Research And Optimization Of Dynamic Comfort Of Railway Passenger Train Based On Nonlinear Energy Sink Technology

With the continuous development and innovation of railway technology,high.speed train has developed rapidly in railway traffic.At the same time,passengers’ requirements for high.speed train ride comfort are getting more and more different,and people pay more and more attention to the ride comfort of the train.There is direct contact between train seats and passengers,which plays the role of supporting the human body and cushioning the vertical vibration of the train.Therefore,it is necessary to improve the dynamic comfort of the train to enhance the ride experience.The main work of this paper is to establish the dynamic model of the interaction between passenger and seat by using lumped parameter modeling method,and to simulate and analyze the vibration coupling of the train seat in the vertical direction.Secondly,due to the influence of many factors,such as the irregularity of the track,the excitation vibration signal of the seat will produce transient impact component,which is decomposed into two parts: stationary random vibration and transient impact.Then,the response of the seat vibration system with energy sink device is analyzed,so that the energy generated by random vibration of the seat can be absorbed by the energy sink as far as possible,so as to improve the ride comfort.Finally,the parameters of the nonlinear energy sink device are optimized with the grid search optimization algorithm,so as to minimize the energy value transmitted to passengers.Data simulation and decomposition of seat system.The wave spectrum is used to simulate the excitation and response vibration waveform of the train seat system under real conditions,which represents the running state of the train at different times.When the train is swinging vertically,the vibration signal received by the seat contains random mutation,which results in the non.stationary and non.Gaussian phenomenon of the signal.Therefore,the mutation signal should be separated from the whole wave signal.Based on the theory of wavelet transform,the abrupt components of the vibration signal of the seat are separated,and the abrupt location of the signal can be located by finding the intersection.Response analysis of seat vibration system with nonlinear energy sink.For seat comfort improvement in a train,the nonlinear energy sink(NES)device has the advantages of simple structure and vibration absorbing the advantages of high efficiency,and the connection of NES device seat vibration system is studied,combined with the numerical simulation analysis of the stability of the seat and the dynamic behavior of the whole system,analyzed and compared before and after installing energy sink unit seat response,and its simulation by monte-carlo method for validation,so as to objectively evaluate the energy absorption characteristics of NES.Parameter optimization of seat system with nonlinear energy sink.In order to further improve the comfort,without changing the seat itself under the premise of parameter design,in order to pass to passengers to minimize the energy value,choose the larger influence on NES device as optimization object,the stiffness and damping parameters of using grid search optimization algorithm,optimization model is established,the optimization results of related parameters,the optimization results show that the ride comfort of the train get better improve performance and prove the grid search algorithm is used to solve the problem of train seat parameters optimization is feasible.