Study On The Dynamic Characteristics Of Truck Body And Key Suspension Parts Of Special Railway For Automobile Transportation

Nowadays the world’s railway freight is developing towards high speed and heavy load,which also puts forward higher requirements for China’s railway freight capacity.Railway freight car is the core equipment of railway freight transport,and SQ₆sunken bottom double-deck transport special car is the main type of freight car of railway transport car,which plays an irreplaceable role in railway transport.And accompanied by a new type of vehicle load and the constant improvement of the parameters such as speed,vehicle vibration fatigue damage of the key components is becoming more and more,the vibration of the component fatigue failure problems on high speed vehicle driving safety,so the vehicle components reliability has become an important goal of the new car design should be considered.This paper takes the air cylinder of SQ₆type sunken bottom double-deck transport special vehicle as the research object,aiming at the fatigue failure problem of the component,adopts the research method of combining finite element analysis and test to conduct in-depth research on the failure reason and optimization scheme of the air cylinder structure.The main contents of this paper include:（1）To understand the development history,technical status,structural characteristics and application conditions of domestic and foreign transport vehicles.Investigate and analyze the fatigue failure problem of key components in vehicle operation,determine the special simulation and test analysis method for this problem,and work out the corresponding technical scheme.（2）Based on the finite element analysis theory,the finite element analysis software is used to establish the finite element model of the car body and the wind cylinder structure,and conduct modal analysis,so as to master the modal shape and related frequencies of the car body and the wind cylinder structure.（3）Conduct harmonic response analysis based on the modal analysis results of Ansys software,and combine with the random vibration analysis module of Ncode software to analyze the wind cylinder structure.The analysis results provide a reliable basis for the final determination of the test scheme.（4）According to the results of finite element analysis and the preliminary investigation and study,determine the vehicle’s test conditions,the location of the measuring points and the detailed plan of data acquisition.（5）The vibration response analysis of the vehicle is carried out through the bench test,and the vibration state of the vehicle in the operating environment is reproduced by taking the five-stage spectrum of the United States and the trunk spectrum of China as the excitation signals,and the vibration response signals of key parts are collected to evaluate the dynamic stress level of each measuring point.（6）Based on the working mode analysis theory,the Test.Lab software was used to establish the working mode analysis model.Combined with the measured data,the modal characteristic parameters of the vehicle body and the air cylinder structure were obtained,and the main frequency components of each structure were analyzed.Based on the above analysis results,the fatigue failure reason of the air cylinder structure is determined.（7）Analyze the results of simulation and test,propose the corresponding structural optimization scheme,and conduct simulation and test verification of the optimized structure,and finally determine the optimal design scheme.