Method for guaranteeing aerodynamic braking satisfies emergency braking safety

Abstract

Disclosed is a method for guaranteeing aerodynamic braking satisfies emergency braking safety, comprising: step S1: performing computation by means of fluid simulation software to acquire a wind load borne by an aerodynamic braking apparatus, separately performing static strength simulation, fatigue strength simulation, and impact strength simulation, and, on the basis of simulation results, optimizing the structure of the aerodynamic braking apparatus; and step S2: designing the means of opening and the shape of braking wings of the aerodynamic braking apparatus, and designing the means of arranging the braking wings on a train; by means of the fluid simulation software, performing simulation and analysis on the train on which the aerodynamic braking apparatus is mounted, and, on the basis of a simulation result, performing optimization on the means of opening and the shape of the braking wings and the means of arranging the braking wings on the train. According to the present invention, optimization of the structure of the aerodynamic braking apparatus is achieved, and further, the optimization of the means of opening, the shape, and the means of arranging the braking wings mounted on the train is achieved, so that the safety of aerodynamic braking is improved.

Description

A method for ensuring the safety of wind resistance braking in emergency braking

[0001] This application claims priority to the Chinese patent application filed with the Patent Office of China on January 26, 2024, with application number 202410114396.6 and invention name “Method for ensuring wind resistance braking meets emergency braking safety requirements”, the entire contents of which are incorporated by reference into this application. Technical Field

[0002] The present invention relates to the technical field of windage braking, and in particular to a method for ensuring that windage braking meets the safety requirements of emergency braking. Background Art

[0003] Windage braking is a non-adhesive braking method that slows or stops high-speed trains by increasing air resistance. It is often used on trains running at higher speeds.

[0004] Windage brakes are typically placed on the surface of a vehicle to effectively block airflow and brake the vehicle during operation. They can be retracted into the vehicle to meet train clearance requirements. When a train is traveling at high speeds, air resistance is a significant factor hindering its motion. Windage brakes increase the cross-sectional area of ​​the train, thereby increasing windage resistance, thereby slowing the train and stopping it. This can significantly reduce the distance required for a high-speed train to stop.

[0005] During adhesion braking, the adhesion coefficient decreases as train speed increases. This poses a significant risk when the train's initial velocity is high and emergency braking is used. Currently, windage braking systems are still in the experimental stage, and research on windage braking's ability to meet braking safety requirements is limited.

[0006] Summary of the Invention

[0007] In view of this, an object of the present invention is to provide a method for ensuring the safety of windage braking in an emergency situation, thereby improving the safety of windage braking.

[0008] In order to achieve the above object, the present invention provides the following solutions:

[0009] A method for ensuring windage braking meets emergency braking safety requirements, comprising:

[0010] Step S1: Calculating the wind load carried by the wind resistance brake device using fluid simulation software, and performing static strength simulation, fatigue strength simulation, and impact strength simulation respectively, and optimizing the structure of the wind resistance brake device according to the simulation results;

[0011] Step S2: Designing the opening method and appearance of the brake vanes of the wind resistance brake device, and designing the method for disposing the brake vanes on the train. Using fluid simulation software, simulate and analyze the train equipped with the wind resistance brake device. Based on the simulation results, optimize the opening method, appearance, and arrangement of the brake vanes on the train.

[0012] In a specific embodiment, the step S1 of calculating and obtaining the wind load borne by the windage braking device using fluid simulation software specifically includes:

[0013] Determining a three-dimensional model and a computational domain of the windage brake device, and dividing the three-dimensional model of the device into grids;

[0014] The k-ε two-equation turbulence model is selected, and after calculation and data post-processing, the pressure cloud map of the six-degree-of-freedom aerodynamic force is obtained.

[0015] In another specific embodiment, the static strength simulation in step S1 specifically includes: using the six-degree-of-freedom aerodynamic force as the braking wing load of the wind resistance brake device to obtain the equivalent stress σ of each component of the wind resistance brake device 等效 Cloud chart, check whether the components of the windage brake device meet the material strength requirements, Where: σ1 is the maximum principal stress; σ2 is the intermediate principal stress; σ3 is the minimum principal stress;

[0016] The fatigue strength simulation in step S1 specifically includes: importing a three-dimensional model of the wind resistance brake device, using the six-degree-of-freedom pressure as the brake vane load, setting the time series to white noise, and obtaining a fatigue life cloud map and a fatigue damage cloud map of the wind resistance brake device to determine the service life and safety of the wind resistance brake device;

[0017] The fatigue impact strength simulation in step S1 specifically includes: importing a three-dimensional model of the wind resistance brake device and a three-dimensional model of the bird body, setting the constraint relationship and material properties of the wind resistance brake device, setting the three-dimensional model of the bird body to water material, using the train speed as the initial velocity of the bird body, obtaining the equivalent stress distribution and strain distribution of the wind resistance brake device under the impact of the bird body, determining the safety of the wind resistance brake device under the impact of foreign objects, and simultaneously finding the position of the wind resistance brake device to be strengthened based on the equivalent stress distribution and strain distribution.

[0018] In another specific embodiment, step S3 is further included between step S1 and step S2:

[0019] Using a wind load test bench to conduct static strength and fatigue strength tests on the wind resistance brake device;

[0020] Performing an impact strength test on the windage brake device on a bird strike test device;

[0021] The structure of the windage brake device is optimized at locations where stress concentration and strain exceed preset values, and the corresponding component materials are optimized and selected.

[0022] In another specific embodiment, the method of designing the arrangement of the brake vanes on the train in step S2 specifically includes:

[0023] The installation angle of the brake wing on the train is designed so that the aerodynamic drag generated by the brake wing is greater than a preset drag value and the aerodynamic lift generated is zero;

[0024] In combination with the train body structure, with the goal of ensuring that the aerodynamic drag provided by the train's windage brake is greater than a preset drag value, an orthogonal test method is used to determine the installation position of the windage brake device on the train, the lateral and longitudinal spacing between adjacent brake vanes, and the number of brake vanes.

[0025] The six-degree-of-freedom braking force generated by the wind resistance braking device on the train is used to control the running stability of the train and the vehicle track departure rate C. 脱轨 , Wheel weight variation coefficient C 轮重变化 The installation method of the wind resistance braking device on the train is designed based on the influence of wind resistance braking device.

[0026] In another specific embodiment, the vehicle track departure rate C 脱轨 : The wheel weight variation coefficient C 轮重变化 :

[0027] Where: F 横 F is the lateral force on the wheels of the train; 垂 F is the vertical force on the wheel; 垂差 F is the difference between the maximum and minimum vertical forces acting on the wheel; 垂均 is the average lateral force acting on the wheel.

[0028] In another specific embodiment, the simulation analysis of the train equipped with the wind resistance brake device by fluid simulation software in step S2 specifically includes: using fluid mechanics calculation software to calculate the aerodynamic load of the train equipped with the wind resistance brake device under crosswind conditions, intersection conditions and tunnel conditions, and evaluating the impact on the safety of the train operation.

[0029] In another specific embodiment, when designing the brake wing of the wind resistance brake device in step S2, a locking mechanism needs to be provided on the brake wing so that the brake wing can be locked when the brake wing is opened to a preset angle.

[0030] In another specific embodiment, before step S1, after step S2, or between step S1 and step S2, step S4 is further included: adjusting the control system corresponding to the windage braking device so that the control system meets the preset failure rate requirement.

[0031] In another specific embodiment, step S4 specifically includes:

[0032] Step S41: sort out and summarize all faults to obtain various fault modes;

[0033] Step S42: Determine the fault impacts caused by different fault modes and list them;

[0034] Step S43: determining the top event of the fault tree based on the list and the severity level, and analyzing the working mechanism of the fault component to determine each sub-fault component to construct the fault tree;

[0035] Step S44: Use the minimum cut set method to perform qualitative analysis on the fault tree to obtain each minimum cut set A i ;

[0036] Step S45: Use the cut set probability summation method to quantitatively calculate the fault tree, solve the failure rate of each minimum cut set and sum them to obtain the top event failure rate R 顶 :

[0037] Where: n is the number of minimum cut sets, R(A i ) is the failure rate of the i-th minimum cut set;

[0038] Step S46: The top event failure rate R 顶 The control system and the fault tree are optimized by comparing the result with the preset failure rate requirement.

[0039] The various embodiments according to the present invention can be arbitrarily combined as needed. The embodiments obtained after these combinations are also within the scope of the present invention and are part of the specific implementation methods of the present invention.

[0040] The windage brake provided by the present invention meets the safety requirements of emergency braking. Using fluid simulation software, the windage brake device undergoes static strength, fatigue strength, and impact strength simulations. Based on the simulation results, the windage brake device's structure is optimized. Simulating the optimized windage brake device's placement on a train optimizes the brake vane's deployment and appearance based on the simulation results, as well as its placement on the train. This optimizes the windage brake device's structure and the deployment, appearance, and placement of the brake vanes when mounted on the train, thereby improving windage brake safety. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] 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 these drawings without paying any creative work.

[0042] FIG1 is a flow chart of a method for ensuring the safety of windage braking in emergency braking provided by the present invention. DETAILED DESCRIPTION

[0043] The following will be combined with Figure 1 of the embodiment of the present invention to clearly and completely describe the technical solutions in the embodiment of the present invention. Obviously, the embodiment described is only a part of the embodiment of the present invention, not all the embodiments. Based on the embodiment of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0044] As shown in FIG1 , the present invention provides a method for ensuring the safety of windage braking in emergency braking, so as to improve the safety of windage braking.

[0045] Specifically, windage braking meets the emergency braking safety guarantee method including:

[0046] Step S1: The wind load borne by the wind resistance brake device is obtained by calculating using fluid simulation software, and static strength simulation, fatigue strength simulation and impact strength simulation are performed respectively, and the structure of the wind resistance brake device is optimized according to the simulation results.

[0047] The wind load borne by the wind resistance brake device is obtained by calculating with fluid simulation software, which specifically includes: determining the three-dimensional model and calculation domain of the wind resistance brake device, and dividing the three-dimensional model of the device into grids; selecting the k-ε two-equation turbulence model, and obtaining the pressure cloud map of the six-degree-of-freedom aerodynamic force through data post-processing after calculation.

[0048] Fluid simulation software can be Fluent or other software capable of fluid simulation. It should be noted that in the k-ε two-equation turbulence model, k represents the turbulent kinetic energy and ε represents the dissipation rate. It should also be noted that the six degrees of freedom in the six-degree-of-freedom aerodynamic pressure contour map represent the drag, lateral force, lift, rolling moment, longitudinal oscillation moment, and oscillation moment experienced by the windage brake.

[0049] The static strength simulation specifically includes: taking the six-degree-of-freedom aerodynamic force as the brake wing load of the wind resistance brake device, and obtaining the equivalent stress σ of each component of the wind resistance brake device 等效 Cloud chart, check whether the components of the windage brake device meet the material strength requirements.

[0050] in, Where: σ1 is the maximum principal stress; σ2 is the intermediate principal stress; σ3 is the minimum principal stress.

[0051] Fatigue strength simulation involves long-term cyclic load testing to simulate the fatigue life of the windage brake under actual operating conditions. This includes importing a 3D model of the windage brake, applying six-degree-of-freedom pressure as the brake vane load, and configuring the time series as white noise. This generates fatigue life and fatigue damage cloud maps to determine the windage brake's service life and safety.

[0052] Because the windage brake system is also subject to impacts from flying birds and other objects, it is necessary to test its load-bearing capacity in the event of an accident to simulate impact loads of different directions and intensities. The fatigue impact strength simulation specifically involves importing a 3D model of the windage brake system and a 3D model of the bird, setting the constraints and material properties of the windage brake system, and setting the 3D bird model to a water material. The train speed is used as the initial velocity of the bird, and the equivalent stress and strain distribution of the windage brake system under bird impact is obtained to determine the safety of the windage brake system under impact from foreign objects. Based on the equivalent stress and strain distributions, the locations of the windage brake system that need to be strengthened are identified.

[0053] It can be understood that the position to be strengthened in the wind resistance brake device refers to the weak position in the wind resistance brake device. The weak position can be solved by increasing the thickness or increasing the strength of the material.

[0054] Step S2: Design the opening method and appearance of the brake vanes of the wind resistance brake device, and design the method for arranging the brake vanes on the train. Use fluid simulation software to simulate and analyze the train equipped with the wind resistance brake device. Based on the simulation results, optimize the opening method, appearance, and arrangement of the brake vanes on the train.

[0055] When designing the brake vane's deployment method and shape, it's important to ensure the vane fits within the train's installation space and complies with the train's bidirectional operation characteristics. Specifically, the vane's deployment method and shape are designed to maximize aerodynamic drag on a single vane, taking into account the train's structural characteristics.

[0056] The specific method of designing the arrangement of brake wings on the train includes: designing the installation angle of the brake wings on the train so that the aerodynamic drag generated by the brake wings is greater than the preset drag value and the aerodynamic lift generated is zero; combining the body structure of the train, with the goal of the aerodynamic drag provided by the train's wind resistance braking being greater than the preset drag value, using the orthogonal test method to obtain the installation position of the wind resistance braking device on the train, the lateral spacing and longitudinal spacing between adjacent brake wings, and determining the number of brake wings; based on the six-degree-of-freedom braking force generated by the wind resistance braking device on the train, the train running smoothness and vehicle track departure rate C are evaluated. 脱轨 , Wheel weight variation coefficient C 轮重变化 Considering the influence of wind resistance, design the installation method of wind resistance braking device on the train.

[0057] It should be noted that the preset drag value is set based on specific needs. Specifically, the aerodynamic drag generated by the braking airfoil must be greater than the preset drag value while ensuring that the aerodynamic drag generated by the braking airfoil is as large as possible. Because the aerodynamic lift generated by aerodynamic drag is not positive lift, the aerodynamic lift generated by aerodynamic drag should be close to zero.

[0058] Specifically, the installation angle of the dynamic air blades on the train is greater than or equal to 75 degrees and less than or equal to 85 degrees. The ratio of the longitudinal spacing of the braking air blades to the height of the braking air blades is 10-15.

[0059] Vehicle track departure rate C 脱轨 : Wheel weight variation coefficient C 轮重变化 : Where: F 横 is the lateral force on the wheels of the train; F 垂 is the vertical force acting on the wheel; F 垂差 The difference between the maximum and minimum vertical forces acting on the wheel; F 垂均 is the average lateral force acting on the wheel.

[0060] The simulation analysis of trains equipped with wind resistance brakes using fluid simulation software specifically includes: using fluid mechanics calculation software to calculate the aerodynamic loads on trains equipped with wind resistance brakes under crosswind conditions, crossing conditions, and tunnel conditions, and evaluating the impact on train operation safety.

[0061] When simulating crosswind conditions, crosswind is applied as an inlet boundary condition. When simulating crossing and tunneling conditions, the computational domain mesh should be constructed using a sliding mesh. A dynamics model of a train with a windage brake was established using the dynamics simulation analysis software Simpack. The resulting aerodynamic loads were applied to the windage brake and the train, and train dynamics parameters such as the derailment coefficient, axle load reduction ratio, and overturning moment coefficient were calculated at maximum operating speed. By analyzing the train dynamics parameters for each condition, the impact on train operational safety was assessed.

[0062] Based on the simulation results, the opening method, shape and arrangement of the brake vanes on the train are optimized. Specifically, considering the simulation results of aerodynamics and vehicle dynamics, the shape, installation position, installation quantity, installation spacing, opening method, etc. of the brake vanes of the windage braking device are optimized and improved to ensure the safety of train operation during emergency braking of the windage braking device.

[0063] The present invention optimizes the structure of the wind resistance braking device and optimizes the opening method, appearance and arrangement of the brake vanes when installed on the train, thereby improving the safety of the wind resistance braking.

[0064] In some embodiments, when designing the brake blades of the wind resistance brake device in step S2, a locking mechanism is also required to be provided on the brake blades so that the brake blades can be locked when they are opened to a preset angle.

[0065] It should be noted that the preset angle is set according to specific needs and is not limited to one or certain specific values.

[0066] The setting of the locking mechanism can ensure that the brake fan is locked after opening to a certain angle and cannot be further opened to a larger angle or a smaller angle, so that it can ensure the stability of the opening angle of the brake fan, that is, the stable braking force output in the event of a power source failure.

[0067] In the present invention, the windage braking device is not affected by the train power source factors, preventing windage braking emergency braking failure caused by power source failure, improving the reliability and stability of braking, and providing safer protection during the train braking process.

[0068] In some embodiments, step S3 is further included between step S1 and step S2: using a wind load test bench to perform static strength and fatigue strength tests on the wind resistance brake device; performing an impact strength test on the wind resistance brake device on a bird strike test device; performing structural optimization on locations where stress concentration and strain of the wind resistance brake device exceed preset values, and optimizing the selection of corresponding component materials.

[0069] The static strength test is to test the performance and strength of the wind resistance brake device under static load. The wind speed at the outlet of the wind load test bench is a fixed value, which can be the maximum operating speed of the train.

[0070] The fatigue strength test is to test the performance and strength of the wind resistance brake device under the action of alternating loads. The wind speed at the outlet of the wind load test bench is an alternating wind speed, which can be a sine or step function.

[0071] The impact strength test can use a live chicken weighing about 1 kg to simulate a bird, and hit the windage brake device at the maximum speed of the train to test the strength and performance of the windage brake device when it is hit.

[0072] Through specific tests, the present invention further improves the structure of the parts or components of the wind resistance brake device with concentrated stress and large strain, and optimizes the selection of suitable component materials, thereby further ensuring the structural safety of the wind resistance brake device.

[0073] The present invention studies the structure of the windage brake device from three aspects: static strength, fatigue strength and impact strength, by combining simulation experiments with corresponding tests, with high accuracy and reliability. The device structure is optimized based on the results, thereby ensuring that the windage brake device structure meets the emergency braking safety requirements.

[0074] In some embodiments, before step S1, after step S2, or between step S1 and step S2, step S4 is further included: adjusting the control system corresponding to the windage braking device so that the control system meets the preset failure rate requirement.

[0075] Specifically, the preset failure rate requirement may be set to meet the safety level requirement of SIL4.

[0076] Furthermore, the present invention discloses that step S4 specifically includes:

[0077] Step S41: sort out and summarize all faults to obtain various fault modes.

[0078] Specifically, based on the working principle of the emergency brake command system corresponding to the windage brake device, all possible faults are sorted out and summarized to obtain various fault modes, such as driver brake control handle failure, emergency brake button failure, passenger emergency brake failure, etc.

[0079] Step S42: Determine the failure impacts caused by different failure modes and make a list.

[0080] Specifically, the checklist is an FMECA checklist.

[0081] Step S43: Determine the top event of the fault tree based on the checklist and severity level, and analyze the working mechanism of the fault component to determine each sub-fault component to construct the fault tree.

[0082] Step S44: Use the minimum cut set method to perform qualitative analysis on the fault tree to obtain each minimum cut set A i .

[0083] Step S45: Use the cut set probability summation method to quantitatively calculate the fault tree, solve the failure rate of each minimum cut set and sum them to obtain the top event failure rate R 顶 : Where: n is the number of minimum cut sets, R(A i ) is the failure rate of the i-th minimum cut set.

[0084] Step S46: The top event failure rate R 顶 Compare with preset failure rate requirements and optimize control system and fault tree.

[0085] The present invention analyzes the transmission security of windage brake emergency brake instructions based on safety integrity level, FMECA method and fault tree analysis method, and determines the weak points of the system according to the analysis results, so as to perform corresponding optimization to ensure its safety.

[0086] The various embodiments in this specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the various embodiments can be referenced to each other.

[0087] The above description of the disclosed embodiments is intended to enable one skilled in the art to implement or use the present invention. Various modifications to these embodiments will be readily apparent to one skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention is not limited to the embodiments shown herein but is intended to conform to the widest scope consistent with the principles and inventive features disclosed herein.

[0088] Throughout this specification, references to terms such as "one embodiment," "example," or "specific example" indicate that the specific features, structures, materials, or characteristics described in conjunction with that embodiment or example are included in at least one embodiment or example of the present invention. In this specification, schematic representations of these terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

[0089] The preferred embodiments of the present invention disclosed above are intended only to help illustrate the present invention. These preferred embodiments do not exhaustively describe all details, nor do they limit the present invention to specific embodiments. Obviously, many modifications and variations are possible based on the contents of this specification. These embodiments are selected and described in detail in this specification to better explain the principles and practical applications of the present invention, thereby enabling those skilled in the art to better understand and utilize the present invention. The present invention is limited only by the claims and their full scope and equivalents.

Claims

1. A method for ensuring emergency braking safety with air resistance braking, characterized in that, Including: Step S1: Calculate and obtain the wind load borne by the wind resistance braking device through fluid simulation software, and conduct static strength simulation, fatigue strength simulation, and impact strength simulation respectively. Optimize the structure of the wind resistance braking device according to the simulation results. Step S2: Design the opening method and shape of the braking airfoil of the wind resistance braking device, and design the method of arranging the braking airfoil on the train. Conduct simulation analysis on the train equipped with the wind resistance braking device through fluid simulation software. Optimize the opening method, shape, and arrangement method of the braking airfoil on the train according to the simulation results.

2. The method for ensuring emergency braking safety of the air resistance braking according to claim 1, characterized in that, The specific steps of calculating and obtaining the wind load borne by the wind resistance braking device through fluid simulation software in Step S1 include: Determine the three-dimensional model of the device and the calculation domain of the wind resistance braking device, and divide the grid of the three-dimensional model of the device. Select the k-ε two-equation turbulence model, and obtain the pressure contour of the six-degree-of-freedom aerodynamic force after calculation and data post-processing.

3. The method for ensuring emergency braking safety of the wind resistance braking according to claim 2, characterized in that The static strength simulation in the step S1 specifically includes: taking the six-degree-of-freedom aerodynamic force as the braking wing load of the wind resistance braking device to obtain the equivalent stress σ of each component of the wind resistance braking device, 等效 the nephogram, and checking whether each component of the wind resistance braking device meets the material strength requirements, where: σ1 is the maximum principal stress; σ2 is the intermediate principal stress; σ3 is the minimum principal stress; The fatigue strength simulation in Step S1 specifically includes: Import the three-dimensional model of the wind resistance braking device, use the six-degree-of-freedom pressure as the load of the braking airfoil, set the time series as white noise, and obtain the fatigue life contour and fatigue damage contour of the wind resistance braking device to determine the service life and safety of the wind resistance braking device. The fatigue impact strength simulation in Step S1 specifically includes: Import the three-dimensional model of the wind resistance braking device and import the three-dimensional model of the bird body. Set the constraint relationship and material properties of the wind resistance braking device, and set the three-dimensional model of the bird body as water material. Use the train running speed as the initial speed of the bird body to obtain the equivalent stress distribution and strain distribution of the wind resistance braking device under the impact of the bird body, determine the safety of the wind resistance braking device under the impact of foreign objects, and at the same time, find the positions to be strengthened of the wind resistance braking device according to the equivalent stress distribution and strain distribution.

4. The method for ensuring emergency braking safety of the air resistance braking according to claim 1, characterized in that, There is also Step S3 between Step S1 and Step S2: Use a wind load test bench to conduct static strength and fatigue strength test verification on the wind resistance braking device respectively. Conduct impact strength test on the wind resistance braking device on a bird strike test equipment. Optimize the structure at the positions where the stress concentration and strain of the wind resistance braking device exceed the preset values, and at the same time optimize the selection of the corresponding component materials.

5. The method for ensuring emergency braking safety of the wind resistance braking according to claim 1, characterized in that, The specific steps of designing the method of arranging the braking airfoil on the train in Step S2 include: Design the installation angle of the braking airfoil on the train with the aerodynamic drag generated by the braking airfoil greater than the preset drag value and the aerodynamic lift generated being zero. Combined with the car body structure of the train, with the goal of the aerodynamic drag provided by the wind resistance braking of the train being greater than the preset drag value, use the orthogonal test method to obtain the installation position of the wind resistance braking device on the train, the lateral spacing and longitudinal spacing between adjacent braking airfoils, and determine the number of braking airfoils. According to the six-degree-of-freedom braking force generated by the air resistance braking device on the train, for the running stability of the train and the vehicle-track disengagement rate C 脱轨 , the wheel weight change coefficient C 轮重变化 , design the installation method of the air resistance braking device on the train.

6. The wind resistance braking emergency braking safety guarantee method according to claim 5, characterized in that, The vehicle track disengagement rate C 脱轨 : The wheel weight change coefficient C 轮重变化 : Where: F 横 is the lateral force on the wheel of the train; F 垂 is the vertical force on the wheel; F 垂差 is the difference between the maximum and minimum values of the vertical force on the wheel; F 垂均 is the average value of the lateral force on the wheel.

7. The method for ensuring emergency braking safety of the air resistance braking according to claim 1, characterized in that, The specific simulation analysis of the train installed with the wind resistance braking device by using fluid simulation software in step S2 includes: using fluid mechanics calculation software to calculate the aerodynamic loads of the train installed with the wind resistance braking device under crosswind conditions, passing-by conditions and tunnel passing conditions respectively, and evaluating the impact on the running safety of the train.

8. The method for ensuring the emergency braking safety of the wind resistance braking according to claim 1, characterized in that when designing the braking airfoil of the wind resistance braking device in step S2, a locking mechanism needs to be provided on the braking airfoil so that when the braking airfoil can be opened to a preset angle, the braking airfoil is locked.

9. The air resistance braking emergency braking safety guarantee method according to any one of claims 1-8, characterized in that Before step S1, after step S2 or between step S1 and step S2, there is also step S4: adjusting the control system corresponding to the wind resistance braking device so that the control system meets the preset failure rate requirements.

10. The method for ensuring emergency braking safety of the wind resistance braking according to claim 9, characterized in that, The specific content of step S4 includes: Step S41: Sort out and summarize all faults to obtain various fault modes; Step S42: Determine the fault impacts caused by different fault modes and list them; Step S43: Based on the list and the severity level, determine the top event of the fault tree, and analyze the working mechanism of the faulty components to determine each sub-faulty component to construct the fault tree; Step S44: Qualitatively analyze the fault tree using the minimal cut set method to obtain each minimal cut set A i ; Step S45: Use the cut set probability summation method to quantitatively calculate the fault tree, solve the failure rates of each minimal cut set and sum them up to obtain the top event failure rate R 顶 : Where: n is the number of minimal cut sets, and R(A i ) is the failure rate of the i-th minimal cut set; Step S46: Compare the failure rate R of the top event 顶 with the preset failure rate requirement, and optimize the control system and the fault tree.

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