Cross flow restraining method for longitudinal dirty air adjacent to tunnel

Abstract

The invention relates to the technical field of tunnel engineering, and provides a channeling inhibition method for longitudinal dirty air adjacent to a tunnel, which comprises the following steps: arranging a vertical blowing assembly at the bottom of an outlet of an upstream tunnel, and calculating the channeling of the dirty air when the dirty air is blown upwards from the outlet of the upstream tunnel through the vertical blowing assembly and just diffuses to the clear height of the tunnel; the method comprises the steps of calculating a first minimum air outlet speed of a vertical air blowing assembly, calculating a second minimum air outlet speed of the vertical air blowing assembly when dirty air discharged from an outlet of an upstream tunnel just diffuses to an inlet of a downstream tunnel, determining a critical air speed design value, and determining the total air supply amount of the vertical air blowing assembly according to the critical air speed design value. And a vertical air blowing assembly is arranged. According to the method, dirty air is prevented from channeling from the upstream tunnel to the downstream tunnel, the pollution load of the downstream tunnel is reduced, the driving environment of the downstream tunnel is ensured, the ventilation energy consumption of the downstream tunnel is not increased, the overall operation safety of the tunnel group is improved, and the method can be used for new projects and existing tunnels.

Description

Technical Field

[0001] The present invention relates to the technical field of tunnel engineering, and in particular to a method for suppressing the longitudinal cross-flow of polluted air in adjacent tunnels. Background Art

[0002] With the rapid development of China's highway transportation network, tunnel engineering is gradually extending towards complexity and intensification. In mountainous areas or urban underground spaces, due to terrain and planning restrictions, multiple tunnels are often arranged in parallel or staggered forms adjacent to each other. However, during the operation of such adjacent tunnels, due to the coupling of aerodynamic effects, the problem of cross-flow of polluted air between tunnels is likely to occur, that is, the polluted air (such as vehicle exhaust, dust, etc.) in one tunnel invades the adjacent downstream tunnel, seriously damaging the stability of the ventilation system. Traditional tunnel ventilation designs are mostly based on the independent operation mode of a single tunnel, without fully considering the aerodynamic coupling effect of multiple tunnels, resulting in out-of-control diffusion of polluted air and a sharp increase in ventilation energy consumption during actual operation, and even causing safety hazards such as a decrease in visibility.

[0003] Currently, the control technologies for cross-flow of polluted air have obvious limitations: Although the physical isolation measures (such as partitions, shed tunnels) in the existing technologies can block the lateral cross-flow paths between tunnels, they cannot control the longitudinal cross-flow of polluted air between adjacent tunnels; there is a lack of a systematic design method for the ventilation system of adjacent tunnel groups, and the critical cross-flow threshold and dynamic regulation mechanism are not clearly defined in the design standards, resulting in designers usually selecting a relatively large cross-flow threshold from a conservative perspective when facing the cross-flow of longitudinal polluted air, leading to an increase in ventilation energy consumption in the downstream tunnel.

[0004] In view of this, it is necessary to propose a method for suppressing the longitudinal cross-flow of polluted air in adjacent tunnels to solve or at least alleviate the above defects. Summary of the Invention

[0005] The main purpose of the present invention is to provide a method for suppressing the longitudinal cross-flow of polluted air in adjacent tunnels, so as to solve the technical problem that in the existing technology, there is a lack of a scheme for suppressing the longitudinal polluted air in adjacent tunnels, resulting in designers usually selecting a relatively large cross-flow threshold from a conservative perspective when facing the cross-flow of longitudinal polluted air, leading to an increase in ventilation energy consumption in the downstream tunnel.

[0006] To achieve the above object, the present invention provides a method for suppressing the longitudinal cross-flow of polluted air in adjacent tunnels, including the following steps: S1, arranging a vertical blowing component at the bottom of the outlet of the upstream tunnel; S2, calculating the first minimum air outlet speed of the vertical blowing component when the polluted air blown upward from the outlet of the upstream tunnel through the vertical blowing component just diffuses to the tunnel net height; S3, calculating the second minimum air outlet speed of the vertical blowing component when the polluted air discharged from the outlet of the upstream tunnel just diffuses to the entrance of the downstream tunnel; S4. Determine the larger value between the first minimum air outlet velocity and the second minimum air outlet velocity as the critical air velocity design value of the vertical air blowing component; S5. Determine the total air supply volume of the vertical air blowing component according to the critical air velocity design value, and then configure the vertical air blowing component according to the total air supply volume.

[0007] Preferably, the vertical air blowing component includes a fan and a main air duct. The main air duct is connected to the fan, the main air duct is connected to the outlet of the upstream tunnel and extends horizontally along the tunnel, and a plurality of strip-shaped air outlets are opened at the top of the main air duct.

[0008] Preferably, the step S2 specifically includes the following steps: Use the formula to calculate the first minimum air outlet velocity of the vertical air blowing component when the polluted air is blown upward through the vertical air blowing component from the outlet of the upstream tunnel and just diffuses to the tunnel net height. ; where is the width of the strip-shaped air outlet, is the empirical coefficient, is the tunnel net height, is the environmental air flow disturbance velocity threshold.

[0009] Preferably, the step S3 specifically includes the following steps: S31. Obtain the ventilation air flow velocity in the upstream tunnel, and the interval distance between the outlet of the upstream tunnel and the inlet of the downstream tunnel; S32. Calculate the minimum available time for the polluted air to diffuse from the outlet of the upstream tunnel to the inlet of the downstream tunnel according to the ventilation air flow velocity and the interval distance ; S33. Determine the second minimum air outlet velocity of the vertical air blowing component when the polluted air is blown upward through the vertical air blowing component from the outlet of the upstream tunnel and just diffuses to the tunnel net height according to the minimum available time .

[0010] Preferably, obtaining the ventilation air flow velocity in the upstream tunnel in the step S31 specifically includes the following steps: S311. Use the formula to calculate the required air volume for diluting the polluted air in the upstream tunnel; where is the polluted air emission volume in the upstream tunnel, is the standard atmospheric pressure, is the average summer temperature at the tunnel site, is the atmospheric pressure at the tunnel site, is the standard temperature; For S312, the formula is used to obtain the ventilation air flow velocity in the upstream tunnel ; where is the cross-sectional area of the upstream tunnel.

[0011] Preferably, the specific steps of determining the total air supply volume of the vertical blowing component according to the designed critical wind speed value in step S5 are as follows: Use to determine the total air supply volume of the vertical blowing component ; where is the designed critical wind speed value, is the number of strip-shaped air outlets, is the length of the strip-shaped air outlet.

[0012] Preferably, the following steps are further included after step S5: S51, obtain the average wind speed in the main air duct, and obtain the actual air supply volume of the vertical blowing component according to the average wind speed ; S52, according to the actual air supply volume obtain the actual air outlet speed of the strip-shaped air outlet ; S53, according to the actual air outlet speed obtain the actual maximum vertical distance that the polluted air is blown upward from the outlet of the upstream tunnel through the vertical blowing component , and then determine the vertical cross-flow coefficient of the polluted air according to the tunnel net height and the actual maximum vertical distance ; S54, according to the actual air outlet speed and the tunnel net height to obtain the actual available time of the polluted air , and then according to the actual available time and the ventilation air flow velocity obtain the actual horizontal movement distance of the polluted air , and then according to the actual horizontal movement distance of the polluted air obtain the horizontal cross-flow coefficient of the polluted air ; S55, according to the vertical cross-flow coefficient of the polluted air and the horizontal cross-flow coefficient of the polluted air obtain the comprehensive cross-flow coefficient of the polluted air ; S56, according to the comprehensive cross-flow coefficient of the polluted air determine the required air volume for diluting the cross-flow polluted air in the downstream tunnel ​, and then determine the number of additional fans required in the downstream tunnel according to the required air volume determine the number of additional fans required in the downstream tunnel .

[0013] Preferably, in step S54, according to the actual horizontal movement distance of the polluted air obtain the horizontal cross-flow coefficient of the polluted air Specifically, it includes the following steps: When the actual horizontal movement distance of the polluted air is greater than the interval distance , use the formula to obtain the horizontal cross-flow coefficient of the polluted air ; When the actual horizontal movement distance of the polluted air is less than or equal to the interval distance , the horizontal cross-flow coefficient of the polluted air is 1.

[0014] Preferably, step S55 specifically includes the following steps: Use the formula to obtain the comprehensive cross-flow coefficient of the polluted air .

[0015] Preferably, step S56 specifically includes the following steps: Use the formula to obtain the required air volume for diluting and cross-flowing the polluted air in the downstream tunnel ; Use the formula to obtain the number of additional fans required in the downstream tunnel ; where is the exhaust air volume of a single fan.

[0016] Compared with the prior art, the present invention has the following beneficial effects: The present invention provides a method for suppressing the cross-flow of longitudinal polluted air in adjacent tunnels. By setting a vertical blowing component at the bottom of the outlet of the upstream tunnel, calculating the first minimum air outlet speed of the vertical blowing component when the polluted air blown upward from the outlet of the upstream tunnel through the vertical blowing component just diffuses to the tunnel net height, calculating the second minimum air outlet speed of the vertical blowing component when the polluted air discharged from the outlet of the upstream tunnel just diffuses to the entrance of the downstream tunnel, determining the critical wind speed design value, determining the total air supply volume of the vertical blowing component according to the critical wind speed design value, and then configuring the vertical blowing component.

[0017] This application actively intervenes in the diffusion trajectory of polluted air, inhibits the flow of polluted air from the upstream tunnel to the downstream tunnel, reduces the pollution load of the downstream tunnel, ensures the driving environment of the downstream tunnel, and does not increase the ventilation energy consumption of the downstream tunnel. Instead of selecting a larger cross-flow threshold from a conservative perspective, which would increase the ventilation energy consumption of the downstream tunnel. In case of emergencies such as fires, inhibiting the cross-flow of polluted air can prevent the spread of harmful gases, provide a more favorable environment for personnel evacuation and rescue, and effectively improve the overall operational safety of the tunnel group. It can be used not only for new projects but also for existing tunnels. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for the description of the embodiments or the prior art. Obviously, the drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained based on the structures shown in these drawings.

[0019] Figure 1 It is a schematic flowchart of an embodiment of the present invention; Figure 2 It is a front view of the application scenario diagram of the vertical blowing component in an embodiment of the present invention; Figure 3 It is a top view of the application scenario diagram of the vertical blowing component in an embodiment of the present invention; Figure 4 It is a side view of the application scenario diagram of the vertical blowing component in an embodiment of the present invention.

[0020] The implementation, functional features, and advantages of the object of the present invention will be further described with reference to the embodiments and the drawings.

[0021] Explanation of the reference numerals in the drawings: 10. Upstream tunnel; 20. Downstream tunnel; 30. Vertical blowing component; 310. Fan; 320. Main air duct; 330. Strip-shaped air outlet; 340. Partition board; 410. Drain well; 420. Connecting pipe; 430. Overflow well; 50. Polluted air. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0022] It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0023] 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. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without making creative efforts shall fall within the protection scope of the present invention.

[0024] It should be noted that all directional indications (such as up, down, left, right, front, back...) in the embodiments of the present invention are only used to explain the relative position relationship and movement conditions between components in a specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indications will also change accordingly.

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

[0026] Please refer to the attached Figures 1 to 4 , a method for suppressing the cross-flow of longitudinal polluted air in adjacent tunnels provided by an embodiment of the present invention includes the following steps: S1. A vertical blowing component 30 is arranged at the bottom of the outlet of the upstream tunnel 10; S2. Calculate the first minimum air outlet speed of the vertical blowing component 30 when the polluted air 50 blows upward from the outlet of the upstream tunnel 10 through the vertical blowing component 30 and just diffuses to the tunnel net height; S3. Calculate the second minimum air outlet speed of the vertical blowing component 30 when the polluted air 50 discharged from the outlet of the upstream tunnel 10 just diffuses to the entrance of the downstream tunnel 20; S4. Determine the larger value of the first minimum air outlet speed and the second minimum air outlet speed as the critical air speed design value of the vertical blowing component 30; S5. Determine the total air supply volume of the vertical blowing component 30 according to the critical air speed design value, and then configure the vertical blowing component 30 according to the total air supply volume.

[0027] Specifically, as Figure 2 shown, the small arrows in the figure are the air flow directions of the fans 310. A vertical blowing component 30 is arranged at the bottom of the outlet of the upstream tunnel 10, and an upward blowing force is applied to the polluted air 50 discharged from the outlet of the upstream tunnel 10 to change the diffusion trajectory of its free jet. The ultimate goal is to blow the tunnel polluted air 50 above the tunnel net height by means of the vertical blowing component 30 to suppress the cross-flow of the polluted air 50 from the upstream tunnel 10 to the downstream tunnel 20.

[0028] By taking the larger value between the first minimum air outlet speed and the second minimum air outlet speed as the design value of the critical wind speed, it is ensured that in the theoretical design scenario, the dirty air 50 can be effectively inhibited from flowing into the downstream tunnel 20. Then, based on the design value of the critical wind speed, the total air supply volume of the vertical air blowing component 30 is determined, and the vertical air blowing component 30 is configured according to the total air supply volume.

[0029] In the solution of this application, by actively intervening in the diffusion trajectory of the dirty air 50, the dirty air 50 is inhibited from flowing into the downstream tunnel 20 from the upstream tunnel 10, the pollution load of the downstream tunnel 20 is reduced, the driving environment of the downstream tunnel 20 is ensured, and the ventilation energy consumption of the downstream tunnel 20 is not increased, rather than selecting a larger cross-flow threshold from a conservative perspective, resulting in an increase in the ventilation energy consumption of the downstream tunnel 20. In case of emergencies such as fires, inhibiting the cross-flow of the dirty air 50 can prevent the spread of harmful gases and provide a more favorable environment for personnel evacuation and rescue, effectively improving the overall operation safety of the tunnel group. It can be used not only for new projects but also for existing tunnels.

[0030] Preferably, the vertical air blowing component 30 includes a fan 310 and a main air duct 320. The main air duct 320 is communicated with the fan 310. The main air duct 320 is connected to the outlet of the upstream tunnel 10 and extends along the transverse direction of the tunnel. A plurality of strip-shaped air outlets 330 are opened at the top of the main air duct 320.

[0031] As Figure 2 shown, as a preferred example, axial fans 310 are respectively arranged on the left and right sides of the main air duct 320 to supply air to the main air duct 320, so that a positive pressure is formed inside the main air duct 320. A plurality of strip-shaped air outlets 330 are opened at the top of the main air duct 320. Further, a partition plate 340 can be arranged in the middle of the main air duct 320 to divide the main air duct 320 into two independent areas on the left and right, and each side fan 310 supplies air. Preferably, the cross-sectional size of the main air duct 320 is 80 cm × 100 cm. The main air duct 320 is made of reinforced concrete structure, and the inner wall is leveled with C30 cement to reduce the wind resistance coefficient. Further, soft connections are adopted between the left and right ends of the main air duct 320 and the fan 310 to eliminate the influence of the vibration of the fan 310 on the tunnel entrance and the road surface structure.

[0032] Furthermore, considering that the vertical air blowing component 30 is located in an outdoor environment (connected to the outlet position of the upstream tunnel 10) and the strip-shaped air outlets 330 are external outlets, a drainage system is specifically designed in this embodiment, such as Figure 2As shown in the figure, the small arrow in the figure indicates the air flow direction of the fan 310. The drainage system is arranged below the main air duct 320. The drainage system includes a drainage well 410, a connecting pipe 420, and an overflow well 430. The upper end of the drainage well 410 is connected to the main air duct 320. The connecting pipe 420 is used to connect the drainage well 410 and the overflow well 430. Preferably, the size of the drainage well 410 is 50×50×80 cm, and the size of the overflow well 430 is 100×100×100 cm. The drainage well 410 and the overflow well 430 are concrete pools. Preferably, the top surface of the overflow well 430 is 30 cm higher than the ground of the drainage well 410 to meet the water seal requirement. The pool size can be adjusted according to the actual situation.

[0033] As a preferred embodiment, step S2 specifically includes the following steps: Using the formula Calculate the first minimum air outlet velocity of the vertical air blowing assembly 30 when the polluted air 50 is blown upward from the outlet of the upstream tunnel 10 through the vertical air blowing assembly 30 and just diffuses to the tunnel net height , unit: , where is the width of the strip-shaped air outlet 330, unit: m, is the empirical coefficient, is the tunnel net height, unit: m, is the environmental air flow disturbance velocity threshold, unit: .

[0034] Those skilled in the art can understand that according to the free jet theory and fluid mechanics, after the air flow in the main air duct 320 is ejected from the strip-shaped air outlet 330, there will be two development stages: ① There is a core stable area near the strip-shaped air outlet 330, where the flow velocity basically remains unchanged.

[0035] For an air outlet close to a square (for example, the length of the strip-shaped air outlet 330 / the width of the strip-shaped air outlet 330 is less than 5), the core area is close to the law of circular jet, and the length is about 4-6 times the width , and the intermediate value of 5 times can be taken; Core area length = 5× = 5×0.0375 = 0.1875 m Formula (1) ② There is a velocity decay area outside the core stable area: Outside the core area (distance x > 0.1875 m), the air flow velocity decays according to the three-dimensional jet model, and the formula is: Formula (2) Where For height The corresponding air flow velocity is is an empirical coefficient. As a preferred example, the length-to-width ratio of the strip air outlet 330 is: / =0.1 / 0.0375=2.67:1, which belongs to a rectangular jet with a low aspect ratio. Its three-dimensional jet characteristics are consistent with those of a circular jet, so the empirical coefficient Take 0.16, which is consistent with the circular jet. =0.16); When the airflow velocity decays to the ambient airflow disturbance velocity threshold, preferably, the ambient airflow disturbance velocity threshold The theoretical maximum distance for: Formula (3) Usually, in It is greater than or equal to the clear height of the tunnel, that is, the dirty wind 50 diffuses out from the top of the tunnel and no longer flows into the downstream tunnel 20, thereby achieving the longitudinal suppression of the dirty wind 50.

[0036] Formula (4) Therefore, , Substituting formula (3) and formula (4) together, we can get , from which the first minimum air outlet velocity of the strip air outlet 330 can be calculated .

[0037] The first minimum air outlet speed calculated in this embodiment Taking into full consideration the law of upward airflow, the first minimum air outlet speed It can not only ensure that the polluted air 50 is blown upward to the clear height of the tunnel, but also reduce the energy consumption of the fan 310 to the greatest extent.

[0038] As a preferred implementation, step S3 specifically includes the following steps: S31, obtaining the ventilation air flow speed in the upstream tunnel 10 , and the spacing distance between the exit of the upstream tunnel 10 and the entrance of the downstream tunnel 20 ; S32, according to the ventilation air flow speed and the spacing distance Calculate the minimum available time for the polluted air 50 to diffuse from the exit of the upstream tunnel 10 to the entrance of the downstream tunnel 20 ; S33, according to the minimum available time Determine the second minimum air outlet velocity of the vertical air blowing assembly 30 when the polluted air 50 is blown upward from the outlet of the upstream tunnel 10 through the vertical air blowing assembly 30 and just diffuses to the tunnel's net height .

[0039] It should be noted that generally, the air flow in the tunnel (polluted air 50) has a ventilation air flow velocity After being discharged from the tunnel, there are also a core stable area and a velocity decay area. That is, after diffusing a certain distance, it will stop diffusing downstream. However, if there are vehicles moving between the upstream tunnel 10 and the downstream tunnel 20, these vehicles will slowly drive the stationary polluted air 50 to continue diffusing into the downstream tunnel 20. Therefore, calculating the diffusion distance of the polluted air 50 using the traditional jet model is too risky.

[0040] In this embodiment, starting from improving the tunnel safety resilience, the horizontal movement of the polluted air 50 is assumed to be a uniform motion at the ventilation air flow velocity , and then the extreme situation of the polluted air 50 cross-flow is simulated. The final result obtained by considering the most unfavorable situation can meet the requirements of the tunnel safety resilience.

[0041] Specifically, first calculate the movement distance of the polluted air 50 from the outlet of the upstream tunnel 10 towards the downstream tunnel 20 : Formula (5) ① Calculate the movement time of the polluted air 50 air flow (the movement time in each direction is equal): The movement speed of the polluted air 50 is a function of the movement distance , and , so there is: Formula (6) Separate variables and integrate: Formula (7) Initial conditions , (the length of the core area is relatively small and can be ignored). Combining the above formulas, the movement time of the polluted air 50 air flow can be calculated , when , the corresponding movement time of the polluted air 50 air flow is , that is, the time required for the polluted air 50 to move from the ground at the tunnel outlet to the tunnel top (defined as the available time for the horizontal movement of the polluted air 50).

[0042] ② Calculate the tunnel ventilation air flow velocity To dilute the polluted air such as CO in the tunnel 50, a fan 310 needs to be installed in the tunnel to form a ventilation air flow. The ventilation air velocity in the tunnel needs to be determined comprehensively according to the CO emission, pressure, temperature, tunnel size, etc. in the tunnel. The calculation formula is as follows: Formula (8) Formula (9) Generally, it is desired that be less than or equal to the tunnel spacing , that is, within the available time for the horizontal movement of the polluted air 50, the polluted air 50 discharged from the upstream tunnel 10 does not spread to the downstream tunnel 20.

[0043] Formula (10) In summary, the minimum available time for the polluted air 50 to spread from the outlet of the upstream tunnel 10 to the inlet of the downstream tunnel 20 can be calculated . When the minimum available time is less than the vertical available time , then , , are substituted into Formula (7), and the second minimum air outlet velocity of the vertical air blowing component 30 can be calculated .

[0044] The second minimum air outlet velocity calculated in this embodiment fully considers the law of the horizontal jet of the air flow. The second minimum air outlet velocity can not only ensure that the polluted air 50 is not blown to the downstream tunnel 20, but also reduce the energy consumption of the fan 310 to the greatest extent.

[0045] Further, obtaining the ventilation air velocity in the upstream tunnel 10 in step S31 specifically includes the following steps: S311, use the formula to calculate the required air volume for diluting the polluted air 50 in the upstream tunnel 10 , unit: m 3 / s; where is the emission of the polluted air 50 in the upstream tunnel 10, unit: m 3 / s, is the standard atmospheric pressure, unit: kN / m 2 , take 101.325 kN / m 2 , is the average summer temperature at the tunnel site, unit: K, is the atmospheric pressure at the tunnel site, unit: kN / m 2 , and the local average atmospheric pressure can be taken, is the standard temperature, unit: K; S312, using the formula to obtain the ventilation air flow velocity in the upstream tunnel 10 ; where is the cross-sectional area of the upstream tunnel 10, unit: m 2 .

[0046] Furthermore, the specific steps of determining the total air supply volume of the vertical blowing component 30 according to the designed critical wind speed value in the step S5 are as follows: Using to determine the total air supply volume of the vertical blowing component 30 ; where is the designed critical wind speed value, unit: , is the number of strip air outlets 330, unit: piece, is the length of the strip air outlet 330, unit: m.

[0047] As another preferred embodiment, the steps after the step S5 further include the following steps: S51, obtaining the average wind speed in the main air duct 320, and obtaining the actual air supply volume of the vertical blowing component 30 according to the average wind speed ; S52, according to the actual air supply volume to obtain the actual air outlet speed of the strip air outlet 330 ; S53, according to the actual air outlet speed to obtain the actual maximum vertical distance that the polluted air 50 is blown upward from the outlet of the upstream tunnel 10 through the vertical blowing component 30 , and then determining the vertical cross-flow coefficient of the polluted air 50 according to the tunnel net height and the actual maximum vertical distance ; ; S54, obtaining the actual available time of the polluted air 50 according to the actual air outlet speed and the tunnel net height, and then obtaining the actual horizontal movement distance of the polluted air 50 according to the actual available time and the ventilation air flow velocity , and then obtaining the horizontal cross-flow coefficient of the polluted air 50 according to the actual horizontal movement distance of the polluted air 50 ; ; ; S55, obtaining the comprehensive cross-flow coefficient of the polluted air 50 according to the vertical cross-flow coefficient of the polluted air 50 and the horizontal cross-flow coefficient of the polluted air 50 ; S56. Determine the required air volume for diluting the cross-flow contaminated air 50 in the downstream tunnel 20 according to the comprehensive cross-flow coefficient of the contaminated air 50 and then determine the number of additional fans 310 required in the downstream tunnel 20 according to the required air volume . .

[0048] It should be noted that during the actual operation of the tunnel, there may be situations where the actual air supply volume of the fan 310 designed in the foregoing embodiments cannot meet the design requirements due to fluctuations in the power system, device failures, etc. At this time, the downstream tunnel 20 needs to further adjust the number of ventilation fans 310 started in the downstream tunnel 20 according to the cross-flow situation to ensure the driving environment in the downstream tunnel 20.

[0049] Specifically, in this embodiment, by obtaining the average wind speed in the main air duct 320, the actual air supply volume of the vertical blowing component 30 is obtained according to the average wind speed . Preferably, a plurality of wind speed detection points can be arranged in the main air duct 320, and the average value of the wind speeds obtained at the plurality of detection points is used as the average wind speed. Then, according to the actual air supply volume , the actual air outlet speed of the strip-shaped air outlet 330 is obtained . Specifically, the formula can be used: to obtain; then, substituting the actual air outlet speed into formula (2), the actual maximum vertical distance that the contaminated air 50 is blown upward from the outlet of the upstream tunnel 10 through the vertical blowing component 30 can be obtained ; The vertical cross-flow coefficient of the contaminated air 50 can be obtained by using the formula ; then, substituting the actual air outlet speed and into formula (7), the actual available time of the contaminated air 50 is calculated : Furthermore, in step S54, obtaining the horizontal cross-flow coefficient of the actual contaminated air 50 according to the actual horizontal movement distance of the contaminated air 50 specifically includes the following steps: When the actual horizontal movement distance of the contaminated air 50 is greater than the interval distance , the horizontal cross-flow coefficient of the contaminated air 50 is obtained by using the formula : ; When the actual horizontal movement distance of the contaminated air 50 is less than or equal to the interval distance , the horizontal cross-flow coefficient of the contaminated air 50 is 1 . ​​

[0050] Further, the step S55 specifically includes the following steps: Using the formula to obtain the comprehensive cross-flow coefficient of the polluted air 50 .

[0051] Further, the step S56 specifically includes the following steps: Using the formula to obtain the required air volume for diluting and cross-flowing the polluted air 50 in the downstream tunnel 20 ; Using the formula to obtain the number of additional fans 310 required for the downstream tunnel 20 ; where is the exhaust air volume of a single fan 310.

[0052] In this embodiment, a targeted design is carried out for this special working condition to achieve dynamic regulation according to the actual average wind speed in the main air duct 320, which can not only effectively improve the ventilation environment in the downstream tunnel 20, but also minimize energy consumption to avoid blind selection.

[0053] The above are only the preferred embodiments of the present invention, and do not limit the protection scope of the present invention accordingly. Any equivalent structure or equivalent process transformation made by using the content of the specification and drawings of the present invention, or directly or indirectly applied in other related technical fields, shall be equally included in the protection scope of the present invention.

Claims

1. A method for suppressing the cross-flow of longitudinal polluted air in adjacent tunnels, characterized in that, It includes the following steps: S1. A vertical air blowing assembly is arranged at the bottom of the outlet of the upstream tunnel. S2. Calculate the first minimum air outlet speed of the vertical air blowing assembly when the polluted air blown upward by the vertical air blowing assembly from the outlet of the upstream tunnel just diffuses to the net height of the tunnel. S3. Calculate the second minimum air outlet speed of the vertical air blowing assembly when the polluted air discharged from the outlet of the upstream tunnel just diffuses to the inlet of the downstream tunnel. S4. Determine the larger value between the first minimum air outlet speed and the second minimum air outlet speed as the critical air speed design value of the vertical air blowing assembly. S5. Determine the total air supply volume of the vertical air blowing assembly according to the critical air speed design value, and then configure the vertical air blowing assembly according to the total air supply volume.

2. The method for suppressing the longitudinal cross-flow of polluted air in adjacent tunnels according to claim 1, wherein The vertical air blowing assembly includes a fan and a main air duct. The main air duct is communicated with the fan. The main air duct is connected to the outlet of the upstream tunnel and extends horizontally along the tunnel. A plurality of strip-shaped air outlets are arranged at the top of the main air duct.

3. The longitudinal cross-flow suppression method for the contaminated air adjacent to the tunnel according to claim 2, characterized in that, The specific steps of step S2 include the following steps: Using the formula calculate the first minimum air outlet velocity of the vertical air blowing component when the polluted air is blown upward from the outlet of the upstream tunnel through the vertical air blowing component and just diffuses to the tunnel's net height ; where is the width of the strip-shaped air outlet is the empirical coefficient is the tunnel's net height is the threshold value of the environmental air flow disturbance velocity 4. The method for suppressing the cross-flow of longitudinal polluted air in adjacent tunnels according to claim 2, characterized in that, The specific steps of step S3 include the following steps: S31, obtain the ventilation airflow velocity in the upstream tunnel , and the interval distance between the outlet of the upstream tunnel and the inlet of the downstream tunnel ; S32, according to the ventilation air flow velocity and the interval distance calculate the minimum available time for the polluted air to spread from the outlet of the upstream tunnel to the inlet of the downstream tunnel ; S33, according to the minimum available time Determine the second minimum air outlet velocity of the vertical air blowing assembly when the polluted air is blown upward from the outlet of the upstream tunnel through the vertical air blowing assembly and just diffuses to the tunnel net height .

5. The method for suppressing the longitudinal cross-flow of polluted air in adjacent tunnels according to claim 4, characterized in that, Obtaining the ventilation air flow velocity in the upstream tunnel in step S31 Specifically, it includes the following steps: S311, use the formula to calculate the required air volume for diluting the polluted air in the upstream tunnel ; where is the emission of polluted air in the upstream tunnel, is the standard atmospheric pressure, is the average summer temperature at the tunnel site, is the atmospheric pressure at the tunnel site, is the standard temperature. S312, using the formula to obtain the ventilation airflow velocity in the upstream tunnel ; where is the cross-sectional area of the upstream tunnel.

6. The longitudinal cross-flow suppression method for polluted air in adjacent tunnels according to claim 3, characterized in that, The specific steps of determining the total air supply volume of the vertical air blowing assembly according to the critical air speed design value in step S5 include the following steps: Adopt Determine the total air supply volume of the vertical air blowing assembly ; wherein is the design value of the critical wind speed is the number of strip-shaped air outlets is the length of the strip-shaped air outlet 7. The method for suppressing the longitudinal cross-flow of polluted air in adjacent tunnels according to claim 5, characterized in that, After step S5, the following steps are further included: S51. Obtain the average wind speed in the main air duct, and obtain the actual air supply volume of the vertical air blowing component according to the average wind speed ; S52, according to the actual air supply volume obtain the actual air outlet speed of the strip-shaped air outlet ; S53, according to the actual air outlet speed obtain the actual maximum vertical distance that the polluted air is blown upward by the vertical air blowing component from the outlet of the upstream tunnel , and then according to the tunnel net height and the actual maximum vertical distance determine the vertical cross-flow coefficient of the polluted air ; S54, according to the actual air outlet speed and the net height of the tunnel to obtain the actual available time of the polluted air , and then according to the actual available time and the ventilation air flow speed to obtain the actual horizontal movement distance of the polluted air , and then according to the actual horizontal movement distance of the polluted air to obtain the horizontal cross-flow coefficient of the polluted air ; S55, according to the vertical cross-flow coefficient of contaminated air and the horizontal cross-flow coefficient of contaminated air to obtain the comprehensive cross-flow coefficient of contaminated air ; S56, according to the comprehensive cross-flow coefficient of polluted air Determine the required air volume for diluting and cross-flowing polluted air in the downstream tunnel , and then according to the required air volume Determine the number of additional fans required for the downstream tunnel .

8. The longitudinal cross-flow suppression method for adjacent tunnels as claimed in claim 7, wherein In step S54, according to the actual horizontal movement distance of the contaminated air the horizontal cross-flow coefficient of the contaminated air is obtained Specifically, it includes the following steps: At the actual horizontal movement distance of the polluted air greater than the interval distance when, use the formula to obtain the horizontal cross-flow coefficient of the polluted air ; At the actual horizontal movement distance of the polluted air Less than or equal to the interval distance The horizontal cross-flow coefficient of the polluted air Is 1 9. The longitudinal cross-flow suppression method for contaminated air in adjacent tunnels according to claim 7, characterized in that, The specific steps of step S55 include the following steps: Using the formula the comprehensive cross-flow coefficient of the polluted air is obtained .

10. The method for suppressing the cross-flow of longitudinal polluted air in adjacent tunnels according to claim 7, characterized in that, The specific steps of step S56 include the following steps: Using the formula to obtain the required air volume for diluting the cross-flow polluted air in the downstream tunnel ; Using the formula to obtain the number of additional fans required for the downstream tunnel ; where is the exhaust air volume of a single fan.

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