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收敛的有限元模型通常是意识到通过观察网格独立性。在线性系统不变的线性模式进一步网格细化常被用来评估网格独立性。然而,这些线性模型往往伴随着非线性元素如CFD模型,非线性控制系统,或关节动力学。一个非线性元素的引入可以显著改变网格细化的程度所必需的足够的模型精度。应用非线性模态分析[1,2]说明使用线性模态融合作为衡量网格质量的非线性是不够的。收敛的非线性简正模简支梁模型检查使用有限元素。Boivin的解决方案进行了比较,皮埃尔,肖[3]。这两种方法都受到需要在幂级数近似收敛。然而,有限元建模方法引入了网格独立性的额外的关注,即使啮合模型的线性部分,除非使用p型元素[4]。的重要性,搬到一个非线性模态分析有限元方法是解决问题的能力的一个更复杂的几何不存在封闭形式的解决方案。 This case study demonstrates that a finite element model solution converges nearly as well as a continuous solution, and presents rough guidelines for the number of expansion terms and elements needed for various levels of solution accuracy. It also demonstrates that modal convergence occurs significantly more slowly in the nonlinear model than in the corresponding linear model. This illustrates that convergence of linear modes may be an inadequate measure of mesh independence when even a small part of a model is nonlinear.