考虑结构遮挡和地影效应的环形桁架天线轨道热分析

打开文本图片集

中图分类号：V19;V414 文献标志码：A

Abstract：As one of the deployable satelite antenna structures，the circular-truss antenna has a wide application prospect in high power satelite-borne antenna due to its advantages of large aperture，light weight， high capacity，good stiffness，and the fact that the total mass does not increase exponentially with the expanding aperture.The alternation of hot and cold environment in space and the inhomogeneity of temperature distribution can easily cause serious thermal vibration problems and even lead to the failure of a spacecraft.In this paper，an orbital solar radiation model is presented instead of the traditional ray projection method for calculating the shielding coeffcient between the internal components of a circular truss antenna.By this model，we obtained the effctive solar incident heat flux received by each truss element of the antenna under the combined action of the shielding effect between the antenna's internal components and theearth shadow efect.On this basis，the thermal radiation-conduction model of the circular truss antenna is established.Variations of the temperature field of the circular-truss antenna in orbit can be calculated through the thermal radiation-conduction model by submitting the effctive solar incident heat flux received by each truss element of the antenna obtained from the orbital solar radiation model.A numerical test is performed on a 40m -aperature circular-truss antenna.The results show that the temperature difference of each part of the antenna truss structure is large due to the mutual shielding effect between the internal components of the antenna，and the maximum value reaches about 270°C .What is more，the antenna will have arapid change in temperature when it enters or exits the earth shadow region.It should be noted that thelarge deformation and thermal vibration of the circular truss antenna may be caused by the drastic temperature change and the inhomogeneity of the temperature distribution.

Key words： circular truss antenna；orbital solar radiation model；structural shielding；earth shadow effect；shielding coefficient；effective heat flux；temperature field

因环形桁架天线具有诸多优点，如可实现口径大，展开口径范围为 6～150m ，质量轻、收纳率较高、刚度较好及总质量不随展开口径的增大而成倍增加等特点，是当前最具有应用前景的一种空间大型可展天线，受到了专业研究人员的极大青睐。（剩余8378字）