A method for suppressing longitudinal dirty air flow in continuous tunnels

Abstract

The present invention relates to the field of tunnel engineering technology, and provides a method for suppressing the crossflow of longitudinal polluted air in a continuous tunnel. The method comprises the following steps: arranging a vertical blowing assembly at the bottom of the outlet of an upstream tunnel, calculating the first minimum air outlet velocity of the vertical blowing assembly when the polluted air is blown upward from the outlet of the upstream tunnel through the vertical blowing assembly and just diffused to the clear height of the tunnel, calculating the second minimum air outlet velocity of the vertical blowing assembly when the polluted air discharged from the outlet of the upstream tunnel just diffused to the entrance of the downstream tunnel, determining a critical air velocity design value, determining the total air supply volume of the vertical blowing assembly based on the critical air velocity design value, and then configuring the vertical blowing assembly. The present application suppresses the crossflow 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, does not increase the ventilation energy consumption of the downstream tunnel, and improves the overall operational safety of the tunnel group. The method can be used not only for new projects but also for existing tunnels.

Description

Technical Field

[0001] The invention relates to the technical field of tunnel engineering, in particular to a method for suppressing longitudinal dirty air channeling in a continuous tunnel. Background Art

[0002] With the rapid development of my country's highway transportation network, tunnel engineering is becoming increasingly complex and dense. In mountainous areas or urban underground spaces, due to topographical and planning constraints, multiple tunnels are often arranged in parallel or staggered configurations adjacent to each other. However, during operation, these adjacent tunnels are susceptible to inter-tunnel contamination due to aerodynamic coupling. This occurs when polluted air (such as vehicle exhaust and dust) from one tunnel intrudes into the downstream adjacent tunnel, seriously undermining the stability of the ventilation system. Traditional tunnel ventilation designs are often based on the independent operation of a single tunnel, failing to fully consider the aerodynamic coupling effects of multiple tunnels. This can lead to uncontrolled contamination diffusion, a dramatic increase in ventilation energy consumption, and even safety hazards such as reduced visibility.

[0003] Current technologies for controlling dirty air crossflow have significant limitations: while existing physical isolation measures (such as partitions and tunnels) can block lateral crossflow paths between tunnels, they cannot control longitudinal crossflow between adjacent tunnels. There is a lack of systematic design methods for continuous tunnel ventilation systems, and the design standards do not clearly define the critical crossflow threshold and dynamic control mechanism. As a result, when faced with longitudinal crossflow, designers usually conservatively select a larger crossflow threshold, resulting in increased ventilation energy consumption in downstream tunnels.

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

[0005] The main purpose of the present invention is to provide a method for suppressing the crossflow of longitudinal dirty air in a continuous tunnel, so as to solve the technical problem that the existing technology lacks a solution for suppressing longitudinal dirty air in adjacent tunnels, resulting in designers usually selecting a larger crossflow threshold from a conservative perspective when facing the crossflow of longitudinal dirty air, which leads to increased ventilation energy consumption in downstream tunnels.

[0006] To achieve the above object, the present invention provides a method for suppressing longitudinal dirty air flow in a continuous tunnel, comprising the following steps:

[0007] S1, a vertical blowing assembly is set at the bottom of the exit of the upstream tunnel;

[0008] S2, calculating the first minimum air outlet velocity of the vertical blowing assembly when the polluted air is blown upward from the outlet of the upstream tunnel through the vertical blowing assembly and diffuses to the clear height of the tunnel;

[0009] S3, calculating the second minimum air outlet speed of the vertical blowing assembly when the polluted air discharged from the outlet of the upstream tunnel just diffuses to the entrance of the downstream tunnel;

[0010] S4, determining the larger value of the first minimum air outlet speed and the second minimum air outlet speed as the critical wind speed design value of the vertical blowing component;

[0011] S5, determining the total air supply volume of the vertical blowing assembly according to the critical wind speed design value, and then configuring the vertical blowing assembly according to the total air supply volume.

[0012] Preferably, the vertical blowing assembly 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 air outlets are opened on the top of the main air duct.

[0013] Preferably, step S2 specifically includes the following steps:

[0014] Using the formula Calculate the first minimum air outlet speed of the vertical blowing assembly when the polluted air is blown upward from the outlet of the upstream tunnel through the vertical blowing assembly and just diffused to the clear height of the tunnel. ;in, is the width of the strip air outlet, is the empirical coefficient, is the clear height of the tunnel, is the ambient air flow disturbance velocity threshold.

[0015] Preferably, the step S3 specifically includes the following steps:

[0016] S31, obtain the ventilation air velocity in the upstream tunnel , and the separation distance between the exit of the upstream tunnel and the entrance of the downstream tunnel ;

[0017] S32, according to the ventilation air flow speed and the separation distance Calculate the minimum available time for polluted air to diffuse from the exit of the upstream tunnel to the entrance of the downstream tunnel ;

[0018] S33, according to the minimum available time Determine the second minimum air outlet speed of the vertical blowing assembly when the polluted air is blown upward from the outlet of the upstream tunnel through the vertical blowing assembly and just diffuses to the clear height of the tunnel .

[0019] Preferably, the ventilation air velocity in the upstream tunnel is obtained in step S31. The specific steps include:

[0020] S311, using formula Calculate the air volume required to dilute the polluted air in the upstream tunnel ;in, is the amount of polluted air discharged from the upstream tunnel, is standard atmospheric pressure, is the average summer temperature at the tunnel site, is the atmospheric pressure at the tunnel site, is the standard temperature;

[0021] S312, using formula Get the ventilation air velocity in the upstream tunnel ;in, is the cross-sectional area of ​​the upstream tunnel.

[0022] Preferably, determining the total air supply volume of the vertical blowing assembly according to the critical wind speed design value in step S5 specifically includes the following steps:

[0023] use Determine the total air supply volume of the vertical blowing assembly ;in, is the critical wind speed design value, is the number of strip air outlets, is the length of the strip air outlet.

[0024] Preferably, the step S5 further includes the following steps:

[0025] S51, obtaining the average wind speed in the main air duct, and obtaining the actual air supply volume of the vertical blowing component based on the average wind speed ;

[0026] S52, according to the actual air supply volume Get the actual air outlet speed of the strip air outlet ;

[0027] 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 assembly , and then according to the tunnel clear height and the actual maximum vertical distance Determine the vertical crossflow coefficient of dirty air ;

[0028] S54, according to the actual air speed The actual available time of the polluted air is obtained by using the clear height of the tunnel , and then based on the actual available time and ventilation air flow speed Get the actual horizontal movement distance of the polluted air , and then according to the actual horizontal movement distance of the polluted air Get the horizontal crossflow coefficient of dirty air ;

[0029] S55, based on the vertical crossflow coefficient of polluted air Horizontal crossflow coefficient of polluted air Get the comprehensive crossflow coefficient of dirty air ;

[0030] S56, based on the comprehensive crossflow coefficient of polluted air Determine the required air volume for dilution and cross-flow of polluted air in the downstream tunnel , and then according to the required air volume Determine the number of fans required in the downstream tunnel .

[0031] Preferably, in step S54, the actual horizontal movement distance of the polluted air is Get the horizontal crossflow coefficient of dirty air The specific steps include:

[0032] In actual horizontal movement distance of polluted air Greater than the separation distance When using the formula Get the horizontal crossflow coefficient of dirty air ;

[0033] In actual horizontal movement distance of polluted air Less than or equal to the separation distance When the horizontal crossflow coefficient of dirty air is is 1.

[0034] Preferably, the step S55 specifically includes the following steps:

[0035] Using the formula Get the comprehensive crossflow coefficient of dirty air .

[0036] Preferably, the step S56 specifically includes the following steps:

[0037] Using the formula Obtain the required air volume for dilution and crossflow of polluted air in the downstream tunnel ;

[0038] Using the formula Get the number of fans that need to be added in the downstream tunnel ;in, The exhaust volume of a single fan.

[0039] Compared with the prior art, the present invention has the following beneficial effects:

[0040] The present invention provides a method for suppressing the crossflow of longitudinal polluted air in a continuous tunnel. The method comprises the following steps: arranging a vertical blowing assembly at the bottom of the outlet of an upstream tunnel, calculating a first minimum air outlet velocity of the vertical blowing assembly when the polluted air is blown upward from the outlet of the upstream tunnel through the vertical blowing assembly and just diffused to the net height of the tunnel, calculating a second minimum air outlet velocity of the vertical blowing assembly when the polluted air discharged from the outlet of the upstream tunnel just diffused to the entrance of a downstream tunnel, determining a critical wind speed design value, determining a total air supply volume of the vertical blowing assembly based on the critical wind speed design value, and then configuring the vertical blowing assembly.

[0041] This application proactively intervenes in the diffusion trajectory of polluted air, suppressing its flow from upstream tunnels to downstream tunnels, reducing the pollution load in downstream tunnels and ensuring a safe driving environment. This approach does not increase ventilation energy consumption in downstream tunnels, rather than conservatively selecting a larger crossflow threshold that would increase ventilation energy consumption in downstream tunnels. In emergencies such as fires, suppressing the crossflow of polluted air prevents the spread of harmful gases, creating a more favorable environment for evacuation and rescue, and effectively improving the overall operational safety of the tunnel cluster. This approach is applicable not only to new projects but also to existing tunnels. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the structures shown in these drawings without paying any creative work.

[0043] Figure 1 is a schematic diagram of a flow chart in one embodiment of the present invention;

[0044] Figure 2 This is a front view of an application scenario diagram of a vertical blowing assembly in one embodiment of the present invention;

[0045] Figure 3 This is a top view of an application scenario diagram of a vertical blowing assembly in one embodiment of the present invention;

[0046] Figure 4 This is a side view of an application scenario diagram of a vertical blowing assembly in one embodiment of the present invention.

[0047] The purpose, features and advantages of the present invention will be further described with reference to the accompanying drawings and in conjunction with the embodiments.

[0048] Description of Figure Numbers:

[0049] 10. Upstream tunnel; 20. Downstream tunnel; 30. Vertical blowing assembly; 310. Fan; 320. Main air duct; 330. Strip air outlet; 340. Partition plate; 410. Drainage well; 420. Connecting pipe; 430. Overflow well; 50. Dirty air. DETAILED DESCRIPTION

[0050] It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0051] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. All other embodiments obtained by ordinary technicians in this field based on the embodiments of the present invention without making any creative efforts shall fall within the scope of protection of the present invention.

[0052] It should be noted that all directional indications (such as up, down, left, right, front, back, etc.) in the embodiments of the present invention are only used to explain the relative position relationship, movement status, etc. between the various components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication will also change accordingly.

[0053] In addition, the technical solutions between the various embodiments can be combined with each other, but they must be based on the fact that ordinary technicians in this field can implement them. When the combination of technical solutions is mutually contradictory or cannot be implemented, it should be deemed that such a combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

[0054] Please see the attached Figures 1 to 4 In one embodiment of the present invention, a method for suppressing longitudinal dirty air flow in a continuous tunnel includes the following steps:

[0055] S1, a vertical blowing assembly 30 is provided at the bottom of the exit of the upstream tunnel 10;

[0056] S2, calculating a first minimum outlet velocity of the vertical blowing assembly 30 when the polluted air 50 is blown upward from the outlet of the upstream tunnel 10 through the vertical blowing assembly 30 and diffuses to the clear height of the tunnel;

[0057] S3, calculating the second minimum air outlet velocity of the vertical blowing assembly 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;

[0058] S4, determining the larger value of the first minimum air outlet speed and the second minimum air outlet speed as the critical wind speed design value of the vertical blowing assembly 30;

[0059] S5, determining the total air supply volume of the vertical blowing assembly 30 according to the critical wind speed design value, and then configuring the vertical blowing assembly 30 according to the total air supply volume.

[0060] Specifically, such as Figure 2 As shown in the figure, the small arrow is the airflow direction of the fan 310. A vertical blowing assembly 30 is set at the bottom of the upstream tunnel 10 outlet. By applying an upward blowing force to the polluted air 50 discharged from the upstream tunnel 10 outlet, the diffusion trajectory of its free jet is changed. The ultimate goal is to use the vertical blowing assembly 30 to blow the tunnel polluted air 50 to above the tunnel clear height, thereby suppressing the polluted air 50 from flowing from the upstream tunnel 10 to the downstream tunnel 20.

[0061] By taking the larger value of the first minimum air outlet speed and the second minimum air outlet speed as the critical wind speed design value, it is ensured that under theoretical design conditions, the dirty air 50 can be effectively suppressed from flowing into the downstream tunnel 20, and then the total air supply volume of the vertical blowing assembly 30 is determined according to the critical wind speed design value, and then the vertical blowing assembly 30 is configured according to the total air supply volume.

[0062] In this application, by actively intervening in the diffusion trajectory of polluted air 50, the polluted air 50 is suppressed from flowing from upstream tunnel 10 to downstream tunnel 20, reducing the pollution load in downstream tunnel 20 and ensuring a safe driving environment in downstream tunnel 20 without increasing ventilation energy consumption in downstream tunnel 20. This approach, rather than conservatively selecting a larger crossflow threshold that would increase ventilation energy consumption in downstream tunnel 20, prevents the spread of harmful gases in emergencies such as fires, creating a more favorable environment for evacuation and rescue, and effectively improving the overall operational safety of the tunnel cluster. This approach is applicable not only to new projects but also to existing tunnels.

[0063] Preferably, the vertical blowing assembly 30 includes a fan 310 and a main air duct 320, the main air duct 320 is connected to the fan 310, the main air duct 320 is connected to the outlet of the upstream tunnel 10 and extends horizontally along the tunnel, and a plurality of strip-shaped air outlets 330 are opened at the top of the main air duct 320.

[0064] like Figure 2As shown, as a preferred example, axial flow fans 310 are respectively provided 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 provided on the top of the main air duct 320, and a partition plate 340 can be further provided 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, which are supplied with air by the fans 310 on each side. Preferably, the cross-sectional dimensions of the main air duct 320 are 80cm×100cm, and the main air duct 320 adopts a reinforced concrete structure, and the inner wall is leveled with C30 cement to reduce the wind resistance coefficient. Furthermore, soft connections are used between the left and right ends of the main air duct 320 and the fans 310 to eliminate the impact of the vibration of the fans 310 on the tunnel entrance and the road surface structure.

[0065] Furthermore, considering that the vertical blowing assembly 30 is located in an open air environment (connected to the exit of the upstream tunnel 10), the strip air outlet 330 is an external outlet, so this embodiment also specifically designs a drainage system, such as Figure 2 As shown, the small arrow in the figure is the airflow 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 50×50×80cm, and the size of the overflow well 430 is 100×100×100cm. The drainage well 410 and the overflow well 430 are concrete pools. Preferably, the top surface of the overflow well 430 is 30cm higher than the ground of the drainage well 410 to meet the water sealing requirements. The pool size can be adjusted accordingly.

[0066] As a preferred embodiment, step S2 specifically includes the following steps:

[0067] Using the formula Calculate the first minimum air outlet speed of the vertical blowing assembly 30 when the polluted air 50 is blown upward from the outlet of the upstream tunnel 10 through the vertical blowing assembly 30 and diffuses to the clear height of the tunnel. ,unit: ,in, is the width of the strip air outlet 330, unit: m, is the empirical coefficient, is the net height of the tunnel, unit: m, is the ambient air flow disturbance velocity threshold, unit: .

[0068] It is understood by those skilled in the art that, according to free jet theory and fluid mechanics, after the airflow in the main air duct 320 is ejected from the strip-shaped air outlet 330, there are two development stages:

[0069] ① There is a core stable area near the strip-shaped air outlet 330, where the flow velocity remains basically unchanged.

[0070] For an air outlet that is close to a square (for example, the length of the strip air outlet 330 / Strip air outlet width 330 Less than 5), the core area is close to the law of circular jet, and the length Approximate width 4-6 times, the middle value of 5 times can be taken;

[0071] Core area length = 5× =5×0.0375=0.1875m Formula (1)

[0072] ② There is a velocity attenuation zone outside the core stable zone:

[0073] Outside the core area (distance x>0.1875m), the air velocity decays according to the three-dimensional jet model, and the formula is:

[0074] Formula (2)

[0075] in, For height The corresponding air flow velocity is is an empirical coefficient. As a preferred example, the aspect ratio of the strip-shaped 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. (The circular jet corresponds to =0.16);

[0076] When the airflow velocity decays to the ambient airflow disturbance velocity threshold, preferably, the ambient airflow disturbance velocity threshold The theoretical maximum distance for:

[0077] Formula (3)

[0078] 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.

[0079] Formula (4)

[0080] Therefore, , Substituting into formula (3) and formula (4), and combining the two formulas, we can get , from which the first minimum air outlet velocity of the strip air outlet 330 can be calculated .

[0081] The first minimum air outlet speed calculated in this embodiment Taking full account of 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.

[0082] As a preferred embodiment, step S3 specifically includes the following steps:

[0083] S31, obtaining the ventilation air velocity 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 ;

[0084] S32, according to the ventilation air flow speed and the separation 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 ;

[0085] S33, according to the minimum available time When the polluted air 50 is blown upward from the outlet of the upstream tunnel 10 through the vertical blowing assembly 30 and just diffuses to the clear height of the tunnel, the second minimum air outlet speed of the vertical blowing assembly 30 is determined to be .

[0086] It is worth noting that, in general, the airflow in the tunnel (dirty air 50) is based on the ventilation airflow speed. After exiting the tunnel, there is also a core stable zone and a velocity decay zone. That is, after spreading a certain distance, the polluted air 50 stops spreading downstream. However, if there are vehicles traveling between the upstream tunnel 10 and the downstream tunnel 20, these vehicles will slowly pull the stationary polluted air 50 further toward the downstream tunnel 20. Therefore, the diffusion distance of the polluted air 50 calculated using traditional jet models is too risky.

[0087] In this embodiment, the horizontal movement of the polluted air 50 is assumed to be at the ventilation air flow speed in order to improve the safety resilience of the tunnel. The uniform motion of the tunnel is simulated to simulate the extreme situation of 50% crossflow of polluted air. The final result obtained by considering the most unfavorable situation can meet the requirements of tunnel safety resilience.

[0088] Specifically, the movement distance of the polluted air 50 from the exit of the upstream tunnel 10 to the downstream tunnel 20 is calculated first. :

[0089] Formula (5)

[0090] ①Calculate the movement time of the dirty air 50 (The time for movement in each direction is equal):

[0091] Dirty Wind 50 Movement Speed is the movement distance function, and , so we have:

[0092] Formula (6)

[0093] Separate the variables and integrate:

[0094] Formula (7)

[0095] Initial conditions , (The length of the core area is small and can be ignored). Combining the above formula, the movement time of the polluted air 50 can be calculated. ,when When the corresponding dirty air 50 air flow movement time is , that is, the time required for the polluted air 50 to move from the ground at the tunnel exit to the top of the tunnel (defined as the available time for the horizontal movement of the polluted air 50).

[0096] ②Calculate tunnel ventilation wind speed

[0097] To dilute the CO2 and other pollutants in the tunnel, a fan 310 is installed in the tunnel to form a ventilation airflow. The tunnel ventilation wind speed needs to be determined based on the CO2 emissions, pressure, temperature, tunnel size, etc. The calculation formula is as follows:

[0098] Formula (8)

[0099] Formula (9)

[0100] Usually, hope Less than or equal to 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 diffuse to the downstream tunnel 20 .

[0101] Formula (10)

[0102] In summary, 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 can be calculated. When the minimum available time Less than vertical available time , then 、 、 Substituting into formula (7), the second minimum air outlet speed of the vertical blowing assembly 30 can be calculated as .

[0103] The second minimum air outlet speed calculated in this embodiment Taking full account of the law of horizontal jet of airflow, the second minimum air outlet speed It 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.

[0104] Furthermore, in step S31, the ventilation air velocity in the upstream tunnel 10 is obtained. The specific steps include:

[0105] S311, using formula Calculate the required air volume for diluting the polluted air 50 in the upstream tunnel 10 , unit: m 3 / s; among them, The emission volume of polluted air 50 in the upstream tunnel 10, unit: m 3 / s, is standard atmospheric pressure, unit: kN / m 2 , take 101.325kN / 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 , we can take the local average atmospheric pressure, is the standard temperature, unit: K;

[0106] S312, using formula Get the ventilation air velocity in the upstream tunnel 10 ;in, is the cross-sectional area of ​​the upstream tunnel 10, unit: m 2 .

[0107] Furthermore, the step S5 of determining the total air supply volume of the vertical blowing assembly 30 according to the critical wind speed design value specifically includes the following steps:

[0108] use Determine the total air supply volume of the vertical blowing assembly 30 ;in, is the design value of critical wind speed, unit: , is the number of strip air outlets 330, unit: piece, is the length of the strip air outlet 330, unit: m.

[0109] As another preferred embodiment, the step S5 further includes the following steps:

[0110] S51, obtaining the average wind speed in the main air duct 320, and obtaining the actual air supply volume of the vertical blowing assembly 30 based on the average wind speed ;

[0111] S52, according to the actual air supply volume Get the actual air outlet speed of the strip air outlet 330 ;

[0112] S53, according to the actual air outlet speed 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 assembly 30 is obtained. , and then according to the tunnel clear height and the actual maximum vertical distance Determine the vertical crossflow coefficient of dirty air 50 ;

[0113] S54, according to the actual air speed The actual available time of polluted air 50 is obtained by using the clear height of the tunnel , and then based on the actual available time and ventilation air flow speed Get the actual horizontal movement distance of the polluted wind 50 , and then according to the actual horizontal movement distance of the polluted air 50 Get the horizontal crossflow coefficient of dirty air 50 ;

[0114] S55, according to the vertical crossflow coefficient of dirty air 50 Horizontal crossflow coefficient of 50% and dirty air Get the comprehensive crossflow coefficient of dirty air 50 ;

[0115] S56, based on the comprehensive crossflow coefficient of dirty air 50 Determine the required air volume for diluting the cross-flow polluted air 50 in the downstream tunnel 20 , and then according to the required air volume Determine the number of fans 310 required for the downstream tunnel 20 .

[0116] It is worth noting that during actual tunnel operation, the actual air delivery volume of the fans 310 designed in the aforementioned embodiments may not meet the design requirements due to power system fluctuations, device failures, etc. In such cases, the downstream tunnel 20 needs to further adjust the number of ventilation fans 310 activated in the downstream tunnel 20 based on the crossflow situation to ensure a safe and comfortable driving environment in the downstream tunnel 20.

[0117] Specifically, this embodiment obtains the average wind speed in the main air duct 320 and obtains the actual air supply volume of the vertical blowing assembly 30 according to the average wind speed. Preferably, multiple wind speed detection points can be arranged in the main air duct 320, and the average wind speed obtained from the multiple detection points can be used as the average wind speed, and then the actual air supply volume can be calculated. Get the actual air outlet speed of the strip air outlet 330 , the specific formula can be: Get; then the actual air speed Substituting into formula (2) we can get 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 assembly 30: ;

[0118] You can use the formula Get the vertical crossflow coefficient of dirty air 50 ; Then the actual air speed and Substituting into formula (7), the actual available time of dirty air 50 is calculated as :

[0119] Furthermore, in step S54, the actual horizontal movement distance of the dirty air 50 is Get the horizontal crossflow coefficient of dirty air 50 The specific steps include:

[0120] In actual pollution wind 50 horizontal movement distance Greater than the separation distance When using the formula Get the horizontal crossflow coefficient of dirty air 50 ;

[0121] In actual pollution wind 50 horizontal movement distance Less than or equal to the separation distance When the horizontal crossflow coefficient of dirty air is 50 is 1.

[0122] Furthermore, the step S55 specifically includes the following steps:

[0123] Using the formula Get the comprehensive crossflow coefficient of dirty air 50 .

[0124] Furthermore, the step S56 specifically includes the following steps:

[0125] Using the formula Obtain the required air volume for dilution crossflow polluted air 50 in the downstream tunnel 20 ;

[0126] Using the formula Get the number of fans 310 that need to be added in the downstream tunnel 20 ;in, is the exhaust volume of a single fan 310.

[0127] This embodiment is specifically designed for this special working condition to achieve dynamic regulation based on 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 and avoid blind selection.

[0128] The above are only preferred embodiments of the present invention and are not intended to limit the scope of protection of the present invention. Any equivalent structure or equivalent process transformation made using the contents of the present invention description and drawings, or directly or indirectly applied in other related technical fields, are also included in the scope of protection of the present invention.

Claims

1. A method for suppressing longitudinal dirty air flow in a continuous tunnel, characterized in that: The following steps are involved: S1, a vertical blowing assembly is set at the bottom of the exit of the upstream tunnel; S2, calculating the first minimum air outlet velocity of the vertical blowing assembly when the polluted air is blown upward from the outlet of the upstream tunnel through the vertical blowing assembly and diffuses to the clear height of the tunnel; S3, calculating the second minimum air outlet speed of the vertical blowing assembly when the polluted air discharged from the outlet of the upstream tunnel just diffuses to the entrance of the downstream tunnel; S4, determining the larger value of the first minimum air outlet speed and the second minimum air outlet speed as the critical wind speed design value of the vertical blowing component; S5, determining the total air supply volume of the vertical blowing assembly according to the critical wind speed design value, and then configuring the vertical blowing assembly according to the total air supply volume.

2. The method for suppressing longitudinal dirty air flow in a continuous tunnel according to claim 1, characterized in that: The vertical blowing assembly 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 on the top of the main air duct.

3. The method for suppressing longitudinal dirty air flow in a continuous tunnel according to claim 2, characterized in that: The step S2 specifically includes the following steps: Using the formula Calculate the first minimum air outlet speed of the vertical blowing assembly when the polluted air is blown upward from the outlet of the upstream tunnel through the vertical blowing assembly and just diffused to the clear height of the tunnel. ;in, is the width of the strip air outlet, is the empirical coefficient, is the clear height of the tunnel, is the ambient air flow disturbance velocity threshold.

4. The method for suppressing longitudinal dirty air flow in a continuous tunnel according to claim 2, characterized in that: The step S3 specifically includes the following steps: S31, obtain the ventilation air velocity in the upstream tunnel , and the separation distance between the exit of the upstream tunnel and the entrance of the downstream tunnel ; S32, according to the ventilation air flow speed and the separation distance Calculate the minimum available time for polluted air to diffuse from the exit of the upstream tunnel to the entrance of the downstream tunnel ; S33, according to the minimum available time Determine the second minimum air outlet speed of the vertical blowing assembly when the polluted air is blown upward from the outlet of the upstream tunnel through the vertical blowing assembly and just diffuses to the clear height of the tunnel .

5. The method for suppressing longitudinal dirty air flow in a continuous tunnel according to claim 4, characterized in that: In step S31, the ventilation air velocity in the upstream tunnel is obtained. The specific steps include: S311, using formula Calculate the air volume required to dilute the polluted air in the upstream tunnel ;in, is the amount of polluted air discharged from the upstream tunnel, is 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 formula Get the ventilation air velocity in the upstream tunnel ;in, is the cross-sectional area of ​​the upstream tunnel.

6. The method for suppressing longitudinal dirty air flow in a continuous tunnel according to claim 3, characterized in that: Determining the total air supply volume of the vertical blowing assembly according to the critical wind speed design value in step S5 specifically includes the following steps: use Determine the total air supply volume of the vertical blowing assembly ;in, is the critical wind speed design value, is the number of strip air outlets, is the length of the strip air outlet.

7. The method for suppressing longitudinal dirty air flow in a continuous tunnel according to claim 5, characterized in that: After step S5, the following steps are also included: S51, obtaining the average wind speed in the main air duct, and obtaining the actual air supply volume of the vertical blowing component based on the average wind speed ; S52, according to the actual air supply volume Get the actual air outlet speed of the strip 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 assembly , and then according to the tunnel clear height and the actual maximum vertical distance Determine the vertical crossflow coefficient of dirty air ; S54, according to the actual air speed The actual available time of the polluted air is obtained by using the clear height of the tunnel , and then based on the actual available time and ventilation air flow speed Get the actual horizontal movement distance of the polluted air , and then according to the actual horizontal movement distance of the polluted air Get the horizontal crossflow coefficient of dirty air ; S55, based on the vertical crossflow coefficient of polluted air Horizontal crossflow coefficient of polluted air Get the comprehensive crossflow coefficient of dirty air ; S56, based on the comprehensive crossflow coefficient of polluted air Determine the required air volume for dilution and cross-flow of polluted air in the downstream tunnel , and then according to the required air volume Determine the number of fans required in the downstream tunnel .

8. The method for suppressing longitudinal dirty air flow in a continuous tunnel according to claim 7, characterized in that: In step S54, the actual horizontal movement distance of the dirty air is determined according to the Get the horizontal crossflow coefficient of dirty air The specific steps include: In actual horizontal movement distance of polluted air Greater than the separation distance When using the formula Get the horizontal crossflow coefficient of dirty air ; In actual horizontal movement distance of polluted air Less than or equal to the separation distance When the horizontal crossflow coefficient of dirty air is is 1.

9. The method for suppressing longitudinal dirty air flow in a continuous tunnel according to claim 7, characterized in that: The step S55 specifically includes the following steps: Using the formula Get the comprehensive crossflow coefficient of dirty air .

10. The method for suppressing longitudinal dirty air flow in a continuous tunnel according to claim 7, characterized in that: The step S56 specifically includes the following steps: Using the formula Obtain the required air volume for dilution and crossflow of polluted air in the downstream tunnel ; Using the formula Get the number of fans that need to be added in the downstream tunnel ;in, The exhaust volume of a single fan.

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