静轨空间遥感器反射式光栏数值研究

Numerical Simulation of Reflective Barriers for Space Remote Sensors in Geostationary Orbit

受地球静止轨道上的空间外热流影响,空间低温光学系统的传统遮光罩极易产生极端高温现象,该现象产生的高温红外辐射是空间低温光学系统内部背景辐射的主要来源。文章针对上述问题进行研究,利用反射式光栏遮光罩取代传统的遮光罩,在保留消除杂散光能力的同时,优化遮光罩的控温特性,使其处于较低的温度水平,降低光机系统的背景辐射。文章给出了基于椭球曲线和椭球-双曲曲线设计的两种反射式光栏的设计方案,针对地球静止轨道热环境及空间遥感器入光口的特点,建立了考虑加工精度和粗糙度的传统遮光罩和两种反射式遮光罩的仿真分析模型,并分析了不同时刻、不同光栏设计方案的遮光罩控温特性及背景辐射分布情况,为工程化应用提供参考。结果表明,椭圆双曲遮光罩具有更好的控温特性,但过高的粗糙度会产生杂散光,影响镜片温度。

Affected by the space heat flow in the geostationary orbit,the traditional sunshields of the space cryogenic optical system is prone to extreme high temperature phenomenon,and the high-temperature infrared radiation generated by this phenomenon is the main source of the internal background radiation of this system.This paper studies the above problems and replaces the traditional sunshields with a reflective-barriers-sunshields.While retaining the ability to eliminate stray light,the temperature control characteristics of the sunshields are optimized to keep it at a lower temperature level and to reduce the background radiation of the optomechanical system.This paper presents two design schemes of reflective diaphragms based on ellipsoid curve and ellipsoid-hyperbolic curve.According to the thermal environment of the geostationary orbit and the characteristics of the light entrance of the space remote sensor,a design scheme considering the machining accuracy and roughness is established.The simulation analysis model of the traditional sunshields and two kinds of reflective sunshields with different degrees is analyzed,and the temperature control characteristics and background radiation distribution of the sunshields at different times and different reflective barrier design schemes are analyzed to provide reference for engineering applications.The results show that the elliptical-hyperbolic barriers has better temperature control characteristics,but too high roughness will produce stray light and affect the lens temperature.