激光辐照下高反射镜热变形问题的尺度律

Scaling law in thermal deformation of high reflecting mirror under laser irradiation

基于热力解耦的热弹性模型,采用常用假设,通过方程分析法,导出了激光辐照下高反射镜热变形问题的尺度律。同时,还发现了对同一模型,当其他条件不变时,变形、温升、应力与激光功率密度之间具有线性关系。数值结果证明了该问题尺度律的成立及线性关系的正确性。该结论是利用缩比模型研究大尺寸反射镜在激光辐照下的热变形问题的依据,且为解决缩比模型设计、辐照条件设计和模型实验数据反推到原型等相关问题提供了参考准则。

Based on the thermal elastic model with thermal-mechanical uncoupling approximation and commonly-used assumptions, the scaling law in thermal deformation of high reflecting mirror under laser irradiation is obtained by equation analysis. For the same model, displacement, temperature rise, stress and strain change linearly with laser power density. The numerical results are consistent with the theory. The conclusions lay the foundation for using scaled small model to investigate the thermal deformation of large-size mirror under laser irradiation, and provide specific guidelines for the model designing and transforming experiment results to the prototype.