Stochastic vibration analysis of maglev vehicle-guideway coupling system based on PDEM

To study the random vibration of guideway caused by high-speed maglev vehicle, a stochastic vibration model of maglev vehicle-controller-guideway coupled system was proposed. The number theory method(NTM) was employed to select the N-dimension representative point sets and the stochastic harmonic functions(SHF) was utilized to generate the random track irregularity samples, and the general probability density evolution method (PDEM) was adopted to analyze the dynamic responses of the maglev system. The Newmark-β integral method and the double-side finite deference method with TVD(total variation diminishing) scheme were adopted to calculate the probability density function, mean value and standard deviation. Taking the electromagnetic suspension vehicle passing through a continuous guideway as an example, firstly, the random dynamic responses and probability density function of vehicles and guideway were calculated. Meanwhile, the Monte Carlo method (MCM) and the results in literature were used to verify the calculation efficiency and accuracy of the proposed method. Finally, the influence of the vehicle running speed and the bearing support stiffness on random dynamic responses was analyzed and discussed. The results show that the model based on PDEM is more accurate and efficient than MCM with calculation efficiency increasing by 1-2 order of magnitudes. With the excitation of random irregularity, the regularity degree of the contour of probability density function from small to large is mid-span acceleration of guideway, the first car acceleration and the mid-span deflection, respectively. The stochastic dynamic response of vehicle-bridge system tends to increase with the increase of the vehicle speed, but does not increase in linear. The mean value of dynamic responses of vehicle and guideway decreases with the increase of bearing stiffness and tends to be stable gradually, and the vibration will be amplified when the flexible supports are used. © 2022 Central South University of Technology. All rights reserved.