临近空间超压气球结构多样性设计与仿真

Structure Diversity Design and Simulation of the Near Space Super Pressure Balloon

通过超压气球结构多样性设计来优化球体的承压能力是该领域的重要研究方向。超压气球柔性加强筋与柔性球膜的相对滑动和球膜间的自接触是典型的结构非线性问题,也是对超压气球建模实现有限元仿真验证的最大难点。对此,采用罚函数法成功实现加强筋与球膜的滑动接触与自接触,在此基础上建立了纵向筋欧拉体、菱形网欧拉体和南瓜形超压球三种结构的有限元模型。通过理论分析和仿真验证发现,铺设纵向加强筋或菱形网结构都能改善欧拉体的应力分布,减小球膜应力,提升球体承压能力;并且加强筋数量越多,这种改善作用越明显,承压能力越好。当加强筋数量相等时,南瓜形超压球的承压能力优于纵向筋欧拉体和菱形网欧拉体。因此,南瓜形超压气球是目前该领域最主流的球体结构设计方式。

Optimizing the pressure bearing capacity of super pressure balloons through the structural diversity de sign is an important research in this field.The relative sliding between the tendons and the flexible membrane and the self-contact between the spherical membranes are typical structural nonlinear problems.It is also the biggest diffi culty for finite element simulation of super pressure balloon.Penalty method was used to successfully realize the slid ing contact and Self-contact of tendons and membranes.Based on this,three kinds of finite element models inclu ding longitudinal-tendons Euler-sphere,diamonds Euler-sphere and pumpkin super pressure balloon were estab lished.Through the theoretical analysis and simulation comparison,the laying of longitudinal tendons or diamond-shaped net structures can improve the stress distribution of the Eulerian body,reduce the membrane stress,and im prove the pressure bearing capacity.And the greater the number of tendons is,the more obvious the improvement effect and the better the pressure bearing capacity.When the number of tendons is equal,the pressure bearing capac ity of pumpkin superpressure balloon is the best.Therefore,pumpkin super pressure balloon is the most popular sphere structure design method in this field.