圆形太阳同步轨道卫星的空间热环境分析

近年来得到广泛应用的微小型卫星大多运行于圆形的太阳同步轨道，空间外热流的计算对卫星热控制系统的设计至关重要。分析了圆形太阳同步近地轨道受太阳照射的特性，建立了运行于圆形太阳同步轨道的三轴稳定的长方体卫星的外热流模型，归纳了太阳辐射热流、地球反照热流和地球辐射热流的瞬时和周期平均值的计算公式，分析了外热流的变化规律。分析指出太阳同步轨道的受晒特性主要由轨道的降交点地方时决定，外热流中太阳辐射最强，地球反照最弱。通过计算卫星各表面的外热流特性，可选择合适的散热面及太阳能电池安装面。

Analysis on Space Thermal Environment for Circular Sun-Synchronous Orbit

The widely used micro-satellites in recent years usually run on a circular sun-synchronous orbit.The calculations of outer heat flux from space are extremely important for the design of thermal control system for a satellite.In the present paper,the solar illumination characteristics of circular sun-synchronous low-earth orbit are analyzed,and the external heat flux models are set up for a three-axis stabilized cubed satellite.The formula of instant and the period-mean heat fluxes for solar illumination,earth albedo and earth radiation are given subsequently,as well as their variation characteristics.It is indicated that the solar illumination of sun-synchronous orbit is mainly determined by local time of descending node,and the solar heat flux is the most while the earth albedo is the least.The suitable faces can be chosen for radiating surfaces or solar panel by computing the external heat flux of a satellite.