Investigation On Prediction And Control Of Railway Wheel-Rail Rolling Noise

With the development of the high-speed railway and the urban rail transit, the social requirement to decrease railway noise is growing rapidly. The predominant railway noise is wheel-rail rolling noise, and the prediction and control of rolling noise is necessary to be further studied.Based on Remington's prediction model and the finite element analysis model of the wheel and rail, a model for predicting wheel-rail rolling noise is given in this dissertation. In the model, besides the vertical rolling noise of the rail and the wheel, the axial wheel rolling noise is taken into account, and the finite element method is used to investigate the dynamic behaviors of the wheel and the rail. Compared with the results measured, the differences between measured and predicted overall A-weighted sound press levels is less than 2~3dBA nearby the rail and 1dBA at the railway boundary. With the model, the influence of key parameters of noise prediction on rolling noise is studied.A method of predicting the rolling noise of resilient wheel is given, based on the rolling noise prediction model of all-steel wheel and the correction for modal damping loss factor and the wheel radial response in which the finite element method is used. It is found that the change of rolling noise spectra and the effect of the stiffness of the resilient layer and the material loss factor on wheel-rail rolling noise are consistent with the published analysis and data. The configuration of constrained layer damping treatments is considered, and the wheel-rail rolling noise of damped wheel is predicted. Significant reduction in the wheel rolling noise is showed to be possible.With the objective reducing rolling noise emission, cross-sections of the wheel and rail are optimized. It is found that the wheel or rail optimized can reduce its own sound level effectively and affects the other little, and wheel and rail are optimized respectively is feasible. In the optimization of the wheel, the hub thickness and the shape of the web, rim and fillets are studied respectively. Result show that reduction in wheel rolling noise is significant, however, reduction in overall noise is less than 1. 31dBA because of the poor reduction in rail noise and its high configuration to overall noise. As for the rail, the peak value of rail rolling noise is chosen as objective function. Result shows that the reducing effect is 1.48dBA for overall noise with initial wheel, and reduction in overall noise is up to 4.15dBA with the optimal wheel. So, It is indicates that initial spectra of wheel-rail rolling noise are important to optimization.Noise barrier is one of main measures for reducing the rolling noise and is still costly, and a major reason is that the design parameters are improper. So, cost of noise barrier is chosen as objective function, the requirement of noise reduction as acoustic constraints in the optimization model. The angle of inclination, the vertical distance, the height and length of noise barrier are taken into account in design variables. Results of studies on various shapes show that any design parameter is important to noise reduction and cost of noise barrier, and the new design method can lead to important saving in the costs of noise barrier. Compared with vertical barrier, trackside low barrier and bevel barrier has higher cost-effectiveness at an appropriate distance close to noise resource and better performance of noise reduction.