Authors: Jae Hyuk Lim JeanBaptiste Charpentier Dongwoo Sohn
Publish Date: 2015/03/15
Volume: 29, Issue: 3, Pages: 1187-1197
Abstract
In this work the coefficients of thermal expansion CTEs of fibers in composite materials that contain microstructures are numerically evaluated using a laminascale cost function with quasianalytical gradients To consider the effects of fiber arrangements and local defects such as interface debonding and voids a variety of representative volume elements are modeled with a number of finite element meshes Then the CTEs of fibers are evaluated by minimizing a laminascale cost function that represents the difference between the measured CTEs and the computed CTEs by means of a computational homogenization scheme for the composite lamina The descent direction of the cost function is obtained using quasianalytical gradients that take partial derivatives from prediction models such as the Schapery model and Hashin model defined in an explicit manner which accelerates the minimization procedure To verify the performance of the proposed scheme in terms of accuracy and efficiency the CTEs of constituents calculated using the proposed scheme in a unidirectional composite lamina are compared with experimental values reported in the literature Furthermore the convergence behavior of the proposed scheme with quasianalytical gradients is also investigated and compared with other minimization methodsJae Hyuk Lim received his BS degree in Mechanical Engineering from Inha University Korea in 2000 He received his MS and PhD degrees in Mechanical Engineering from the Korea Advanced Institute of Science and Technology KAIST in 2002 and 2006 respectively He is currently a senior research engineer in the Satellite Mechanical Department Korea Aerospace Research Institute His research interests include finite element simulations material modeling and characterization and design and analysis of satellite structuresDongwoo Sohn received his BS degree from Hanyang University Korea in 2006 He received his MS and PhD degrees from the Korea Advanced Institute of Science and Technology KAIST in 2008 and 2011 respectively He is currently an assistant professor in the Division of Mechanical Engineering Korea Maritime and Ocean University His research interests include numerical methods and computational mechanics
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