A heating type prefabricated pile based on heat pipe effect and construction method

Abstract

The present invention discloses a heating type prefabricated pile based on the heat pipe effect and a construction method, comprising a pile body and a heat pipe, wherein the outer side of the heat pipe is wrapped with a first heat conducting sheet, a temperature sensor is preset in the first heat conducting sheet, a plurality of second heat conducting sheets are spaced apart on the top of the heat pipe, a resistor is installed on the second heat conducting sheet, a valve is also installed on the top of the heat pipe, a blower is covered on the outer side of the second heat conducting sheet and the valve, and the blower, the resistor and the temperature sensor are connected to a control end; the pile body is arranged on the outer side of the heat pipe. The present invention mainly utilizes the heat pipe effect to utilize geothermal energy. First, a certain amount of water is injected into the heat pipe, and then a vacuum pump is used to reduce the air pressure in the heat pipe. When the air pressure is reduced to a certain value, the water will begin to boil under the action of geothermal energy, and the water vapor will move upward to the top of the heat pipe. After the copper sheet absorbs the water vapor in the heat pipe, the heat is taken out by the blower. The water vapor loses heat and condenses into water, thereby realizing the utilization of geothermal energy in a reciprocating cycle.

Description

Technical Field

[0001] The present invention relates to a prefabricated pile and a construction method, and in particular to a heating type prefabricated pile based on a heat pipe effect and a construction method. Background Art

[0002] Energy piles, a new environmentally friendly method for utilizing geothermal energy, have been proven feasible by numerous researchers. However, traditional energy piles use water as the medium for transferring heat to the ground. This water must be injected into pipes, heated, and then circulated to the surface using a pump to utilize the geothermal energy. This process consumes a lot of energy, and liquid water has low thermal conductivity. Therefore, a new type of energy pile with high thermal conductivity and no need for a water pump is needed, enabling efficient utilization of geothermal energy without additional energy consumption. Summary of the Invention

[0003] Purpose of the invention: The purpose of the present invention is to provide a heating type prefabricated pile and construction method based on the heat pipe effect, which makes full use of the characteristic of the lowering of the boiling point of water under low pressure, so that water is converted into water vapor under the action of geothermal energy. The thermal energy of the water vapor will be conducted to the heat-conducting copper sheet, and then the heat energy will be transported to the outside world by a blower; the liquid and gaseous states of water are used to conduct geothermal heat. This process can realize automatic circulation without the need for additional mechanical work, and the heat conversion efficiency between liquid and gaseous states will be much higher than the traditional liquid water circulation method.

[0004] Technical solution: The present invention includes a pile body and a heat pipe, the outside of the heat pipe is wrapped with a first heat-conducting plate, a temperature sensor is preset in the first heat-conducting plate, a plurality of second heat-conducting plates are arranged at intervals on the top of the heat pipe, a resistor is installed on the second heat-conducting plate, a valve is also installed on the top of the heat pipe, a blower is covered on the outside of the second heat-conducting plate and the valve, the blower, resistor and temperature sensor are connected to the control end; the pile body is arranged on the outside of the heat pipe.

[0005] The first heat-conducting sheet is a heat-conducting silicone sheet, and a temperature sensor is preset in the heat-conducting silicone sheet, and the temperature sensor is below the water level line.

[0006] The second heat conducting sheet is a heat conducting copper sheet, and the resistor is a thermistor.

[0007] The valve is used to inject liquid into the heat pipe, the valve is connected to a vacuum pump, and the vacuum pump is connected to a control end.

[0008] A pile tip is provided at the bottom of the pile body, and the pile tip is in a cone shape.

[0009] The pile body and the pile tip are made of concrete, and the air inside the concrete is exhausted by a vacuum method, so that the pores in the concrete pile body are reduced, thereby improving the thermal conductivity.

[0010] The heat pipe is made of metal with good thermal conductivity.

[0011] A construction method for heating prefabricated piles based on heat pipe effect, comprising the following steps:

[0012] (1) Molded heat pipe;

[0013] (2) Wrap the heat pipe with a thermally conductive silicone sheet, place a temperature sensor in the silicone sheet and reserve a circuit, and then place it in the pile mold;

[0014] (3) After the concrete is mixed and the air is removed by vacuum method, it is placed in a pile mold. After the curing is completed, the mold is removed to form a concrete pile with a heat pipe;

[0015] (4) After the pile is driven into the soil, several thermal conductive copper sheets are placed on top of the heat pipe, and a thermistor is placed on the thermal conductive copper sheets;

[0016] (5) Place a valve on the upper bottom surface, inject salt water into the interior through the valve on the top of the heat pipe, and then connect the valve to the vacuum pump;

[0017] (6) Place a blower outside the heat-conducting copper sheet and valve;

[0018] (7) Connect the blower, vacuum pump, thermistor and temperature sensor to the control terminal;

[0019] (8) The soil temperature is obtained through the temperature sensor, and then the boiling pressure of water at the current soil temperature is obtained through the Magnus empirical formula;

[0020] (9) Turn on the vacuum pump through the control end to reduce the air pressure in the heat pipe to the target pressure;

[0021] (10) When the water begins to boil, the water vapor rises to the top of the heat pipe, and its heat energy is absorbed by the heat-conducting copper sheet. After condensation, the water vapor is converted into liquid water and then falls to the bottom of the heat pipe, repeating the cycle to realize the utilization of geothermal energy.

[0022] (11) When the heat-conducting copper sheet absorbs heat energy, the control end detects that the resistance of the thermistor decreases, turns on the blower, and transmits the heat energy to the outside.

[0023] Beneficial effects:

[0024] (1) The present invention mainly utilizes the characteristic of lowering the boiling point of water under low pressure to convert water into water vapor under the action of geothermal energy. The heat energy of the water vapor is transferred to the heat-conducting copper sheet, and then the heat energy is transported to the outside by a blower. The liquid and gaseous states of water are used to conduct geothermal heat. This process can realize automatic circulation without the need for additional mechanical work, and the heat conversion efficiency between liquid and gaseous states will be much higher than the traditional liquid water circulation method.

[0025] (2) The present invention utilizes copper sheets for heat conduction, which is highly efficient and enables rapid utilization of geothermal energy;

[0026] (3) The present invention utilizes the characteristics of thermistors to turn on the blower only when the temperature of the copper sheet rises. This ensures that the blower is suspended when the local thermal effect is not obvious, thereby reducing energy consumption and achieving the purpose of energy conservation.

[0027] (4) The present invention adds a soft thermally conductive silicone sheet, which ensures heat conduction while also preventing the thermal expansion and contraction of the heat pipe from affecting the concrete components;

[0028] (5) The present invention uses salt water as a medium for heat exchange. Salt ions can serve as condensation nuclei to quickly condense water vapor, thereby accelerating the rate of geothermal exchange. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 It is a schematic diagram of the overall structure of the present invention;

[0030] Figure 2 A top view of the present invention;

[0031] Figure 3 It is a cross-sectional view of the present invention. DETAILED DESCRIPTION

[0032] The present invention will be further described below with reference to the accompanying drawings.

[0033] like Figures 1 to 3 As shown, the present invention includes a pile body 7 and a heat pipe 9. The heat pipe 9 is made of a metal with good thermal conductivity, with a length of 5-10 meters, a diameter of 0.5-2 meters, and a thickness of 10-80 mm. The thickness is mainly set according to the length and diameter of the heat pipe to avoid large deformation caused by thermal expansion and contraction. The upper and lower bottom surfaces of the heat pipe 9 are respectively welded with metal sheets to ensure the airtightness of the heat pipe 9. The outside of the heat pipe 9 is wrapped with a thermally conductive silicone sheet 8, which has a thickness of 3-10 mm and a length the same as the length of the heat pipe 9. A temperature sensor 10 is preset in the thermally conductive silicone sheet 8. Its position should be close to the bottom of the heat pipe 9 and needs to be below the water level to ensure that the temperature of the water is measured. The circuit of the temperature sensor 10 is reserved in the thermally conductive silicone sheet 8.

[0034] The pile body 7 is provided with a pile tip 11 at the bottom. The pile body 7 and pile tip 11 are made of concrete. Depending on the specific project, the concrete mix consists of 10-20 parts of cement with a grade of C30 or higher, 4-8 parts of natural river sand, 2-4 parts of crushed stone, 1-3 parts of volcanic ash, 2-3 parts of high-strength ceramsite, and 5-10 parts of water. After thorough mixing, the concrete is vacuum-extracted to ensure excellent thermal conductivity.

[0035] Heat pipe 9 is placed in a prefabricated pile mold, concrete is poured into the mold, and after being cured by autoclaving for 20-28 days, the mold is removed to form a concrete pile with heat pipe 9. After the pile is sent into the foundation, a plurality of heat-conducting copper sheets 5 are welded at intervals on the top of the heat pipe 9. The thickness of the heat-conducting copper sheets 5 is 0.1-2mm, and the length and height are determined according to the size of the heat pipe 9, and are placed at intervals of 1-3cm. The heat-conducting copper sheets 5 are equipped with a thermistor 4 and a reserved circuit. The top of the heat pipe 9 is also provided with a hole for accommodating a valve 6. Through the valve 6, salt water is injected into the heat pipe 9. The salt content is 1%-5%. The salt ions therein can serve as condensation nuclei to rapidly condense water vapor. The water injection rate is determined according to the size of the heat pipe 9. Then connect the valve 6 to the vacuum pump 2, and finally install the blower 3 on the top of the heat pipe 9. The blower 3 is covered on the outside of the thermal copper sheet 5 and the valve 6. The lines of the blower 3, vacuum pump 2, thermistor 4 and temperature sensor 10 are all connected to the control end 1. The control end 1 is composed of a Windows system, a vacuum pump operating system and a thermistor detection system.

[0036] A construction method for heating prefabricated piles based on heat pipe effect, comprising the following steps:

[0037] (1) Using high temperature to melt the metal, pouring the liquid metal into a cylindrical mold, and taking it out after cooling to make a metal cylinder;

[0038] (2) Two metal discs are made and welded together as the upper and lower bottom surfaces of the metal cylinder to form a heat pipe 9;

[0039] (3) Wrap the heat pipe with a thermally conductive silicone sheet 8, place a temperature sensor 10 in the silicone sheet and reserve a circuit, and then place it in the pile mold;

[0040] (4) After the concrete is mixed and the air is removed by vacuum method, it is placed in a pile mold. After the curing is completed, the mold is removed to form a concrete pile with a heat pipe;

[0041] (5) After the pile is driven into the soil by static pressure, several thermal conductive copper sheets 5 are welded on the top of the heat pipe, and a thermistor 4 is placed on the thermal conductive copper sheet. A hole is opened on the upper bottom surface and a valve 6 is placed;

[0042] (6) Inject saline water into the heat pipe through the valve at the top of the heat pipe, and then connect valve 6 to the vacuum pump 2;

[0043] (7) Place the blower 3 outside the heat-conducting copper sheet 5 and the valve 6;

[0044] (8) Connect the blower 3, vacuum pump 2, thermistor 4 and temperature sensor 10 to the control terminal 1;

[0045] (9) The soil temperature is obtained by the temperature sensor 10, and then the Magnus empirical formula is used to calculate the soil temperature. Get the boiling pressure of water at the current soil temperature, where t is the temperature and E 水 is the saturated water vapor pressure when the water surface temperature is t, E0 is the saturated water vapor pressure when the water surface temperature is 0℃;

[0046] (10) Turn on the vacuum pump 2 through the control terminal 1 to reduce the air pressure in the heat pipe 9 to the target pressure;

[0047] (11) When the water begins to boil, the water vapor rises to the top of the heat pipe, and its heat energy is absorbed by the heat-conducting copper sheet 5. After condensation, the water vapor is converted into liquid water and then falls to the bottom of the heat pipe, and the cycle repeats to realize the utilization of geothermal energy.

[0048] (12) When the heat-conducting copper sheet 5 absorbs heat energy, the control terminal 1 detects that the resistance of the thermistor 4 decreases, thereby turning on the blower 3 to transport the heat energy to the outside.

[0049] The present invention mainly utilizes geothermal energy by utilizing the heat pipe effect. First, a certain amount of water is injected into the heat pipe, and then a vacuum pump is used to reduce the air pressure in the heat pipe. When the air pressure is reduced to a certain value, the water will begin to boil under the action of geothermal energy, and the water vapor will move upward to the top of the heat pipe. After the copper sheet absorbs the water vapor in the heat pipe, the heat is taken out by the blower. The water vapor loses heat and condenses into water, thus realizing the utilization of geothermal energy through a cycle. It is mainly suitable for low-temperature areas where the underground temperature is higher than the ground temperature.

Claims

1. A construction method of a heating type prefabricated pile based on heat pipe effect, characterized in that: The invention comprises a heating type prefabricated pile based on the heat pipe effect, the prefabricated pile comprising a pile body and a heat pipe, the outer side of the heat pipe is wrapped with a first heat conducting sheet, a temperature sensor is preset in the first heat conducting sheet, a plurality of second heat conducting sheets are arranged at intervals on the top of the heat pipe, a resistor is installed on the second heat conducting sheet, a valve is also installed on the top of the heat pipe, the valve is connected to a vacuum pump, the vacuum pump is connected to a control end, a blower is covered on the outer side of the second heat conducting sheet and the valve, the blower, the resistor and the temperature sensor are connected to the control end; the first heat conducting sheet is a heat conducting silicone sheet; the second heat conducting sheet is a heat conducting copper sheet, and the resistor is a thermistor; the pile body is arranged on the outer side of the heat pipe, and the construction method comprises the following steps: (1) Molded heat pipe; (2) Wrap the heat pipe with a thermal conductive silicone sheet, place a temperature sensor in the silicone sheet and reserve a circuit, and then place it in the pile mold; (3) After the concrete is mixed and the air is removed by vacuum method, it is placed in the pile mold. After the curing is completed, the mold is removed to form a concrete pile with a heat pipe; (4) After the pile is driven into the soil, several thermal conductive copper sheets are placed on the top of the heat pipe and thermistors are placed on the thermal conductive copper sheets; (5) Place a valve on the upper bottom surface, inject salt water into the interior through the valve on the top of the heat pipe, and then connect the valve to the vacuum pump; (6) Place a blower outside the heat-conducting copper sheet and valve; (7) Connect the blower, vacuum pump, thermistor and temperature sensor to the control terminal; (8) Obtain the soil temperature through the temperature sensor, and then use the Magnus empirical formula to obtain the boiling pressure of water at the current soil temperature; (9) Turn on the vacuum pump through the control end to reduce the air pressure in the heat pipe to the target pressure; (10) When the water begins to boil, the water vapor rises to the top of the heat pipe, and its heat energy is absorbed by the heat-conducting copper sheet. After condensation, the water vapor is converted into liquid water and then falls to the bottom of the heat pipe, repeating the cycle to realize the utilization of geothermal energy. (11) When the heat-conducting copper sheet absorbs heat energy, the control end detects that the resistance of the thermistor decreases, turns on the blower, and transmits the heat energy to the outside.

2. The construction method of a heating type prefabricated pile based on heat pipe effect according to claim 1, characterized in that: A temperature sensor is preset in the thermally conductive silicone sheet, and the temperature sensor is below the water level line.

3. The construction method of a heating type prefabricated pile based on heat pipe effect according to claim 1, characterized in that: A pile tip is provided at the bottom of the pile body.

4. The construction method of a heating type prefabricated pile based on heat pipe effect according to claim 3 is characterized in that: The pile body and the pile tip are made of concrete, and the air inside the concrete is exhausted by a vacuum method.

5. The construction method of a heating type prefabricated pile based on heat pipe effect according to claim 1, characterized in that: The heat pipe is made of metal with good thermal conductivity.

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