JPH0115784B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a solar heat storage tank that is improved so as to be able to effectively store and effectively extract heat collected from the sun.

When collecting solar heat and supplying it to a load,
How to absorb changes over time in the amount of heat collected due to changes in the amount of solar radiation is a fundamental issue in increasing the effectiveness of solar heat utilization systems. The most common measure is to once return water from a heat collector to a heat storage tank, where it mixes or separates hot and cold water and returns it to the heat collector or supplies it to the load. In this case, in order to increase the amount of heat storage, improve the heat storage characteristics, and increase the heat collection efficiency and the amount of heat supplied to the load, a stratified flow is created in the tank using the density difference based on the temperature difference of the circulating water. Ideally, it should be formed.

The present invention was made for the purpose of effectively forming a stratified flow of this circulating water in the tank, and as shown in the embodiment of the drawings, the water return pipe 2 from the solar heat collector 1 is Flow path control valves 4a, 4b that change the flow path according to the water temperature are inserted, and a plurality of branch pipes 5a, 5b, 5c, which are branched by the flow path control valves 4a, 4b, are placed on the upper and lower sides of the heat storage tank 6. Rectifying means 7a to 7a are connected to the heat storage tank 6 at intervals and are opened from the side surface of the heat storage tank 6 so that return water is discharged horizontally into the tank, and rectify and deflect this horizontal discharge flow in the vertical direction. 7
(Fig. 1), or the branch pipes 5a, 5b, 5c are installed horizontally in the heat storage tank 6 at intervals vertically.
8b, 8c, and these discharge pipes 8a, 8b, 8
c) A large number of discharge ports are provided on the circumferential surface of the tank, and rectifying means 7a to 7c for rectifying the discharge flow from the discharge ports in the vertical direction are installed in the tank (Fig. 5). It is.

In the embodiments shown in FIGS. 1 and 5, 9 represents a load such as a refrigerator or an AHU, and 10 represents a load such as a hot water supply facility. Reference numeral 11 denotes a make-up water facility, which replenishes the system with an amount of water corresponding to the amount discharged from the system.

The flow path control valves 4a and 4b inserted into the water return pipe 2 have a structure that is a switching valve that switches the flow path depending on a known temperature. For example, it is convenient to use a mechanism that opens and closes any two valve ports of a three-way valve by utilizing the volume expansion caused by the melting of wax sealed in a capsule. When the temperature reaches the melting temperature of the wax, the rotor installed inside the valve body is rotated to control the opening angle of the two outflow valve ports, and the hot water that has reached a predetermined temperature is
It is possible to selectively screen into one of the two branches. Two of these known flow path control valves are utilized in the illustrated embodiment. In the first flow path control valve 4a, when the hot water that has passed through the solar heat collector 1 is _T1 or more, it is screened into a branch path 5a, and when it is less than _T1 , it is passed through the second flow path control valve 4b. Sift this. In _the second flow path control valve 4b, when the water temperature is below T ₁ but above T 2 , the water is screened into the branch path 5 b , and when it is below T ₂ , it is screened into the branch path 5 c. As a result, high-temperature water of T ₁ or more flows into the branch road 5a.
Medium temperature water of T ₂ or more and less than T ₁ is in b, and in branch road 5c
Low temperature water below T ₂ , where T ₁ >T ₂ , will be screened out.

These branch pipes 5a, 5b, 5c are connected at intervals from above to below the side surface of the heat storage tank 6 in the order of the temperature of the return water flowing through them, and are horizontally connected to the inside of the tank at the connection point. They are either open so as to produce a directional discharge flow (FIG. 1) or connected to horizontal discharge pipes 8a to 8c (FIG. 5).
figure). Therefore, high-temperature water is introduced into the heat storage tank 6 at an upper position, medium-temperature water at the center, and low-temperature water at a lower position.

The rectifying means 7a to 7c, as shown in FIGS. 2 to 4, are comprised of a group of cylinders made up of a large number of short cylinders arranged vertically in a bundle. This layer of bundled cylinders is formed above and below (7a and 7a') the high temperature water introduced into the tank.
They are arranged above and below the medium-temperature water (7b and 7b') and above and below the low-temperature water (7c and 7c') over the entire cross section of the tank. Figure 2 shows one of the layers of the cylinder group.
This is an enlarged view of the section, showing the short cylinders 13 arranged vertically and in contact with each other. Fig. 3 is a plan view showing another example of a group of cylinders, in which the short cylinders 13 An example is shown in which the two are held vertically and fixed to each other by horizontal support rods 14. In the example shown in Figure 2, the amount of water passing through the inside of the cylinder 13 is greater than the amount passing outside the cylinder, and by passing through the inside of the cylinder, a rectifying effect in the vertical direction can be obtained. In the example, a large amount of air passes both inside and outside the cylinder, and both the inner wall and outer wall of the cylinder 13 provide a rectifying effect in the vertical direction.

In each layer (7a to 7c') of this group of cylinders, the inner diameter of the cylinder 13 is gradually reduced as it moves away from the connection point to the tank of return water, in other words, as it moves away from the tank wall connecting the branch pipe 5. It is recommended that the rectifying resistance be increased by increasing the rectifying resistance. FIG. 4 shows this example, in which a cylinder 13 whose diameter gradually decreases from the branch pipe 5 side to the outflow pipe 15 side is arranged in a heat storage tank 6 having a circular cross section. It shows. Note that the cross section of the heat storage tank 6 does not necessarily have to be circular as shown in FIG. 4, and any cross section shape can be used. The rectifying means 7a to 7c' may be made of a layered body made by arranging short cylinders of the same length on the same horizontal plane with their respective axes in the vertical direction, in addition to the cylinder group in the front row, for example. A rectifying means such as a layered honeycomb structure in which hexagonal short cylinders are aligned with their axes in the vertical direction may be used, and a rectifying means that increases the flow vector in the vertical direction may be used.

By means of the rectifying means 7a to 7c' as described above, high temperature water gathers in the uppermost stage A of the tank, medium temperature water gathers in the middle stage B, and low temperature water gathers in the lowermost stage D, thereby achieving stratified heat storage. The low-temperature water in the lowest stage D is sent to the solar heat collector 1 by the circulation pump 16, where it collects heat again and is returned to the heat storage tank 6 while being distributed according to its temperature.

On the other hand, the high temperature water in the upper stage A is taken out from the water pipe 15a and sent to the load 9, and then returned to the middle and lower stage C zone from the return pipe 17a. The medium-temperature water in the middle stage B is taken out from the water pipe 15b and sent to the other load 10, and then sent to the middle and lower stage C from the return pipe 17b.
band. Due to the difference in density depending on the temperature, the return water from the load returned to the zone of the middle and lower stage C rises to the zone of the middle stage B through the rectifiers 7b' and 7b in the high-temperature part, and the rectifier 7c in the low-temperature part. ' and then descends to the lowest band D. In this way, several flows flow into and out of the heat storage tank 6, but due to the action of the rectifying means 7a to 7c' and the flow path control valves 4a and 4b, the lower low-temperature layer is kept in the tank. A desirable stratification is formed from the temperature to the upper high temperature layer.

In the embodiment shown in FIG. 5, discharge pipes 8a to 8c are added to the embodiment shown in FIG. Stratification can be formed. 6 and 7 show an example of this discharge pipe 8, and as shown in the figure, a large number of upward and diagonally upward discharge ports 18 are provided on the circumferential surface of this discharge pipe 8. By arranging the discharge pipe 8 horizontally within the tank as shown in FIG. 5, the returned water can be uniformly discharged over the width of the tank. In this case, the diameter of the discharge ports 18 may be changed according to the flow direction of the return water in the discharge pipe 8, or the number of ports may be changed so that the return water is uniformly discharged from each discharge port 18. In this case, it is not necessarily necessary to take measures to make the flow resistance of the rectifying means 7 uniform (measures to change the cylinder diameter as in the example shown in FIG. 4).

As described above, the present invention solves the conventional fundamental problem of reducing the efficiency of solar systems due to heat fluctuations by forming stratified heat storage by using the rectifying means and flow path control valve as described in detail. This effectively solves the problem, and provides a solar heat utilization system that exhibits desirable effects such as improved heat storage characteristics, increased heat collection, and uniform heat supply.

[Brief explanation of drawings]

Fig. 1 is an equipment layout system diagram showing one embodiment of the present invention, Fig. 2 is a partially enlarged perspective view showing one embodiment of the rectifying means, and Fig. 3 is a partial plan view showing another embodiment of the rectifying means. , FIG. 4 is a plan view showing another embodiment of the rectifying means, FIG. 5 is an equipment layout system diagram showing another embodiment of the present invention, and FIG. 6 is a partially enlarged perspective view showing one embodiment of the discharge pipe. 7 are cross-sectional views of the discharge pipe. 1...Solar heat collector, 2...Return water pipe, 4...
Flow path control valve, 5...branch pipe, 6...
Heat storage tank, 7... Rectification means, 8... Discharge pipe, 9...
Load, 10...Load, 13...Cylinder, 18...Discharge port.

Claims (1)

[Claims] 1. A flow path control valve that changes the flow path according to the water temperature is inserted into the water return pipe from the solar heat collector,
A plurality of branch pipes branched by this flow path control valve are connected to the side of the heat storage tank at intervals vertically, and the return water is discharged horizontally from the side of the heat storage tank into the tank. The end of each branch pipe is opened, and a layered flow straightening means is formed by arranging a large number of short cylinders with open upper and lower ends on the same horizontal plane with their respective axes in the vertical direction. A solar heat storage tank installed horizontally above and below the opening. 2 Insert a flow path control valve that changes the flow path according to the water temperature into the return water pipe from the solar heat collector,
A plurality of branch pipes branched by this flow path control valve are connected to a discharge pipe installed horizontally at vertical intervals in the heat storage tank, and a large number of discharge pipes are arranged on the circumference of this discharge pipe. A heat storage tank for solar heat utilization, which is provided with an outlet and is equipped with a rectifying means for vertically rectifying the flow discharged from the outlet.