炭/炭复合材料在空间光学遥感器热控制中的应用

提出在金属表面粘贴炭/炭复合材料来解决空间光学遥感器光机结构材料导热率低、温度梯度较大的问题.概述了炭/炭复合材料的基本特点并建立了钢板表面粘贴炭/炭复合材料的热传导数学模型.对钢板的裸板和单面分别贴0.5mm和2 mm复合材料的3种状态进行了理论分析与温度测试试验,获得了钢板在3种状态下的等效热导率.利用IDEAS-TMG有限元软件对模型进行了仿真分析并对钢板在上述3种状态下的传热性能进行了比较.对比结果显示,粘贴炭/炭复合材料能很好地改善钢板的传热性能.最后,将0.5 mm厚的炭/炭复合材料应用于低热导率的星敏感器安装支架(材料为TC4)的热控,并对星敏感器支架粘贴炭/炭复合材料前后两种情况进行了温度测试试验.试验结果显示,表面粘贴炭/炭复合材料后,星敏感器支架测点温差由28℃减小为5℃,提高了星敏感器支架温度均匀性,表明该措施对改善空间光学遥感器上低热导率结构件的温度梯度很有意义.

Application of carbon-carbon composites to thermal control of space optical instrument

In order to improve the thermal conductivity of materials and decrease the temperature gradient of a space optical remote sensor,the carbon-carbon composites were pasted on the metal surface.The characteristics of carbon-carbon composites were introduced and the heat transfer models of one bare steel plate and two pasted plates with carbon-carbon composites in the thicknesses of 0.5 mm and 2 mm respectively were established.The three heat transfer states of the steel plates were calculated and experimented,and their equivalent thermal conductivities were obtained.The models were simulated by using the finite element model IDEAS-TMG and the heat transfer properties of three kinds of plates mentioned above were compared.Results is shown that the carbon-carbon composites could improve the temperature uniformity of the plates.Finally,the carbon-carbon composites were applied to a TC4 star-tracker bracket of a star sensor,and the temperature difference between the assembly area and the radiator was tested.The tested results indicate that it is 28 ℃ and 5 ℃,respectively,for the bare bracket and the one with 0.5 mm-thick carbon-carbon composites on the inner and outer sides.The tested result illuminates that the thermal conductivity of the bracket of the star-tracker is improved and its temperature gradient is reduced effectively.This method could give some guidances and references for the thermal design of other space optical instruments with great temperature gradients.