DESI focal plate mechanical integration and cooling
DESI focal plate mechanical integration and cooling
复制标题
DESI 焦板机械集成和冷却
DOI：
10.1117/12.2232978
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发表时间：
2016
期刊：
影响因子：
--
通讯作者：
J. Silber
中科院分区：
文献类型：
--
作者：
A. Lambert;R. Besuner;T. Claybaugh;J. Silber
暗能量光谱仪（DESI）正在建设中，使用重子声学振荡技术测量宇宙的膨胀历史[1]。超过14000平方英尺的4000万个星系的光谱。将在实验寿命期间测量deg。KPNO Mayall望远镜的新主焦点校正器将为5000个光纤定位器提供光线。这些光纤依次为10台宽带光谱仪提供信号。本文介绍了DESI焦板的机械集成和热系统设计。DESI焦板由十个相同的瓣组件组成。每个花瓣包含500个机器人光纤定位器。每个花瓣都是一个完整的、独立的单元，独立于其他单元，具有集成的电源、控制器、光纤路由和冷却服务。该计划的主要优点是：（1）支持在原位安装和移除完整的瓣组件，而不干扰其他组件，（2）部件生产、组装站和测试程序是重复的和可并行的，（3）可以在早期建造和测试完整的全尺寸原型，（4）每个生产瓣可以作为完整单元进行测量和测试，在积分之前，从焦面处的光纤尖端到光谱仪处的光纤狭缝。十个瓣组件将安装在一个集成环中，该集成环安装在DESI校正器上。铝制集成环通过一个弯曲的钢制适配器连接到钢制校正器镜筒上，将焦板与热膨胀差隔离开来。通过对瓣组件进行传导冷却，使板级保持稳定。导向器和波前传感器（每个瓣片一个）将通过强制空气流进行对流冷却。热量将在十个液体冷却的冷板上从系统中移除，每个花瓣一个，在环境温度下操作。整个焦板结构被封闭在绝缘罩中，绝缘罩作为发热焦板组件和Mayall圆顶环境空气之间的热屏障，以保护视宁度[2]。
The Dark Energy Spectroscopic Instrument (DESI) is under construction to measure the expansion history of the Universe using the Baryon Acoustic Oscillation technique[1]. The spectra of 40 million galaxies over 14000 sq. deg will be measured during the life of the experiment. A new prime focus corrector for the KPNO Mayall telescope will deliver light to 5000 fiber optic positioners. The fibers in turn feed ten broad-band spectrographs. This paper describes the mechanical integration of the DESI focal plate and the thermal system design. The DESI focal plate is comprised of ten identical petal assemblies. Each petal contains 500 robotic fiber positioners. Each petal is a complete, self-contained unit, independent from the others, with integrated power supply, controllers, fiber routing, and cooling services. The major advantages of this scheme are: (1) supports installation and removal of complete petal assemblies in-situ, without disturbing the others, (2) component production, assembly stations, and test procedures are repeated and parallelizable, (3) a complete, full-scale prototype can be built and tested at an early date, (4) each production petal can be surveyed and tested as a complete unit, prior to integration, from the fiber tip at the focal surface to the fiber slit at the spectrograph. The ten petal assemblies will be installed in a single integration ring, which is mounted to the DESI corrector. The aluminum integration ring attaches to the steel corrector barrel via a flexured steel adapter, isolating the focal plate from differential thermal expansions. The plate scale will be kept stable by conductive cooling of the petal assembly. The guider and wavefront sensors (one per petal) will be convectively cooled by forced flow of air. Heat will be removed from the system at ten liquid-cooled cold plates, one per petal, operating at ambient temperature. The entire focal plate structure is enclosed in an insulating shroud, which serves as a thermal barrier between the heat-generating focal plate components and the ambient air of the Mayall dome, to protect the seeing[2].