为了研究空间热载荷对星载天线刚柔耦合多体系统的扰动,根据抛物反射面几何特征,采用壳体单元有限元离散化法,并考虑壳体厚度方向上的温度变化,建立了有限元列式的热传导方程；引入与应变能有关的耦合项,利用拉格朗日法推导了星载天线系统的大范围刚柔耦合动力学方程,研究了温度载荷对星载天线多体系统的动力学特性影响.仿真结果表明:空间热效应引起了动态的温度载荷,与结构变形发生耦合,诱发耦合颤振,加剧柔性反射面的弹性振动,造成卫星姿态和天线指向的扰动,严重影响了星载天线的指向精度.结论对星载天线指向精度的分析与控制具有重要的理论价值及工程实际意义.%The rigid-flexible dynamics of a satellite antenna system considering thermal load was studied under space environment. According to geometric characteristics of a parabolic antenna reflector, the temperature function in one element along its thickness direction was built for shell structures, and the finite element forms for heat conduction equations were derived. Then, the coupling terms related to strain energy were introduced. By using Lagrange's equations, the rigid-flexible coupling dynamic model of a freely floating satellite antenna was deduced under the large-scale motions. Therefore, the influence of the heat effect on the coupling performance of the satellite antenna system was studied numerically. The result showed that the temperature gradient induces vibration of flexible reflector to produce its elastic deformation; furthermore, its elastic vibration is aggravated to lead to deviations of satellite base attitude and disturbances of antenna pointing; thus, the satellite antenna pointing accuracy is seriously affected. The above conclusions had an important academic value and engineering significance.
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