SU1320612A1 - Solar heat supply system - Google Patents

Abstract

The invention relates to solar technology and makes it possible to improve the operating conditions of the system. Partially placed in the ground 1, the closed circuit 2 is filled with coolant to a level of 15, not exceeding the level of soil freezing. The pump-heater 6 is filled in the form of a cylinder with an internal polished surface and an ohmic heater covering it 12. In the expansion cavity 3 a perforated screen 14 is installed, hitting which, the liquid evenly spreads and flows by gravity into the collector 4. By reducing the sensitivity of the pump-heater 6, the power supply parameters from the photovoltaic generator 8 increase the autonomy of the heating system. The use of a pump-heater makes it possible to shorten the start-up time of the system, reduces the possibility of possible coolant leaks and the leakage of the system. 3 il. with (L 7Fi. ";

Description

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 The invention relates to solar technology, in particular to heating systems using solar heat. radiation

The purpose of the invention is to improve its operation.

Figure 1 is a diagram of a solar heating system; Fig, 2 - pump, cross section; Fig, 3 is a diagram of the installation of a perforated screen.

The solar heat supply system contains a closed circuit 2 partially placed in the ground, filled with coolant, including a successively located expansive cavity 3, a solar collector 4, heat exchangers 5 and a pump heater 6, and also connected to the heater pump 6 by conductor 7 photo galvanic generator 8. The circuit 2 also includes a valve 9, the pump-heater 6 is made in the form of a cylinder 10 with an internal polished surface 1I and an ohmic heater 12 surrounding it, surrounded by a layer of isolator and 13, In the expansion cavity 3, a perforated screen 14 is installed, and circuit 2 is partially filled with coolant to a level 15, not exceeding 1, its soil freezing level 1, and closed circuit 2 can additionally be connected through a switch 17. Terminals 18, 1 are provided for connecting an external power supply network.

The start and operation of the heat supply system is as follows.

The circuit 2 of the system through the valve 9 is filled with a coolant (for example, a mixed glass) to the specified freezing level 15, but above the pump-heater 6, then both pump heaters 6 and 16 are connected to the photovoltaic generator circuit 8 or to the external network through the terminals 18 and the heating medium is heated to a boil. Couples coolant you-. non-condensable gases (air) are cramped from the system and together with them through valve 9 are removed from the system. After the temperature difference between the boiling heat carrier and the upper part of circuit 2 becomes minimal, the valve 9 is hermetically closed and the power supply from the external network

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The voltage supplied by the photovoltaic generator 8 is turned off or lowered. As the coolant cools down, the system pressure decreases and becomes equal to the vapor pressure at the saturation temperature. When the liquid is heated under reduced pressure, the boiling is explosive, and part of the liquid column above the pump-heater 6 is broken and the fast-growing steam bubble is pushed into the upper part of circuit 2. Hitting the perforated screen 14, the liquid evenly spreads and flows by gravity into the collector 4, where, due to the radiant energy of the sun, it is heated to a higher temperature and flows into the return pipeline to the heat exchangers 5. Having removed part of the heat in the heat exchanger 5, the coolant due to the gravitational forces with the rest of the coolant, and its level above the pump-heater 6 returns to its original position. Since the polished surface 11 of the ohmic heater 12 is depleted by the centers of vaporization, the temperature difference increases between its wall and the liquid, the growth rate of the vapor bubble is deteriorated and

Consequently, the dynamic head of steam acting on the upper part of the coolant column being torn off and its speed of movement can reach 10 m / s and more. The reactive forces of the growing vapor bubble act in both directions, but since the part of the liquid column (by mass) is much smaller than the rest, a significant mass transfer through the pipeline takes place in one direction.

A decrease in the intensity of solenoid radiation reduces the frequency of liquid throws, since the parameters of the electric current coming from the photovoltaic generator 8 change. However, even after the power supply is completely disconnected, the coolant drops continue to fully equalize the pressure and temperature of the vapor and the coolant in the system .

Thus, the process of circulation of the coolant is provided due to the explosive nature of the boiling liquid under reduced pressure, which intensifies with increasing temperature:

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the difference between the fluid and the wall of the heater, and with an increase in the purity class of the internal surface of the pump-heater 6 in contact with the coolant.

Another factor that ensures the circulation efficiency is the pressure difference between the solar collector 4 zone and heat exchangers 5. The increase in pressure drop depends on the cooling intensity of heat exchangers 5 and the area of their heat transfer surfaces.

The invention makes it possible to increase the autonomy of the heating system by reducing the sensitivity of the pump-heater 6 to the power supply parameters coming from the photovoltaic generator 8. Together

so that the use of heat pump-20 bodies, in the expansion chamber of the wiring device, significantly improves the operating conditions of the heating system: the time it starts is reduced, the possibility of potential leaks is reduced

heat transfer fluid and seal system failure.

Claims (1)

Invention Formula A solar heat supply system containing a closed circuit partially placed in the ground, filled with coolant, including successively located expansion chamber, solar collector, heat exchangers and a pump, as well as a photovoltaic generator connected to the last conductors, so that that, in order to improve the operating conditions, the pump is made in the form of a cylinder with an internal polished surface and a resistively ohmic heated perforated screen, and the contour is partially About filled with coolant to a level not exceeding the level of soil freezing. ten X ff one fj V72 . 2 /// f / SL J. IL JL XL in. Jl M. 74 . 3 Editor I. Segl Nick Compiled by M.Valov Tehred V.Kadar Order 2646/42 Circulation 659 Subscription. VNIIPI USSR State Committee for inventions and discoveries 113035, Moscow, Zh-35, Raushsk nab., 4/5 Production and printing company, Uzhgorod, Projecto st., 4  / ХХ / / хх / У / // x3 Corrector T, Kolb