平流层软式飞艇的多参数敏感性分析

Multi-parameter sensitivity of stratosphere non-rigid airship

为研究各参数对平流层软式飞艇力学性能的影响,采用基于拉丁超立方抽样的全局灵敏度分析方法——Sobol’法对某平流层软式飞艇进行了多参数敏感性分析,统计分析了材料参数、荷载参数及外形参数对结构静力性能及自振特性的总体敏感度;采用单参数变化的思想,研究了主要敏感参数对结构最大等效应力、最大变形及自振频率的影响规律.结果表明:对于结构静力性能,蒙皮面密度及吊索相关参数的敏感度可以忽略不计;对于自振特性,吊索相关参数的敏感度可以忽略不计;增加长细比、蒙皮厚度、蒙皮弹性模量或减小径向最低点压差值可以有效地提高结构的局部力学性能;增加径向最低点压差值或减小长细比可有效提高结构腰部抗变形能力.

In order to study the influence of parameters on mechanical performance of stratosphere non-rigid airship,Sobol＇method which is a global sensitivity analysis method based on the Latin hypercube sampling is used for analyzing the multi-parameter sensitivity. The global sensitivities of material parameters,load parameters and configuration parameters to the static performances and the vibration characteristics are analyzed. The influence laws of the main sensitive parameters on the maximum equivalent stress,the maximum deformation and frequencies are analyzed based on the single parameter changing. The research indicates that the sensitivities of membrane surface density and sling parameters to the static performances can be neglected. The sensitivities of sling parameters to the vibration characteristics can be neglected. Local mechanical properties can be effectively improved by increasing slenderness ratio,membrane thickness,membrane elastic modulus or decreasing pressure at the radial lowest point.The anti-deformation capacity of waist can be effectively improved by increasing the pressure at the radial lowest point or decreasing slenderness ratio.