有限元法分析空心后向反射器面形精度

Analysis of the surface form accuracy of hollow retro-reflector using finite element method

为了探索空心后向反射器在工作状态下光学特性的变化 ,通过运用有限元法和在DEC/ 5 0 0 0工作站上采用MSC/NASTRAN程序 ,研究了用三种不同性能材料制成的空心后向反射器在不同几何尺寸和不同支承点位置时 ,载荷与温度梯度对空心后向反射器面形精度的影响。分别得出了反射器工作面变形与载荷大小、材料性能、支承点位置、温度梯度的关系曲线。这些曲线表明 :在确定条件下的反射器有一最佳的支承点位置 ;材料性能中的弹性模量对面形精度的影响最为显著 ;面形精度与载荷大小、温度梯度基本上成线性关系 。

In order to probe the variation of hollow retro reflector's optical property under working state, research has been made to observe hollow reflector's (made of three kinds different material) surface form accuracy variation caused by different loading and temperature gradient under the condition of different dimensional size and different support point by using the method of finite element and program of MSC/NASTRAN at the DEC/5000 working station. Four different curve diagrams of working form accuracy versus loading, working form accuracy versus material performance, working form versus temperature gradient based on the above research are obtained respectively. The diagrams show that reflector under certain conditions has an optimum support point; modulus of elasticity has most remarkable influence on working form accuracy; both loading and temperature gradient are basically linear to working form accuracy and temperature gradient is the major factor that influences working form accuracy.