Subway tunnel thermal pollution monitoring system and monitoring method

Abstract

The invention relates to the technical field of civil engineering, and provides a subway tunnel thermal pollution monitoring system and method, and the method comprises the following steps: obtaining the air temperature in a tunnel and the geometric deformation data of the inner wall surface of the tunnel; the obtained air temperature data and deformation data are subjected to fusion analysis processing, and the thermal pollution degree in the tunnel is determined; and according to the judgment result of the thermal pollution degree in the tunnel, the operation mode of a heat pump unit arranged in the tunnel is controlled in combination with the obtained outdoor air temperature data and the air heat storage amount in the tunnel. According to the method, the air temperature, the wall surface deformation rate and the thermal pollution degree are comprehensively considered, so that the thermal pollution of the environment in the tunnel is accurately monitored.

Description

Technical Field

[0001] The present disclosure relates to the technical field related to civil engineering, and in particular, to a subway tunnel thermal pollution monitoring system and a monitoring method. Background Art

[0002] The statements in this section merely provide background information related to the present disclosure and do not necessarily constitute prior art.

[0003] At present, a large amount of heat is generated during subway operation due to acceleration, braking, air conditioning, etc. As waste heat accumulates in the tunnel, the temperature in the tunnel gradually rises, and the energy consumption of the subway environmental control system increases year by year, seriously affecting the operation of the subway. Some subway lines have already experienced serious thermal pollution problems, with the temperature in the tunnel reaching over 40°C, seriously affecting the normal operation of the subway; in addition, thermal pollution will cause the temperature in the tunnel depth direction to continue to rise, causing structural material fatigue of the tunnel lining under periodic heating and cooling, destroying the stability and durability of the tunnel structure, and even causing cracks, destroying the waterproofing of the tunnel. Therefore, it is necessary to reasonably monitor and control thermal pollution in subway tunnels.

[0004] The inventors found in their research that although subway tunnels are currently equipped with ventilation systems or subway source heat pump unit systems to control the thermal environment of subway tunnels, the operation of the above-mentioned systems is basically based on a fixed mode of scheduled start, resulting in poor control of tunnel thermal pollution and energy waste. Through the existing subway tunnel ventilation system or subway source heat pump unit system, it is impossible to obtain detailed information on the changes in the thermal environment in the subway tunnel, and thus it is impossible to formulate effective measures to discharge the heat in the tunnel, and it is impossible to understand the deformation of the rock mass around the tunnel under the action of thermal stress. Summary of the invention

[0005] In order to solve the above problems, the present invention proposes a subway tunnel thermal pollution monitoring system and monitoring method, which realizes accurate monitoring of the thermal pollution in the tunnel environment by comprehensively considering the air temperature, wall deformation rate and thermal pollution degree.

[0006] In order to achieve the above objectives, the present disclosure adopts the following technical solutions:

[0007] One or more embodiments provide a method for monitoring thermal pollution in a subway tunnel, comprising the following steps:

[0008] Obtain the air temperature in the tunnel and the geometric deformation data of the tunnel wall;

[0009] The acquired air temperature data and deformation data are fused and analyzed to determine the degree of thermal pollution in the tunnel;

[0010] According to the results of the judgment of the degree of thermal pollution in the tunnel, combined with the obtained outdoor air temperature data and the heat storage capacity of the air in the tunnel, the operation mode of the heat pump unit installed in the tunnel is controlled.

[0011] One or more embodiments provide a subway tunnel thermal pollution monitoring system, including a control terminal, a collection device arranged in the tunnel, and a heat pump unit;

[0012] A collection device for collecting environmental data in the tunnel, including at least the temperature in the tunnel and the geometric deformation data of the tunnel;

[0013] The control terminal executes the above-mentioned subway tunnel thermal pollution monitoring method according to the data collected by the collection device, and controls the operation of the heat pump unit to achieve cold storage or heat storage;

[0014] One or more embodiments provide a subway tunnel thermal pollution monitoring system, including:

[0015] Data acquisition module: configured to acquire the air temperature in the tunnel and the geometric deformation data of the wall surface in the tunnel;

[0016] Thermal pollution degree judgment module: configured to perform fusion analysis and processing on the acquired air temperature data and deformation data to determine the degree of thermal pollution in the tunnel;

[0017] Control module: It is configured to control the operation mode of the heat pump unit installed in the tunnel according to the result of judging the degree of thermal pollution in the tunnel, combined with the acquired outdoor air temperature data and the heat storage amount of the air in the tunnel.

[0018] Compared with the prior art, the present invention has the following beneficial effects:

[0019] The present disclosure realizes accurate monitoring of thermal pollution in the tunnel environment by comprehensively considering air temperature, wall deformation rate and thermal pollution degree. Compared with single parameter monitoring, this method improves the accuracy of thermal pollution judgment. At the same time, the operation of the heat pump unit is controlled in combination with the outdoor air temperature and the heat storage capacity, which not only optimizes the thermal environment inside the tunnel, but also effectively alleviates the erosion problem of the tunnel wall caused by thermal stress, improves the operational reliability of the tunnel system and the long-term operational efficiency of subway trains. In addition, by dynamically adjusting the operating parameters, the energy consumption of the heat pump unit is reduced, and the energy-saving effect of the system is improved.

[0020] The advantages of the present disclosure and the advantages of additional aspects will be described in detail in the following specific embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] The accompanying drawings constituting a part of the present disclosure are used to provide a further understanding of the present disclosure. The exemplary embodiments of the present disclosure and the description thereof are used to explain the present disclosure but do not constitute a limitation of the present disclosure.

[0022] Figure 1 is a flow chart of the monitoring method of Embodiment 1 of the present disclosure;

[0023] Figure 2 is a flow chart of a method for determining the degree of thermal pollution in Embodiment 1 of the present disclosure;

[0024] Figure 3 is a flow chart of thermal pollution control of Example 1 of the present disclosure;

[0025] Figure 4 is a schematic diagram of the installation of the collection device of Embodiment 2 of the present disclosure in a tunnel;

[0026] Figure 5 is a planar wiring diagram of the sensor of the acquisition device of Embodiment 2 of the present disclosure;

[0027] Figure 6 is a partial installation diagram of the optical fiber deformation sensor 7 of Embodiment 2 of the present disclosure;

[0028] Figure 7 It is a partial installation diagram of the thermocouple sensor 6 of the embodiment 2 of the present disclosure;

[0029] Figure 8 is a partial installation diagram of the anemometer 14 of Embodiment 2 of the present disclosure;

[0030] Fig. 9 This is a schematic diagram of the local installation and connection of the heat flow meter 16 of the second embodiment of the present disclosure.

[0031] Among them: 1. surrounding rock; 2. outer wall of energy tunnel segment; 3. energy tunnel segment layer; 4. inner wall of energy tunnel pipe; 5. fixed bracket; 6. thermocouple sensor; 7. optical fiber deformation sensor; 8. transmission wire; 9. deformation signal transmission optical cable; 10. temperature transmitter; 11. equipment boundary; 12. thermocouple sensor compensation wire; 13. transmission optical fiber; 14. anemometer; 15. wind speed signal transmission wire; 16. heat flow meter; 17. heat flow signal transmission wire. DETAILED DESCRIPTION

[0032] The present disclosure is further described below in conjunction with the accompanying drawings and embodiments.

[0033] It should be noted that the following detailed descriptions are exemplary and are intended to provide further explanation of the present disclosure. Unless otherwise specified, all technical and scientific terms used herein have the same meanings as those commonly understood by those skilled in the art to which the present disclosure belongs.

[0034] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit exemplary embodiments according to the present disclosure. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should be understood that when the terms "comprising" and / or "including" are used in this specification, it indicates the presence of features, steps, operations, devices, components and / or combinations thereof. It should be noted that, in the absence of conflict, the various embodiments in the present disclosure and the features in the embodiments can be combined with each other. The embodiments will be described in detail below in conjunction with the accompanying drawings.

[0035] Example 1

[0036] In the technical solutions disclosed in one or more embodiments, Figures 1 to 3 As shown, a method for monitoring thermal pollution in a subway tunnel comprises the following steps:

[0037] Step 1, obtaining the air temperature in the tunnel and the geometric deformation data of the inner wall of the tunnel;

[0038] Step 2: Fusion analysis and processing of the acquired air temperature data and deformation data to determine the degree of thermal pollution in the tunnel;

[0039] Step 3: Based on the result of the thermal pollution degree in the tunnel, combined with the acquired outdoor air temperature data and the air heat storage capacity in the tunnel, the operation mode of the heat pump unit installed in the tunnel is controlled.

[0040] This embodiment obtains the air temperature growth rate and the deformation rate of the tunnel wall, and then obtains the degree of thermal pollution in the tunnel. According to the degree of thermal pollution in the tunnel and in combination with the outdoor air temperature, the subway heat pump unit system is adjusted for operating parameters, providing a suitable tunnel environment for the long-term and efficient operation of subway trains, solving the problems of heat accumulation in the tunnel leading to difficulties in train air conditioning operation and erosion of the tunnel wall, thereby improving the control accuracy of tunnel thermal pollution.

[0041] In step 1, data collection can be performed by setting up different collection devices in the subway tunnel, including:

[0042] The first collecting device is used to collect the air temperature in the tunnel;

[0043] Specifically, the first acquisition device includes a communication-connected thermocouple sensor 6 and a temperature transmitter 10. The thermocouple sensors 6 are evenly arranged on the cross section of the tunnel. The thermocouple sensors 6 are set on the tunnel wall in a direction perpendicular to the inner wall of the tunnel by a fixing bracket 5.

[0044] It is feasible that, since the tunnel is circular, thermocouple sensors 6 are arranged on one symmetrical side of the tunnel, and a number of thermocouple sensors 6 (for example, 3) are evenly arranged on the cross section of the tunnel at a certain distance (for example, 5 meters), and 3 fixed brackets 5 are arranged accordingly, and the three thermocouple sensors 6 are arranged at the bottom, middle and top of one side of the tunnel respectively; the arrangement direction of the thermocouple sensors 6 is perpendicular to the inner wall direction of the tunnel, and the brackets 5 are used to fix them on the tunnel segment grooves, and are equipped with protective sleeves, and K-type thermocouple sensor compensation wires 12 are laid along the tunnel section to collect from each thermocouple sensor to the temperature transmitter 10 on one side of the tunnel, and the first acquisition device is a temperature sensing detection device, and it is difficult to transmit wireless signals in the tunnel, so wired connection is selected between the thermocouple sensors 6;

[0045] The second acquisition device is used to acquire geometric deformation data of the inner wall surface of the tunnel surrounding rock;

[0046] Specifically, the second acquisition device uses an optical fiber deformation sensor 7, and a plurality of optical fiber deformation sensors 7 are evenly arranged on the cross section of the tunnel at intervals;

[0047] A specific implementation method is to use optical fiber deformation sensors 7. Several (for example, 6) optical fiber sensors 7 are evenly arranged on the cross section of the tunnel at a certain distance (for example, 5 meters), and external protection is provided for the buried optical fiber sensors 7. Optical fiber cables are used as pigtails to lead out the energy tunnel pipe layer; strain sensing bolts are established on the tunnel wall, equipped with ceramic ferrules, and connected to the transmission optical fiber 13. The third acquisition device is a stress sensor. Considering that wireless signals are difficult to transmit in the tunnel, the optical fiber deformation sensors 7 are connected by wire.

[0048] The third collection device is used to collect the cold storage and heat storage in the tunnel;

[0049] Specifically, the third collection device can be an ultrasonic calorimeter for collection. The calorimeter is installed on the supply and return water pipes on the source side of the heat pump unit. The heat storage amount in the tunnel is obtained by calculating the heat difference between the supply and return water.

[0050] The fourth collecting device is used to collect the heat per unit area of ​​the contact surface between the inner wall of the tunnel and the air in the tunnel;

[0051] Specifically, the fourth acquisition device may be a heat flow meter 16. The heat flow meter 16 is arranged on the tunnel wall, and a set number of heat flow meters 16 are arranged at set intervals in the extension direction of the tunnel;

[0052] A feasible technical solution is to arrange three heat flow meters 16 every 10 meters. The heat flow meters 16 are connected to the control terminal through wires to control the thermal pollution of the tunnel through the collected data.

[0053] The fifth collection device is used to collect the wind speed in the tunnel;

[0054] Specifically, the fifth acquisition device adopts an anemometer 14, which is installed on the top of the tunnel. An anemometer 14 is arranged every 20 meters. The anemometer 14 transmits the monitored tunnel wind speed signal to the control terminal through a DC wire.

[0055] In step 2, if Figure 2 As shown, the method for determining thermal pollution in a subway tunnel includes:

[0056] Step 21: Determination of severe thermal pollution:

[0057] If one of the temperature growth rate in the tunnel and the deformation rate of the inner wall of the tunnel surrounding rock exceeds the maximum value of the set threshold range, it is judged as severe thermal pollution;

[0058] Step 22: Method for determining moderate thermal pollution:

[0059] If neither the temperature growth rate in the tunnel nor the deformation rate of the inner wall of the tunnel surrounding rock exceeds the maximum value of the set threshold range, and one of them does not exceed the set threshold range, it is judged as moderate thermal pollution;

[0060] Step 23: Determination of mild thermal pollution:

[0061] If the temperature growth rate in the tunnel and the deformation rate of the inner wall of the tunnel surrounding rock do not exceed the set threshold range, it is judged as mild thermal pollution.

[0062] A specific implementation method of step 2 above is as follows: Figure 2 As shown;

[0063] Firstly, the temperature growth rate in the tunnel and the deformation rate of the inner wall of the tunnel surrounding rock are calculated;

[0064] The temperature growth rate in the tunnel is calculated as follows: the average tunnel temperature T within a set period of time (such as one year) aver The rate of change relative to the initial value T0 of the tunnel temperature is calculated as:

[0065]

[0066] The deformation rate of the inner wall of the tunnel surrounding rock is calculated as follows: the maximum value of the tunnel deformation within a set time (such as one year) L cmax The rate of change relative to the initial tunnel wall length L0 is calculated as:

[0067]

[0068] Furthermore, the threshold of the temperature change rate is set to θ1(a, b), and the threshold of the deformation change rate is set to θ2(c, d);

[0069] When △t > b or △s > d, it is determined as severe heat pollution; otherwise, when a < △t < b and △s < d or △t < b and c < △s < d, it is judged as moderate heat pollution; otherwise, it is determined as mild heat pollution;

[0070] In step 3, according to the degree of heat pollution and the heat storage capacity in the tunnel, adjust the control method of the subway source heat pump unit system:

[0071] If the degree of heat pollution is severe heat pollution or moderate heat pollution, combined with the amount of accumulated heat storage in the tunnel air monitored, any one of the following four control strategies is implemented to control heat pollution:

[0072] (A1) The first one: In the next cooling season, reduce the operating power of the subway source heat pump unit system to reduce the heat storage in the tunnel air; calculate the amount of heat storage reduction according to the heat storage in the tunnel air within the set time period, the duration of the cooling season, and the average heat flux density between the tunnel wall and the air in the cooling season;

[0073] In this embodiment, the cooling season is the summer, and there is sufficient heat in this season, so heat storage is required through the heat pump unit;

[0074] Specifically, set the power of the set unit in the next cooling season to be (1 - β1) times, and the calculation formula of β1 is as follows:

[0075]

[0076] Where: Q x is the heat storage in the tunnel air when reaching the next cooling season, J; d c is the duration of a cooling season, s; is the average heat flux density between the tunnel wall and the air in a cooling season, W; in this embodiment, each symbol after the explanation conforms to the unit, such as Q x is the heat storage in the tunnel air, J; indicating that Q x has the unit of J;

[0077] Q x is the heat storage in the set calculation period, which can be set to one year, such as from November 14 this year before the start of the heating season to November 14 next year as a cycle;

[0078] (A2) The second one: In the next heating season, increase the power of the subway source heat pump unit system to increase the heat extraction in the tunnel; calculate the amount of increased heat storage according to the heat storage in the tunnel air within the set time period, the duration of the heating season, and the average heat flux density between the tunnel wall and the air in the heating season;

[0079] Specifically, set the power of the set unit in the next cooling season to be (1 + β2) times, and the calculation formula of β2 is as follows:

[0080]

[0081] Where: Q x The heat storage of tunnel air until the next heating season, J; d h is the length of a heating season, s; is the average heat flux density between the tunnel wall and air during the heating season, W;

[0082] In this embodiment, the heating season is winter, and there is sufficient heat in this season, so it is necessary to store cold through the heat pump unit;

[0083] (A3) The third method is to shorten the operation time of the subway source heat pump system in the next cooling season to reduce the heat storage of the air in the tunnel. The reduced time is calculated by the heat storage of the tunnel air and the average heat flux density between the tunnel wall and the air in the previous cooling season.

[0084] That is, shorten H1 hours in the next cooling season. The calculation formula of H1 is as follows:

[0085]

[0086] Where: Q x To achieve the tunnel air heat storage capacity in the next cooling season, J; is the average heat flux density between the tunnel wall and air in the previous cooling season, W;

[0087] (A4) The fourth method is to extend the operation time of the subway source heat pump system in the next heating season to increase the cooling capacity of the air in the tunnel. The extended time is calculated through the heat storage of the tunnel air and the average heat flux density between the tunnel wall and the air in the previous cooling season.

[0088] That is, the next heating season will be extended by H2 hours. The calculation formula of H2 is as follows:

[0089]

[0090] Where: Q x Heat storage for tunnel air, J; is the average heat flux density between the tunnel wall and air in the previous heating season, W;

[0091] If the degree of thermal pollution is mild, combined with the value of the monitored accumulated heat storage of the air in the tunnel, any of the following two control strategies is implemented to control the thermal pollution:

[0092] For mild thermal pollution, by monitoring the heat storage of the air in the tunnel, one of the following two operation strategies can be used:

[0093] (B1) The first one: maintain the existing operation strategy;

[0094] (B2) The second method is to dynamically adjust the heating season heat intake and cooling season heat storage to improve the efficiency of the heat pump system without increasing heat pollution. The heating season heat intake calculation method is the same as the above A2 scheme; the cooling season heat storage calculation method is the same as the above A1 scheme, which will not be repeated here;

[0095] The above-mentioned thermal pollution control method is not a real-time control, but an operation control plan for the subway source heat pump unit system in the next cooling and heating cycle is formulated through the tunnel wall temperature growth rate, the deformation rate of the tunnel surrounding rock 1, and the amount of cold and heat stored in the tunnel after the previous heating and cooling cycle.

[0096] Further technical solution, the air heat storage in the tunnel Q x Q is the heat exchange between the tunnel wall and the tunnel air h 、Heat generated by heat source in tunnel Q n 、The amount of heat exchange in tunnel ventilation Q f The sum of the integrals of is calculated as follows:

[0097] Q x =∫Q h dt+∫Q n dt+∫Q f dt

[0098] Where: Q h is the heat exchange between the tunnel wall and the tunnel air; Q n Heat generated by heat source in the tunnel; Q f Provide heat exchange for ventilation in tunnels;

[0099] In some embodiments, Q h The value can be calculated by the following formula:

[0100]

[0101] Q h =q×S

[0102] Among them, q i is the detection value at the i-th moment; q is the average value of the detection value of the heat flow meter 16, in units of W / ㎡; S is the tunnel area;

[0103] In some embodiments, the heat source in the tunnel generates heat Q n The value of is the sum of the heat generated by train operation and the heat generated by tunnel lighting;

[0104] During subway operation, the heat source in the tunnel will generate a lot of heat and release it into the air, causing the air temperature to rise. This heat source is mainly divided into two parts: train operation and tunnel lighting. Train operation is the main heat source in the subway tunnel, and its heat generation accounts for more than 90% of the total heat generation of the heat source in the tunnel.

[0105] 1. Heat generated by train operation;

[0106] Specifically, the heat generated by train operation includes the following according to the heat sources: the first category is the heat generated by the train to overcome resistance, including the heat generated by overcoming friction resistance during the starting phase, acceleration phase, constant speed phase and braking phase, as well as the heat generated by air resistance during the running phase of the train; the second category is the heat generated by the train's supporting equipment, including heat generated by auxiliary equipment, heat generated by air-conditioning equipment, and heat generated by personnel and lighting equipment.

[0107] (1) Heat generation by starting resistance:

[0108] During the train startup process, the oil film between the train axle and the bearing is destroyed, and the train generates heat due to overcoming friction resistance. The heat generation calculation formula is as follows:

[0109] Q1=9.8r1·M·l1

[0110] In the formula: Q1 is the heat generated by the starting resistance of a single train, in kJ; r1 is the starting resistance coefficient of the train, which is 1.5-3 per ton of vehicle weight; M is the total weight of a single train, in tons; l1 is the distance traveled by the train during the starting phase, in meters (m).

[0111] (2) Heat generated by acceleration and braking resistance:

[0112] During the train acceleration phase, part of the electrical energy is converted into heat due to the existence of frictional resistance; during the train braking phase, part of the kinetic energy is recovered and converted into electrical energy due to the existence of the regenerative braking device, and the remaining kinetic energy is converted into heat due to the existence of frictional resistance. The heat generated by the train acceleration is calculated to be about half of the heat generated by the brake. The heat generation calculation formula for the train acceleration and braking phases is as follows:

[0113]

[0114] Where: Q2 is the heat generated by the acceleration and braking resistance of a single train, in kJ; α is the braking regeneration coefficient of the train, which can be 0.4-0.5; v1 is the speed of the train at the beginning of the braking phase, in m / s; v2 is the speed of the train at the end of the braking phase, in m / s.

[0115] When the above formula is divided by 2 during the acceleration phase, the speed corresponds to the starting speed of acceleration and the speed after acceleration;

[0116] (3) Heat generated by uniform resistance:

[0117] The resistance of a train traveling at a constant speed mainly comes from the friction between the bearings and the axles, the friction between the rails and the wheels, etc. The electric energy consumed by the train to overcome the friction resistance is converted into heat. The heat generation calculation formula is as follows:

[0118] Q3=9.8r3·M·l3

[0119] In the formula: Q3 is the uniform speed resistance heat generated by a single train, kJ; r3 is the uniform speed resistance coefficient of the train, which is 1.5-3 per ton of vehicle weight; l3 is the distance traveled by the train in the uniform speed stage, m.

[0120] (4) Heat generated by air resistance:

[0121] During the train operation phase, part of the electrical energy is converted into heat due to the existence of air resistance. The heat generation calculation formula is as follows:

[0122] Q4=0.00065M·(3-0.0069)·V t -1.65(1-V t / V m )·V t

[0123] Where: Q4 is the heat generated by air resistance during the operation of a single train, kJ; V t is the average speed of the train running in the section tunnel, m / s; V m is the maximum design speed of the train, m / s.

[0124] (5) Heat generation of air conditioning unit:

[0125] To ensure the comfort of passengers in the cooling season, the train uses air conditioning equipment to discharge the heat inside the train to the interior of the section tunnel. The heat generation calculation formula is as follows:

[0126] Q5=2M·n·τ s

[0127] Where: Q5 is the heat generated by the air conditioner during the operation of a single train, kJ; M is the power of each air conditioner, kW; n is the number of train formations, knots; τ s is the operating time of the air conditioning unit, s.

[0128] (6) Heat generation of auxiliary equipment

[0129] During the efficient operation of the train, the operation of auxiliary equipment such as air compressors, motor units, controllers, etc. will also generate a lot of heat. The calculation formula for the heat generation is as follows:

[0130]

[0131] Where: Q6 is the heat generation of auxiliary equipment of a single train, kJ; M g is the output power of the motor, kW; f is the load factor; η is the motor efficiency.

[0132] (7) Heat generation by personnel and lighting equipment:

[0133] During the heating season and transition season, the air conditioning equipment in the train is turned off. At this time, the heat generated by the passengers and lighting inside the train needs to be considered. The number of passengers varies greatly at different times. By referring to the rated passenger capacity and full passenger capacity of the Type B train in the demonstration project, the number of passengers at different times of the week can be determined [59-61]. The calculation formula for the heat generated by train personnel and lighting equipment is as follows:

[0134] Q7=(q p ·d·n+g·n)·τ s

[0135] Where: Q7 is the heat generated by the personnel and lighting equipment in the train, kJ; q p is the heat dissipation of each passenger in the train, set to 0.15kW / person; d is the number of passengers in the train, person / section; g is the lighting power of the train, set to 1.6kW / section.

[0136] 2. Heat generated by tunnel lighting;

[0137] To ensure a visible working environment, lighting lamps are placed in the tunnels. Part of the electrical energy is converted into heat during the lighting process. The heat generation calculation formula is as follows:

[0138] Q8=l·q l ·τ l

[0139] Where: Q8 is the lighting heat generation of the interval tunnel, kJ; l is the length of the interval tunnel, m; q l is the lighting index of the interval tunnel, generally 6kW / km; τ l is the tunnel lighting time, s.

[0140] The heat generation of train operation and tunnel lighting is calculated above respectively. The above heat generation data are fused below. Specifically, the heat generation of the tunnel is divided into acceleration section, uniform speed section and braking section to obtain the heat generation of the internal heat source per unit length in each section of the tunnel under train operation. Then, the heat generation of the heat source in each section of the tunnel within a set time (such as 1h) is calculated. Assuming that the heat generation of the heat source in the tunnel is evenly distributed in the section and evenly distributed within the set time, the hourly heat generation of the heat source in each section is obtained as the heat generation Q of the heat source in the tunnel. n The value of

[0141] Due to the influence of the train operation stage, there is a large difference in the heat generation of internal heat sources at different positions in the tunnel. According to the train operation stage, the tunnel can be divided into three sections: acceleration section, constant speed section and braking section.

[0142] Assuming that the heat generated by the internal heat source is evenly distributed in the tunnel sections, the heat generated by the train's starting and acceleration resistance, uniform speed resistance, and braking resistance are allocated to the tunnel's acceleration section, uniform speed section, and braking section respectively; the heat generated by air-conditioning equipment, personnel and lighting equipment, tunnel lighting, and air resistance are allocated to the tunnel's acceleration section, uniform speed section, and braking section according to the proportion of the train's running time in each tunnel section.

[0143] Based on the above calculation method, the heat generation per unit length of the internal heat source in each section of the tunnel under the condition of a single train running can be obtained. The calculation formula is as follows:

[0144] Tunnel acceleration section:

[0145]

[0146] Tunnel uniform speed section:

[0147]

[0148] Tunnel braking section:

[0149]

[0150] Where: F j 、F y 、F z are the heat generation per unit length of the internal heat source in the acceleration section, uniform speed section and braking section of the tunnel under the condition of a single train running, W / m; τ j , τ y , τ z are the running time of a single train in the acceleration section, constant speed section, and braking section of the tunnel, s; τ a is the total running time of a single train in the acceleration section, constant speed section and braking section of the tunnel, s.

[0151] Considering the impact of train running on the data, the heat generation of the internal heat source in each section of the tunnel varies greatly in different time periods. Based on the heat generation of the internal heat source in each section of the tunnel under the condition of a single train running and the number of trains running, the heat generation of the heat source in each section of the tunnel within 1 hour can be obtained. Assuming that the heat generation of the heat source in the tunnel is evenly distributed in the section and evenly distributed within 1 hour, the hourly heat generation of the heat source in each section is calculated as follows:

[0152]

[0153] Where: E x F is the hourly heat generation of the internal heat source per unit length in the tunnel acceleration section (uniform speed section or braking section), W / m; xis the heat generated by the internal heat source per unit length of the tunnel acceleration section (constant speed section or braking section) under the condition of a single train running, W / m; b is the number of train pairs running within 1 hour; q cx It is the hourly heat generated by the train running per unit length in the tunnel acceleration section (uniform speed section or braking section), W / m.

[0154] Assuming that the heat generated by the heat source in the tunnel is evenly distributed in the axial direction of the tunnel, the hourly heat generated by the heat source per unit length of the interval tunnel can be calculated:

[0155]

[0156] Where: q c It is the hourly heat generated by train running per unit length in the interval tunnel, W / m.

[0157] In some embodiments, the ventilation heat exchange rate in the tunnel is Q f The value of is calculated by the temperature of the tunnel ventilation inlet and ventilation outlet;

[0158] Due to the piston effect caused by the running of the train and the operation of the tunnel fan, the air enters the interval tunnel through the air shaft and flows continuously along the tunnel, and finally exits the interval tunnel through the air shaft. In this process, the tunnel air absorbs the heat generated by the internal heat source and exchanges heat with the tunnel wall, causing the air temperature to change when entering and exiting the tunnel.

[0159] To simplify the calculation, the following assumptions are made: the air shaft is located near the station and there is no ventilation equipment inside the section tunnel; the tunnel air is an incompressible fluid; the mass flow rate of the tunnel air is constant during the process of entering and exiting the section tunnel. The ventilation heat exchange of air per unit length of the tunnel is:

[0160] Q f =c q ·G·(T in -T out )

[0161] G=ρ q ·v q ·S t

[0162]

[0163] Where: T in is the temperature at the tunnel entrance, °C, T out is the temperature at the tunnel exit, °C, c q is the constant pressure specific heat capacity of tunnel air, J / (kg·K); G is the mass flow rate of tunnel air, kg / s; ρ q is the density of tunnel air, kg / m3; v qis the average value monitored by each anemometer 14 in the interval tunnel, m / s; S t is the cross-sectional area of ​​the interval tunnel section, m 2 .

[0164] In the control method of this embodiment, the heat source and loss of the air in the tunnel mainly come from three aspects. The first is from the tunnel wall. The capillary network in the tunnel wall will release and absorb heat in the tunnel air during the cooling season and the heating season. The heat flow meter 16 is used to monitor the size q of this heat flow (introduced in the previous formula) and calculate Q h , through Q h The second is the heat generated by the internal heat source of the tunnel, Q n The calculation formula has been given above. The third type of heat exchange from the ventilation in the tunnel is Q f By integrating the above three sources of heat, the heat storage Q of the tunnel air in one cycle can be obtained. x Based on the collected heat flux density data of the tunnel air and the tunnel wall, the average heat flux density in the cooling season and the heating season is calculated. and The heat storage is divided by the duration of the entire cooling season or heating season and then divided by the average heat flux density of the cooling season or heating season. or Thus, a coefficient β1 or β2 is obtained. The heat pollution can be controlled by reducing the power of the heat pump unit in the cooling season to (1-β1) times the previous one, or by increasing the power of the heat pump unit in the heating season to (1+β2) times the previous one. This method is achieved by controlling the unit power. In addition, the air heat pollution in the tunnel can be improved by reducing the operating time of the heat pump in the cooling season and increasing the operating time of the heat pump in the heating season. That is, using the heat storage Q x Divided by the average heat flux density during the cooling or heating season or H1 or H2 is obtained, H1 is the reduced operation time of the heat pump in the cooling season, and H2 is the increased operation time of the heat pump in the heating season. Through the above control method, effective control of thermal pollution in subway tunnels is achieved.

[0165] Example 2

[0166] Based on Example 1, this embodiment provides a subway tunnel thermal pollution monitoring system, such as Figures 4 to 9 As shown, it includes a control terminal, a collection device arranged in the tunnel, and a heat pump unit;

[0167] The collecting device is used to collect environmental data in the tunnel, including at least the temperature and geometric deformation data in the tunnel;

[0168] The control terminal identifies the degree of thermal pollution in the tunnel based on the data collected by the acquisition device to control the heat pump unit accordingly.

[0169] The control terminal executes the subway tunnel thermal pollution monitoring method described in Example 1 according to the data collected by the collection device, and controls the operation of the heat pump unit to achieve cold storage or heat storage;

[0170] In some embodiments, a specific setting example of the acquisition device is given in this embodiment:

[0171] The first collection device collects the air temperature in the tunnel. The installation positions of its various components are as follows: Figure 4 and Figure 7 As shown, the arrangement of the system in the tunnel is that three thermocouple sensors 6 and a temperature transmitter 10 are arranged every five meters, wherein the thermocouple sensors are arranged on one side of the tunnel:

[0172] The first thermocouple sensor 6 is arranged on the tunnel wall at a vertical distance of 0.6m to 1m from the tunnel bottom and from the inner wall 4 of the energy tunnel tube. The thermocouple sensor 6 is fixed on the tunnel wall by a fixing bracket 5 or installed on the tunnel wall groove (this embodiment only provides a schematic diagram of the fixing bracket) to measure the air temperature at the bottom of the tunnel;

[0173] The second thermocouple sensor 6 is arranged at a distance from the tunnel top and installed on the tunnel wall at a vertical distance of 0.2m to 0.5m from the inner wall 4 of the energy tunnel layer at the tunnel top. The thermocouple sensor 6 is fixed with a bracket 5 or installed in a tunnel wall groove to monitor the air temperature at the tunnel top.

[0174] The third thermocouple sensor 6 is installed on the tunnel side wall between the first thermocouple sensor 6 and the second thermocouple sensor 6. The thermocouple sensor 6 is fixed by a fixing bracket 5 or installed in a tunnel wall groove to monitor the air temperature in the middle of the tunnel.

[0175] The temperature transmitter 10 is installed on the upper part of the first thermocouple sensor 6, with a distance of 0.3m to 0.4m from the first thermocouple sensor 6, and can be fixed in the groove of the energy tunnel segment. The thermocouple sensor 6 is connected to the temperature transmitter 10 through the thermocouple sensor compensation wire 12. The signal passes through the temperature transmitter 10 and then is transmitted to the machine room via the transmission wire 8 for signal analysis. The transmission wires 8 of all temperature transmitters 10 in the entire tunnel are installed on the wall 0.1m below the temperature transmitter 10 through the fixing bracket 5;

[0176] Furthermore, the second acquisition device is used to collect geometric deformation data of the inner wall surface of the tunnel surrounding rock; the following are the installation positions and connection methods of the various components of the second acquisition device; the energy tunnel pipe includes: the outer wall 2 of the energy tunnel pipe segment, the energy tunnel pipe segment layer 3 and the inner wall 4 of the energy tunnel pipe; all the acquisition devices are installed within the equipment boundary 11;

[0177] The installation method in the tunnel is to install 6 optical fiber deformation sensors 7 every 5m. Figure 1 As shown, the horizontal distance between the thermocouple sensor 6 and the optical fiber deformation sensor 7 can be set to 2.5 m.

[0178] In this embodiment, six optical fiber deformation sensors 7 are set as an example and are evenly arranged in the energy tunnel segment layer 3 .

[0179] The optical fiber deformation sensors 7 are installed at the upper, middle and lower parts of the tunnel cross section. The two lower optical fiber deformation sensors 7 are installed on both sides of the tunnel wall at a vertical distance of 0.2m to 0.3m from the bottom of the energy tunnel inner wall 4, and the installation positions of the two optical fiber deformation sensors 7 are symmetrical; the two middle optical fiber deformation sensors 7 are installed in the wall surface of the energy tunnel inner wall 4 on both sides of the center point in the tunnel; the upper two sensors are installed on both sides of the energy tunnel inner wall 4 at a vertical distance of 0.2m to 0.3m from the inner wall of the top energy tunnel layer, and the installation positions of the two optical fiber deformation sensors 7 are symmetrical. The approximate installation positions of the optical fiber deformation sensors are as follows: Figure 6 shown.

[0180] The following introduces the connection method of each optical fiber deformation sensor 7. Each optical fiber deformation sensor 7 uses an optical fiber cable as a pigtail to lead out of the energy tunnel pipe layer 3, and establishes a strain sensing bolt on the inner wall 4 of the energy tunnel pipe, equipped with a ceramic ferrule to connect the internal sensing optical fiber and the external transmission optical fiber 13. The transmission optical fibers 13 of the six sensors are unified and concentrated to the deformation signal transmission optical cable 9 on the left side of the tunnel top through the external transmission optical fiber 13. The transmission optical cable 9 is installed on the left side of the tunnel wall at a vertical distance of 0.5m to 0.6m from the inner wall 4 of the top energy tunnel layer, and is fixed to the tunnel wall by a fixed bracket 5.

[0181] The installation position and connection of the anemometer 14 and the heat flow meter 16 in the tunnel. Figure 8 As shown, an anemometer 14 is installed on the top of the tunnel, and an anemometer 14 is installed every 20m. The anemometer 14 is connected to the control terminal of the machine room through a wire, and the wire is fixed 0.2m to the right of the anemometer 14. The second is the installation position of the heat flow meter 16. The heat flow meter 16 is installed on the right side of the tunnel, as shown in FIG. Fig. 9As shown, it is installed on the tunnel wall 0.1m above the optical fiber deformation sensor 7. Each heat flow meter 16 transmits the signal to the control terminal in the machine room through the heat flow signal transmission wire 17. All heat flow signal transmission wires 17 are fixed to a height of 0.5m from the middle of the tunnel.

[0182] Example 3

[0183] Based on Example 1, this embodiment provides a subway tunnel thermal pollution monitoring system, including:

[0184] Data acquisition module: configured to acquire the air temperature in the tunnel and the geometric deformation data of the wall surface in the tunnel;

[0185] Thermal pollution degree judgment module: configured to perform fusion analysis and processing on the acquired air temperature data and deformation data to determine the degree of thermal pollution in the tunnel;

[0186] Control module: It is configured to control the operation mode of the heat pump unit installed in the tunnel according to the result of judging the degree of thermal pollution in the tunnel, combined with the acquired outdoor air temperature data and the heat storage amount of the air in the tunnel.

[0187] It should be noted here that the various modules in this embodiment correspond one-to-one to the various steps in Example 1, and the specific implementation process is the same, which will not be repeated here.

[0188] The above description is only a preferred embodiment of the present disclosure and is not intended to limit the present disclosure. For those skilled in the art, the present disclosure may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present disclosure shall be included in the protection scope of the present disclosure.

[0189] Although the above describes the specific implementation methods of the present disclosure in conjunction with the accompanying drawings, it is not intended to limit the scope of protection of the present disclosure. Technical personnel in the relevant field should understand that on the basis of the technical solution of the present disclosure, various modifications or variations that can be made by those skilled in the art without creative work are still within the scope of protection of the present disclosure.

Claims

1. A method for monitoring thermal pollution in a subway tunnel, characterized in that: The steps include: Obtain the air temperature in the tunnel and the geometric deformation data of the tunnel wall; The acquired air temperature data and deformation data are fused and analyzed to determine the degree of thermal pollution in the tunnel; According to the results of the judgment of the degree of thermal pollution in the tunnel, combined with the obtained outdoor air temperature data and the heat storage capacity of the air in the tunnel, the operation mode of the heat pump unit installed in the tunnel is controlled.

2. A method for monitoring thermal pollution in a subway tunnel according to claim 1, characterized in that: The method for determining thermal pollution in subway tunnels includes: Determination method of severe thermal pollution: If one of the temperature growth rate in the tunnel and the deformation rate of the inner wall of the tunnel surrounding rock exceeds the maximum value of the set threshold range, it is judged as severe thermal pollution; Method for determining moderate thermal pollution: If neither the temperature growth rate in the tunnel nor the deformation rate of the inner wall of the tunnel surrounding rock exceeds the maximum value of the set threshold range, and one of them does not exceed the set threshold range, it is judged as moderate thermal pollution; Method for determining mild thermal pollution: If the temperature growth rate in the tunnel and the deformation rate of the inner wall of the tunnel surrounding rock do not exceed the set threshold range, it is judged as mild thermal pollution.

3. A subway tunnel thermal pollution monitoring method as claimed in claim 1, characterized in that: The temperature growth rate in the tunnel is calculated as follows: the average tunnel temperature T within the set time aver The rate of change of the temperature in the tunnel relative to its initial value T0.

4. A method for monitoring thermal pollution in a subway tunnel according to claim 1, characterized in that: The deformation rate of the inner wall of the tunnel surrounding rock is calculated as follows: the maximum deformation value of the tunnel within a set time L cmax The rate of change relative to the initial tunnel wall length L0.

5. A method for monitoring thermal pollution in a subway tunnel according to claim 1, characterized in that: According to the degree of heat pollution and the amount of cold and heat stored in the tunnel, adjust the control method of the subway source heat pump unit system: If the degree of thermal pollution is severe or moderate, based on the accumulated heat storage of the monitored air in the tunnel, any of the following four control strategies is implemented to control thermal pollution: Reduce the operating power of the subway source heat pump system in the next cooling season to reduce the heat storage of the air in the tunnel; In the next heating season, increase the power of the subway source heat pump system to increase the heat intake in the tunnel; Shorten the operation time of the subway source heat pump system in the next cooling season to reduce the heat storage of the air in the tunnel; In the next heating season, the operation time of the subway source heat pump system will be extended to increase the cooling capacity of the air in the tunnel.

6. A method for monitoring thermal pollution in a subway tunnel according to claim 5, characterized in that: In the next cooling season, the operating power of the subway source heat pump system is reduced to reduce the heat storage of the air in the tunnel. The heat storage is reduced by β1 times. The calculation formula of β1 is: Where: Q x To store heat in the tunnel air until the next cooling season; c is the length of a cooling season; is the average heat flux density between the tunnel wall and air in one cooling season; Alternatively, in the next heating season, the power of the subway source heat pump system can be increased to increase the heat intake in the tunnel, and the heat storage can be increased by β2 times. The calculation formula of β2 is as follows: Where: Q x To store heat in the tunnel air until the next heating season; h is the length of a heating season; is the average heat flux density between the tunnel wall and air during the heating season; Alternatively, in the next cooling season, the operation time of the subway source heat pump system can be shortened to reduce the heat storage of the air in the tunnel. The calculation formula for the reduced time H1 is as follows: Where: Q x To store heat in the tunnel air for the next cooling season; is the average heat flux density between the tunnel wall and the air in the previous cooling season; Alternatively, in the next heating season, the operation time of the subway source heat pump system can be extended to increase the cooling capacity of the air in the tunnel. The calculation formula for the increased time H2 is as follows: Where: Q x Store heat for tunnel air; is the average heat flux density between the tunnel wall and air in the previous heating season.

7. A method for monitoring thermal pollution in a subway tunnel as claimed in claim 5, characterized in that: If the degree of thermal pollution is mild, combined with the value of the monitored accumulated heat storage of the air in the tunnel, any of the following two control strategies is implemented to control the thermal pollution: Maintain existing operational strategies; Under the condition that heat pollution does not increase, the heat intake in the heating season and the heat storage in the cooling season are dynamically adjusted to improve the efficiency of the heat pump system.

8. A method for monitoring thermal pollution in a subway tunnel according to claim 1, characterized in that: The heat storage of the air in the tunnel is the heat exchange between the tunnel wall and the tunnel air Q h 、Heat generated by heat source in tunnel Q n 、The amount of heat exchange in tunnel ventilation Q f The sum of the integrals of .

9. A subway tunnel thermal pollution monitoring system, characterized in that: It includes a control terminal, a collection device arranged in the tunnel, and a heat pump unit; The collecting device is used to collect environmental data in the tunnel, including at least the temperature in the tunnel and the geometric deformation data of the tunnel; The control terminal executes the subway tunnel thermal pollution monitoring method according to any one of claims 1 to 8 according to the data collected by the collection device, and controls the operation of the heat pump unit to achieve cold storage or heat storage.

10. A subway tunnel thermal pollution monitoring system, characterized in that: include: Data acquisition module: configured to acquire the air temperature in the tunnel and the geometric deformation data of the wall surface in the tunnel; Thermal pollution degree judgment module: configured to perform fusion analysis and processing on the acquired air temperature data and deformation data to determine the degree of thermal pollution in the tunnel; Control module: It is configured to control the operation mode of the heat pump unit installed in the tunnel according to the result of judging the degree of thermal pollution in the tunnel, combined with the acquired outdoor air temperature data and the heat storage amount of the air in the tunnel.

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