Cold region tunnel portal air curtain heat preservation system utilizing geothermal energy

Abstract

The invention provides a cold region tunnel portal air curtain heat preservation system utilizing geothermal energy, comprising: a geothermal energy heat extraction device, the geothermal energy heat extraction device comprises a heat extraction drill hole arranged in the middle section surrounding rock of a tunnel and a heat extraction pipe arranged in the heat extraction drill hole, and the heat extraction pipe is internally provided with a heat extraction medium; the arc-shaped air curtain unit is provided with air curtain machines which are uniformly arranged in the circumferential direction of the inner side of the tunnel portal lining; the ground source heat pump is used for providing heat energy for the air heating cavity by taking geothermal energy as a heat source; clean and green geothermal energy and the air curtain technology are combined to achieve long-term prevention of cold damage to the tunnel portal in the cold region, the geothermal energy is transferred to the tunnel portal, a hot air curtain wall is formed at the portal through the air curtain technology, cold energy outside the tunnel is prevented from being transferred into the tunnel, and safety and no influence on driving installation are achieved.

Description

Technical Field

[0001] The present invention belongs to the technical field of cold region tunnel insulation, and in particular relates to a cold region tunnel portal air curtain insulation system utilizing geothermal energy. Background Art

[0002] With rapid economic and social development, my country has planned and constructed a large number of tunnel projects in severely cold regions. The impact of cold environments on tunnel construction and subsequent operations is becoming increasingly prominent, particularly with regard to frost damage at tunnel portals. When cold air enters the tunnel, it not only shrinks and cracks the lining, increasing construction difficulties, but also causes frost heave and deformation in the surrounding rock, threatening the safety of the tunnel structure. Therefore, effectively improving the thermal insulation performance of tunnel portals in cold regions and reducing the impact of cold air on the tunnel environment have become technical challenges in tunnel construction and maintenance in cold regions.

[0003] Existing insulation measures for tunnels in cold regions mostly rely on local electric heating equipment, such as the cold-region tunnel antifreeze insulation system and antifreeze insulation construction method disclosed in the Chinese invention patent document with authorization announcement number CN104775833B. These methods have high energy consumption and are expensive, making them unsuitable for operation throughout the full life cycle of cold-region tunnel projects.

[0004] Geothermal energy is a renewable, green energy source that, through scientific design, can provide a continuous source of energy for tunnel entrances. Meanwhile, air curtain technology, a common air insulation method, has been widely used in the insulation of buildings, doors, and windows, but its application in tunnel entrances in cold regions has been less studied. Summary of the Invention

[0005] In view of the deficiencies in the prior art, the present invention provides a cold region tunnel entrance air curtain insulation system that utilizes geothermal energy and can solve the insulation technical problems of cold region tunnel entrances in a long period, with low energy consumption and high efficiency.

[0006] The technical solution of the present invention is: a cold-region tunnel portal air curtain insulation system utilizing geothermal energy, comprising: a geothermal heat extraction device, the geothermal heat extraction device comprising a heat extraction borehole opened in the surrounding rock of the middle section of the tunnel and a heat extraction pipe arranged inside the heat extraction borehole, the interior of the heat extraction pipe containing a heat extraction medium; a curved air curtain unit, the curved air curtain unit comprising air curtain machines uniformly arranged circumferentially along the inner side of the tunnel portal lining, the air curtain machine having an air curtain machine housing fixedly connected to the inner side of the tunnel portal lining, an air heating chamber provided inside the air curtain machine housing, a fan provided below the air heating chamber, the fan driving the cold air at the tunnel portal to pass through the air heating chamber for heating and then guide it into the tunnel, forming a hot air curtain wall on the cross section of the tunnel; and a ground source heat pump, the ground source heat pump being connected to the geothermal heat extraction device and the curved air curtain unit respectively, the ground source heat pump using geothermal energy as a heat source to provide heat energy to the air heating chamber.

[0007] Furthermore, fins and curved water pipes are provided inside the air heating chamber, and the fins are thermally connected to the curved water pipes; the air curtain housing is provided with a heat exchange medium inlet and a heat exchange medium outlet respectively connected to the two ends of the curved water pipes; the heat exchange medium inlet and the heat exchange medium outlet are connected to the ground source heat pump through water pipes.

[0008] Furthermore, an electric heating component is provided inside the air heating cavity, and the electric heating component is used to heat the air passing through the air heating cavity.

[0009] Furthermore, the cold region tunnel entrance air curtain insulation system utilizing geothermal energy also includes a controller, to which a first temperature sensor, a second temperature sensor, and a third temperature sensor are connected. The first temperature sensor is used to detect the air temperature inside the tunnel, the second temperature sensor is used to detect the air temperature outside the tunnel, and the third temperature sensor is used to detect the air temperature inside the air heating chamber. The controller is used to control the speed of the fan.

[0010] Furthermore, the ground source heat pump has a water pump unit and a ground source heat pump control panel, and the ground source heat pump is connected to the heat extraction pipe.

[0011] Furthermore, the water pump unit is connected to the heat extraction pipe through a heat transfer pipeline.

[0012] Furthermore, the outer side of the heat transfer pipeline is wrapped with thermal insulation cotton with a thickness of at least 10 mm.

[0013] Furthermore, insulation side trenches are provided on both sides of the interior of the tunnel, and the heat transfer pipeline is laid inside the insulation side trenches.

[0014] Furthermore, the heat extraction pipe is a U-shaped heat extraction pipe. After the heat extraction pipe is installed in place inside the heat extraction borehole, the inside of the heat extraction borehole is backfilled with a self-leveling material with high thermal conductivity.

[0015] Furthermore, a guide fan blade is provided below the fan, and the fan drives the cold air at the tunnel entrance to pass through the air heating chamber for heating and then guide the cold air into the tunnel by the guide fan blade.

[0016] Beneficial effects of the present invention:

[0017] (1) The present invention combines clean and green geothermal energy with wind curtain technology to achieve long-term prevention of frost damage at tunnel entrances in cold regions. The geothermal energy is transferred to the tunnel entrance, and wind curtain technology is used to form a hot air curtain wall at the tunnel entrance, blocking the cold energy outside the tunnel from being transferred into the tunnel, which is safe and does not affect driving installation.

[0018] (2) The system has low energy consumption and can achieve the purpose of heat preservation in tunnels during winter operation throughout the life cycle of cold-region tunnel projects;

[0019] (3) The air curtain machine is installed on the inner wall of the tunnel lining. For existing tunnels, the heat extraction drilling holes can be set in the tunnel cross passage, which can realize the long-term anti-freeze and heat preservation transformation of existing cold-region tunnels. For newly built tunnels, the insulation system of the present invention can be installed after the first lining of the tunnel is completed, and it can be used for a long time during the construction and operation periods.

[0020] (4) The curved air curtain unit utilizes geothermal energy to increase the temperature of the air curtain wall formed by the curved air curtain unit, thereby improving the efficiency of the air curtain technology in blocking the cold air outside the cave. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 This is a schematic structural diagram of the cold region tunnel entrance air curtain insulation system utilizing geothermal energy in the present invention.

[0022] Figure 2 This is a schematic diagram of the structure of the heat pipe buried in the surrounding rock in the middle section of the tunnel in the present invention.

[0023] Figure 3 This is a schematic diagram of the principle of the cold region tunnel entrance air curtain insulation system using geothermal energy in the present invention.

[0024] Figure 4 Schematic diagram of the internal structure of the air heating chamber in the present invention. DETAILED DESCRIPTION

[0025] Various exemplary embodiments of the present invention will now be described in detail with reference to the accompanying drawings. The description of the exemplary embodiments is merely illustrative and is in no way intended to limit the present invention, its application, or use. The present invention can be implemented in many different forms and is not limited to the embodiments described herein. These embodiments are provided to make the present invention thorough and complete and to fully convey the scope of the present invention to those skilled in the art. It should be noted that unless otherwise specifically stated, the relative arrangement of components and steps, the composition of materials, numerical expressions, and numerical values set forth in these embodiments should be interpreted as being merely exemplary and not as limiting.

[0026] The terms "first," "second," and similar terms used in this disclosure do not indicate any order, quantity, or importance, but are simply used to distinguish different parts. Terms such as "include" or "comprising" mean that the elements preceding the term include the elements listed after the term, and do not exclude the possibility of also including other elements. Terms such as "upper," "lower," "left," and "right" are used only to indicate relative positional relationships. When the absolute position of the object being described changes, the relative positional relationship may also change accordingly.

[0027] like Figures 1 to 3 As shown, a cold-region tunnel entrance air curtain insulation system utilizing geothermal energy is disclosed, comprising: a geothermal heat extraction device, the geothermal heat extraction device comprising a heat extraction borehole 7 opened in the surrounding rock of the middle section of the tunnel and a heat extraction pipe 8 arranged inside the heat extraction borehole 7, the interior of the heat extraction pipe 8 containing a heat extraction medium; a curved air curtain unit, the curved air curtain unit comprising air curtain machines 3 uniformly arranged in a circumferential direction along the inner side of the tunnel entrance lining, the air curtain machine having an air curtain machine fixedly connected to the inner side of the tunnel entrance lining The outer shell 9, the interior of the air curtain shell 9 is provided with an air heating chamber 10, and a fan 11 is provided below the air heating chamber 10. The fan 11 drives the cold air at the tunnel entrance to pass through the air heating chamber 10 for heating and then guides it into the tunnel, forming a hot air curtain wall 4 on the cross section of the tunnel; and the ground source heat pump 15, the ground source heat pump 15 is respectively connected to the geothermal energy heat extraction device and the curved air curtain unit, and the ground source heat pump 15 uses geothermal energy as a heat source to provide heat energy to the air heating chamber 10.

[0028] In the above embodiment, clean and green geothermal energy is combined with air curtain technology to achieve long-term prevention of freezing damage at tunnel entrances in cold regions. A ground-source heat pump 15 uses geothermal energy as a heat source to provide heat to the air heating chamber 10. A fan 11 drives cold air from the tunnel entrance through the air heating chamber 10, heating it and then directing it into the tunnel. A hot air curtain wall is formed on the tunnel's cross section, preventing cold energy from outside the tunnel from being transferred into the tunnel, ensuring safety and without affecting vehicle operation. This system has low energy consumption and can achieve tunnel insulation during winter operation throughout the lifecycle of cold region tunnel projects. The air curtain is installed on the inner wall of the tunnel lining. For existing tunnels, heat extraction boreholes can be set within the tunnel's transverse passages, enabling retrofitting of existing tunnels for long-term freezing protection and insulation. For newly built tunnels, the insulation system of the present invention can be installed after the completion of the first lining of the entrance tunnel and can be used long-term during construction and operation. The curved air curtain unit utilizes geothermal energy to increase the temperature of the air curtain wall formed by the curved air curtain unit, thereby improving the efficiency of the air curtain technology in blocking cold air from outside the tunnel.

[0029] In the above embodiment, the tunnel portal lining 2 is arranged on the tunnel portal surrounding rock 1, and the air curtain machine 3 is installed and fixed on the tunnel portal lining 2 by expansion bolts or the like.

[0030] In some embodiments, as Figure 4 As shown, the interior of the air heating chamber 10 is provided with fins 20 and a curved water pipe 19, and the fins 20 are thermally connected to the curved water pipe 19. The fins 20 can increase the heat exchange area between the air and the air, thereby improving the heat exchange efficiency; the air curtain housing 9 is provided with a heat exchange medium inlet 13 and a heat exchange medium outlet 14 respectively connected to the two ends of the curved water pipe 19; the heat exchange medium inlet 13 and the heat exchange medium outlet 14 are connected to the ground source heat pump 15 through a water pipe pipeline; after the ground source heat pump 15 absorbs heat from the underground, it is heated by the compressor and supplies heat to the curved water pipe 19 in the air heating chamber 10, and the curved water pipe 19 and the fins 20 transfer heat, thereby increasing the heat transfer area between the air and the air, thereby improving the heating efficiency of the air.

[0031] In some embodiments, an electric heating component is provided inside the air heating chamber 10, and the electric heating component is used to assist in air heating under extremely cold conditions; wherein the electric heating component can select a point heating wire, and the electric heating wire generates heat when energized to assist in heating the air inside the air heating chamber 10 to harden the extremely cold environment.

[0032] In some embodiments, the cold region tunnel entrance air curtain insulation system using geothermal energy also includes a controller, to which a first temperature sensor, a second temperature sensor, and a third temperature sensor are connected. The first temperature sensor is used to detect the temperature inside the tunnel, the second temperature sensor is used to detect the temperature outside the tunnel, and the third temperature sensor is used to detect the temperature inside the air heating chamber. The controller is used to control the speed of the fan and can adjust the speed of the fan according to the temperature inside and outside the tunnel and the temperature inside the air heating chamber to adapt to different climate changes and different temperature requirements inside the tunnel.

[0033] In some embodiments, the geothermal heat pump 15 has a water pump unit 16 and a geothermal heat pump control panel 17. The geothermal heat pump 15 is connected to the heat extraction pipe 8, and obtains geothermal energy in the tunnel middle section surrounding rock 18 below the tunnel middle section lining 5 through the heat extraction pipe 8.

[0034] In some embodiments, the water pump unit 16 is connected to the heat extraction pipe 8 through a heat transfer pipeline, and the water pump unit 16 drives the heat extraction medium inside the heat extraction pipe 8 to circulate, thereby obtaining geothermal energy.

[0035] In some embodiments, the outside of the heat transfer pipeline is wrapped with thermal insulation cotton with a thickness of at least 10 mm, so as to reduce heat loss of the heat transfer pipeline during the transportation process.

[0036] In some embodiments, as Figure 2 As shown, insulation side trenches 6 are provided on both sides of the interior of the tunnel, and the heat transfer pipeline is laid inside the insulation side trenches 6. The insulation side trenches 6 further enhance the insulation effect of the heat transfer pipeline and reduce its heat loss.

[0037] In some embodiments, the heat pipe 8 is a U-shaped heat pipe. After the heat pipe 8 is installed in place inside the heat extraction borehole 7, the inside of the heat extraction borehole 7 is backfilled with a high thermal conductivity self-leveling material to fix the heat pipe 8 inside the heat extraction borehole 7, and at the same time form a heat conduction path between the surrounding rock and the heat extraction pipe 8; specifically, the high thermal conductivity self-leveling material is a high thermal conductivity silica sand self-leveling or an alumina-reinforced cement-based self-leveling.

[0038] In some embodiments, a guide fan blade 12 is provided below the fan 11. The fan 11 drives the cold air at the tunnel entrance to pass through the air heating chamber 10 for heating and then guide it into the tunnel by the guide fan blade 12. The air outlet direction of the air curtain machine 3 can be adjusted by the guide fan blade 12.

[0039] In the above embodiment, the heat medium may be water, 20-30% ethylene glycol solution, or the like.

[0040] Thus far, various embodiments of the present invention have been described in detail. To avoid obscuring the concept of the present invention, some details well known in the art have not been described. Based on the above description, those skilled in the art can fully understand how to implement the technical solutions disclosed herein.

[0041] The above-described embodiments represent only some embodiments of the present invention. Although the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the patent. It should be noted that a person skilled in the art may make various modifications and improvements without departing from the scope of the present invention, and these modifications and improvements fall within the scope of protection of the present invention. Therefore, the scope of protection of the patent for this invention shall be based on the appended claims.

Claims

1. A cold region tunnel entrance air curtain insulation system using geothermal energy, characterized in that: include: A geothermal heat extraction device, comprising a heat extraction borehole opened in the surrounding rock of the middle section of the tunnel and a heat extraction pipe arranged in the heat extraction borehole, wherein the heat extraction pipe has a heat extraction medium inside; A curved air curtain unit, wherein the curved air curtain unit comprises air curtain units evenly arranged along the inner side of the tunnel entrance lining, the air curtain units having an air curtain unit housing fixedly connected to the inner side of the tunnel entrance lining, an air heating chamber provided within the air curtain unit housing, and a fan provided below the air heating chamber. The fan drives cold air from the tunnel entrance through the air heating chamber for heating, and then guides the heated air into the tunnel, thereby forming a hot air curtain wall on the cross section of the tunnel; as well as, A ground source heat pump is connected to the geothermal heat extraction device and the arc-shaped air curtain unit respectively, and the ground source heat pump uses geothermal energy as a heat source to provide heat energy to the air heating chamber.

2. The cold region tunnel entrance air curtain insulation system utilizing geothermal energy according to claim 1 is characterized by: The air heating chamber is provided with fins and curved water pipes inside, and the fins are heat-conductingly connected to the curved water pipes; The air curtain housing is provided with a heat exchange medium inlet and a heat exchange medium outlet respectively connected to the two ends of the curved water pipe; The heat exchange medium inlet and the heat exchange medium outlet are connected to the ground source heat pump through water pipes.

3. The cold region tunnel entrance air curtain insulation system utilizing geothermal energy according to claim 1 is characterized by: An electric heating component is provided inside the air heating cavity, and the electric heating component is used to heat the air passing through the air heating cavity.

4. The cold region tunnel entrance air curtain insulation system utilizing geothermal energy according to claim 1 is characterized by: It also includes a controller, to which a first temperature sensor, a second temperature sensor, and a third temperature sensor are connected. The first temperature sensor is used to detect the air temperature inside the tunnel, the second temperature sensor is used to detect the air temperature outside the tunnel, and the third temperature sensor is used to detect the air temperature inside the air heating chamber. The controller is used to control the speed of the fan.

5. The cold region tunnel entrance air curtain insulation system utilizing geothermal energy according to claim 1 is characterized by: The ground source heat pump comprises a water pump unit and a ground source heat pump control panel, and the ground source heat pump is connected to the heat extraction pipe.

6. The cold region tunnel entrance air curtain insulation system utilizing geothermal energy according to claim 5 is characterized by: The water pump unit is connected to the heat extraction pipe through a heat transfer pipeline.

7. The cold region tunnel entrance air curtain insulation system utilizing geothermal energy according to claim 6 is characterized by: The outer side of the heat transfer pipeline is wrapped with thermal insulation cotton with a thickness of at least 10 mm.

8. The cold region tunnel entrance air curtain insulation system utilizing geothermal energy according to claim 6 is characterized by: Insulation side trenches are provided on both sides of the interior of the tunnel, and the heat transfer pipeline is laid inside the insulation side trenches.

9. The cold region tunnel entrance air curtain insulation system utilizing geothermal energy according to claim 1 is characterized by: The heat extraction pipe is a U-shaped heat extraction pipe. After the heat extraction pipe is installed in place inside the heat extraction drilled hole, the inside of the heat extraction drilled hole is backfilled with a self-leveling material with high thermal conductivity.

10. The cold region tunnel entrance air curtain insulation system utilizing geothermal energy according to claim 1 is characterized by: The fan is provided with a guide fan blade below the fan, and the fan drives the cold air at the tunnel entrance to pass through the air heating chamber for heating and then guide the cold air into the tunnel by the guide fan blade.

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