嫦娥五号水升华热排散系统月面运行特性分析

Work performance analysis on the Chang’e-5 lunar lander water sublimation heat dissipation system

针对嫦娥五号着陆器和上升器组合体(着陆上升组合体)在月昼高温环境下工作期间无法提供足够散热面的难题,利用水在真空下高效蒸发/升华带走热量的原理,构建了水升华热排散系统.其在嫦娥五号任务中实现了月面正常启动和稳定运行,月面工作期间散热量达到约400 W,相对误差小于6.7%,使着陆上升组合体在月面110℃~140℃的环境下工作期间系统温度降低了5℃~10℃,有效保障了着陆上升组合体月面工作期间各系统在适宜的温度下运行,支撑了探测器月面无人自动采样任务的成功实施,标志着我国自主研制的高温水升华热排散系统首次月面应用取得成功.

One of the challenges for Chang’e-5 unmanned lunar soil autosampling and return to Earth mission is that the lunar lander-ascender vehicle combination cannot provide effective radiation cooling in the high-temperature lunar surface environment.Hence,a water sublimation heat dissipation system(WSHDS) is proposed to dissipate the system waste heat and maintain the functioning of the lunar probe work at the appropriate temperature.The WSHDS takes advantage of the high latent heat absorption of the evaporation or sublimation of the consumable substance in the vacuum environment to cool down the spacecraft.In our previous researches,a series of technique obstacles was removed,and the way was paved toward a successful system that can function on the lunar surface.The WSHDS heat rejection capability was up to 400 W with an analysis error of less than 6.7% for working on the lunar surface.The lunar lander-ascender vehicle combination was cooled down by 5°C–10°C in the 110°C–140°C lunar environment.The excellent performance of the WSHDS highly supports the possibility of success of this unmanned lunar soil autosampling mission by maintaining the function of the lunar probe at a suitable temperature during the lunar day.This represents a milestone in the first success on the orbital application of the WSHDS.