【摘要】 模态展开法是计算振型一阶导数的常用方法,然而,当高阶模态被截断时,它不能给出精确解,甚至会产生很大的截断误差。本文研究被截断的高阶模态对振型导数贡献的定量计算问题,证明了被截断模态的贡献可以用已知的低阶模态和系统矩阵来显式表达,给出了计算方法,并用数值例子说明了本文方法的有效性和正确性。更多还原

【Abstract】 The modal superposition method is often used to obtain mode shape derivatives. However, it can not give an accurate solution and the errors may become significant, when more high-frequency modes are truncated. This paper deals with the contribution due to the unavailable high-frequency modes to mode shape derivatives, proves that it can be expressed by the available low-frequency modes and the system matrixes, and presents a numerical algorithm. Numerical examples show that the method is correct and can improve greatly the accuracy.更多还原