JPS608656A - Solar heat collector - Google Patents

Abstract

PURPOSE:To effectively utilize the heat of incident solar rays, by providing the secondary fluid passages in the position where the solar heat is converged by the reflective surface of a heat collection board, as well as to form a heat collection board, to which the primary fluid passages are fitted, on a reflective board in a solar heat collector. CONSTITUTION:The primary fluid passage 1 comprises copper pipes 5, 6, 7 and 8 of small diameter which are arranged in close contact with the back of a heat collection board 2. The secondary fluid passage 4 consists of five copper pipes 9, 11, 12, 13 and 14 of small diameter, coated with black painting, juxtaposed in the position of a space which is partitioned by an imaginary partition surface (a), at regular intervals between them. Out of these pipes, the pipe 9 is provided abutted on a reflective surface 3. With such an arrangement, the reflective heat that was conventionally disperesed in vain is actively converged and can be utilized for heating of the secondary fluid passages 4. In addition, most part of the solar heat reflected by the reflective surface 3 can be absorbed into any one of the pipes 9, 11, 12, 13 and 14, though the angle of incidence of the solar rays is changed by the change of season and time.

Description

DETAILED DESCRIPTION OF THE INVENTION (a) Industrial Application Field The present invention relates to a solar heat collector mainly used as a solar heat collecting element in a solar water heating system.

(b) Conventional technology Recently, there has been a strong demand for the use of natural energy from the standpoint of effective resource utilization, and as part of this, various so-called solar hot water systems have been developed that use solar heat to heat water at 11 liters. It has become widely popular.

By the way, solar heat collectors used in this type of system include, for example, those in which a fluid passage through which a fluid to be heated is circulated is attached to a flat heat collecting plate that absorbs solar heat. Are known.

However, with such a configuration, a part of the solar energy incident on the heat collecting plate is discarded without being absorbed by the heat collecting plate due to the heat collecting plate 1, etc., and the absorbed heat is also discarded. It will then be transmitted to the fluid within the fluid passageway by conduction.

Therefore, it is impossible to concentrate solar heat in a high density in the fluid passage, and not only does it take time to raise the temperature of the fluid, but also in winter, the fluid temperature reaches a ceiling at a low level, and hot water cannot be used. The problem is that you can't get it.

(c) Purpose of the invention The present invention was made with attention to the above circumstances, and
An object of the present invention is to provide a solar heat collector that can efficiently raise the temperature of a fluid to a high temperature by effectively utilizing incident solar heat.

(d) Construction of the invention In order to achieve the above object, the present invention forms a heat collecting plate attached with a first fluid passage into the shape of a reflecting plate, and collects solar heat by the reflective surface of the heat collecting plate. The present invention is characterized in that a second fluid passage is provided at a position where the fluid is moved.

(e) Examples Hereinafter, one embodiment of the present invention will be described with reference to the drawings.

A first fluid passage 1 is attached to a heat collecting plate 2, and the heat collecting plate 2 is formed into a reflector shape, and a second fluid is provided at a position where solar heat is collected by the reflective surface 3 of the heat collecting plate 2. A passage 4 is provided.

The first fluid passage 1 consists of small diameter copper pipes 5, 6, 7, and 8 disposed in close contact with the back surface of the heat collecting plate 2. Of these pipes, the pipe 5 and the pipe 8 are They are also in close contact with the back surfaces of the respective attached heat collecting plates 2.

The heat collecting plate 2 is made of stainless steel and has a relatively small gutter shape.

The reflective surface 3 is composed of four surfaces 3a, 3b, and 3C13d with different center lines or radii of curvature, and the surface 3a has a center line O.
1, the surface 3b is a curved surface with a radius of curvature R2 centered on the center line 02, and the surface 3C is centered on a virtual dividing surface a that symmetrically divides the reflective surface 3 into two. A curved surface with a radius of curvature R2 centered on the center line 08 which is symmetrical to the center line 02, and the surface 3d is the center line 0 which is symmetrical to the center line O1 with the virtual dividing plane a as the center.
a) Curved surface with a radius of curvature R1 centered at 4.

The second fluid passage 4 is made up of five small-diameter copper pipes 9.1 painted black and arranged in parallel at little intervals at the positions where the virtual dividing plane a partitions the space.
1.12.13.14, of which the pipe 9 is provided in contact with the reflective surface 3.

A heat-receiving device having a stainless steel R4M outer frame 15 and a glass plate 16, in which several sets of the first fluid passage 1, the heat collecting plate 2, and the second fluid passage 4 are closely arranged in parallel is used. an outgoing pipe 18 housed in the box 17 and extending from the inside of the heat receiving box 17 to the outside to guide low-temperature water from a pump (not shown) to the first fluid passage 1 and the second fluid passage 4; A return pipe 19 is provided to return the water heated in the first fluid passage 1 and the second fluid passage 4 to the pump via a heat exchanger (not shown), and each pipe 5 of the first fluid passage 1 is The starting ends of the pipes 9.11.1213.14 of . Note that 21 is a heat insulating material made of glass wool for preventing heat radiation.

The solar heat collector having such a configuration is fixed on a roof or the like with the reflective surface 3 facing in a predetermined direction.

With such a structure, when solar heat is incident on the reflective surface 3, a part of the solar heat is absorbed by the heat collecting plate 2, is reflected in the first fluid passage 1, and is transmitted to each pipe 5 of the fluid passage 1. .6.
7.Heat the water in 8 to raise its temperature. Further, the unabsorbed portion of the solar heat is reflected by the reflective surface 3 and concentrated at a predetermined position, thereby heating the water in the second fluid passage 4 and raising its temperature. The water heated in this manner is sucked into a pump (not shown) and flows to the pump via the return pipe 19 (during this flow, when passing through a heat exchanger (not shown), heat is generated in the heat exchanger (not shown). The exchange is performed, and the water heated in the first fluid passage 1 and the second fluid passage 4 transfers its heat to the heating target and stores the heat.On the other hand,
The heated and heat-exchanged water is supplied to the first fluid passage 1 and the second fluid passage 4 at a low temperature from the pump via the outgoing pipe 18.

In this way, the object to be heated is heated while circulating the water. In this embodiment, the heat collecting plate 2 is formed in the shape of a reflecting plate, and in addition to the conventional first fluid passage 1. 5 arranged in parallel at the position where the virtual dividing plane a partitions the space.
Since the second fluid passage 4 is provided with the small-diameter pipes 9, 11, 12, 13, and 14, the following effects are achieved.

First, the reflected heat, which was conventionally wasted, can be concentrated and used to heat the second fluid passage 4, which increases the heat collection efficiency and raises the temperature of the water to a higher temperature. be able to.

Furthermore, according to this embodiment, even if the angle of incidence of sunlight changes depending on the season or time, most of the solar heat reflected by the reflecting surface 3 is transferred to the pipe 9.11.12.13.14.
Since the reflected heat is absorbed by either of the above, there is less chance of the reflected heat escaping, and the heat collection efficiency is better than that of conventional thick reflector type heat collectors. For example, when the altitude of the sun is low in the morning or evening and the angle of incidence of sunlight is large, solar heat is transferred to the pipe 131.
4 (Figure 5), and when the altitude of the sun is a little higher than that, the angle of incidence becomes smaller and solar heat is mainly absorbed by the pipe 13 (Figure 6).
As the temperature rises, the heat collection position changes, and when the sun is at its mid-south point, the angle of incidence becomes zero, and solar heat is mainly transferred to pipe 1.
1 (Figure 7), most of the reflected solar heat is focused on and absorbed by one or two pipes, so a high heat collection efficiency can always be obtained. The pipe 9 is also heated by conductive heat from the heat collecting plate 2, and a pipe that is directly exposed to sunlight absorbs sunlight to the same extent as a flat pipe. Furthermore, if the accuracy of the reflective surface 3 is not good and distortion occurs in the reflective surface 3, or if the heat collecting plate 2 is deformed due to aging, the solar heat reflected by the reflective surface 3 will be reduced as described above. Since most of the light is collected and absorbed by either pipe, there is no problem that the heat collection performance will deteriorate significantly.

Moreover, even if the heat absorbed by one of the pipes is radiated, most of it is absorbed again by other adjacent pipes, so less heat is radiated to the outside.
There is no need to surround the pipe with a glass tube to prevent heat radiation, as is the case with conventional reflector type pipes (this can reduce manufacturing costs accordingly).

In addition, since the heat collecting plate 2 can be made smaller than that of a conventional reflector plate, the heat collecting plate 2 and the second fluid passage 4 can be arranged with high density, and the heat collection efficiency can be increased accordingly. At the same time, it is possible to make the heat collector more compact.

Note that the present invention is of course not limited to the embodiment described in O1j, and the fluid circulation method is not limited to a forced circulation method using a pump, but a natural method that uses fluid convection to naturally circulate the fluid. It may also be of a circulation type.

Further, the number of pipes in the first fluid passage is not limited to four, and the number of pipes in the second fluid passage is not limited to five.

Further, the pipe is not limited to being made of copper, but may be made of a material with good thermal conductivity.

Furthermore, the curved shape of the reflective surface is not limited to that of the embodiment described above.

Further, the heat collecting plate is not limited to stainless steel 01H, and may be a copper plate with one surface mirror-plated, for example.

The shape of the pipe is limited to a circular cross section; for example, the pipe may have a circular cross section, a triangular cross section, or the like.

Further, the arrangement position of the pipe of the second fluid passage is not limited to the position where the virtual dividing plane partitions the space, but may be arranged at a position where the solar heat reflected by the reflective surface is substantially concentrated.

Furthermore, the fluid to be circulated within the pipe is not limited to water, but may also be a refrigerant such as chlorofluorocarbon gas.

(F) Effects of the Invention As detailed above, according to the present invention, the fluid in the first fluid passage attached to the heat collecting plate is heated by the solar heat absorbed by the heat collecting plate. In addition, the heat collecting plate is formed into a reflector shape to actively concentrate solar heat reflected on the surface of the heat collecting plate, and the concentrated heat heats the fluid in the second fluid passage. As a result, most of the incident solar thermal energy can be effectively used to raise the temperature of the fluid. Moreover, since solar heat is concentrated in the second fluid passage at a high density, the fluid in the passage can be quickly heated with high efficiency. Therefore, it is possible to efficiently raise the temperature of the fluid to a high temperature, and it is possible to provide a solar heat collector that can be put to practical use even in winter.

[Brief explanation of the drawing]

The drawings show one embodiment of the present invention, with FIG. 1 being a plan view and FIG.
The figure is a sectional view taken along the line T'' in FIG. 1, FIG. 3 is a sectional view taken along the 1ft-ffl line in FIG. 1, and FIG. FIG. 7 is an explanatory diagram of the action. 1...First fluid passage 2...Heat collecting plate 3...Reflecting surface 4...Second fluid passage 5.6.7.8...Pipe 9.11.12.13. 14... Pipe a... Virtual split plane agent Patent attorney Hiroshi Akazawa Figure 1 ■ Figure 2 Figure 5 Figure 3 Figure 4 Figure 6 Figure 7

Claims (2)

[Claims] (1) The heat collecting plate with the first fluid passage attached thereto is formed into the shape of a reflecting plate, and the second fluid passage is provided at a position where solar heat is collected by the reflective surface of the gas S heating plate. solar heat collector. (2) The second fluid passage is made up of several small diameter pipes arranged in parallel at positions substantially along a virtual dividing plane that symmetrically divides the reflective surface of the heat collecting plate into two. A solar heat collector according to claim 1, characterized in that: