提出了短纤维复合材料的本征应变边界积分方程计算模型,并采用新发展的边界点法进行了求解.模型依据Eshelby等效夹杂物的概念并借助Eshelby张量,采用迭代方法来计算基体中各种性能短纤维的本征应变,其中所需的Eshelby张量不难通过解析或数值方法获得.由于未知量只出现在边界上,与已有的有限元和边界元模型相比,提出的计算模型可极大地减小异质体问题的求解规模,提高计算效率.通过数值算例计算了代表性体积单元上各种短纤维复合材料的整体弹性性能,验证了计算模型和求解方法的正确性和有效性.
A computational model was proposed for short-fiber reinforced materials with the eigenstrain formulation of the boundary integral equations (BIE) and solved with the newly developed boundary point method (BPM). The model comes intimately from the concept of the equivalent inclusion of Eshelby with eigenstrains to be determined in an iterative way for each short-fiber embedded in the matrix with various properties via the Eshelby tensors, which can be readily obtained beforehand through either analytical or numerical means. As the unknowns appear only on the boundary of the solution domain, the solution scale of the inhomogeneity problem with the model is greatly reduced. This feature is considered to be significant because such a traditionally time-consuming problem with inhomogeneity can be solved most cost-effectively compared with the existing numerical models of the FEM or the BEM. The numerical examples are presented to compute the overall elastic properties for various short-fiber reinforced composites over a representative volume element (RVE), showing the validity and the effectiveness of the proposed computational model and the solution procedure.