星载辐射计扫描镜太阳辐射热-结构建模与仿真

摘要

The solar-radiation disturbance exists in the optical payloads onboard the three-axis stabilized satellite platform.It leads to thermal distortion, which obviously affects the imaging quality of optical system.The approximate modeling technique of complex external heat flux was applied, as well as the multi-software-coupled finite element simulation.The thermal effect of the imager's scan mirror caused by solar radiation was researched, and compared under different thermal design conditions on the FY-4 imager.The optimal scheme of the thermal design of the scan mirror was obtained.The result shows that the thermal distortion is closely related to the thermal coating on the side and the back of the scan mirror.It is difficult to resolve the conflict between the temperature fluctuation and the thermal distortion if only using the thermal design method.It is necessary to improve the material of the scan mirror or adjust the optical-mechanical structure.%三轴稳定卫星平台搭载的光学有效载荷都存在午夜太阳辐射干扰问题,由此产生的热变形效应对光学系统的成像品质影响显著.采用复杂外热流近似建模技术,以及多软件耦合有限元仿真方法,以FY-4卫星的扫描辐射计为应用背景,研究了昼夜太阳辐射对星载辐射计扫描镜产生的热效应,并对不同热设计条件下的工况进行了对比分析.分析结果显示:扫描镜侧面及背面的热控涂层选取对其热变形有重要影响,但是仅仅通过热设计解决温度波动和热变形的矛质是不够的,需要通过改进扫描镜的材料和优化光机结构加以改善.