Mechanical Properties Of Viscoelastic Materials Modeled By Fractional Derivative And Application Study On Suppressing Vibration Of Structure

Due to the requirement of vibration reduction of structures and the development of material industry, damping materials have being developing, especially, the polymer damping materials are paid more and more attention because of their features of both viscous liquid and elastic solid properties. Good energy dissipation and damping properties.If the new material whether would enter onto engineering application from theoretical study and laboratory, the fundamental work is supposed to be modeling accurately in order to obtain its mechanical properties and required performance indices. Vicoelastic damping materials depend greatly on the environmental factors such as temperature,frequency,strain amplitude and so on, which present difficulties for constitutive modeling and the study of their mechanics properties.Comparing with classical viscoelastic models, fractional derivative models describe not only the constitutive of viscoelastic material and the related mechanics properties accurately in wide range, but also need less model parameters. This thesis presents the theoretical studies on viscoelastic materials modeled by fractional Kelvin and fractional Maxwell models, the result show that the properties of viscoelastic materials with fractional operator depend on not only the change of angular frequency, but also the fractional operator r; With one and two degrees of freedom are carefully studied in the thesis, which lie down the foundation for the application in vibration isolation and reduction charactoresties of fractional oscillator.As a typical high-speed rotor system, the dynamic performances of high-speed CD-ROM with polymer damper were investigated in detials. Now,viscoelastic damping suppressing vibration technique used by high performance viscoelastic materials have been applicated frame structure of CD-ROM;The Marc FEM software analysis is used to viscoelastic suppressing vibration frame structure of CD-ROM and some institutive results have been achieved, which would be basis for further careful studies.