Car Body Self-Vibration Frequency Study

Railage is one of traffic modes in our country. It plays an important role in our national economy. Railcars, carrying passengers and goods, are main tache in the railage. With the development of society, railage makes higher and higher demands on railcars. The past rolling stock structure design belonged to analogy and experience type, only calculating car-body static intensity and stiffness. Recently with the emergence of high-speed train, the problem of car-body vibration is increasingly valued. This needs to calculate, analyze and test car-body's dynamic character on the basis of car-body static intensity. At present, the study of rolling stock system's inherent characer, dynamic design and structure dynam response has gradually taken modal analysis method in the field of railway locomotive & rolling stock. Car-body is an important part of rolling stock. There are many factors that would affect test precision in the spot test, such as limitation of perturbed energy, reponse signal magnitude, perturbed position, perturbed direction, supporting constrain and so on. So it is very necessary to calculate and analyze them. From the dynamic performance of overall rolling stock system, not only analyzing car-body and bogie vibration rules, but also considering the coupled action between them in order to avoid the range of their resonance frequency.As a part of 863 plans "railway vehicle's virtual prototype system", on the basis of having creating car-body, bogie and whole model, the paper respectively calculated their modals, finding out rational hitting position and direction for vertical and transverse bending mode by calculating steel structure car-body's response in the frequency-domain. On the basis of calculating the whole car model, changing one order vertical bending frequency of car-body, analyzing the coupled relationship between car-body verical bending vibration and bogie sink-float frequency in order to avoid resonance vibration range of them and improve traveling amenity and structure fatigue life of rolling stock.