Research On The Safety And Stability Of High-speed Train Operation Under Strong Wind Conditions Based On Fuzzy Matter-element

With the rapid development of railway technology worldwide,the number of high-speed trains in China has been increasing,and their operating speed has been getting faster.The interaction between high-speed trains and wind has become more significant,and the aerodynamics and running safety and stability of high-speed trains have received more attention.With a vast territory and complex railway operating environment,strong winds are one of the main factors seriously threatening the safe operation of trains.The effects of strong winds can worsen the aerodynamic performance of trains.Therefore,studying the safe and stable operation of high-speed trains under strong wind is of great significance to ensure the normal operation of railway transportation.This dissertation quantitatively analyzes the interaction between high-speed trains and wind fields from the perspective of mean wind and fluctuating wind.The Karman theory and Davenport coherence function are introduced,and a fluctuating wind load model is established through harmonic synthesis and fast Fourier transform analysis.Using the formula for non-steady aerodynamic loads on high-speed trains under strong wind,it is calculated that the lateral drag load is greater than the vertical lift load under the same wind speed but different train speeds.When the speed increases from 120 km/h to 200 km/h,the fluctuation of the drag load becomes significant,while the change in lift load is not significant.This indicates that the harm of lateral strong winds to high-speed trains is particularly evident.To study the operation of high-speed trains under strong winds,the SIMPACK multibody dynamics software is used to establish a dynamic model of the high-speed train vehicle system,including a single trailer model with 42 degrees of freedom.The safety and stability indicators of high-speed trains under different speeds and different strong wind conditions are calculated by applying loading stimuli to the model.Considering that there are many dynamic evaluation indicators for high-speed trains,selecting information with practical use from numerous data is particularly important.Based on the "Technical Specification for the Evaluation and Test Identification of Locomotive and Rolling Stock Dynamic Performance"(GB/T 5599-2019)in China,derailment coefficient,wheel load reduction rate,lateral force on the wheelset,and Sperling stability index are chosen as decision support objectives.The simulation results show that as the wind speed increases,the safety and stability indicators also increase,which is in line with the actual operation of trains.Considering that the safety and stability indicators of high-speed train operation are affected by various complex factors,a fuzzy matter-element model is constructed.The fuzzy matter-element membership degree,fuzzy matter-element correlation degree,evaluation system construction,and indicator entropy weight establishment are used,and an example verification is conducted to obtain a more systematic and comprehensive evaluation approach.It is proved that the model has outstanding advantages in studying the safe and stable operation of high-speed trains under strong wind.