平行光管主反射镜组件的非线性有限元分析

为了提高对光学仪器中光机结构分析的精度,引入了非线性分析方法,用非线性有限元法研究了某平行光管主镜组件存在的非线性问题。介绍了产生结构非线性的主要来源,并在接触理论的基础上对主反射镜组件进行了合理的有限元建模。采用接触非线性分析方法对螺钉预紧时反射镜的响应及在自重和温度载荷作用下反射镜的变形进行了分析。将线性和非线性分析结果与实际结果进行了对比,结果表明,采用接触非线性分析方法对反射镜组件进行工程分析减小了分析误差。因此,在工程分析中,对某些接触部位采用非线性分析方法可以提高分析精度,得到的结果更加符合实际。

Nonlinear analysis of primary mirror subassembly for collimator based on finite element method

To improve the analysis accuracy for the optical mechanical structure of a optical system, a nonlinear analysis method is introduced and then a nonlinear Finite Element(FE)analysis is applied to analysis of the mechanical model of a primary mirror subassembly. The main source for structural nonlinearity is summarized, and a FE model for the primary mirror subassembly of a collimator is established on the basis of contact theory. The mirror response based on bolt contact and the mirror deviation based on gravity and temperature loads are analyzed by contact nonlinear analysis method. Using a practical mesuring result, the linear and nonlinear methods are compared, and it is included that the contact nonlinear analysis indeed reduces the analysis error. Therefore, nonlinear analysis can improve the analysis accuracy and obtain the results which are close to that in real system of engineering analysis.