空间结构热变形的子域摄动随机有限元解法

Perturbation based sub-domain stochastic finite element method for analyzing thermal deformations of space structures

针对航天器大型柔性附件在轨运行时的热变形问题,并考虑到结构参数有较大的随机性,提出了一种求解大参数扰动下结构随机热变形的有限元方法。该方法首先把随机变量的定义域划分成一系列子域,然后基于摄动有限元格式求解出各子域上的随机热变形,并由此构造出结构的整体随机热变形。由于随机变量的变异系数在每个子域上足够小,所以该方法可以精确地计算大参数扰动问题。

A stochastic finite element method（FEM） was developed to analyze the thermal deformations of large flexible appendages on spacecraft.The model includes consideration of the large uncertainties of the structural parameters.This method first subdivides the definition domains of the random variables into sub-domains and then reconstructes the global thermal deformation from the deformation obtained on each sub-domain through the perturbation based FEM.Since the parameter uncertainties are small enough in each sub-domain,problems with large uncertainties can be accurately solved by this method.