内爆炸载荷下梯度泡沫铝夹芯管的动态响应

基于3D-Voronoi技术构建了泡沫铝芯层的三维细观有限元模型，对梯度泡沫铝夹芯管在内爆炸载荷下的动态响应进行了数值模拟。分析讨论了夹芯管结构内外管的壁厚、泡沫芯层的相对密度、芯层梯度分布等参数对夹芯管结构的抗爆性能与吸能性能的影响，并与无芯层的双层圆管进行了对比。结果表明：泡沫材料的相对密度可通过改变泡沫胞元大小和胞元壁厚进行调控，利用两种方式构建的夹芯管计算结果一致；保持内、外圆管总质量不变，增大内管壁厚可以有效减小外管的塑性变形，但会影响泡沫芯层的能量耗散；泡沫芯层的填充可以有效降低内管的塑性变形，正梯度泡沫铝夹芯管的抗爆性能优于均匀泡沫及负梯度泡沫夹芯管。

Dynamic response of sandwich tubes with graded foam aluminum cores under internal blast loading

Dynamic response of sandwich tubes subjected to blast loading is investigated numerically. The 3D-Voronoi technology is introduced to establish three-dimensional mesoscopic finite element model of aluminum foam. The influences of the thickness of inner and outer tubes, the relative density of foam core and the core gradient on the blast resistance and energy absorption of the sandwich tubes are analyzed and compared with the double circular tubes with air core. The results show that the relative density of foam materials can be controlled by changing the size and wall thickness of cell, and the calculation results of the sandwich tube constructed by two methods are consistent. The increase of the inner tube thickness can effectively reduce the plastic deformation of outer tube and weaken the energy absorption of foam core. Foam filling is of benefit to reduce the plastic deformation of inner tube and the blast resistance of positive gradient is better than that of negative gradient and uniform core.