33results about How to "Meet the requirements of safe operation" patented technology

A sampling analysis system for measuring the concentration of hydrogen in the containment vessel, comprising: a sampling pipeline, a transmission pipeline, a water vapor analysis sensor, a gas pretreatment unit, a hydrogen analysis sensor, a booster pump, a microprocessor, and a display unit; The gas in the containment is extracted by the sampling pipeline with thermal insulation treatment function, and the gas is processed to normal temperature and pressure by the pretreatment unit after passing through the water vapor analysis sensor, and the hydrogen volume in the pretreated gas is measured by the hydrogen analysis sensor Concentration, the microprocessor determines the current hydrogen volume concentration in the containment according to the measurement results of the sensor and outputs and displays it. It adapts to the use requirements of common gas analysis sensors and eliminates the influence of water vapor on the gas extraction measurement method in the containment by preprocessing the measured gas and combining with the preset algorithm program in the microprocessor. It is especially suitable for accurate measurement of the volume concentration of hydrogen or other explosive gas components in the containment under accident conditions of nuclear power plants.

The invention provides a method of dynamic and variable parameter well-killing technology, belonging to the field of safe well-drilling. The method comprises the following steps: (1) obtaining basic parameters during a well-drilling process; (2) calculating formation pressure and gas cut rate according to the basic parameters; (3) configuring two well-killing fluids with different densities according to a result of the step (2) and determining volumes of well-killing fluids with different densities; (4) performing positive-cycle well-drilling operation: adopting two well-killing fluids with different densities to perform well-killing operation. During a well-killing process, casing pressure, standpipe pressure and circulating displacement are adjusted in a dynamic and real-time manner. Themethod is easy in realization and good in well killing effect and can quickly reduce the risk of excessively high well head pressure. Compared with a conventional well-killing method, the method enjoys high success rate and can meet the requirement for safe well-killing operation in a high-temperature high-pressure deep well during gas cut.

The invention relates to a method for improving the flow regime of a high velocity flow of a sharp bend section in a free-flow tunnel, and belongs to engineering methods for improving the flow regime of the high velocity flow of the sharp bend section in the free-flow tunnel. The method comprises the steps of arranging a bend stilling pool inlet slope section on a straight-line section of the tunnel, and calculating the pool depth of a stilling pool through a derived bend stilling pool computing method; enabling the gradient of the bend stilling pool inlet slope to be the same as the injection angle of the flow, arranging stairs at the lower part of the inlet slope, and enabling the width of the bend stilling pool to be the same as the width of the tunnel body; arranging a bend stilling pool outlet slope section on a downstream straight-line section, arranging a stair-type slope at the stilling pool outlet slope section, and calculating the total length of the stilling pool, wherein the stair height is 1 / 2 of the pool depth of the stilling pool optimally. According to the method, the flow regime of the high velocity flow of the sharp bend section in the free-flow tunnel is improved, and the flow regime of the high velocity flows of various bends or the flow regime of middle and low velocity flows of sharp bend sections in the free-flow tunnel can be improved the same, so that the curve layout of the free-flow tunnel is more flexible, and the method has quite good practicability and application prospect.

The invention discloses an on-line monitoring system of fatigue damage to an electric transmission line conductor by breeze vibration. The on-line monitoring system comprises a conductor vibration line monitoring device and a meteorological environment observation station, wherein the conductor vibration line monitoring device and the meteorological environment observation station are connected with the line, data collected by the conductor vibration line monitoring device and meteorological environment data monitored by the meteorological environment observation station in real time are sent to a site line monitoring communication base station through a wireless sensor network, subjected to digital processing by the site line monitoring communication base station and transmitted to a database server of a local monitoring center through a data remote transmission system, and after a data processing and analyzing system of the database server of the monitoring center analyzes on-line monitoring information, on-line data are provided for clients through the on-line monitoring information of the Internet. The system tests parameters such as environment temperatures, wind velocities and dynamic deflection strain on the breeze vibration condition of conductors and ground wires, so that the requirements of safe operation of the line can be met, and the system can guide the anti-vibration design, the breeze vibration real-time monitoring and condition-based maintenance of the transmission line.

The invention relates to a composite silicon-free defoamer for solving the problem of a foam layer in a coke tower. The technical scheme of the composite silicon-free defoamer is that the defoamer isprepared from the following materials in parts by weight: 20-50 parts of lauryl alcohol, 10-50 parts of polyoxyethylene polyoxypropylene glycerol ether, 5-20 parts of phenol derivative ethoxy propoxylate and 10-30 parts of isooctanol. The invention is free of silicon, nontoxic and harmless, excellent in heat resistance, and is not decomposed when heated to 500 DEG C and is suitable for defoaming at high temperature. The defoaming effect of silicon-free defoamer is equivalent to that of low-silicon defoamers, and better than high-silicon defoamers; and the defoamed ratio can reach 90% or more when the added quantity exceeds 50 gamma / g. The site trial shows that the product has excellent defoaming effect, and satisfies the requirements of safe operation of devices without any undesirable effects for the product quality and catalysts of a downstream unit through inspection.

The invention relates to the technical field of electric vehicles, particularly discloses an electric vehicle charging station planning method based on a gravitation search algorithm. The electric vehicle charging station planning method based on the gravitation search algorithm comprises the steps of obtaining the related information of a planning area, wherein the related information comprises the planning area traffic network information, the planning area power distribution network informatization and the electric vehicle driving range information; estimating the range of the number of charging stations in the planned area; calculating the whole social cost of all charging stations in the planned area according to a gravitation search algorithm; comparing all the social costs of all the charging stations to obtain a planning scheme corresponding to the lowest cost. According to the electric vehicle charging station planning method based on the gravitational search algorithm, the charging station can be reasonably planned in a city with insufficient land, the requirement for safe operation of a power distribution network is met, and the rapid and convenient charging service canbe provided for vehicles.

The invention provides a system for detecting transmission tower and line based on point cloud data, comprising an unmanned aerial vehicle acquisition system, wherein the unmanned aerial vehicle acquisition system is equipped with an AS-100. Based on the point cloud trajectory captured by UAV during flight, the point cloud map of transmission tower and line is constructed according to the point cloud trajectory, and the video data is collected by UAV during flight. A point cloud preprocessing device preprocesses the acquired point cloud data to obtain the ground laser point cloud, the vegetation laser point cloud and the transmission line laser point cloud data respectively; The statistical analysis module optimizes the transmission tower location based on the section, and carries out statistical analysis on the line indexes according to the coordinate data of transmission tower location and the section data of transmission tower foundation; Three-dimensional modeling module, by processing the point cloud data and video data collected by the unmanned aerial vehicle (UAV) mounted system to generate quasi-DOM, DEM, combined with the classified point cloud, to achieve the three-dimensional modeling of transmission tower and transmission line.

The invention relates to a frequency modulation and electric energy combined clearing method, device and apparatus in the power market, and belongs to the technical field of power system dispatching operation. The method comprises the following steps: acquiring boundary data required by electric power spot market transaction and standby auxiliary service arrangement; obtaining declaration data ofmarket members; according to the boundary data and the declaration data, enabling the electric energy and frequency modulation auxiliary service combined clearing model based on the reserve capacity constraint to perform combined clearing on the electric energy and frequency modulation auxiliary service; and optimizing the standby auxiliary service based on the optimized standby auxiliary servicemodel according to a combined clearing result of the electric energy and the frequency modulation auxiliary service. An electric energy and frequency modulation auxiliary service combined clearing model considering standby capacity constraints is utilized. Standby capacity constraints are considered in combined clearing of electric energy and frequency modulation auxiliary services. The problem that in the prior art, a summarized power generation resource decision-making mechanism is not coordinated is solved, electric energy, frequency modulation and standby operation plans of a generator setmeet the requirement for safe operation of a power grid, and the safety of power grid dispatching operation is guaranteed.

The invention discloses a working vehicle for overhauling large span transmission lines, and the vehicle comprises a working cage, a main wheel frame horizontally mounted on the top of the working cage, and main pulleys movably mounted on the main wheel frame. The length of the main wheel frame is greater than that of the working cage. The main pulleys are mounted at two ends of the main wheel frame respectively. The working cage is also articulated with an auxiliary wheel frame. The two ends of the auxiliary wheel frame top are respectively provided with auxiliary pulleys, and the bottom is equipped with a handle. The handle can rotate the auxiliary wheel frame around the hinge shaft to change the cooperation between the main pulleys and the cable. The invention has the beneficial effects that the working cage is directly connected fixedly with the main wheel frame so as to reduce the shaking problem existing in the working process. And the main wheel frame has a longer size, which further enhances the stability in the direction of travel to avoid overturning. With the manually rotating auxiliary wheel frame, the contact between the main pulleys and the cable can be changed for barrier-free pass.

The invention provides a butterfly valve of an intermediate-pressure cylinder of a steam turbine. The butterfly valve is used for adjusting the flow of steam entering a low-pressure cylinder. The butterfly valve of the intermediate-pressure cylinder of the steam turbine is arranged on an outlet of the intermediate-pressure cylinder. The butterfly valve mainly comprises a valve body, a valve clack,a rotating shaft and electric execution mechanisms, and is mainly characterized in that two small valve clacks are mounted on the sealing face of the valve clack; gaps matched with the small valve clacks are formed at the positions, corresponding to the mounting positions of the small valve clacks, on the valve clack, and a rotating clearance is reserved; the two small valve clacks are symmetrically mounted at the positions, on the two sides of the rotating shaft of the valve body, and rotating shafts of the two small valve clacks are perpendicular to the rotating shaft and are guided out from the valve body; and the small valve clacks are used for slightly adjusting the steam flow. The butterfly valve can be used for adjusting the quantity of steam entering the low-pressure cylinder, therequirement of safe operating of the low-pressure cylinder can be met, extracted steam is utilized for heat supply to the largest degree, and the advantages of saving occupied land, saving investments and the like are achieved.

The invention discloses an oil-water separating sewage drain device for a transformer oil reservoir. The device is characterized by being composed of an oil reservoir water level determination device (1), an integrated control device (2) and a sewage drain device (3); the oil reservoir water level determination device (1) comprises a supporting rod substrate (1-10), an adjustable supporting rod (1-2), a zero potential contact chip (1-1), a sewage drain pump start contact chip (1-3), and a sewage drain pump stop contact chip (1-4); the integrated control device (2) comprises a control device body (2-13), a power switch (2-6), a liquid crystal display (2-5), and an F21-E1RX remote control device (2-14); the sewage drain device (3) comprises a sewage drain pump (3-1) and a voltage-sensitive relay CJXZ-2510 (3-2). According to the oil-water separating sewage drain device for the transformer oil reservoir, water in the transformer oil reservoir is monitored in real time and drained in time, therefore, the occurrence of an accident that the surrounding environment is damaged due to occurrence of overflow of transformer oil when the oil reservoir is waterlogged is prevented, and the labor intensity of operation and maintenance staff as well as operation and maintenance cost of the device are reduced.

The invention discloses a water flow situation estimation method for an urban underground drainage pipe network. Various complex factors bring great difficulties to water flow situation estimation ofan urban underground drainage system. The method comprises the steps of firstly establishing a state space model of a water flow situation estimation system of the urban underground drainage pipe network, then constructing an estimator model of the water flow situation of the underground drainage pipe network, solving a water flow situation estimator of the urban underground drainage pipe networksystem, and obtaining a gain matrix of the estimator. According to the method, the underground drainage pipe network is described by using a state saturation complex network; meanwhile, a random timedelay effect in measurement data transmission is considered; through finite time mean square boundness and interference suppression performance analysis of a drainage pipe network water flow situationestimation system, a linear matrix inequality method is used for solving an estimator, timely and accurate estimation of the urban underground drainage pipe network water flow situation is achieved,and the actual safe operation requirement of an underground drainage system is met.

An elevator emergency lighting system comprises a control chip, a lift car lighting source fault detection circuit module, a mains supply power failure detection circuit and a battery voltage and battery charging detection circuit. The lift car lighting source fault detection circuit module at least comprises an LED lighting lamp constant-current drive circuit and a lift car illumination detectioncircuit, and the lift car illumination detection circuit is used for collecting the illumination in a lift car, converting the illumination into an illumination signal which can be recognized by thecontrol chip, and judging whether a standby LED light source is started by driving the LED illuminating lamp constant-current driving circuit or not according to the collected illumination intensity.Aiming at the fault of a lift car lighting source, the standby light source can still be automatically started through the system, and alarm processing is carried out. According to the present invention, the problem that the working time of emergency lighting cannot be verified during existing maintenance can be effectively solved, the fault type of an emergency power supply can be automatically identified, the overall emergency power supply replacement cost is greatly saved, the maintenance efficiency is improved, and the energy conservation and environmental protection are achieved.

The invention provides an erection method and an erection system of an overhead conductor considering creep quantity. The method comprises the steps of determining a creep characteristic of the conductor by different temperature conductor creep tests to obtain an equivalent time conductor hardening creep rate equation, respectively calculating creep quantity in an operation process of the conductor and creep quantity in an operation process of the conductor based on the creep equation to obtain creep quantity in a tensile pay-off process of the conductor and the creep quantity in the operationprocess of the conductor, and performing overhead line conductor erection based on the creep quantity in the tensile pay-off process of the conductor and the creep quantity in the operation process of the conductor. With the adoption of the method and the system, the overhead conductor can be well erected, and a safe operation requirement is met.

The invention provides a method for detecting transmission tower and transmission line based on point cloud data. The method comprises following steps: an unmanned aerial vehicle carrying system is provided, wherein the unmanned aerial vehicle carrying system is an unmanned aerial vehicle carrying an AS-100 Laser Lidar system; based on the point cloud trajectory captured by the UAV during flight,the point cloud map along the transmission tower and line is constructed according to the point cloud trajectory, and the video data is collected by UAV during flight; the data of ground laser point cloud, vegetation laser point cloud and transmission line laser point cloud are obtained by pre-processing the collected data of point cloud; the transmission tower location is optimized based on the profile, and the transmission tower location coordinate data and the transmission tower foundation cross-section data are used to analyze the transmission line indicators. By processing the point clouddata and video data collected by the UAV system, the quasi-DOM and DEM are generated. Combined with the classified point cloud, the three-dimensional modeling of transmission towers and transmissionlines is realized.

The invention relates to a non-active pressure-boosting pressure-stabilizing system capable of alleviating cavitation abrasion of a water lubricated main-pump bearing. According to the system, a conventional openmouthed main pump head box is changed into a sealed head box, also two electric stop valves are additionally installed on an exhaust overflow pipe, and an exhaust valve is additionally installed at the upper part of the head box. Because of a pressure stabilizing system consisting of a throttling member, an inverted valve and a pressure-stabilizing tank, the influence of pressure fluctuation of a desalted water supply system to the head box is buffered; an inflation system of the pressure-stabilizing tank is formed by utilizing a conventional nitrogen low-pressure system and additionally installing a manual stop valve used for adjusting nitrogen pressure and a manual stop valve used for closing and stopping nitrogen supply; by opening the electric stop valve in parallel connection with the inverted valve and opening the exhaust valve at the exhaust overflow pipe of the main pump head box and closing the electric stop valve at the inlet pipe of the pressure-stabilizing tank, the connection between changed return part and the original system is rapidly cut off; and by opening the manual stop valve used for closing and stopping nitrogen supply and at an air inflation pipe of the pressure-stabilizing tank, air can be supplied when a reactor is operated.

The invention provides a temperature control circuit of a variable frequency heat pump driver. The temperature control circuit is used for controlling outputting of variable frequency heat pump driverdevices at a high temperature. The temperature control circuit comprises a first temperature detection unit, a second temperature detection unit and a main control chip. The first temperature detection unit is used for reading the temperature of an inverter bridge circuit in real time. The second temperature detection unit is used for reading the temperature of a rectifier bridge circuit and thetemperature of a power-factor correction circuit in real time. The main control chip is used for controlling outputting of the variable frequency heat pump driver according to the temperature read bythe first temperature detection unit and the temperature read by the second temperature detection unit. By adoption of the temperature control circuit of the variable frequency heat pump driver, destroying and damaging probability of the variable frequency heat pump driver devices at the high temperature is effectively reduced, the characteristics of prolonging the service life of the complete machine of the driver and reducing the failure rate of the complete machine are achieved, and the user experience of electronic heating products is improved.

A method for controlling the smoke dust of lime kiln features that a dust collecting hood is used to capture smoke dust, a duster is then used for separating dust from fume, and the fume is finally exhausted. The frequency-variable control is applied to said duster, so its blower can be connected to DCS system for automatic regulation.

The invention discloses a method for improving the heat primary air temperature of a boiler with high moisture coal burned. Walls on the two sides of a rear smoke channel in the area of a low temperature reheater or a low temperature superheater of the boiler are respectively provided with an opening. A hot flue gas leading-out pipe is installed at the openings and is led to an inlet of a primary air pre-heater. Due to the fact that the pressure of an inlet and the pressure of an outlet of the hot flue gas leading-out pipe are different, the produced pressure difference drives hot flue gas to flow into the primary air pre-heater via the hot flue gas leading-out pipe from the area of the low temperature reheater or the low temperature superheater of the boiler, and the heat primary air temperature, the grinding inlet temperature and the grinding outlet temperature are improved remarkably. By means of the method, when the high moisture coal is applied to the power station boiler, the heat primary air temperature, the grinding inlet temperature and the grinding outlet temperature are improved, the requirement for safety operation of a coal mill can be met, meanwhile, a steam-water system of the boiler is normal, discharging of NOx is normal, the safety operation of the boiler is improved, the structure of a device is reasonable, investment is small, operation cost is low, and the method is suitable for the situation of China.

The invention relates to a composite silicon-free defoamer for solving the problem of a foam layer in a coke tower. The technical scheme of the composite silicon-free defoamer is that the defoamer is prepared from the following materials in parts by weight: 20-50 parts of lauryl alcohol, 10-50 parts of polyoxyethylene polyoxypropylene glycerol ether, 5-20 parts of phenol derivative ethoxy propoxylate and 10-30 parts of isooctanol. The invention is free of silicon, nontoxic and harmless, excellent in heat resistance, and is not decomposed when heated to 500 DEG C and is suitable for defoaming at high temperature. The defoaming effect of silicon-free defoamer is equivalent to that of low-silicon defoamers, and better than high-silicon defoamers; and the defoamed ratio can reach 90% or more when the added quantity exceeds 50 gamma / g. The site trial shows that the product has excellent defoaming effect, and satisfies the requirements of safe operation of devices without any undesirable effects for the product quality and catalysts of a downstream unit through inspection.

The invention discloses a wide-load denitration system of heating flue gas by fuel gas supplementary combustion based on boiler deep peak regulation. The system comprises a fuel gas combustor, an economizer outlet horizontal flue and a denitration reactor, wherein the economizer outlet horizontal flue communicates with the denitration reactor, the gas burner is arranged on the horizontal section of the economizer outlet flue; and the gas burner internally comprises a gas burner primary air pipe and a gas burner secondary air pipe. The system is reasonable in design and simple in structure andcapable of flexibly and conveniently adjusting the temperature level of an inlet of the denitration reactor according to actual requirements, thus achieving the purposes of uniform distribution of a temperature field and a speed field behind a rectification grid of the denitration reactor, and has the characteristics of simple and convenient installation engineering and flexible arrangement of construction, so that the problem that the flue gas temperature for wide-load denitration is insufficient is fundamentally solved.

The invention discloses a three-phase split transformer insulation monitoring signal centralized sampling device. The device is composed of a centralized sleeve end screen current signal sampling unit, a centralized reference voltage signal sampling current, an intelligent sink control cabinet, three-phase split transformer sleeve current signals and three-phase split transformer sleeve voltage signals. The device has the advantages that online monitoring signals of sleeves of one transformer can be acquired in a centralized mode, the number of reference sensors is greatly reduced, and therefore measurement errors caused by the sensors are reduced; as is shown in detection, all technical indexes of the device meet the requirement for safe operation of the sleeves of the transformer; the configuration mode is simple, technicians can install, adjust, check and maintain the device conveniently, and the device is easy to apply and popularize.

The invention discloses a working vehicle for overhauling large span transmission lines, and the vehicle comprises a working cage, a main wheel frame horizontally mounted on the top of the working cage, and main pulleys movably mounted on the main wheel frame. The length of the main wheel frame is greater than that of the working cage. The main pulleys are mounted at two ends of the main wheel frame respectively. The working cage is also articulated with an auxiliary wheel frame. The two ends of the auxiliary wheel frame top are respectively provided with auxiliary pulleys, and the bottom is equipped with a handle. The handle can rotate the auxiliary wheel frame around the hinge shaft to change the cooperation between the main pulleys and the cable. The invention has the beneficial effects that the working cage is directly connected fixedly with the main wheel frame so as to reduce the shaking problem existing in the working process. And the main wheel frame has a longer size, which further enhances the stability in the direction of travel to avoid overturning. With the manually rotating auxiliary wheel frame, the contact between the main pulleys and the cable can be changed for barrier-free pass.

The invention provides a small-diameter tube inner wall detection probe assembly. The small-diameter tube inner wall detection probe assembly comprises a connecting tube, wherein one end of the connecting tube is connected with an automatic mechanical device through a flange, and the other end of the connecting tube is connected with a frame body through at least one coupling; the frame body is provided with a plurality of elastic pressing arms along the circumferential direction; the elastic pressing arms comprise connecting ends connected with the frame body and protruding ends protruding outwards along the radial direction of the frame body; the protruding ends of the elastic pressing arms can elastically displace towards the frame body under the action of external force; the elastic pressing arms are provided with probe mounting blocks for mounting detection probes; the probe mounting blocks are provided with protruding parts protruding to one side, away from the frame body, of each of the elastic pressing arms. The small-diameter tube inner wall detection probe assembly has the advantages of easiness in operation, good alignment, good probe coupling effect and the like, can effectively solve the problem of implementing lossless detection of a weld joint of a top cover instrument connecting tube of a reactor pressure vessel from interior and meets the requirement of safety operation of nuclear power.

The invention discloses an oil-water separating sewage drain device for a transformer oil reservoir. The device is characterized by being composed of an oil reservoir water level determination device (1), an integrated control device (2) and a sewage drain device (3); the oil reservoir water level determination device (1) comprises a supporting rod substrate (1-10), an adjustable supporting rod (1-2), a zero potential contact chip (1-1), a sewage drain pump start contact chip (1-3), and a sewage drain pump stop contact chip (1-4); the integrated control device (2) comprises a control device body (2-13), a power switch (2-6), a liquid crystal display (2-5), and an F21-E1RX remote control device (2-14); the sewage drain device (3) comprises a sewage drain pump (3-1) and a voltage-sensitive relay CJXZ-2510 (3-2). According to the oil-water separating sewage drain device for the transformer oil reservoir, water in the transformer oil reservoir is monitored in real time and drained in time, therefore, the occurrence of an accident that the surrounding environment is damaged due to occurrence of overflow of transformer oil when the oil reservoir is waterlogged is prevented, and the labor intensity of operation and maintenance staff as well as operation and maintenance cost of the device are reduced.

The invention relates to a welding-type jockey pulley base of a stainless steel escalator step, belonging to the manufacturing field of escalators. The traditional structure is formed by casting integrally and has the problems of energy consumption, low percent of pass, high manufacturing cost and poor consistency. The welding-type jockey pulley base of the stainless steel escalator step comprises a jockey pulley shaft and a base body with a mounting hole, wherein the jockey pulley shaft and the base body are detachable members which are integrally welded and fixed; the jockey pulley shaft iscylindrical and comprises a jockey pulley mounting part on the upper part, a shaft lever in the middle part and a shaft base connection end on the lower part; the base body is a board stamping part comprising a triangular bottom face and a side wall which is perpendicular to the bottom face and provided with an opening at one end; a connection chamfer is arranged at the joint of the triangular bottom face and the side wall; and the vertex angle of the triangular bottom face is provided with a jockey pulley mounting hole in which the jockey pulley mounting part is inserted. The invention has the advantages of detachable production, convenient processing, low manufacturing cost, energy saving, light self weight and good strength, and is suitable for detachable-type stainless steel steps.

The invention relates to a method for improving the flow regime of a high velocity flow of a sharp bend section in a free-flow tunnel, and belongs to engineering methods for improving the flow regime of the high velocity flow of the sharp bend section in the free-flow tunnel. The method comprises the steps of arranging a bend stilling pool inlet slope section on a straight-line section of the tunnel, and calculating the pool depth of a stilling pool through a derived bend stilling pool computing method; enabling the gradient of the bend stilling pool inlet slope to be the same as the injection angle of the flow, arranging stairs at the lower part of the inlet slope, and enabling the width of the bend stilling pool to be the same as the width of the tunnel body; arranging a bend stilling pool outlet slope section on a downstream straight-line section, arranging a stair-type slope at the stilling pool outlet slope section, and calculating the total length of the stilling pool, wherein the stair height is 1 / 2 of the pool depth of the stilling pool optimally. According to the method, the flow regime of the high velocity flow of the sharp bend section in the free-flow tunnel is improved, and the flow regime of the high velocity flows of various bends or the flow regime of middle and low velocity flows of sharp bend sections in the free-flow tunnel can be improved the same, so that the curve layout of the free-flow tunnel is more flexible, and the method has quite good practicability and application prospect.