高滑翔伞伞绳叉联结构优化设计

为获得翼伞伞绳最优叉联结构设计方案,文章提出了 1种高滑翔翼伞伞绳叉联结构的优化设计方法。首先,通过计算流体力学方法进行翼伞气动分析,确定最优气动性能时对应的伞绳安装角及翼伞伞衣气动载荷；然后,通过几何分析和受力分析,建立伞绳结点处的力系平衡方程及伞绳长度几何控制方程；最后,在满足伞绳结构安全的前提下,以伞绳总长度最小为优化目标,采用基于外罚函数和 Davidon-Fletcher-Powell(DFP)算法原理的优化算法获得不同约束力条件对应的翼伞伞绳叉联点位置方案。优化结果表明:与优化前叉联方案相比,该方法伞绳长度可减小 9.0%,阻力系数降低 8.8%。此外,通过增加伞绳受力约束,可实现翼伞滑翔性能的进一步提高。

Optimization Design of Split-Link Cord for High Gliding Parafoils

In order to obtain the optimal design of the split-link cord structure of the parafoil rope, an optimization method of split-link cord design for high gliding parafoils is presented. Firstly, computational fluid dynamics method and theoretical methods are used to analyze the aerodynamic performance of two-dimensional and three-dimensional para‐foils, respectively. The optimal cord installation angle is determined based on the optimal attack angle, where the best aerodynamic performance can be achieved. On this basis, the geometric analysis and mechanics analysis are performed to derive the equilibrium equations of cord mechanics and the equations of paracord length. Finally, the optimization algo-rithm based on the external penalty function method and Davidon-Fletcher-Powell algorithm (DFP) is established to deter-mine the optimal split-link cord design corresponding to different structure safety coefficients with the minimum cord length as the optimization objective under structure safety. The results show that the cord length and drag coefficient can be reduced by 9.0% and 8.8%, respectively, compared with the cord design by previous empirical method, which is con-vinced to improve the gliding performance of parafoils. In addition, the parafoil performance is able to be further im-proved by adjusting the structure safety limits.