Dynamics Analysis And Dimensionality Reduction Of Friction System

Braking action of a brake disc is a local contacting problem,which bringsinfluence to the modes and inherent frequencies of the system. The method of localdiscontinuous basis function can be used to estimate the modes of system accurately.Part One: a brake disc contacted by a friction block, is simplified as aone-dimensional beam model. The equation of motion is established. Firstly, themodes of the free vibration beam were calculated. Then the contact of the frictionblock is simplified as several linear springs. Considering the continuous conditions,the discontinuous modes are calculated and orthogonalized with the referencemodes.,as the supplement of reference mode,used to calculate the system response.Part Two: Compared with the finite difference method, Local discontinuousbasis function method is more accurate.Analyses show that the local contact canrestrain the symmetry of vibration of the brake plate, which leads to the disappearanceof sine or cosine modes. Based on the discontinuous mode analysis, vibration of thebrake disk under action of external excitation is calculated. And the function of thenonlinear stiffness and friction, can make the vibration to be wave type.Part Three: Due to the friction of the brake block, the brake disc is impacted andproduce energy, gathered in the friction piece of contact with the brake disc,so thebrake disc produce larger vibration displacement, in this part, the friction piece canbe converted to moving load acting on the brake disc. the dynamic characteristics ofbrake discs is studied.Part Four: The purpose of research for braking system vibration is to solve the theproblems in the process of braking, so experiment is vital importance.in this part theLocal discontinuous basis function method and Finite difference method is tested andevaluated through the experiment.