大型环形桁架天线进出地影期热致振动特性研究

Research on thermally induced vibration of large hoop truss antenna moving through earth's shadow

对一类装备大型环形桁架天线的航天器在轨环境下的热-结构耦合问题进行了研究.将结构应变考虑为热应变与弹性应变的线性叠加,引入了热-弹耦合的线性时变刚度,建立了环形桁架天线的索网-框架组合结构热-弹耦合动力学方程.考虑了航天器姿态角的变化以及航天器部件遮挡对各部件温度变化的影响,建立了时变温度场模型.将得到的温度场作为外载荷激励,分析了进出地影期温度变化对航天器结构热致振动的影响规律,研究结果显示在轨温度环境对该结构影响不大.对某型号航天器在轨数据进行了分析,验证了数值分析的有效性.

The coupled thermal-structural analysis of a spacecraft including a large hoop truss antenna in the on-orbital environment is studied.The structural strain is considered as the superposition of the thermal strain and the elastic strain.The thermo-elastic coupling equation of the cable-truss composited structure for the hoop truss antenna is established by introducing the thermo-elastic linear time-varying stiffness.The time-varying thermal field is modeled by considering the change of the attitude of the spacecraft and the influence of the spacecraft occlusion on the temperature changing of components.The obtained thermal field is used as the external load,and the influence of temperature changing when the spacecraft structure moves through earth＇s shadow on the thermally induced vibration of the structure is analyzed.The results show that the temperature environment on-orbit has little influence on the structure.The data of on-orbit of a spacecraft is analyzed,and the efficiency of the numerical analysis is verified.