复合固体推进剂等效力学性能VCFEM细观预示方法

根据固体推进剂的细观结构特征，采用等圆最优装载方式生成代表性体积单元（Representative Volume Element，RVE）模型，并结合Voronoi单元有限元方法（Voronoi Cell Finite Element Method，VCFEM）和均匀化方法，发展了一种可预示固体推进剂等效力学性能的数值分析方法，从而得到体分比和组分材料对等效模量和等效泊松比的影响规律。为证明该方法的有效性，设计一个对称数值模型，通过对该方法和传统有限元方法的节点位移结果的比较，发现两者之间的相对误差小于5%，且VCFEM用少量单元就完成了分析，提高了计算效率。通过对不同细观结构下推进剂RVE模型的计算，发现随着夹杂体分比的增大，夹杂的颗粒增强效应越明显，基体材料的变化比夹杂材料对等效力学性能有着更加显著的影响。
The RVE (representative volume element) models were generated by using the equal circle optimal circular packing scheme to characterize the microstructure of solid propellants. In order to obtain the influence laws of volume fraction and component material on effective modulus and Poisson′s ratio, a numerical analysis method for evaluating effective mechanical properties of solid propellants was developed by combining the VCFEM (Voronoi cell finite element method) and the homogenization method. The displacement result of a symmetric numerical example was compared with the traditional finite element method for validating the effectiveness of this method. The relative error between the two methods is less than 5%. The analysis efficiency is improved by using VCFEM, because it needs fewer elements. Moreover, the RVE models of different microstructures were calculated. It is found that with the increase of particle volume fraction, the enhancement effect of particles is more obvious. And the matrix material has a more significant influence than the inclusion material on the effective mechanical properties. 