systems of the application example and the modification example. As is apparent from the graph of FIG. 13, when the solar heat utilization system 50 according to the application example is modified and the reflecting mirrors 51 are arranged so that the interval between the reflecting mirrors 51 increases according to the distance from the heat receiving device 1, The peak of the collected energy can be further increased.

FIG. 14 is an example of a diagram illustrating a reference example of the heat receiving device. As a heat receiving device applicable to the solar heat utilization system 50, for example, a heat receiving device 20 as shown in FIG. 14 is also conceivable. FIG. 15 is an example of a diagram illustrating an internal structure of the heat receiving device 20 according to the reference example. The heat receiving device 20 according to the present reference example takes a form in which the working fluid flowing in from one end side in the longitudinal direction passes through the thin tube 31 and flows out from the other end side in the longitudinal direction. In the case 22 of the heat receiving device 20, openings 32 for applying sunlight to the thin tubes 31 inside the case 22 are discretely formed. The thin tube 31 directly receives sunlight incident from the opening 32.

  As a heat receiving device applicable to the solar heat utilization system 50, for example, such a heat receiving device 20 is also conceivable. However, the heat receiving device 20 according to the present reference example does not have means for preheating the working fluid and suppressing heat radiation from the opening 32 to the outside, unlike the heat receiving device 1 according to the above embodiment. In this respect, the heat receiving device 1 according to the above-described embodiment has means for preheating the working fluid and suppressing heat radiation from the opening 32 to the outside. Therefore, compared with the heat receiving device 1 according to the present reference example, the heat recovery efficiency. Is excellent.

1, 20 ... Heat receiving device; 2 .... Tube material; 22. Case; 3 ... Heat insulation material ... 4. Inlet port; 5 .... Outlet port; 6 .... Partition plate; 8 .. Second path; 9 .. Condensed part; 10. .. Tube plate; 11, 31 .. Narrow tube; 12, 32 .. Opening part; ..Reflector; 102

Claims (6)

A first path through which the working fluid flows;
A heat-insulating material that includes the first path, and is provided with an opening for applying the sunlight to a light-collected part in which sunlight is collected in the first path;
A path of a working fluid contained in the heat insulating material together with the first path, and a second path through which a working fluid for recovering heat around the light collection portion passes through the opening; equipped with a,
The condensing portion is formed by a thin tube disposed in an open portion of a tube material partially formed in the middle of the first path.
Heat receiving device. The second route is connected to the first route;
The heat receiving device according to claim 1. The second path is arranged in parallel with the first path, and is formed so as to pass behind the first path in the opening.
The heat receiving device according to claim 1 or 2. The first path and the second path are each formed by dividing the inside of the pipe material into two along the longitudinal direction,
The object light collecting portion is formed by said capillary to be joined to the semi-circular tube plate and the tube plate arranged to intercept the first path before and after the pre KiHiraki release portion,
The heat receiving device according to any one of claims 1 to 3. The light collection part is formed in a plurality of locations in the first path.
The heat receiving device according to any one of claims 1 to 4. The heat receiving device according to any one of claims 1 to 5,
A reflecting mirror for condensing sunlight on the light collection part,
Solar heat utilization system.

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