CN201954783U - Vacuum phase transition heat transmission type solar flat heat-collecting system - Google Patents

Abstract

The utility model discloses a vacuum phase change heat transfer type solar plate heat collection system. The system includes a flat-plate collector frame, a gas-liquid separator, a heat accumulator, a vacuum evaporator, and a condenser. The vacuum evaporator is placed inside the flat-plate collector frame and runs through the flat-plate collector frame to form two connections. end; the condenser is placed inside the heat accumulator and runs through the heat accumulator to form two connection ends; one end of the vacuum evaporator is connected to the gas-liquid separator, and the gas outlet of the gas-liquid separator is connected to one end of the condenser through the steam riser Connected, the liquid outlet of the liquid separator is connected to the other end of the vacuum evaporator through the liquid supply pipe of the evaporator, and the other end of the condenser is connected to the gas-liquid separator through the condensate return pipe. The utility model can be normally used below 0°C, realizes long-distance heat exchange, is easy to popularize and apply, can be widely used in solar heating systems, and is especially suitable for solar building integrated heating systems.

Description

Vacuum phase change heat transfer solar panel heat collection system

technical field

The utility model relates to the field of solar energy utilization, in particular to a vacuum phase change heat transfer type solar plate heat collection system.

Background technique

Solar energy is recognized as a sustainable and environmentally friendly energy source. With the continuous development of science and technology, people's use of solar energy has gradually developed from passive and semi-active to active development and utilization. How to effectively use solar energy to make up for the shortage of limited energy sources such as coal, oil, and natural gas is a hot topic in the contemporary scientific community. So far, there are two main types of solar panel collectors used by people. The first is a conventional flat plate collector, which has been commercially produced and is mainly used as a heat collecting component in a solar water heating system. It is characterized in that it is a tube-plate heat collector mainly composed of a heat-absorbing plate and upper and lower headers, a flat box-type heat collector formed by butt welding of two metal plates pressed with grooves, and the like. Although the structure of the heat absorbing plate of the collector is various, they basically use solar energy to directly heat water through the heat absorbing element. In this method, the water in the heat absorbing element is easy to freeze in winter and corrode the heat absorbing element. question. Therefore, this kind of heat collector cannot be used below 0°C, and its technical and economical efficiency is poor. The second type is the heat pipe solar panel collector, which is characterized in that a number of gravity heat pipes are used to make a heat absorbing plate, and the working fluid in the heat pipe obtains heat from the heat absorbing plate to evaporate, and then releases heat in the heat accumulator through the condenser The water is heated and condensed by itself, returns to the heat collector under the action of gravity, and then obtains energy from the heat absorbing plate, and the selected working fluid has the function of antifreezing. However, due to the large number of heat pipes, it is difficult to form separate remote connections, and it is not suitable for installation on the wall of buildings. In addition, this kind of heat collector is too expensive to manufacture, has low thermal efficiency, and the manufacturing process is complicated, so it is difficult to popularize and apply.

Utility model content

The technical problem to be solved by the utility model is to provide a vacuum phase change heat transfer type solar panel heat collection system, which cannot be used below 0°C for conventional heat collectors, or the cost of heat pipe type solar panel heat collectors is high, Due to the problems of not being able to separate the installation and being difficult to popularize, an innovative device is proposed, that is, a solar panel heat collection system with separate installation of the heat collector and the heat accumulator, and the use of vacuum phase change heat transfer of the working fluid. This system has high efficiency and The cost is low, and it can still be used normally below 0°C. The collectors of this system can be installed not only on the roof of the building, but also on its wall.

The technical solution adopted by the utility model to solve the above problems is: a vacuum phase change heat transfer type solar panel heat collection system, including a panel collector frame, a gas-liquid separator, a heat accumulator, a vacuum evaporator, a condenser, a vacuum The evaporator is placed inside the frame of the flat-plate heat collector and runs through the frame of the flat-plate heat collector to form two connection ends; the condenser is placed inside the heat accumulator and passes through the heat accumulator to form two connection ends; one end of the vacuum evaporator It is connected to the gas-liquid separator, the gas outlet of the gas-liquid separator is connected to one end of the condenser through the vapor rising pipe, the liquid outlet of the liquid separator is connected to the other end of the vacuum evaporator through the evaporator liquid supply pipe, and the condenser The other end is connected to the gas-liquid separator through the condensate return pipe.

Specifically, the vacuum evaporator is a serpentine coil and a heat absorbing element is connected to the serpentine coil. The condenser can also be any other type of coil. The vacuum evaporator is installed in the frame of the flat-plate heat collector, and the heat-absorbing element is connected to the serpentine tube. The area of the heat-absorbing element is equal to the light-receiving area of the heat collector. Evaporation takes heat away.

The ratio of the heat exchange area of the vacuum evaporator to the area of the heat absorbing element is 0.30-0.80.

The condenser is a serpentine, spiral or oblong coil, and the accumulator is provided with a cold water inlet pipe and a hot water outlet pipe. The condenser can also be any other form of coil, installed in the heat accumulator, the working fluid condenses in the condenser and releases heat to heat the material in the heat accumulator.

The ratio of the heat exchange area of the condenser to the area of the heat absorbing element is 0.30˜1.0.

A steam trap is connected to the bottom of the gas-liquid separator, and the condensate return pipe of the condenser is connected to the side of the bottom of the gas-liquid separator.

The sequential connection of the vacuum evaporator, gas-liquid separator, steam rising pipe, condenser, condensate return pipe, and evaporator liquid supply pipe constitutes a working medium circulation loop, and the working medium filling volume in the working medium circulation loop is vacuum 5-50% of the volume of the evaporator.

The vacuum degree in the vacuum evaporator is 4-98kPa.

A kind of working fluid specially used in the above-mentioned vacuum phase change heat transfer type solar panel heat collection system, the working fluid is water, ammonia, ether, furan, acetone, methyl ethyl ketone, chloroform, methanol, ethanol, n-propanol, isopropanol, One or more of propanol, pentane, isopentane, hexane, and cyclohexane, with a boiling point of 30°C to 90°C. The above-mentioned working fluid is a multi-component composite working fluid, which is a liquid phase substance or several liquid phase substances that are easy to change phases, and its boiling point is adjustable within the range of 30°C to 90°C.

The working principle of the utility model is: the vacuum evaporator of the serpentine coil is used to replace the heat collecting element of the traditional flat plate heat collector, and its function is similar to the evaporator of an air conditioner or a refrigerator, and the working medium in the tube is unidirectional under the action of the pressure difference It flows and absorbs heat and evaporates to take away the latent heat. When it reaches the outlet of the evaporator, it is in a vapor state, and the heat transfer efficiency is high; while the tube of the traditional flat plate collector is water, which absorbs sensible heat through the collector, and uses cold and hot water The density difference is naturally circulated, and the heat transfer efficiency is low. The evaporator forms a closed working medium circulation loop through the steam rising pipe, the condenser in the detachable heat accumulator, the condensate return pipe and the evaporator liquid supply pipe, and the circuit is filled with heat transfer working fluid. In the case of sunlight during the day, the working fluid is heated and evaporated in the vacuum evaporator to become saturated steam or wet steam, and then enters the condenser in the heat accumulator through the gas-liquid separator through the steam riser. In the condenser, the steam releases heat to the water outside the condenser tube, is condensed and cooled, and at the same time, the material in the heat accumulator is heated. The condensed coolant returns to the bottom of the gas-liquid separator through the condensate return pipe under gravity, and then returns to the vacuum evaporator through the evaporator liquid supply pipe to complete a working cycle. In the cycle process, the working medium absorbs the energy supplied by the sun to the heat-absorbing element in the vacuum evaporator, is heated and evaporated, and releases the latent heat of vaporization and sensible heat in the condenser to be condensed and cooled into a supercooled liquid. This phase change cycle This is repeated to heat the contents of the regenerator to the desired temperature. Heat transfer is better if the material in the accumulator can flow. The gas-liquid separator in the working medium circulation loop can play the role of gas-liquid separation to ensure the normal operation of the cycle. If wet vapor comes out of the vacuum evaporator, the separated saturated liquid will drop to the bottom of the gas-liquid separator; if wet vapor comes out of the condenser, the separated vapor will enter the condenser through the vapor riser. If the accumulator contains water and is insulated accordingly, the system can be a split antifreeze solar water heater with a hot water storage tank; Thermal split type freeze-proof solar air heater.

In summary, the beneficial effects of the utility model are:

(1) The utility model uses a closed working medium natural circulation loop to connect the far apart flat plate heat collector frame and heat accumulator, and fills the low boiling point multi-component composite working medium in the loop. The phase change cycle of the heat accumulator heats the substance to be heated (such as water) in the heat accumulator. The system has a simple structure, can be used normally below 0°C, realizes long-distance heat exchange, is easy to popularize and apply, and can be widely used in solar heating systems, especially suitable for building-integrated solar heating systems.

(2) The utility model adopts multi-component composite working medium, which has no corrosive effect, and the boiling point can be adjusted in a wide range. Even if the temperature in the north is low, no solidification and other phenomena will occur, and the normal operation of the system can still be guaranteed in winter. The scope of application of the system is increased.

Description of drawings

Fig. 1 is a schematic flow chart of the utility model vacuum phase change heat transfer type solar panel heat collecting system.

The names of the parts corresponding to the marks in the figure: 1—Flat collector frame; 2—Vacuum evaporator; 3—Evaporator liquid supply pipe; 4—Gas-liquid separator; 5—Condensate return pipe; Tube; 7—condenser; 8—regenerator; 9—cold water inlet pipe; 10—hot water outlet pipe.

Detailed ways

The utility model will be further described in detail below in conjunction with the embodiments and accompanying drawings, but the implementation of the utility model is not limited thereto.

Example 1:

Referring to Fig. 1, the vacuum phase change heat transfer type solar panel heat collection system of this embodiment includes a panel collector frame 1, a gas-liquid separator 4, a heat accumulator 8, a vacuum evaporator 2, and a condenser 7, The vacuum evaporator 2 and the condenser 7 are respectively placed inside the flat plate collector frame 1 and the heat accumulator 8 and run through the flat plate heat collector frame 1 and the heat accumulator 8 to form two connecting ends. The vacuum evaporator 2 One end is connected to the gas-liquid separator 4, the gas outlet of the gas-liquid separator 4 is connected to one end of the condenser 7 through the steam rising pipe 6, and the liquid outlet of the liquid separator 4 is connected to the vacuum evaporator 2 through the liquid supply pipe 3 of the evaporator The other end is connected, and the other end of the condenser 7 is connected with the gas-liquid separator 4 through the condensate return pipe 5 .

Wherein, the vacuum evaporator 2 is a serpentine coil installed in the flat plate heat collector frame 1, and a heat absorbing element is connected to the serpentine pipe, and the area of the heat absorbing element is equal to the light-receiving area of the heat collector. The working fluid absorbs the heat from the heat-absorbing element in the serpentine tube, and then evaporates to take away the heat. The ratio of the heat exchange area of the vacuum evaporator 2 to the area of the heat absorbing element is 0.30-0.80.

The condenser 7 is any form of coil, such as serpentine, spiral, oblong coil, etc., installed in the heat accumulator 8, and the ratio of the heat exchange area to the area of the heat absorbing element is 0.30-1.0. The working fluid condenses in the condenser 7 and releases heat to heat the material in the heat accumulator 8 .

The gas-liquid separator 4 is a closed container of any shape, the bottom of which is connected with a steam trap (or not connected with a valve), and is connected with the liquid supply pipe 3 of the evaporator, and its top is connected with the vapor rising pipe 6, and the vacuum evaporator 2 The steam pipe can be connected to the upper side of the gas-liquid separator 4 at any angle, and the condensate return pipe 5 of the condenser 7 is connected to the side of the bottom of the gas-liquid separator 4 .

The sequential connection of the above-mentioned vacuum evaporator 2, gas-liquid separator 4, vapor riser 6, condenser 7, condensate return pipe 5, and evaporator liquid supply pipe 3 (refer to the connection method in Figure 1) constitutes a working medium circulation loop. Vacuum evaporator 2, connecting pipe fittings, and condenser 7 are made of copper or stainless steel, and gas-liquid separator 4 is made of stainless steel. After being integrated by welding or threaded connection, pressure leak detection is performed. Then loosen the connecting nuts, put the vacuum evaporator 2 and the condenser 7 into the flat plate heat collector frame 1 and the heat accumulator 8 respectively, and then connect the pipelines. Finally, evacuate the system and fill the working fluid, the filling volume of the working fluid is 5% to 50% of the volume of the vacuum evaporator.

Example 2:

A working fluid specially used in the vacuum phase change heat transfer type solar panel heat collection system described in Example 1, the working fluid is a multi-component composite working fluid.

The multi-component composite working medium is one or several kinds of liquid-gas phase change substances.

The liquid-gas phase change substance is one of water, ammonia, ether, furan, acetone, methyl ethyl ketone, chloroform, methanol, ethanol, n-propanol, isopropanol, pentane, isopentane, hexane, cyclohexane species or more than one species.

Example 1, water is used as the working fluid, the vacuum degree is 85.59kPa, and the evaporation temperature of the working fluid after the system is installed is 55°C.

Example 2, using ethanol as the working fluid, the vacuum degree is 63.09kPa, and the evaporation temperature of the working fluid after the system is installed is 55°C.

Example 3, a mixture of acetone and methanol is used as the working fluid, the molar ratio of acetone and methanol is 0.22:0.78, the absolute pressure is 1 atm, and the evaporation temperature of the working fluid after the system is installed is 55.28°C.

Example 4, use a mixture of acetone and chloroform as the working fluid, the molar ratio of acetone and chloroform is 0.35:0.65, the vacuum degree is 32.32kPa, and the evaporation temperature of the working fluid after the system is installed is 55°C.

The above are only preferred implementation cases of the present invention, and are not intended to limit the present invention in any form. Any simple modifications or equivalent changes made to the above implementation cases in essence by the technology of the present invention all fall into the scope of the present invention. within the scope of protection.

As mentioned above, the utility model can be better realized.

Claims (8)

1. phase transition of vacuum heat transfer type plate solar collecting system, it is characterized in that, comprise flat plate collector framework (1), gas-liquid separator (4), storage heater (8), cold boiler (2), condenser (7), cold boiler (2) places flat plate collector framework (1) inside and runs through flat plate collector framework (1) and forms two links; Condenser (7) places storage heater (8) inside and runs through storage heater (8) and forms two links; Described cold boiler (2) one ends and gas-liquid separator (4) are connected, gas-liquid separator (4) gas vent is logical with a termination of condenser (7) by vapor uptake (6), liquid/gas separator (4) liquid outlet is connected by the evaporimeter feed pipe (3) and the other end of cold boiler (2), and the other end of condenser (7) is connected by condensate liquid return duct (5) and gas-liquid separator (4).

2. phase transition of vacuum heat transfer type plate solar collecting system according to claim 1 is characterized in that described cold boiler (2) is to be connected with heat absorbing element on serpentine coil and the serpentine coil.

3. phase transition of vacuum heat transfer type plate solar collecting system according to claim 1 and 2 is characterized in that the heat exchange area of described cold boiler (2) is 0.30～0.80 with the ratio of heat absorbing element area.

4. phase transition of vacuum heat transfer type plate solar collecting system according to claim 1 and 2, it is characterized in that, described condenser (7) is to be snakelike, spirality or Long Circle coil pipe, and storage heater (8) is provided with cold water inlet (9) and hot water outlet pipe (10).

5. phase transition of vacuum heat transfer type plate solar collecting system according to claim 1 and 2 is characterized in that the heat exchange area of described condenser (7) is 0.30～1.0 with the ratio of heat absorbing element area.

6. phase transition of vacuum heat transfer type plate solar collecting system according to claim 1 and 2, it is characterized in that, described gas-liquid separator (4) bottom is connected with drain valve, and the condensate liquid return duct (5) of condenser (7) links to each other with the side of gas-liquid separator (4) bottom.

7. phase transition of vacuum heat transfer type plate solar collecting system according to claim 1 and 2, it is characterized in that, described cold boiler (2), gas-liquid separator (4), vapor uptake (6), condenser (7), condensate liquid return duct (5), being linked in sequence of evaporimeter feed pipe (3) constitute the working medium closed circuit, and the working medium filling weight in the working medium closed circuit is 5～50% of a cold boiler volume.

8. phase transition of vacuum heat transfer type plate solar collecting system according to claim 7 is characterized in that, the vacuum in the described cold boiler is 4～98kPa.

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