JPS63238362A - Device for transmitting solar energy over liquid existing in vessel - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION FIELD OF INDUSTRIAL APPLICATION The invention relates, according to the preamble of claim 1, to a device for transmitting solar energy to a liquid present in a container.

BACKGROUND OF THE INVENTION Known devices of the above-mentioned type start from a pot, for example a boiling pot, as the inner part of the collector and the two-walled container for direct evaporation. In this case, the steam loads the vessel from the outside and the resulting condensate is drawn off downwards in the direction of gravity. #l Due to the very good heat transfer during condensation, an excess temperature of the steam of less than 10° C. is sufficient to heat the water to boiling in the pot. However, this known system requires a special container, and a conventional boiling container cannot be used. Furthermore, when circulating, there is a risk that the collector circulation path is contaminated by the unpurified outside of the pot.

Problem to be Solved by the Invention Starting from the known assumptions, the present invention provides a solution that does not require any other extraneous energy to overcome the transport height when utilizing solar energy and does not require any deformation of the container. The object is to obtain a device or a circuit as defined in the preamble of claim 1, which makes it possible to heat a liquid in a conventional container without the need for heating.

Means for Solving the Problem By the way, in order to solve this problem, the present invention proposes the features described in the characteristic part of claim 1. Furthermore,
Particularly advantageous developments of the invention emerge from the features described in one of claims 2 to 4.

According to the invention, however, the heating surface can be immersed in the form of a condenser directly into the liquid to be heated or into the boiling liquid. Thereby, direct heat transfer takes place, and in this case advantageously existing or customary existing containers can be further used. Furthermore, the circuit of the collector itself remains completely closed and no longer needs to be opened when removing the heating container.

This is achieved according to the invention in that the heat source is present directly in the liquid to be heated and can therefore remain retained with low outward losses.

Furthermore, when water is used as a heating medium, problems of overheating in heated fittings no longer occur. Heat transfer to the liquid determines the rate of condensation and thus the flow of heat. The maximum possible temperature can be determined by the system pressure and can therefore be maintained within limits of approximately 20°C.

According to the invention, it is particularly advantageous that the heating medium can be raised above the vessel edge again for being returned from the condenser to the collector, thereby eliminating the need for a constantly operating circulation pump. The circuit according to the invention thus operates without extraneous energy. According to the present invention, this means that n is confined in the flow direction after the condenser.
This is made possible by the exchange cycle of the added air volume with the steam space in the steam conduit as well as in the condenser. Thereby, the condensate from the condenser flows above the vessel edge into JJ4
be transported.

EXAMPLE Next, the present invention will be further explained in detail with reference to FIGS. 1 to 4.

1 to 4 show a solar collector 1 as a heat source, which essentially consists of a light-transparent conduit 2 as a receiver and a condensate return pipe 3 coaxial in this case in the boiling tube.
Consisting of From the steam conduit 4 the steam conduit 4 is guided upwards into the completely closed casing 6 of the condenser 5 as a heat-soaked body, which is present in the vessel from above the edge of the vessel 7 and heated. It is immersed in liquid 9. In this case, the steam conduit 4 opens into the casing 6 from above at a steam introduction point 28 in order not to interfere with the possibility of immersion. Into the housing 6 of the condenser 5 two dip tubes 10 and 11 from above protrude in a sealed manner through the housing wall, the end face or opening 14 of the first dip tube 10 extending into the housing interior space 17. The opening 15 of the second dip tube 11 reaches the lowest point 16.
First? ! ! It is geodesically placed slightly higher than the opening of the pipe.

The two dip tubes 10 and 11 form the legs of countercurrent siphons 12 and 13, respectively, whose further downward legs are designated siphon tube 18 and siphon beaker tube 19. The second siphon 13 is also called a siphon beaker because of its function. The two tubes 18 and 19 are guided downwards in geodesic geometry and open into the gas cavity 1420 of the tubular air collector 21, for example with a load lying vertically or obliquely;
In this case, this air collector has a constant air volume &VL. The air collector 21 valves the lower tube 22 and connects it to the return tube 23.
The condensate, replacement fluid or water is connected to the S conduit 2 of the solar collector 1 via the condensate return pipe 3.
It will be offered again. Collector 1, condenser 5 and air collector 21 form a closed system with their connecting pipes 4.12.1.3.22 and 23, which is protected against exceeding the maximum pressure. is protected by a warranty device not shown.

The siphon tube 18 or the other leg of the first siphon 12 is guided into the gas space 20 of the air collector 21 as described above, in which the opening 24 of the siphon tube 18 is guided.
is located below the opening 14 of the first dip tube of the first siphon 12 and is guided downward insofar as it forms a siphon difference ΔS1. The other leg of the siphon beaker tube 10 or the second siphon 13 is connected to the upper end 25 of the fumes trap 21, so that its opening 26 is connected to the second siphon 13.
located above the opening 15 of the dip tube 11 and with a siphon difference Δ
Form S2.

The length of the siphon beaker tube 19 must be as short as possible and the mouth 26 must be located geodesically above the opening 15. First siphon 12
is used to draw the condensate 2γ out of the casing 6, and the second siphon 13 is used to additionally balance the pressure by backflowing air during discontinuous operation. .

The functional form of the device or circuit is now described in four figures or stages with reference to FIGS. 1 to 4.

FIG. 1 shows a closed system with a collector 1 and a condenser 5. FIG. The filling container 7 has a temperature of d? The periphery of the condenser 5 is formed as a body. In the cooled state, the ladder pipe 2 and the return pipe 23 of the collector 1 are complete, and the riser pipe section and the downcomer pipe 22 of the collector 1 are partially filled with water.

The remaining circuit sections, including the condenser 5, contain air at atmospheric pressure.

Once the heat is absorbed in the collector 1, the steam flows into the condenser 5 through the riser pipe after reaching the S temperature. Originally conduit 4
Since the circulation path is closed, the air present in the condenser 5 and the condenser 5 is forced out through the condenser 5 and the siphons 12 and 13 into the downstream air collector 21 (FIG. 2). . In the condenser the vapor is condensed and in discontinuous operation the siphon 12 transfers the condensate d/ll[27 to the air collector 2
1 or to a downcomer pipe 22 and a return pipe 23.

The conveying efficiency of the first siphon 12 is that it can adapt to the rapidly changing amount of condensate in the internal space 1T of the condenser 5 due to the heat flow extracted from the pump.
Since it has to be designed for maximum volumes, it will often occur that siphon action and siphon delivery will be interrupted. After such interruption, the condensate flows into the internal space 17
regroup inside and fill this internal space from below (
(See Figure 6). However, at the same time the heat transfer area in the condenser 5 is limited to the steam side, so that insufficient condensation causes a pressure increase in the system. Accordingly, the existing air volume is reduced and the vapor seat not only compensates for the vapor compression, but also fills the space emptied by the reduced air volume.

A downwardly extending dip tube 10 of a siphon 12 in the condenser 5
In connection with the condensate 21 , which represents the separation of vapor space and air space by , this means its movement into the air collector 21 . This means that an overpressure develops in the steam line 4 and in the condenser interior 17 , which causes the condensate to rise through the siphon 12 by the length of the structural tube of the condenser 5 .

On the other hand, the first siphon 12 impairs the pressure balance due to the high water column in the cyclone tube 18 in the case of fluctuations in the heat extraction, for example in the case of cooling water delivery in the collector 1 or a reduction in efficiency. Therefore, a second siphon or three-phone beaker 13 was additionally provided to prevent fluctuations in the water level beyond the maximum marking line in the collector system. With this second siphon, a pressure equilibrium now occurs, in which case air flows back from the air collector 21 into the condenser 5, and the first siphon 12 can be transported back.

The overpressure present in the condenser 5 also serves to convey the condensate collected, for example by a siphon beaker 13, without siphoning.

However, the emptying of condensate in the air collector 21 results in a significant rate of condensation in the condenser 5. By taking advantage of the siphon effect, the condensate that initially arises can still be drawn together due to the different geodesic geometrical heights of the ports 14 and 15, thus reducing the filling and draining cycles of said working cycle. The number of repetition cycles is reduced in response to the first siphon (see Figure 4).

The ratio between the air volume VL in the collector 21 and the air container Vges in the entire circulation system must be at least as large as the ratio between the atmospheric pressure PA tm and the operating pressure PBetr. Therefore, VL should still at least
The dimensions must be such that it is possible to compensate the volumes of the two siphons 11 and 12 under a pressure ratio corresponding to the geodesic conveying height of the siphon 10.

It is important to note that a kind of bottom liquid is present in the condenser 50 casing 6 at the lowest position 16, at which the openings 14 and 15 of the dip tubes 10 and 11 open. This location 16 must be as far away from the steam conduit 28 as possible.

When the function of the circulation path was confirmed on trial, the transmission efficiency was 10
It was in the range of 100-1500 watts at a maximum steam temperature of 5°C. This corresponds to a saturation range of 1.2.3 bar.

[Brief explanation of the drawing]

1 is a schematic representation of the circuit in operation of the device according to the invention for transmitting solar energy to a liquid present in a container; FIG. 2 is a diagram showing the circuit of the device according to FIG. 1 in steady operation; FIG. FIG. 6 is a diagram showing the case at the end of the condensate rise phase in the condenser, and FIG. 4 is the case at the end of the condensate return step, provided that the water is In this drawing, circulating fluid is represented by fine parallel lines, steam is represented by circles, and air is represented by blank spaces. 1...Solar collector, 4.28...Steam conduit,
5... Condenser, 6... Casing, T... Container,
8... Container edge, 9... Liquid, 10... First immersion tube, 11... Second immersion tube, 12... First siphon,
13... Second siphon, 14... First opening, 15.
...Second opening, 17...Casing internal space, 18.
...Siphon tube, 19...Siphon beaker tube, 20
... Gas space, 21 ... Air collector, 22 ... Downcomer pipe, 24 ... Opening.

Claims (1)

[Claims] 1. a) A closed circuit in which steam is generated by direct evaporation of a heat medium in a solar collector as a heat source; b) Circulation of the heat medium in the circuit by natural convection; c) geodesically located higher than the heat source;
a solar immersion body or a heat exchanger connected in the circuit, which transfers heat to the liquid in the container, and d) a component of a conduit connecting the heat source and the heat immersion body to each other for inflow and outflow, respectively; In a device for transferring energy to a liquid present in a container, e) a thermally immersed body is inserted into the liquid (9) or into the container (7) from above;
) is formed as a steam condenser (5) that can be immersed in the vessel; A device for transmitting solar energy to a liquid present in a container, characterized in that: 2, g) the condenser (5) consists of a closed vessel (6), h)
The steam pipes (4, 28) of the solar collector (1) are connected to the internal space (17) of the casing (6) from above, i) the immersion pipe (10) is connected to the wall of the casing (6) from above; The lower end or opening (14) of this dip tube protrudes to the lowest point of the interior space (17), and j) the dip tube (10) forms the leg of a counterflow siphon (12), which siphon is connected to the container rim. k) another leg of the siphon or siphon tube (18) which is guided again downwardly on the part (8) and is guided again downwardly, preferably from above into the tubular air collector (21); l) The opening (24) of the siphon tube (18) opens into the air space (20) of the siphon tube (18), the content of which is a component of the circulating content, and the opening (24) of the siphon tube (18) m) the lower end of the air collector (21) is connected via a downcomer pipe (22) to a condensate return pipe (23) up to the solar collector (1); The device according to claim 1. 3, n) Condenser (5) from above with dip tube (10)
Alternatively, a second dip tube (11) is guided downwards into the interior space (17) of its casing (6), the end face or opening (15) of this second dip tube being geodesically geometrically aligned with the first dip tube. o) the second dip tube (11) forms one leg of the second counterflow siphon or siphon beaker (13); p) the second siphon ( q) another leg or siphon beaker tube (19), again guided downwards, of the air collector (21) opens from above into the air space (20) of the air collector (21); ) in the siphon beaker tube (19
) is located geodesically higher than the opening (24) of the siphon tube (18) of the first siphon (12) in the air collector (21). Device. 4, r) the ratio of the air volume VL in the air collector (21) to the total volume in the cooling state Vges is equal to the ratio of atmospheric pressure PAtm to operating pressure PBetr, in which case s) VL is at least Claimed to be of such a size that it is compressible by the volume of two siphon volumes under a pressure ratio corresponding to the geodesic geometric carrying height of the dip tube (10) in order to start the siphon. The device according to item 3.