Design And Parameters Optimization Of Vibration Mitigation Structure With Inerter

As a new mechanical component,inerter provides new design ideas for vibration control of mechanical systems,making the classic passive vibration reduction and isolation structure extend from "Spring-Damping" to "Inerter-Spring-Damping".This thesis introduces the ISD structure into the dynamic vibration absorber.The design and parameter optimization of DVA with inerter is studied,and the vibration mitigation based on ISD structure is also investigated.The main research contents are as follows:(1)The single degree of freedom vibration system and the DVA’s specific optimization method as well as the mechanical performance of inerter are discussed,which building the theoretical foundation for subsequent calculation and optimization.(2)The inerter is connected with the Kelvin and Maxwell models in series and in parallel respectively.The influence of the inerter on the system responses is studied under three different forced excitations.Through the comparison of the amplitude amplification factors and amplitude-frequency response curves,it is found that the parallel connected inerter can reduce the natural frequency without changing the stiffness or the mass.The parallel connected inerter will make the resonance zone ahead and has a good effect on vibration reduction and isolation.The series connected inerter has a good effect on vibration reduction and isolation under forced vibration caused by simple harmonic excitation and support movement.(3)The ISD structure is introduced into the dynamic vibration absorber.A numerical searching optimization process is built by computer programming.The analytical result of the classic grounded DVA is used to compare with the numerical one,which verifies the correctness and rationality of the numerical process.Then,based on the numerical process,the parameters of these six types of DVAs with inerter are optimized and their optimal numerical solutions are obtained.Comparing with traditional DVA,it is found that introducing ISD structure into dynamic vibration absorber in a suitable combination form has a good effect on vibration reduction.(4)The ISD structure is introduced into the single degree of freedom vibration reduction system,the optimal parameters of the system are obtained by fixed point theory and H Infinity optimization.The responses of the models are compared with the traditional dynamic vibration absorber under harmonic excitation and random excitation.The results show that the ISD structures have good effects on vibration mitigation compared with the traditional DVA.Finally,we summarized and prospected this paper,given the next research content and direction.