祝融号火星车纳米气凝胶隔热装置设计及应用

Design of nano-aerogel thermal insulation device and its application in Zhurong Mars Rover

针对火星表面低温大气环境下多层隔热组件隔热性能大幅衰减、不能满足火星车保温需求的难题,提出了一种新型、高效、轻质纳米气凝胶隔热装置设计方法,采用在真空和火星大气环境下导热率极低的纳米气凝胶为隔热材料,通过基于低导热复合材料的盒盖式局部支撑封装、气凝胶与结构间填充缓冲泡沫进行多余物过滤、铺设反射屏进行辐射漏热隔离、开设排气孔等设计方法,解决了力学性能增强、多余物控制、辐射漏热隔离、快速泄复压等工程应用难题,成功完成纳米气凝胶在祝融号火星车的工程应用。地面试验测试结果表明,1400 Pa、二氧化碳气氛、25℃时纳米气凝胶隔热装置总导热系数低至0.0080 W/(m·K),有力保障了祝融号火星车舱内设备在零加热功率补偿条件下在轨温度仍处于允许范围内。火星车纳米气凝胶隔热装置总质量为5.95 kg,仅占火星车总质量的2.5%。

The insulation performance of the multi-layer insulation module degrades sharply in the low temperature atmosphere on the surface of Mars,so that the need for insulation of the Mars rover cannot be satisfied.The design method of a new,efficient and lightweight nano-aerogel thermal insulation device is proposed.Nano-aerogel,which has extremely low thermal conductivity in the vacuum and Mars atmosphere,is used as the insulation material.Using the methods such as box covering and local supporting based on low thermal conductivity composite materials,filling the space between nano-aerogel and the architecture with buffer foam to filter redundancy,laying the reflector to insulate radiation heat leakage and opening vent holes,the problems in application such as mechanical property enhancement,redundancy control,radiation heat leakage insulation,and rapid air entry and exit are solved.Nano-aerogel is successfully applied in Zhurong Rover.The ground test results show that in 1400 Pa CO;atmosphere,the total thermal conductivity of the nano-aerogel insulation device is 0.0080 W/(m·K)at 25℃,which effectively ensures that the temperature of the equipment inside Zhurong Mars Rover is in the allowable range with zero compensation of heating power.The total weight of the nano-aerogel thermal insulation device is 5.95 kg,only 2.5%of the total weight of Zhurong Mars Rover.