CAJ | 학술논문

采用数值仿真方法对单层内空、单层充液和双层充液不锈钢半球形薄壳在冲击荷载下的动力学响应进行了研究并实验结果进行了比较，验证了数值模拟的有效性。利用验证的模型对落锤冲击三种壳结构的变形模态及其变形特点和能量吸收进行的比对研究。分析发现：内空半球壳在冲击作用下产生镜面反射式的下凹变形，冲击结束后没有明显回弹，壳体横截面没有发生扩展；而对于内充液体的壳体，由于内部液体的作用其反射下凹边缘有了较大的过渡区，在“棱区”边缘伴有向外扩展，如果冲击能量足够，冲头会对镜面反射下凹边缘区产生熨平作用，冲击结束后有明显的回弹。单层内空壳体具有较好的吸能能力，但会使壳体产生较大的顶点位移，极大的压缩了壳内的有效防护空间。双层充液半球壳可以在产生不大的变形情况下吸收较大的冲击能量，并在内壳形成一定的防护空间，而单层充液壳体其吸能及变形情况与双层壳的外壳基本一致。
채용수치방진방법대단층내공、단층충액화쌍층충액불수강반구형박각재충격하재하적동역학향응진행료연구병실험결과진행료비교，험증료수치모의적유효성。이용험증적모형대락추충격삼충각결구적변형모태급기변형특점화능량흡수진행적비대연구。분석발현：내공반구각재충격작용하산생경면반사식적하요변형，충격결속후몰유명현회탄，각체횡절면몰유발생확전；이대우내충액체적각체，유우내부액체적작용기반사하요변연유료교대적과도구，재“릉구”변연반유향외확전，여과충격능량족구，충두회대경면반사하요변연구산생의평작용，충격결속후유명현적회탄。단층내공각체구유교호적흡능능력，단회사각체산생교대적정점위이，겁대적압축료각내적유효방호공간。쌍층충액반구각가이재산생불대적변형정황하흡수교대적충격능량，병재내각형성일정적방호공간，이단층충액각체기흡능급변형정황여쌍층각적외각기본일치。
Here,numerical simulations were performed to study dynamic responses of a single-layer empty thin-wall hemispherical shell,a single-layer liquid-filled thin-wall hemispherical shell and a double -layer liquid-filled thin-wall hemispherical shell under impact loading.They were subjected to impact loading of a drop hammer then the modes and features of their deformation were obtained in all the cases.Numerical simulations were done using ANSYS and LS-DYNA,then the deformation and energy absorption of three kinds of hemispherical shells were obtained.Numerical results showed that the concave deformations with a style of mirror-reflection appear in the single-layer empty hemispherical shell due to impact loading;for the single-layer fluid-filled hemispherical shell,due to the action of liquid inside,there is a larger transition zone on the edge of its concave deformations,if the impact energy is sufficient,the concave edge is made to be flat by the hammer;the single-layer empty hemispherical shell has a better capability of energy absorption,but its vertex displacement is bigger,so the effective protection space in it decreases;the double-layer liquid-filled hemispherical shell can absorb most of impact energy with smaller deformations,a certain protection space can be formed in it;the energy absorption and deformations of the single-layer liquid-filled hemispherical shell are similar to those of the double-layer liquide-filled hemispherical shell.