一种分析具有局部非线性的多自由度动力系统动力特性的方法

对于具有局部非线性的多自由度动力系统，提出一种有效方法，该方法将线性自由度转换到模态空间中，并对其进行缩减，而将非一自由度仍保留在物理空间中，避免了在数值分析中求非线性因素时的坐标转换。

A method for analyzing the dynamics of mechanical systems with local nonlinearities

The number of degrees of freedom (DOF) of the linear components of a system with local nonlinearities is reduced by the component mode synthesis technique based on fixed interface eigenmodes and bound flexibility modes. The order of linear DOF of the system is reducted only, while the nonlinear DOF is still in physical space. A Newmark's Scheme Based Predictor Corrector Algorithm is presented for analyzing the long tem dynamics of reduced dynamic system, and this algorithm is iterative with nonlinear DOF only. The convergence of this algorithm is rapider than that of the classical Newmark integration schemes. A numerical example is presented, it is found that the method is effective for analyzing the long term behavior of mechanical systems with local nonlinearity.