典型折叠充气管的建模修正与展开仿真

Modeling Modification and Deployment Simulation of Inflatable Tube with Typical Folded Configurations

本文分别研究了Z形、卷曲形、嵌套形折叠充气管的有限元建模方法。折叠充气管在进行有限元建模时,由于折叠部位内外层蒙皮的长度不一致给模型带来几何误差。不同的折叠方式建模技巧各不相同,引入的误差量也各不相同,本文着重分析了Z形折叠和卷曲形折叠建模所产生的几何误差,并提出了相应的修正方法。针对三种典型折叠方式,建立了相应的有限元模型,并应用控制体积算法实现了充气管的展开仿真。仿真结果验证了修正方法的有效性。增加尼龙粘扣是实现长卷曲折叠管的有控制展开的有效手段之一,本文采用失效连接来模拟尼龙粘扣的作用,比较了有、无尼龙粘扣的卷曲管的展开过程。仿真结果表明采用尼龙粘扣既不会明显带来充气管额外质量和刚度的增加,又可保证展开次序和展开方向的可控性,改善了展开过程的稳定性。

Finite element models of three typical folded inflatable tubes,respectively named Z-folded,telescopicallyfolded,and coiled configurations,are established,and a control volume method is applied to simulate the deployment process.Different folded configurations can introduce different geometry errors during the finite element modeling of inflatable tubes.Reasons of the modeling geometry errors due to Z folding and coiled folding,and modification methods of geometry error for every folding configuration are presented in this paper.The comparison of simulation results shows that the presented modeling modification method can reduce the effect of geometry errors on simulation results.Finally,a finite element model of a coiled tube with a Velcro strip is discussed,and the Velcro strips are modeled as breakable joints between nodes belonging to different skin layers.The numerical simulation results of coiled tube with or without Velcro strip indicate that Velcro strip can improve the deployment stability of coiled tube,and it is feasible that using the Velcro strip to control the deployment of a long coiled tube,and its additional stiffness and mass is negligible.