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Study on the Efficient Dynamic System Condensation  

Baek, Seung-Min (서울대학교 기계항공공학부 대학원)
Kim, Ki-Ook (인하대학교 기계공학부)
Cho, Maeng-Hyo (서울대학교 기계항공공학부)
Publication Information
Journal of the Computational Structural Engineering Institute of Korea / v.20, no.3, 2007 , pp. 347-352 More about this Journal
Abstract
Eigenvalue reduction schemes approximate the lower eigenmodes that represent the global behavior of the structures. In the previous study, we proposed a two-level condensation scheme (TLCS) for the construction of a reduced system. In the first step, the selection of candidate elements by energy estimation, Rayleigh quotient, through Ritz vector calculation. In the second step, the primary degrees of freedom are selected by the sequential elimination method from the degrees of freedom connected to the candidate elements in the first step. In the present study, we propose TLCS combined with iterative improved reduced system (IIRS) to increase accuracy of the higher modes in the intermediate range. Also, it is possible to control the accuracy of the eigenvalues and eigenmodes of the reduced system. Finally, numerical examples demonstrate the performance of the proposed method.
Keywords
system condensation; two-level condensation scheme (TLCS); iterative improved reduced system;
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