屈曲薄膜振动分析

VIBRATIONS ANALYSIS OF BUCKLING MEMBRANE

非线性大变形屈曲分析是处理薄膜褶皱问题的一种有效方法,该文对这种方法的两个关键问题进行了探讨,包括初始缺陷的施加及后屈曲平衡路径的跟踪。基于这种方法分析了剪切薄膜的褶皱,并在褶皱构形的基础上,进行了考虑大变形效应的模态分析。分析结果表明:具有褶皱薄膜振动的模态及固有频率与不具有褶皱的薄膜相比明显的不同,褶皱薄膜的固有频率明显的减小了,其节线的位置为张拉线的位置,随着模态的增加其节线的数目减少。该文所建立的分析过程,不但能够进行薄膜褶皱的分析,同时也能分析褶皱形成后薄膜的动态特性。

Nonlinear large deformation buckling analysis is an effective method dealing with membrane wrinkle problems. Two key issues of this method, the introduction of original flaw and the follow of post-buckling balance path, are discussed in this paper. According to this method, wrinkles of shear membrane are analyzed. Based on wrinkle configuration, modal analysis is performed with the consideration of the large deformation. The result indicates that the modal and natural frequency of the membrane with wrinkles are obvious different from the membrane without wrinkles. The natural frequency is decrease sharply; the position of pitch lines are that of tensile lines, and the number of pitch lines is decrease as mode increased. The analytical process established in the paper can be used for membrane wrinkles prediction and dynamic characteristics analysis with wrinkles.