基于真实细观形貌的固体推进剂力学性能虚单元预示方法OA北大核心CSTPCD

The real mesomorphology is the basis for predicting the mesomechanical properties of solid propellants.The real me-so-geometry morphology and component parameters of the solid propellant were obtained by processing the CT scan images,and the solid propellant particle filling model was generated.The polygonal mesh division scheme was adopted to reduce the effect of low-quality mesh caused by the difference of particle size of each component when using conventional elements.Through the post-pro-cessing of the elements and nodes,the periodic boundary condition processing scheme was designed to deal with the real mircomor-phology.The virtual element method(VEM)was introduced to predict the mesomechanical properties of solid propellants.The fea-sibility and accuracy of VEM and periodic boundary condition treatment schemes were verified by designing examples with inclu-sions.The effect of"dewetting"between matrix and particles was simulated by cohesive element,and the equivalent relaxation modulus was tested for the real mesoscopic model and the particle-filled model.The simulation results show that the irregular parti-cle geometry in the real mesoscopic model can inhibit the phenomenon of"dewetting",and the equivalent relaxation modulus of the model is larger than that of the particle-filled model.In addition,the maximum relative error of the relaxation modulus predicted by the two types of models is 13.1%,which indicates that the particle filling model can replace the real geometric model to predict the equivalent mechanical properties of solid propellants in the design of propellant formulation.Combined with the advantages of VEM in dealing with the geometric scale difference of solid propellant components and the design of periodic boundary conditions,VEM can be further used to predict the mechanical properties of three-dimensional solid propellants.