Configuration design of soda-lime glass laminated transparent armor by finite element analysis

The goal of this research is to design a lighter weight soda-lime glass/polyvinyl butyral (PVB) laminated transparent armor capable of NIJ level III ballistic protection by finite element analysis (FEA) technique. The armor and projectile with impact velocity at 853 m/s was modeled in 3D using quarter symmetry. The meshing parameters and material model were calibrated to obtain the reliable accuracy in FEA results.The effects of the striking glass thickness (19, 15, 12, 10, 8, 6 and 3 mm), PVB film (0.76 and 1.52 mm) thicknesses/ordering and the glass/PVB film configurations with reduced total target thickness on the ballistic performance were systematically examined. The FEA results were analyzed and compared to ballistic testing results in terms of the volumetric damage, the distribution of internal and kinetic energy in the laminates, the depth of penetration, and the crater diameter. These results will be subsequently used to evaluate the ballistic performance of laminated armor designs and to identify the optimal design for lighter weight laminated armor as compared to the reference design.Lastly, the thinnest and lightest-weight soda-lime glass/PVB laminated transparent armor in this study could reach 13.13% and 13.62% of thickness and weight reductions, respectively, comparing to the commercial models. Thus, it could indicate that the FEA performed using ANSYS explicitSTR® software is a powerful tool for the study of the ballistic impact process, the damage propagation, as well as in optimizing the design of laminated transparent armor systems.本研究旨在通过有限元分析（Finite Element Analysis, FEA）技术，设计一款满足美国国家司法协会（National Institute of Justice, NIJ）三级弹道防护标准的轻量化钠钙玻璃（soda-lime glass）/聚乙烯醇缩丁醛（polyvinyl butyral, PVB）层压透明装甲。 本研究以弹体初速853 m/s的装甲与弹体为研究对象，采用四分之一对称建模方法构建三维仿真模型。为保障有限元分析结果的可靠精度，对网格划分参数与材料模型进行了校准。 系统考察了受击玻璃厚度（19、15、12、10、8、6及3 mm）、PVB薄膜厚度（0.76 mm与1.52 mm）及铺层顺序，以及缩减总靶板厚度的玻璃/PVB薄膜配置方案对弹道防护性能的影响。 对有限元分析结果进行分析，并从体积损伤、层压板内部能量与动能分布、侵彻深度及弹坑直径等维度，与弹道试验结果开展对比。后续将基于上述结果评估层压装甲设计的弹道防护性能，并相较于参考设计，遴选出轻量化最优的层压装甲设计方案。 本研究所得最薄且质量最轻的钠钙玻璃/PVB层压透明装甲，相较于商用型号，厚度与质量分别可降低13.13%与13.62%。由此表明，采用ANSYS ExplicitSTR®软件开展的有限元分析，是研究弹道冲击过程、损伤传播以及优化层压透明装甲系统设计的高效可靠工具。