Dynamic Modeling Research Of Transmission Shaft Based On Multi Rigid-flexible Body Theory

In a driving vehicle,the shaft system normally has inevitable noise and vibration because of its structural feature and the high speed revolution.This noise can have a negative effect on machine's normal operation,even to the point of causing structural damages.Therefore,vibration analysis and control on shaft system has been a growing concern.On the full reference of relevant literatures home and abroad,this article makes a deep research on dynamic performance of shaft system by combining the transfer matrix method with test analysis.With this algorithm,a certain type CVJ is simulated to make sure its natural frequency and vibration mode,also to solve quantitative equation between the absorber parameters and the performance vibration.After the CVJ has been tested with B&K vibration system,the testing result shows a reasonable agreement with previous theoretical model analysis.It suggests that the simulation algorithm is valid for CVJs' kinetic study as well as its vibration and noise reduction,and is valuable in more practical application.In the first part,according to the transverse bending vibration of transmission shaft,kinetic model has been built based on the theories of rigid-flexible multibody system and generalized Hamiltonian Principle.Then the partial differential equation has been transferred to ordinary differential equation through the Galerkin method,so as to find a simulation algorithm to the vibration performance of rigid-flexible multi-body system for the shaft system.In the second part,with this algorithm,a certain type transmission shaft is simulated to make sure its natural frequency and vibration mode,also to solve quantitative equation between the absorber parameters and the performance vibration.This method calls for no overall kinetic equation building for multibody system.Instead,optical homologue,optical damping ratio and many other optical conditions are used as theoretical foundation to solve the minimum added mass and the optical installation site for dynamic vibration absorbers.In this way,it not only solves the rigid-flexible parts model coupling,but also accomplishes the parameters optimize design for dynamic vibration absorbers in transmission shafting system.In the last part,after the transmission shaft has been tested with B&K vibration system,the testing result shows a reasonable agreement with previous theoretical model analysis.It suggests a precise model and a valid simulation algorithm can make dynamic performance predictable in transmission shafting system.And it also suggests it is instructive in structural design,vibration and noise reduction,and many more valuable practical application.