Nonlinear Frequency Response Analysis and Jump Avoidance Design of Molecular Spring Isolator

Molecular spring vibration isolation technology has been invented in the recent years but it still needs further development in dynamics theory. A molecular spring isolation (MSI) consists of water and hydrophobic zeolites as working medium, providing high-static-low-dynamic stiffness. The dynamic properties of MSI are thoroughly investigated in this paper. Firstly, the nonlinear dynamic model of a vibration system support by MSI, i.e. the equation of motion, is established. Then the averaging method is employed to estimate the frequency response function (FRF) of the primary resonance. The phase trajectories diagram evolvement of primary resonance is also investigated to analysis the stability of the primary resonance response. From the plot of FRF, it is found that there exists a jump phenomenon induced by nonlinear stiffness, which may have harmful impacts on the equipment which is supposed to be protected from vibrations and shocks. To avoid jump, the FRF is analyzed to find the critical values of system parameters and a jump avoidance criterion is introduced.