JPS5912254A - Solar heat collector - Google Patents

Abstract

PURPOSE:To substantially equalize fluid resistances in each row easily and speedily, by a method wherein a pipe joint for a heat collector and a heat-transmitting medium pipe is provided with a threaded hole communicated with a passage provided in the joint, and a flow rate regulating plug for changing the cross-sectional area of the passage in the joint is engaged into the hole. CONSTITUTION:A union 8 of the pipe joint 6 for connecting a header 7 for the heat collectors 4 and the heat-transmitting medium pipe 5 to each other is provided with the threaded hole 10 communicated with the passage 9 provided in the union 8, the flow rate regulating plug 11 for changing the cross-sectional area of the passage 9 is engaged into the hole 10. The plug 11 is provided with a pressure-measureing hole 12 into which a pressure gage can be fitted. Flow rate regulating plugs 11 of various different lengths are provided, and one of them is selected in accordance with the working situation. Namely, one of the plugs 11 which does not substantially change the cross-sectional area of the passage in the union 8 is used for the joints 6 for connecting parts B1', B2', and other appropriate plugs 11 are used for connecting parts B3', B4' and B5' so that a fluid resistance corresponding to one heat exchanger 4 is imparted to the part B3' while a fluid resistance corresponding to two heat exchangers 4 is imparted to each of the parts B4' and B5', whereby the fluid resistance in each row can be substantially equalized. When desired, the fluid pressure in each row is measured by utilizing the pressure- measuring holes 12 to confirm whether or not the fluid resistance is uniform and to inspect the performance of the heat exchanger 4 in each row.

Description

DETAILED DESCRIPTION OF THE INVENTION (A) Industrial Application Field The present invention is directed to a method in which a plurality of heat collectors are arranged in two or more rows, and each of these rows is connected to a heat storage tank by a heat medium piping, an outgoing main pipe and a return main pipe. This relates to a solar heat collector that collects solar heat by connecting in parallel with the heat carrier and forming a circulation system for the heat medium.In particular, the fluid resistance of each row is approximately equal to improve heat collection efficiency. It is something.

(B) Background Art In solar heat collectors, it is an important issue to make the distribution of water uniform to each row of heat collectors. If the flow is divided unevenly, the temperature rise gradient in each row of heat collectors will vary greatly.
While the temperature at the outlet where the flow rate is low rises very high, the temperature at the outlet where the flow rate is high does not rise much, resulting in a decrease in heat collection efficiency. In addition, if the flow velocity in the heat collecting pipe is extremely reduced due to poor diversion, the heat transfer coefficient within the pipe will decrease, affecting the heat collection efficiency, and conversely, areas where the flow velocity is high will accelerate the progress of corrosion within the pipe. . Furthermore, if the minimum flow rate is not ensured, smooth air removal will not be possible and the heat medium will boil and evaporate, resulting in a dangerous situation.

Figures 1 and 2 show conventional solar heat collectors, where (1) and (2) are the forward and return main pipes connected to the heat storage tank (3), respectively, and (4) is the heat collector. (5) is a heat medium pipe.

In the case shown in Figure 1, the number of heat collectors (4) in each row is the same, so there is no big difference in the flow rate in each row, but the length of the piping in each row as seen from the heat storage tank (3) is made uniform. Return to main (2)
) to the outgoing main pipe (1), which requires an extra length of the main pipe with a large diameter, resulting in an increase in cost.

What is shown in Fig. 2 is an example in which the number of heat collectors (4) in each row is limited depending on the conditions of the installation location, and in this case,
The fluid resistance of each column is significantly different, and there is a possibility that a shunt failure may occur. Therefore, while performing reverse return piping,
Flow rate adjustment pulp (not shown) was attached to parts 1, A2, and A3 to adjust the flow rate, but in this method, the flow rate adjustment pulp was extremely expensive and it was difficult to accurately adjust the flow rate. , which had the drawback of being extremely time-consuming. That is, while the flow rate is being adjusted for one pulp, the flow rate for other columns changes.

In addition, instead of the flow rate adjusting pulp, it has been proposed to insert a component such as an orifice having a predetermined fluid resistance into the heat medium pipe (5), but even with this method, the parts and the heat medium pipe (5) are inserted into the heat medium pipe (5). ), which involved work and required parts to be attached using piping joints, which increased costs and was time-consuming.

(C) Technical Problems of the Invention The present invention is intended to eliminate the above-mentioned drawbacks of the prior art at once, and is extremely simple and quick.

B) Main Points of the Invention The present invention is characterized by providing screw holes that communicate with the flow passages inside the joints in a small number of the piping joints between the heat collector and the heat medium piping in each row. A flow rate adjustment plug that changes the flow path area inside the joint is screwed into the screw hole to make the fluid resistance of each row approximately equal. By preparing various flow rate adjustment plugs that can provide fluid resistance equivalent to the resistance, and selecting the appropriate flow rate adjustment plug according to the construction situation at the site and screwing it into the screw hole of the piping joint, the fluid resistance of each row can be adjusted. To ensure uniformity of

(e) Embodiment of the invention The flow rate adjustment plug is provided with a pressure measurement hole passing through it,
This is screwed into a screw hole of a piping joint that connects the heat collector and heat medium piping on the return main pipe side. In this way, by inserting a pressure gauge into the pressure measurement hole and measuring the fluid pressure in each row, the flow rate in each row can be determined from the pressure resistance diagram, and whether the fluid resistance is equalized or not. It is easy to check the performance of each row of heat collectors (heat collection amount = flow rate x temperature difference between inlet and outlet) at any time.

(f) Embodiment of the Invention FIGS. 3 and 4 each show an embodiment of the present invention, and parts common to those shown in FIGS. 1 and 2 are designated by the same reference numerals. In Figures 3 and 4, the difference from the conventional one is that the main return pipe (2) is connected to the heat storage tank (3) at the shortest distance.
), and the reverse return piping is abolished, and the connection part (B1) or B5) between the heat collector (4) on the return main pipe (2) side of each row and the heat medium piping (5) and (B7)
or B5<) to have the structure shown in FIGS. 5 and 6.

In Figures 5 and 6, (6) is a pipe joint that connects the header (7) protruding from the heat collector (4) and the heat medium pipe (5), and the union (8) is connected to the heat medium pipe (5). (8) is provided with a threaded hole (to) that communicates with the flow path (9), and the threaded hole (
2) Flow rate adjustment plug (b) that changes the area of the flow path (9)
It is provided by screwing them together. Further, the flow rate adjustment plug (b) is provided with a pressure measurement hole (6) that passes through the inside in the axial direction to which a pressure gauge (not shown) can be attached. Pressure measurement hole (6
) has a screw cut on the top and is always connected to a blind plug (
(to) is sealed by screwing. Note that the flow rate adjustment plug (11) is available in various lengths, and is appropriately selected depending on the construction situation at the site.

According to this embodiment, when the number of heat collectors (4) in each row is equal as shown in FIG. By attaching a longer flow rate adjustment plug 0→ to (6) and selecting shorter flow rate adjustment plugs Ql) at the connection part (B2) or B5), the fluid resistance of each row can be approximately equalized. can be converted into on the other hand,
If the number of heat collectors (4) in each row is different as shown in Figure 4, use flow adjustment plugs for the piping joints of connections (B1) and (B2) that hardly change the flow path area in the union. However, the connection part (B3) has one heat collector, the connection part (B4) and (
For B5), by appropriately selecting and using flow rate adjustment plugs to provide fluid resistance equivalent to two heat collectors,
The fluid resistance of each row can be approximately equalized. Since the flow rate adjustment plug (b) is equipped with a pressure measurement hole (6),
At any time, the fluid pressure in each row can be measured and the flow rate can be determined using a pressure-resistance diagram (not shown). This allows you to check whether the fluid resistance is uniform and check the flow rate of the heat collectors in each row. A performance check will be carried out.

Although the flow rate adjustment plug (1]) is screwed together, if the pressure measurement hole (A) is not installed in the flow rate adjustment plug 0η, the piping joint between the heat collector and heat medium piping should be installed on the return main pipe side. It doesn't have to be from . Also, there is no need to attach a flow rate adjustment plug to each piping joint (in short, it is sufficient to attach it to the piping joint of the row in which flow rate adjustment is required).

(G) Effects of the Invention As explained above, the present invention provides a pipe joint between a heat collector and a heat medium pipe with a screw hole that communicates with the flow path inside the joint, and the flow path area inside the joint is set in the screw hole. Since the variable flow rate adjustment plugs are screwed together, the fluid resistance of each row can be made approximately equal, making adjustment work much easier and faster than with conventional pulp operation or connecting parts such as orifices with piping. It is extremely useful because the parts used are inexpensive, the length of the main pipe can be shortened, and the cost of the device can be reduced.

[Brief explanation of the drawing]

Figures 1 and 2 are system diagrams showing an example of a conventional solar heat collector, Figures 3 and 4 are system diagrams each showing an embodiment of the device of the present invention, and Figure 5 is a system diagram of the device of the present invention. FIG. 6 is a perspective view of essential parts of one embodiment, and FIG. 6 is a longitudinal cross-sectional view of the piping joint shown in FIG. 5. (1)... Outgoing main pipe, (2)... Return main pipe, (3)...
... Heat storage tank, (4) ... Heat collector, (5) ... Heat medium piping, (6) ... Piping joint, (9) ... Flow path, (g)
...Screw hole, (11)...Flow rate adjustment plug, (1)...Pressure measurement hole. Fig. 1 Fig. 2 Fig. 3 Fig. 3 Fig. 4 Fig. 5 Fig. 6

Claims (2)

[Claims] (1) A plurality of heat collectors are arranged in two or more rows, and each row is connected in parallel between an outgoing main pipe and a return main pipe connected to a heat storage tank by heat medium piping to form a heat medium circulation system. In the piping joint between the heat collector and the heat medium piping in each row, at least a part thereof is provided with a screw hole that communicates with the flow path inside the joint, and the screw hole communicates with the flow path inside the joint. A solar heat collecting device characterized in that flow rate adjustment plugs that change the road area are screwed together to make the fluid resistance of each row approximately equal. (2) The flow rate adjustment plug shall be provided through the pressure measurement hole, and the flow rate adjustment plug shall be screwed into the screw hole of the pipe joint that connects the heat collector and heat medium pipe on the return main pipe side. A solar heat collecting device according to claim 1, characterized in that: