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NASA 韦布团队 2024 年 8 月

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隔热别用厚板

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护住极冷红外望远镜

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靠五层隔开的薄膜

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镜面和传感器够冷才看得见微弱红外

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遮阳罩挡住太阳、地球、月球和航天器的热

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层间真空，接触传导断了

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但真空不等于没有辐射

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保温瓶也要镀银挡辐射

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敞开的缝、膜的形状与间隔

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让热每下一层从侧边辐射一次

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越靠近望远镜越冷

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热被甩向两侧

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厚板没出口，热沿实心材料直达冷面

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厚度不是防线反倒成了导热桥

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膜是 Kapton 加铝涂层

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最热两层加处理硅

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是反射耐热，不是实体金属板

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层数非越多越好

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NASA 建模比过二到七层

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多一层多份重量

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少一层不够冷

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五层留冗余，破一层其余挡热

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是冷却、冗余与重量、复杂度的折中

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把热一次次引向两侧，非偷工减料

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下次看遮阳罩展开，数数五道缝