Adiabatic demagnetisation refrigerators for future sub-millimetre space missions
Adiabatic demagnetisation refrigerators for future sub-millimetre space missions
复制标题
用于未来亚毫米太空任务的绝热退磁制冷机
DOI：
10.1007/bf00751272
复制
发表时间：
1995
影响因子：
10.3
通讯作者：
A. Smith
中科院分区：
文献类型：
--
作者：
I. Hepburn;I. Davenport;A. Smith
下一代亚毫米空间飞行任务将需要能够为测辐射热探测器提供100 mK及以下热负荷汇的空间制冷。绝热退磁制冷（ADR）是一种不受重力影响的实验室制冷方法，是一种适合于空间应用的技术。我们通过考虑3个盐丸制冷机而不是经典的单盐丸制冷机设计，证明了在高磁场（6 T）和<2 K环境下的空间禁止实验室ADR特性（由液体4He浴提供），同时保持足够的低温保持时间和短的再循环时间。由钆镓石榴石（GGG）组成的附加盐丸提供中间冷却阶段，使得能够从由单个4K机械冷却器提供的4K环境进行操作，从而提供无消耗的操作。这种ADR可以在低至1特斯拉的磁场下工作，允许使用高温，机械冷却的超导磁体，因此有效地消除了淬火的风险。我们讨论了将保持时间从3小时增加到40和80小时之间的可能性，对于所提出的模型，加上将盐丸的数量减少到两个，我们认为，设想的ADR所需的技术进步是最小的，并得出结论，这种ADR提供了一个长的轨道寿命，无消耗品，高效率的毫开尔文冷却手段，需要相对较少的实验室开发。
Space worthy refrigeration capable of providing a 100 mK and below heat load sink for bolometric detectors will be required for the next generation of sub-millimetre space missions. Adiabatic demagnetisation refrigeration (ADR), being a gravity independent laboratory method for obtaining such temperatures, is a favourable technique for utilisation in space.We show that by considering a 3 salt pill refrigerator rather than the classic single salt pill design the space prohibitive laboratory ADR properties of high magnetic field (6 Tesla) and a<2 K environment (provided by a bath of liquid4He) can be alleviated, while maintaining a sufficient low temperature hold time and short recycle time. The additional salt pills, composed of Gadolinium Gallium Garnet (GGG) provide intermediate cooling stages, enabling operation from a 4 K environment provided by a single 4 K mechanical cooler, thereby providing consumable free operation. Such ADRs could operate with fields as low as 1 Tesla allowing the use of high temperature, mechanically cooled superconducting magnets and so effectively remove the risk of quenching.We discuss the possibility of increasing the hold time from 3 hours, for the model presented, to between 40 and 80 hours, plus reducing the number of salt pills to two, through the use of a more efficient Garnet.We believe the technical advances necessitated by the envisaged ADRs are minimal and conclude that such ADRs offer a long orbital life time, consumable free, high efficiency means of milli-Kelvin cooling, requiring relatively little laboratory development.