相变致冷镜的有限元结构优化

Optimum design of phase-change cooling mirror's fabrication by finite element method

镜体的结构决定了相变致冷镜抑制腔镜在高能激光辐照下的热变形的效果。比较不同结构形式的相变致冷镜镜面热变形的有限元软件计算结果,并通过一阶非线性优化方法,得到较优的放射状结构:硅基基体外径80mm,厚度12.5mm,光斑直径40mm,吸收功率密度为79.58kW/m2,当其最优沟槽深度为9 9mm,宽度为0.4mm时,光照10s时镜面热变形达到最小值0.37μm。

The effect of the phase-change cooling mirror will depend on the fabrication. Compared to the different computing result through finite element method, the radialized shape is chosen to be the optimum design. For Si mirror, with 80 mm in diameter and 12.5 mm in depth, the optimum channel fabrication has the depth of 9.9 mm and width of 0.4 mm and the smallest thermal deformation is 0.37 μm after 10 s irradiation by a co-axial light whose diameter is 40 mm and net absorbing power density is 79.58 kW/m2.