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将有限元模型的质量和刚度矩阵减缩为试验-分析模型(其自由度对应于模态测试加速度计的位置)的方法有几种,这里比较了其中4种——静态减缩法(Guyan法)、改进的减缩系统(IRS)法、模态减缩法和复合式减缩法的精确性和完善性。用两个算例进行了比较:一个一般航天器的简单有限元模型与模拟试验数据的比较和一个大型航天结构的预示有限元模型与相应的模态测试结果的比较。算例研究表明,减缩过程的质量是一不取决于具体减缩法的问题,任一减缩法并不明显优于其他方法,但改进的减缩系统法对静态法作了改进,复合式减缩法对模态减缩法作了改进。本文在每种减缩法之后还介绍了理论性内容。
There are several ways to reduce the mass and stiffness matrix of the finite element model to a test-analysis model (the degree of freedom corresponds to the position of the modal test accelerometer), where four of them are compared - the Guyan method, , Improved reduction system (IRS) method, modal reduction method and composite reduction method accuracy and perfection. Two examples are compared: a comparison of a simple finite element model of general spacecraft and simulated test data, and the comparison between the predicted finite element model of a large aerospace structure and the corresponding modal test results. The case study shows that the quality of the reduction process is a problem that does not depend on the specific reduction method. Either reduction method is not superior to other methods, but the modified reduction method improves the static method. The compound reduction method Modal reduction method has been improved. This article also introduces the theoretical content after each reduction method.