Energy Storage and Regulation Type Dual-Outlet Air Curtain Insulation and Antifreeze Device and Method for Tunnel Entrance in Cold Regions

Abstract

This invention belongs to the technical field of tunnel frost damage prevention and control, and discloses a dual-outlet air curtain insulation and anti-freezing device for tunnel entrances in cold regions. It includes an air curtain insulation unit, a phase change energy storage unit, and a temperature control unit. The air curtain insulation unit includes an air inlet, an air duct, an air outlet, and a fan, and the air outlet has two outlets pointing out of and into the tunnel, respectively. When the monitored temperature is higher than or equal to the phase change temperature of the phase change material, the energy storage mode is activated, the nozzle pointing into the tunnel opens, and the phase change material absorbs heat and stores energy. When the monitored temperature is lower than the phase change temperature of the phase change material, the insulation mode is activated, the nozzle pointing out of the tunnel opens, forming an air curtain that blocks external airflow. This invention also discloses a corresponding method. Through this invention, the seasonal and diurnal temperature fluctuations in cold regions are fully utilized to regulate natural energy and block cold air from outside the tunnel, achieving a two-pronged approach to prevent frost damage.

Description

Technical Field

[0001] This invention belongs to the technical field of tunnel frost damage prevention and control, and more specifically, relates to a cold-region tunnel entrance energy storage and regulation type double-outlet air curtain insulation and antifreeze device and method. Background Technology

[0002] In recent years, the number of tunnel projects in cold regions has been increasing. In tunnels built in these areas, the various drainage pipes after the tunnel lining are often frozen and damaged due to the influence of cold air at the tunnel entrance. This causes poor drainage, with large amounts of water flowing to the ground or accumulating behind the lining. The water flowing to the ground freezes into ice, seriously affecting vehicle traffic, while the water accumulating behind the lining freezes and expands, damaging the lining and affecting the structural safety of the tunnel.

[0003] The inflow of cold air is a significant factor contributing to frost damage in tunnels in cold regions. The driving forces behind natural airflow are primarily wind pressure and thermal pressure. Although the natural winds in the tunnel area may be strong, wind pressure at the tunnel entrance is often low due to topographical obstruction and other factors, with airflow mainly driven by thermal pressure ventilation. When the temperature rises, both the temperature inside and outside the tunnel rises, with a more significant rise outside the tunnel. The thermal pressure inside the tunnel is higher than outside, causing hot air to flow outwards. Conversely, when the temperature drops, both the temperature inside and outside the tunnel decrease, with a more significant decrease outside the tunnel. The thermal pressure outside the tunnel is higher than inside, causing cold air to flow into the tunnel. This unique airflow pattern in tunnels contributes to frost damage in cold-region tunnels.

[0004] To address the aforementioned problem of frost damage at tunnel entrances, numerous remedial measures have been implemented in the past, such as laying insulation layers and adding electric heating panels. However, these methods neglect the root cause of tunnel frost damage—the inflow of cold air—and thus have failed to achieve satisfactory results. To prevent the intrusion of cold air from outside the tunnel, air curtain technology, commonly used in air conditioning systems to separate airflow, is an effective means. Patent searches reveal that existing technologies have proposed a limited number of solutions using air curtains to prevent frost damage at tunnel entrances. For example, CN202011242580.7 proposes a tunnel high-pressure air curtain experimental device, method, and system; CN201710333747.2 discloses an independent pressurized air supply system and air supply method for tunnel cross passages; CN201810171427.6 proposes an air curtain experimental device and experimental method for high-speed railway tunnels in cold regions, and so on.

[0005] However, further research has shown that the existing technologies still have the following defects or deficiencies: First, the existing air curtain-like forms can only achieve simple air isolation or smoke isolation functions. They only focus on blocking cold air outside the tunnel, and often lack sufficient resistance to cold air entering the tunnel due to traffic flow, strong winds, etc., resulting in low device reliability. Second, the existing air curtain-like forms usually consume a lot of energy and fail to fully consider the rational use of energy when the air temperature outside the tunnel is high. They also have problems such as inconvenient installation and operation, and poor cold insulation and antifreeze effects. Summary of the Invention

[0006] In view of the above-mentioned defects or needs of the existing technology, the purpose of this invention is to provide a cold-region tunnel entrance energy storage and regulation type double-outlet air curtain insulation and anti-freezing device and method. The device redesigns the overall structure and the setting of some key modules, and in particular, takes into account the working characteristics of the tunnel entrance in cold regions to make full use of temperature fluctuations to introduce an energy storage and regulation type air curtain. This can more effectively solve the existing problem of freezing damage in high-speed railway tunnels in cold regions, and has the advantages of compact structure, high efficiency and energy saving, easy operation and good environmental adaptability.

[0007] To achieve the above objectives, according to one aspect of the present invention, a dual-outlet air curtain insulation and antifreeze device for energy storage and regulation at tunnel entrances in cold regions is provided. The device is characterized in that it is arranged in pairs on both sides of the tunnel entrance and includes an air curtain insulation unit, a phase change energy storage unit, and a temperature control unit, wherein:

[0008] The air curtain insulation unit includes an air inlet, an air duct, an air outlet, and a fan. The air inlet is located on the concrete wall of the tunnel and is used to introduce air from outside the tunnel. One end of the air duct is connected to the air inlet, and the other end is connected to the air outlet. The air outlet has two outlets, with the first outlet pointing out of the tunnel and the second outlet pointing into the tunnel. The fan is installed inside the air duct.

[0009] The phase change energy storage unit is composed of components filled with phase change material, and it is installed inside the tunnel and near the air curtain insulation unit.

[0010] The temperature control unit is used to monitor the temperature at the air inlet. When the monitored temperature is higher than or equal to the phase change temperature of the phase change material, the second outlet and the fan are activated to send outside air into the tunnel, where the phase change material absorbs heat and stores energy. When the monitored temperature is lower than the phase change temperature of the phase change material, the first outlet and the fan are activated to spray airflow to form a cooling air curtain at the tunnel entrance.

[0011] As a further preferred embodiment, for the air curtain insulation unit, the air inlets, air ducts and air outlets located on both sides of the tunnel entrance are symmetrically arranged about the central axis of the tunnel.

[0012] As a further preferred embodiment, the air duct of the air curtain insulation unit is preferably made of metal and is prefabricated in the factory and then installed on site.

[0013] As a further preferred embodiment, for the air curtain insulation unit, its first outlet and second outlet are preferably in the form of slotted nozzles, and the first outlet forms a first angle of 10° to 20° with the tunnel cross-section, and the second outlet forms a second angle of 30° to 50° with the tunnel cross-section.

[0014] As a further preferred embodiment, the phase change energy storage unit preferably adopts the form of a hollow structural plate, which has a connecting pipe and a connecting groove. The connecting pipe is used to inject the phase change material into the interior of the hollow structural plate, and after the pipe opening is closed, it is inserted into the connecting groove of an adjacent hollow structural plate to complete the assembly.

[0015] As a further preferred embodiment, the phase change energy storage unit is preferably arranged within a range of 50m from the location of the air curtain insulation unit in the direction into the tunnel, and can be used as a tunnel lining or as an independent energy storage unit.

[0016] As a further preferred embodiment, the phase change material of the phase change energy storage unit preferably has a phase change temperature of 0°C to 5°C, and the thickness of the phase change material layer is 10cm to 20cm.

[0017] As a further preferred embodiment, the phase change material of the phase change energy storage unit is preferably a mixture of n-decyl alcohol and palmitic acid or liquid paraffin TH-SL2.

[0018] As a further preferred embodiment, the temperature control unit preferably includes a temperature sensor, a signal transmission line, and a temperature control valve. The temperature sensor is used to monitor the temperature at the air inlet, and then transmits the monitoring signal to the temperature control valve through the signal transmission line. The temperature control valve is used to independently drive the fan, the first outlet, and the second outlet to open or close them.

[0019] As a further preferred embodiment, the tunnel entrance is preferably enlarged into a rectangle in cross-section, while its outermost end face is reduced back to its original shape.

[0020] According to another aspect of the present invention, a corresponding air curtain insulation and antifreeze method is also provided, characterized in that the device is arranged at the entrance of a tunnel in a cold region, and can then operate in different working modes according to different working conditions:

[0021] In the energy storage working mode, the second outlet and the fan are turned on, and air from outside the tunnel enters the tunnel, which then melts the phase change material in the phase change energy storage unit, thereby achieving heat absorption and energy storage.

[0022] In the cold insulation working mode, the first outlet and the fan are turned on. Air from outside the tunnel is introduced through the air inlet and sprayed outward from the first outlet through the air duct, thereby forming a cold insulation air curtain at the tunnel entrance.

[0023] In summary, the technical solutions conceived by this invention have the following main technical advantages compared with the prior art:

[0024] (1) This invention fully considers the environment of tunnels in cold regions and utilizes the energy of the cold environment during the warm season and when the daytime air temperature is high. By setting up a phase change energy storage unit, this part of the energy is effectively stored to resist the cooling caused by the cold air entering the tunnel when the air temperature is low during the cold season and at night. This effectively prevents tunnel freezing damage in a green and energy-saving way.

[0025] (2) By setting up a dual outlet of the air curtain and a temperature control unit, the present invention monitors the air intake temperature by a temperature sensor and controls the valve to select the opening and closing of the first outlet and the second outlet, thereby realizing the automatic switching between the energy storage mode and the insulation mode of the air curtain insulation and antifreeze device, accurately identifying the environmental conditions to determine a reasonable working mode, and significantly improving the overall insulation effect at the tunnel entrance.

[0026] (3) The energy storage and regulation type double-outlet air curtain insulation and antifreeze device of the present invention has high reliability and strong environmental adaptability. By effectively storing energy when the ambient temperature is high, it effectively resists the cooling caused by cold air entering the tunnel due to factors such as traffic flow and strong wind, which improves the reliability of the system. It can adapt to different environments and the frost damage prevention effect is significantly improved compared with the traditional single air curtain insulation mode. Attached Figure Description

[0027] Figure 1 This is a schematic diagram illustrating the air curtain insulation and antifreeze device of the present invention arranged on one side of a tunnel entrance in a cold region.

[0028] Figure 2 This is a structural cross-sectional view used to demonstrate the air curtain insulation and antifreeze device according to the present invention;

[0029] Figure 3 This is a three-dimensional structural view of a phase change energy storage unit according to a preferred embodiment of the present invention;

[0030] Figure 4 yes Figure 3 The diagram shows the structural plan of the phase change energy storage unit.

[0031] In all the accompanying drawings, the same reference numerals are used to denote the same elements or structures, wherein:

[0032] 1-Tunnel concrete wall; 2-Air duct; 3-Fan; 4-First outlet; 5-Second outlet; 6-Temperature sensor; 7-Signal transmission line; 8-Temperature control valve; 9-Airflow; 10-Tunnel central axial surface; 11-Connecting pipe; 12-Connecting groove; 13-Structural slab concrete; 14-Phase change material. Detailed Implementation

[0033] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0034] Figure 1 This is a schematic diagram illustrating the illustrative arrangement of the air curtain insulation and antifreeze device of the present invention on one side of a tunnel entrance in a cold region. (See diagram for example.) Figure 1 As shown, the device is arranged in pairs on both sides of the tunnel entrance and mainly includes components such as an air curtain insulation unit, a phase change energy storage unit, and a temperature control unit. These will be explained in detail below.

[0035] For air curtain insulation units, such as Figure 1 and Figure 2 As shown, it includes an air inlet, an air duct 2, an air outlet, and a fan 3. The air inlet is located on the concrete wall 1 of the tunnel and is used to introduce air from outside the tunnel. One end of the air duct 2 is connected to the air inlet, and the other end is connected to the air outlet. The air outlet has two outlets, with the first outlet 4 pointing out of the tunnel and the second outlet 5 pointing into the tunnel. The fan 3 is installed inside the air duct 2.

[0036] The phase change energy storage unit consists of a structure filled with phase change material, which is installed inside the tunnel and arranged near the air curtain insulation unit.

[0037] The temperature control unit is used to monitor the temperature at the air inlet. When the monitored temperature is higher than or equal to the phase change temperature of the phase change material, it drives the second outlet and the fan to open, sending air from outside the tunnel into the tunnel, where the phase change material absorbs heat and stores energy. When the monitored temperature is lower than the phase change temperature of the phase change material, it drives the first outlet and the fan to open, spraying airflow to form a cooling air curtain at the tunnel entrance.

[0038] Based on the above concepts, this invention primarily addresses the problem of frost damage in tunnels in cold regions from two aspects. Firstly, it utilizes an air curtain insulation and anti-freezing device to directly block cold air flowing into the tunnel. Secondly, it employs a phase change energy storage unit to store energy from the warm air outside the tunnel when the temperature is higher. The stored energy effectively counteracts the cooling caused by cold air entering the tunnel due to factors such as traffic flow and strong winds, thus ensuring high system reliability. Because it simultaneously blocks cold air and stores and utilizes warm air, the frost damage prevention effect is superior to traditional air curtain insulation methods.

[0039] More specifically, such as Figure 1 As shown in the exemplary embodiment, the air inlet is preferably directly installed on the tunnel concrete wall 1 and used to introduce air from outside the tunnel. The air duct 2 is preferably made of metal and contains a fan 3, both of which can be prefabricated in the factory. The concrete outside the air duct 2 can be prefabricated in the factory or constructed on-site with pre-embedded bolts for subsequent installation. After the above components are prefabricated, they can be debugged in the factory. Based on the actual dimensions of the tunnel, the parameters of the fan and air curtain outlets are determined to ensure that the jets sprayed from the outlets can merge with the jets from the outlets on the opposite side of the tunnel after reaching the central axis surface 10 to form a closed air curtain.

[0040] Accordingly, under the power of the independently controllable fan 3, air from outside the tunnel enters the air duct, and the flow direction of the airflow 9 is described by the arrow in the figure. According to a preferred embodiment of the present invention, the air curtain outlet is preferably in the form of two slotted nozzles, wherein the first outlet 4 is directed out of the tunnel at a relatively small first angle of, for example, 10° to 20° with the tunnel cross-section to form a closed air curtain, and the second outlet 5 is directed into the tunnel at a relatively large second angle of, for example, 30° to 50° with the tunnel cross-section to deliver air into the depth of the tunnel.

[0041] like Figure 3 and Figure 4 As illustrated in the example, the phase change energy storage unit preferably adopts the form of a hollow structural plate, which for example has a connecting pipe 11 and a connecting groove 12. The connecting pipe 11 is used to inject the phase change material into the interior of the hollow structural plate, and after the pipe opening is closed, it is inserted into the connecting groove 12 of an adjacent hollow structural plate to complete the assembly.

[0042] More specifically, the hollow structural slab can be prefabricated directly in the factory, serving both as a lining and as an energy storage container. The connecting pipe 11 is inserted into the connecting groove 12 of another hollow structural slab, and the joint is treated to enable rapid on-site assembly. The connecting pipe 11 also serves as a phase change material injection pipe; after injecting the phase change material into the hollow area inside the hollow structural slab, the pipe opening is sealed. 13 represents the structural slab concrete. In energy storage mode, the phase change material 14 melts to store energy from the hot air outside the tunnel; in insulation mode, it freezes to resist cold air flowing into the tunnel due to various factors, regulating natural energy and preventing frost damage at tunnel entrances in cold regions.

[0043] According to another preferred embodiment of the present invention, the phase change material 14 is preferably set to a phase change temperature of 0°C to 5°C, the latent heat of phase change is as large as possible, the thickness of the phase change material layer is preferably 10cm to 20cm, and it is preferably laid within 50m from the location of the cooling insulation unit into the tunnel on the inner side of the tunnel entrance. Phase change materials within this phase change temperature range, such as n-decyl alcohol-palmitic acid 97:3 mixture (phase change temperature 3.9°C, latent heat 254.1J / g) and liquid paraffin TH-SL2 (phase change temperature 3.28°C, 168.2J / g), can be selected.

[0044] Numerous practical engineering tests have shown that the above-mentioned operating parameters can better utilize the energy storage and insulation effects of the energy storage and regulating type air curtain insulation and antifreeze device according to the present invention, and ensure that the temperature behind the hollow structure plate is always maintained above 0°C when cold air that can penetrate into the tunnel in various ways does not cause the phase change material to freeze completely.

[0045] Furthermore, in this invention, the two nozzles and the fan are equipped with temperature control units for independent control. According to another preferred embodiment of the invention, the temperature control unit may consist of a temperature sensor 6, a signal transmission line 7, and a temperature control valve 8. When the temperature sensor 6 detects that the air temperature at the air inlet of the air curtain exceeds the phase change temperature of the phase change material 14, the second outlet 5 pointing into the tunnel is opened under the control of the temperature control valve 8, and the air curtain jet sends hot air into the tunnel for energy storage; when the temperature sensor 6 detects that the air temperature at the air inlet of the air curtain is lower than the phase change temperature of the phase change material 14, the first outlet 4 pointing out of the tunnel is opened under the control of the temperature control valve 8, at which time the air curtain jet blocks the inflow of external cold air.

[0046] According to another preferred embodiment of the present invention, the air curtain insulation device can be configured with a rectangular cross-section at the tunnel entrance. Since the air curtain vent has straight edges, for ease of installation, the tunnel cross-section can preferably be expanded into a rectangle at the tunnel exit, while the exit is reduced to its original shape at the outermost end face.

[0047] The working process of the device according to the present invention will be explained in detail below.

[0048] The device of the present invention has two operating modes: an energy storage mode and a barrier mode. The switching between the two modes is controlled by the temperature monitoring feedback of the air curtain inlet.

[0049] More specifically, when the air inlet temperature of the air curtain is higher than the phase change temperature of the phase change material, the energy storage mode is activated. At this time, the nozzles pointing into the tunnel operate, sending hot air from outside the tunnel into the tunnel, causing the phase change material to melt and store energy. Conversely, when the air inlet temperature of the air curtain is lower than the phase change temperature of the phase change material, the barrier mode is activated. The nozzles flowing out of the tunnel operate, forming a closed air curtain at the tunnel entrance to block the inflow of cold air from outside. Cold air entering the tunnel due to factors such as traffic flow and strong winds causes some of the phase change material to freeze. During this process, the phase change material can release the stored energy to resist the cooling, significantly improving the reliability of tunnel freezing damage prevention.

[0050] In other words, this invention recognizes that the root cause of frost damage at tunnel entrances in cold regions is the inflow of cold air. Therefore, this invention differs from traditional air curtain devices by setting up phase change energy storage units within a certain range at the tunnel entrance and setting up double-outlet air curtains on both sides of the tunnel entrance. This allows for the full utilization of natural energy and the blocking of cold air, thereby achieving the purpose of controlling frost damage at tunnel entrances. The working mode of the device is determined according to the air inlet temperature of the air curtain. When the air inlet temperature is high, it enters the energy storage mode, and when the air inlet temperature is low, it enters the air curtain blocking mode. By combining energy storage and blocking, frost damage at tunnel entrances is prevented.

[0051] In this way, the present invention fully incorporates the characteristics of the air outside the tunnel in cold regions, such as the periodic fluctuations of air with the seasons and day and night. When the temperature is high, the energy in the air should be fully utilized, which is achieved through the phase change energy storage unit. When the temperature is low, the cold air outside the tunnel should be prevented from flowing into the tunnel, which is achieved through the dual-outlet air curtain.

[0052] In summary, the energy storage and regulation type dual-outlet air curtain insulation and antifreeze device according to the present invention has high reliability, is green and energy-saving, has automated operation, and strong environmental adaptability. It can smoothly switch between different working modes by relying on the automatic control of only a few components. It is a low-energy-consumption and high-quality air curtain insulation method, and is therefore particularly suitable for frost damage prevention and control applications such as tunnel entrances in cold regions, and has broad application prospects.

[0053] Those skilled in the art will readily understand that the above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A dual-outlet air curtain insulation and antifreeze device for energy storage and regulation at tunnel entrances in cold regions, characterized in that, The air curtain insulation and antifreeze device is arranged in pairs on both sides of the tunnel entrance and includes an air curtain insulation unit, a phase change energy storage unit, and a temperature control unit, wherein: The air curtain insulation unit includes an air inlet, an air duct (2), an air outlet, and a fan (3). The air inlet is located on the tunnel concrete wall (1) and is used to introduce air from outside the tunnel. One end of the air duct (2) is connected to the air inlet, and the other end is connected to the air outlet. The air outlet has two outlets, with the first outlet (4) pointing out of the tunnel and the second outlet (5) pointing into the tunnel. The fan (3) is installed inside the air duct (2). In addition, the air inlet, air duct (2), and air outlet on both sides of the tunnel entrance are symmetrically arranged about the tunnel's central axis. The first outlet (4) and the second outlet (5) are in the form of slotted nozzles. The first outlet (4) forms a first angle of 10° to 20° with the tunnel cross-section, and the second outlet (5) forms a second angle of 30° to 50° with the tunnel cross-section. The phase change energy storage unit is composed of components filled with phase change material, and it is installed inside the tunnel and near the air curtain insulation unit. The temperature control unit is used to monitor the temperature at the air inlet. When the monitored temperature is higher than or equal to the phase change temperature of the phase change material, the second outlet and the fan are activated to send outside air into the tunnel, and the phase change material absorbs heat and stores energy. When the monitored temperature is lower than the phase change temperature of the phase change material, the first outlet and the fan are activated to spray airflow to form a cold-insulating air curtain at the tunnel entrance. The cold insulation and antifreeze device is installed at the entrance of a cold-region tunnel. The tunnel entrance is designed to have a rectangular cross-section, which is then reduced to its original shape at its outermost end. The cold insulation and antifreeze device operates in different modes according to different working conditions. In the energy storage working mode, the second outlet and the fan are turned on, and air from outside the tunnel enters the tunnel, which then melts the phase change material in the phase change energy storage unit, thereby achieving heat absorption and energy storage. In the cold insulation working mode, the first outlet and the fan are turned on. Air from outside the tunnel is introduced through the air inlet and sprayed outward from the first outlet through the air duct, thereby forming a cold insulation air curtain at the tunnel entrance.

2. The apparatus as claimed in claim 1, characterized in that, For the air curtain insulation unit, its air duct (2) is made of metal and is prefabricated in the factory and then installed on site.

3. The apparatus as described in claim 2, characterized in that, The phase change energy storage unit adopts the form of a hollow structure plate, which has a connecting pipe (11) and a connecting groove (12). The connecting pipe (11) is used to inject the phase change material into the interior of the hollow structure plate, and after the pipe opening is closed, it is inserted into the connecting groove (12) of another adjacent hollow structure plate to complete the assembly.

4. The apparatus as described in claim 3, characterized in that, The phase change energy storage unit is arranged within a range of 50m from the location of the air curtain insulation unit in the direction into the tunnel, and can be used as tunnel lining or as an independent energy storage unit.

5. The apparatus as described in claim 4, characterized in that, For the phase change energy storage unit, its phase change material has a phase change temperature of 0℃ to 5℃, and the thickness of the phase change material layer is 10cm to 20cm.

6. The apparatus according to any one of claims 1-5, characterized in that, The temperature control unit includes a temperature sensor (6), a signal transmission line (7), and a temperature control valve (8). The temperature sensor (6) is used to monitor the temperature at the air inlet and then transmit the monitoring signal to the temperature control valve (8) through the signal transmission line (7). The temperature control valve (8) is used to independently drive the fan (3), the first outlet (4), and the second outlet (5) to open or close them.

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