区分的に線形な二自由度非線形振動子の強制振動解析

抄録

In this paper, the forced response analysis of two degrees of freedom (DOF) piecewise-linear nonlinear oscillators that are subjected to harmonic excitation and contact between the oscillators. our study shows investigation of the forced response of a two DOF PWL nonlinear system is with experiments and numerical analyses. First, experiments have been setup that are capable of simulating and measuring the dynamics of PWL nonlinear systems. With this experimental setup, forced response tests have been conducted with swept-sine base excitation. To ensure that the components collide with each other during the oscillation, masses of the components have been adjusted such that their natural frequencies differ from each other. As a result, clear features of nonlinearity are observed. In particular, the skewness of the signal envelops of the measured time histories of the displacements have been observed. Second, numerical analyses have been conducted by solving the nonlinear equations of motion of the two DOF PWL nonlinear systems, which contains nonlinear contact forces generated at the contact surfaces. Some discrepancies between experimental and numerical results are found in the frequency range where intermittent contacts between the oscillators occur, i.e., the response is nonlinear. Overall, however, it is observed that the numerical results agree well with the measured results for the frequency range of interest