A tunnel aerodynamic effect mitigation device with a self-sustaining power supply system

Abstract

A tunnel aerodynamic effect mitigation device with a self-sustaining power supply system. Heating devices for heating the air inside the tunnel are arranged at both ends of the tunnel with the tunnel entrance as the starting end. The heating devices inside the tunnel are divided into multiple continuously arranged heating sections along the tunnel length direction, and each heating section can be independently controlled to open and close. By increasing the temperature of the air inside the tunnel through the heating zone, the piston effect and friction effect when the train enters the tunnel are reduced, and the aerodynamic effect inside the tunnel is alleviated. Additionally, since each heating section can be independently controlled to open and close, by turning on different numbers of heating sections, it is possible to adapt to trains of different lengths and train streamline shapes, achieve precise heating, and improve the energy utilization efficiency. At the same time, through the train wind power generation self-sustaining system, wind turbines are installed at certain intervals on both sides of the track inside the tunnel. The train wind generated when the train passes will drive the wind turbines to rotate and generate electric energy, providing energy for the heating mitigation system, so that the entire system can achieve self-sustaining characteristics on the basis of consuming a small amount of external energy.

Description

Technical Field

[0001] The present invention relates to a tunnel aerodynamic effect mitigation device with a self-sustaining power supply system. Background Art

[0002] The aerodynamic effect when a high-speed train passes through a tunnel refers to that when the train enters the tunnel, a huge piston effect is generated, causing the air in front of the train to be violently compressed to form a compression wave. This compression wave is transmitted to the tunnel exit to form a micro-pressure wave, which further intensifies into a pressure blast wave. On the one hand, the pressure blast wave emits a violent noise, causing environmental pollution and seriously disturbing the lives of residents around the tunnel entrance. On the other hand, the violently changing pressure wave in the tunnel acting on the vehicle body and the tunnel surface will also affect the running safety of the train. It may even damage the vehicle body structure and tunnel facilities, and the external pressure transmitted into the vehicle will also cause discomfort to passengers, seriously affecting passenger comfort. Since the magnitude of the pressure wave in the tunnel mainly depends on the blockage ratio (the ratio of the cross-sectional area of the train to the cross-sectional area of the tunnel), and the maximum value of the micro-pressure wave outside the tunnel is positively correlated with the pressure gradient of the initial compression wave, there are the following two solutions for mitigating the tunnel aerodynamic effect in the prior art:

[0003] 1. For the micro-pressure wave, it is usually considered an economical and effective method to set up buffer structures (such as auxiliary facilities like vertical shafts, inclined shafts or cross tunnels, etc.) to reduce the transient pressure in the tunnel. Currently, buffer facilities for reducing the micro-pressure wave include various new types of beveled tunnel portals or buffer structures such as inner stepped types. At the same time, the method of lengthening the streamlined length of the train is used to reduce the pressure gradient of the initial compression wave, but the effect of reducing the maximum value of the compression wave is not obvious. Vertical shafts and inclined shafts can reduce the pressure fluctuation in the tunnel and also mitigate the micro-pressure wave outside the tunnel. However, the positions of the vertical shafts and inclined shafts for mitigating the pressure fluctuation and the micro-pressure wave are different. The same vertical shaft cannot achieve the optimal mitigation of the pressure fluctuation and the micro-pressure wave. Moreover, most of the vertical shafts, inclined shafts or cross tunnels are measures forced to be taken during ventilation, rescue or due to terrain conditions during design. Therefore, the design parameters are limited in terms of the effect of mitigating the aerodynamic effect.

[0004] 2. A tunnel structure with a variable cross-section is adopted. For example, in the patent application with the application number 201810416498.8 and the invention title "Variable Cross-Section Tunnel Structure for Alleviating Tunnel Aerodynamic Effects and Parameter Determination Method", it discloses a tunnel structure with a variable cross-section by setting an expansion section at the tunnel entrance and exit, which can alleviate the tunnel aerodynamic effects. Currently, the main operating speed of high-speed trains in China is 350 km / h. However, in the future, the operating speed of trains will be increased to 400 km / h or higher, and the speed of high-speed maglev will reach 600 km / h or higher. The pressure fluctuation in the tunnel is proportional to the square of the speed, and the pressure shock wave caused by micro-pressure intensification is to the 6th - 13th power of the vehicle speed. Therefore, when the vehicle speed increases, the aerodynamic effects will show a sharp increase. If only relying on the variable cross-section at the entrance and exit, the area of the expansion section will become very large, which will bring extremely high construction costs. For example, a 100-square-meter tunnel cross-sectional area is 1.4 times that of a 70-square-meter one, but the construction cost is twice as much. As the tunnel cross-section increases, the span of the tunnel will increase, and the requirements for the supporting structure of the tunnel will also increase, resulting in a huge increase in costs. Moreover, it is difficult to achieve an unlimited increase in the cross-sectional area. Summary of the Invention

[0005] The present invention provides a tunnel aerodynamic effect mitigation device with a self-sustaining power supply system for alleviating tunnel aerodynamic effects by heating to solve the deficiencies of the prior art.

[0006] To achieve the above object, the present invention first proposes a tunnel aerodynamic effect mitigation device with a self-sustaining power supply system. Heating zones for heating the air in the tunnel are respectively arranged in the tunnel, starting from the tunnel openings at both ends of the tunnel. The heating zones in the tunnel are divided into a plurality of continuously arranged heating segments along the tunnel length direction, and each heating segment can be independently controlled to be turned on or off. A plurality of wind power generation devices arranged along the tunnel length direction are also installed in the tunnel. The wind power generation devices are connected to a storage battery through a control system, and the storage battery supplies power to the heating zones through the control system.

[0007] With the above structure, the heating zone starts at the tunnel entrance. Before the train enters the tunnel, the heating zone is activated to heat the air in the tunnel to a certain temperature. Since the pressure wave amplitude consists of two parts: the piston effect and the friction between the train and the air. When the air temperature in the tunnel rises, the air density decreases. At this time, the piston effect when the train enters the tunnel weakens, and at the same time, the friction effect between the train and the air also weakens, resulting in a decrease in the pressure wave amplitude. The micro-pressure wave amplitude is positively correlated with the initial compression wave pressure gradient. As the air density decreases, the interaction between the train and the air when the train enters the tunnel decreases, and the initial compression wave pressure gradient also decreases, thus reducing the micro-pressure wave amplitude. Therefore, by raising the temperature of the tunnel through the heating zone, the aerodynamic effect in the tunnel can be alleviated. Since the tunnel pressure wave and the micro-pressure wave are mainly formed in the entrance section of the tunnel, the middle section of the tunnel mainly affects the propagation speed of the pressure wave, and the end of the tunnel affects the size of the pressure wave due to the occurrence of reflection and other phenomena in this area. Therefore, the heating zone starts from the tunnel entrance to ensure the best effect of alleviating the aerodynamic effect in the tunnel; in addition, since each heating section can be controlled to open and close independently, by opening different numbers of heating sections, it is possible to adapt to trains of different lengths, achieve precise heating, and improve the energy utilization efficiency.

[0008] By installing a wind power generation device in the tunnel, the wind generated when the train passes will drive the wind power generation device to rotate and generate electric energy, which is then stored in a battery. Thus, electric energy can be provided for the heating device to supplement a part of the energy consumed by the heating device, thereby reducing energy consumption while alleviating the aerodynamic effect.

[0009] In this embodiment, the total length of the continuously opened heating sections starting from the heating section at the tunnel entrance in the tunnel is the same as the streamlined length of the train head of the train to pass through the tunnel or the same as the length of the train body. With the above structure, if only the micro-pressure wave outside the tunnel needs to be alleviated, a heating zone with the same length as the streamlined length of the train head can be arranged only in the tunnel. If both the pressure fluctuation in the tunnel and the micro-pressure wave outside the tunnel need to be alleviated simultaneously, the length of the arranged heating zone is the same as the length of the train body, so that the energy consumption can be minimized to achieve the effect of alleviating the aerodynamic effect according to the requirements.

[0010] In this embodiment, the heating zones at both ends of the tunnel are opened simultaneously, so as to further alleviate the aerodynamic effect.

[0011] In this embodiment, heating devices are evenly arranged on each heating section. A temperature monitoring system is installed in the tunnel. Both the heating devices and the temperature monitoring system are connected to the control system. The temperature monitoring system monitors the temperature in the heating zone of the tunnel in real time. The control system controls the opening and closing time of the heating devices according to the real-time arrival time of the train and the temperature required in the tunnel. Through the control system, the heating devices are started when the train comes and closed after the train passes, thereby reducing energy consumption.

[0012] In this embodiment, before the train arrives at the tunnel, the heating section heats the air in the tunnel to 50°C to 100°C. The higher the temperature, the better the effect of alleviating the aerodynamic effect, and the heating time can be selected according to the external temperature conditions.

[0013] In this embodiment, the heating device is a heating sheet with a thickness of no more than 2 mm, and the heating sheet is fixed on the inner wall of the tunnel. In this way, when the heating device is installed, the influence on the inner diameter of the tunnel can be reduced, thereby improving the effect of alleviating the aerodynamic effect.

[0014] In this embodiment, multiple wind power generation devices are arranged at equal intervals and staggered on both sides of the track in the tunnel.

[0015] In summary, the present invention solves the problem of having to change the tunnel structure to alleviate the pressure fluctuation in the tunnel or the micro-pressure wave outside the tunnel. The air in the tunnel is heated by the heating device, and at the same time, the wind power generation device is used to generate electric energy to supplement part of the electric energy consumption of the heating device. In this way, without damaging the overall structure of the tunnel, the energy consumption is minimized to achieve the effect of alleviating the aerodynamic effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is the layout diagram of the heating area of the present invention.

[0017] Figure 2 It is the layout diagram of the wind power generation device of the present invention.

[0018] Figure 3 It is the schematic diagram of the present invention.

[0019] Figure 4 It is the relationship diagram between the pressure wave mitigation rate and the train length of the present invention.

[0020] Figure 5 It is the trend diagram of the wave mitigation rate in the tunnel in the first group of tests of the present invention.

[0021] Figure 6 It is the trend diagram of the wave mitigation rate in the tunnel in the second group of tests of the present invention.

[0022] Figure 7 It is the trend diagram of the wave mitigation rate in the tunnel in the third group of tests of the present invention.

[0023] In the drawings, 1, tunnel; 2, heating area; 3, wind power generation device. DETAILED DESCRIPTION OF THE INVENTION

[0024] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts belong to the scope of protection of the present invention.

[0025] In addition, the technical solutions between the various embodiments of the present invention can be combined with each other, but it must be based on the ability of those of ordinary skill in the art to implement. When the combination of technical solutions is contradictory or cannot be implemented, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

[0026] As Figures 1 to 3 shown, the present invention provides a tunnel aerodynamic effect mitigation device with a self-sustaining power supply system. In the tunnel 1, heating zones 2 for heating the air in the tunnel 1 are respectively arranged starting from the tunnel openings at both ends of the tunnel 1. The heating zones 2 in the tunnel 1 are divided into a plurality of continuously arranged heating segments along the length direction of the tunnel 1, and each heating segment can be individually controlled to open and close. In this embodiment, the total length of the continuously opened heating segments starting from the heating segment at the entrance of the tunnel 1 in the tunnel 1 is the same as the streamline length of the train head to pass through the tunnel 1 or the same as the train body length. Heating devices are evenly arranged on each heating segment. A temperature monitoring system is installed in the tunnel 1. The heating devices and the temperature monitoring system are both connected to the control system. The temperature monitoring system monitors the temperature in the heating zone 2 in the tunnel 1 in real time. The control system controls the opening and closing time of the heating devices according to the real-time arrival time of the train and the temperature required to be reached in the tunnel 1. Through the control system, when the train comes, the heating devices are started, and after the train leaves, the heating devices are closed, thereby reducing energy consumption. The temperature required to be reached in the tunnel 1 is 50°C to 100°C. The higher the temperature, the better the mitigation effect of the aerodynamic effect. The heating temperature can be selected according to the external temperature and the actual energy situation.

[0027] The present invention further includes a plurality of wind power generation devices 3 arranged along the length direction of the tunnel 1 in the tunnel 1. The wind power generation devices 3 are connected to the storage battery through the control system, and the storage battery is connected to the heating devices through the control system. In this embodiment, the plurality of wind power generation devices 3 are arranged at equal intervals and staggered on both sides of the track in the tunnel 1. By using the wind power generation devices 3, when the train passes through the tunnel 1, the wind will drive the wind power generation devices 3 to rotate at high speed to generate electric energy, and this part of the electric energy is stored in the storage battery and can supply electric energy to the heating devices, thereby reducing energy consumption while mitigating the aerodynamic effect. Embodiment

[0028] Taking a certain double-deck high-speed EMU as an example, the streamlined length of the train head is 12.5 m, the total length of the train body is 83 m, the train speed is 350 km / h, and the tunnel length is 350 m.

[0029] Pressure wave measurement points are set in the tunnel, and the data in Table 1 are obtained:

[0030] Table 1 Maximum pressure wave values under normal temperature and different heating section opening lengths

[0031]

[0032] Micro-pressure wave measurement points are set 20 m and 50 m away from the tunnel exit outside the tunnel, and the data in Table 2 are obtained:

[0033] Table 2 Maximum micro-pressure wave values under normal temperature and different heating section opening lengths

[0034]

[0035] As shown in Chart 1, it is the change of the pressure wave value when the heating zone length is related to the train body length. Table 2 is the change of the micro-pressure wave when the heating zone length is related to the streamlined length of the train head. It can be seen from the above table that when the opening length of the heating section is 1 times the train length or 1 times the streamlined length of the train head, the pressure wave value is the lowest under this set of conditions. A low pressure wave value indicates good mitigation of the aerodynamic effect. The content in Table 1 is used Figure 4 to show, Figure 4 In which point A represents that the opening length of the heating section is 0.5 times the train length, point B represents that the opening length of the heating section is 1 times the train length, and point C represents that the opening length of the heating section is 2 times the train length. Through Figure 4 the intuitive representation, it can be concluded that when the opening length of the heating section is the same as the train length or the streamlined length of the train head, the pressure wave mitigation rate is the highest and the aerodynamic mitigation effect is the best.

[0036] According to the above analysis, set the opening length of the heating section to be the same as the train body length, divide the tunnel length into 18 sections, and set a measurement point for each section:

[0037] Set up the heating zone starting from the tunnel entrance end as the first group of tests,

[0038] Set up the heating zone starting from the middle of the tunnel as the second group of tests,

[0039] Set up the heating zone starting from the tunnel exit end as the third group of tests,

[0040] Table 3 Data measured at each measurement point in the first group of tests

[0041]

[0042] As shown in Table 3, calculate the normal temperature pressure and heating pressure at each measurement point in the first group of tests, the second group of tests, and the third group of tests respectively, and then obtain the pressure wave mitigation rate at different positions of the tunnel in each group of tests, and obtain Figure 5 、 6 As shown in FIGS. 6 and 7, in the figures, the dimensionless length refers to the ratio of the distance from the measurement point in the tunnel to the tunnel entrance to the tunnel length;

[0043] According to Figure 5 、 6 、7, it can be seen that in the first group of tests, when the heating area is arranged starting from the tunnel entrance end, the pressure wave mitigation effect is the best. In the second group of tests, when the heating area is arranged starting from the middle of the tunnel, there is basically no mitigation effect on the pressure wave. In the third group of tests, when the heating area is arranged starting from the tunnel exit end, there is also a certain mitigation effect in some areas of the tunnel. Therefore, it can be concluded that the heating area needs to be arranged starting from the tunnel entrance end. If energy consumption is not considered, to achieve a better mitigation effect, the heating devices at both ends of the tunnel can be turned on simultaneously.

[0044] Example 2:

[0045] The tunnel is 5000 meters long, and 1 wind turbine is set every 5 meters on both sides of the tunnel, so a total of 2000 wind turbines can be set. When an 8-car train passes, the wind turbines can rotate for 10 s. Assuming the departure interval is 10 minutes, it can rotate for 60 s in 1 hour. When the optimized power generation efficiency of the wind turbine is 80% and its power is 2400 w, the power generation in one hour is 80 kWh.

[0046] Select the heating length to be 10 m of the streamline length. The energy required for the first heating is 200 kWh, and the energy required for each subsequent heating is 30 kWh. The total energy required is 350 kWh. Then it can provide 22.8% of the energy. Subsequently, by increasing the power and power generation efficiency of the generator, the self-sustainability of the system can be further achieved.

[0047] The above are only the preferred embodiments of the present invention, and do not limit the patent scope of the present invention accordingly. All equivalent structural transformations made under the concept of the present invention by using the content of the specification and drawings of the present invention, or directly / indirectly applied in other related technical fields are included in the patent protection scope of the present invention.

Claims

1. A tunnel aerodynamic effect mitigation device with a self-sustaining power supply system, characterized in that: Inside the tunnel, heating zones for heating the air inside the tunnel are respectively arranged starting from the tunnel openings at both ends of the tunnel. The heating zones inside the tunnel are divided into multiple continuously arranged heating segments along the length direction of the tunnel. Each heating segment can be individually controlled to open and close. Multiple wind power generation devices are also installed inside the tunnel and arranged in a row along the length direction of the tunnel. The wind power generation devices are connected to a storage battery through a control system. The storage battery supplies power to the heating zones through the control system. The multiple wind power generation devices are arranged at equal intervals and staggered on both sides of the track inside the tunnel. And one wind turbine is set every 5 meters on both sides of the tunnel. The power of the wind turbine is 2400w; Starting from the heating segment at the tunnel opening inside the tunnel, the total length of the continuously opened heating segments is the same as the streamlined length of the train head to pass through the tunnel or the same as the length of the train body. If it is necessary to relieve the micro-pressure wave outside the tunnel, a heating zone with the same length as the streamlined length of the train head is arranged inside the tunnel. If it is necessary to relieve both the pressure fluctuation inside the tunnel and the micro-pressure wave outside the tunnel at the same time, the length of the arranged heating zone is the same as the length of the train body; The heating zones at both ends of the tunnel are opened simultaneously; Heating devices are evenly arranged on each heating segment. A temperature monitoring system is installed inside the tunnel. Both the heating devices and the temperature monitoring system are connected to the control system. The temperature monitoring system monitors the temperature of the heating zones inside the tunnel in real time. The control system controls the opening and closing time of the heating devices according to the real-time arrival time of the train and the temperature required inside the tunnel.

2. The tunnel aerodynamic effect mitigation device with a self-sustaining power supply system according to claim 1, characterized in that: Before the train arrives at the tunnel, the heating segment heats the air inside the tunnel to 50°C - 100°C.

3. The tunnel aerodynamic effect mitigation device with a self-sustaining power supply system according to claim 2, characterized in that: The heating device is a heating sheet with a thickness not greater than 2mm, and the heating sheet is fixed on the inner wall of the tunnel.

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