Vibration Characteristics And Parametric Vibration Research Of Diaphragm Coupling

Diaphragm coupling is able to transmit power between different mechanisms,which has wide application in fields such as heavy machinery,engineering machinery,automobile,haulage motor,shipping,and so on.Diaphragm as a critical component in diaphragm coupling,and analysis and calculation of diaphragm are crucial for the coupling to work.This paper will center on vibration characteristics and parametric vibration under variable rotating speed and torque of diaphragm.In chapter one,research background and significance of this investigation are presented.Following that,research situation of diaphragm at home and abroad is summarized.Besides,a brief introduction of the main content in this paper is given.The flap-wise vibration characteristics of diaphragm are researched in chapter two.The expressions of axial force and moment are obtained by constitutive relation and geometrical relation.Then vibration equation is established,based on Euler-Bernoulli beam theory and d'Alembert principle.Galerkin method is used to disperse the vibration equation and construct the eigenvalue equation for frequencies.In the end,numerical simulations are presented to research the effects of rotating speed and torque on the vibration characteristics of diaphragm.In chapter three,Euler-Bernoulli beam theory,geometric nonlinearity and d'Alembert principle are employed to construct the lead-lag vibration equation.Following that,the assumed-modes method is applied to solve the vibration equation and obtain the characteristics equation for frequencies.And then,FEM simulation is utilized to illustrate the correctness of this method.At the end of this chapter,numerical calculations are presented to research the effects of rotating speed and torque on the vibration characteristics of diaphragm.The nonlinear parametric vibration of diaphragm is studied in Chapter four.The rotating speed is fluctuating around the mean speed.Based on the non-linear equation constructed in chapter two,the partial differential equation is tra nsformed to ordinary differential equation by the Galerkin method,and then the multi-scale method is used to obtain the amplitude-frequency response and steady-state response of diaphragm.At the end of this chapter,numerical calculations are presented to research the effects of mean rotating speed,amplitude of speed variation,and torque on the unstable regions and response curves.The nonlinear dynamical behavior and steady-state response are researched in chapter five.The transmitted torque is varied harmonically about the mean torque.steady-state response of nonlinear flap-wise vibration is obtained by the Galerkin method and multi-scale method.The process is similar to the chapter four.The stability and bifurcation are researched and the effects of rotating speed,amplitude of torque variation,and mean torque on the unstable regions and response curves are also studied.