Research on Simulation Technology of Refrigerating Large Scale Super conducting Magnet System

制冷大型超导磁体系统仿真技术研究

• 批准号: 07555391
• 负责人: SATOH Sadao
• 金额: $ 4.86万
• 依托单位: National Institute for Fusion Science
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (A)
• 财政年份: 1995
• 资助国家: 日本
• 起止时间: 1995 至 1997
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-07555391/
• 关键词: Fusion; superconducting conductor; superconducting coil; accelerator; cryogenic system; cryogenic structure; liquid helium; super fluid helium; 超伝導マグネット; ヘリウム冷却システム; 熱負荷特性; クライオスタット

A sperconducting system used in magnetic confinement fusion devices should be kept at superconducting temperature while it is excited or should be cooled down initially from room temperature to 0.4 K massive support structures . The purpose of the research is to investigate an overall cryogenic characteristics of superconducting system coupled with helium refrigerator through applying various thermal loads artificially by a dummy heater system on a real refrigerator with which the real overall characteristics of superconducting system can be simulated precisely in wide range free of various constraints accompanied in a real system . During a first year of the research project we designed and fabricated a dummy heat load generator . Since the Helium refrigerator / liquefier of the Large Helical Device has a duty to refrigerate the largest superconducting system in the world at 0.4 K , it has also a world largest class capacity and efficiency . Therefore , a size of the dummy heater system was chosen as one thirds to that of LHD superconducting system . During next years several combined operation of dummy heater with refrigerator were made and an oscillatory instability in suprecritical helium lines was observed . Initially this was thought as instability due to a density / thermal wave propagation , however , the instability was removed mostly when a room temperature gas buffer vessel was installed on a line between room temperature compressor discharge and a cold J - T valve which isolates interference between pressure oscillation by compressor and the motion of pressure regulating valve . A computer program for initial cooling down of dummy heater and refrigerator system was developed of which technology can be applied directly to LHD superconducting cryogenic system .

磁约束聚变装置中使用的子导体系统在被激发时应保持在超导温度下，或者应首先从室温冷却到0.4K的大质量支撑结构。研究目的是通过在真实的制冷机上人为地施加各种热负荷，研究超导系统与氦制冷机耦合的整体低温特性，从而在大范围内精确地模拟出真实的超导系统的整体特性，而不受真实的系统的各种约束。在研究项目的第一年，我们设计和制造了一个虚拟的热负荷发生器。由于大型螺旋装置的氦制冷机/蒸发器有责任在0.4K下制冷世界上最大的超导系统，因此它也具有世界上最大的容量和效率。因此，虚拟加热器系统的尺寸被选择为LHD超导系统的尺寸的三分之一。在随后的几年中，进行了几次虚拟加热器与制冷机的联合运行，并观察到超临界氦线中的振荡不稳定性。最初，这被认为是由于密度/热波传播引起的不稳定性，然而，当室温气体缓冲容器安装在室温压缩机排放和冷J-T阀之间的管线上时，不稳定性大多被消除，该冷J-T阀隔离压缩机的压力振荡和压力调节阀的运动之间的干扰。编制了模拟加热器和制冷器系统初始冷却的计算机程序，该技术可直接应用于铲运机超导低温系统。

项目成果

Toshiyuki Mito et al.: "Cryogenic Control System For The Louge Helical Device"Proc. 16th Int. Cryogenic Engineering Conference. Part 1. 79-82 (1997)

Toshiyuki Mito 等人：“Louge 螺旋装置的低温控制系统”Proc。

Toshiyuki Mito et.al.: "Cryogenic Control System for the Large Helical Device"proc. 16th ICEC Kitakyusyu. 79 (1997)

Toshiyuki Mito 等人：“大型螺旋装置的低温控制系统”proc。

Sadao Satoh et al: "Desigu and Construction of Cryogenic Components for LHD"Proc. 16th Int. Cryogenic Engineering Conference. Part 1. 63-63 (1997)

Sadao Satoh 等人：“LHD 低温组件的设计和构建”Proc。

R. Maekawa et al.: "Study of Optimum Operating Condition for the Helium Refrigeration System for the LHD with a Dummy Load Apparatus"Proc. 16th Int. Cryogenic Engineering Conference. Part 1. 87-90 (1997)

R. Maekawa 等人：“带有假负载装置的 LHD 氦制冷系统最佳运行条件的研究”Proc。

Sadao Satoh et.al.: "Design and Construction of Cryogenic Components for LHD"proc. 16th ICEC Kitakyusyu. 63 (1997)

Sadao Satoh 等人：“LHD 低温组件的设计和构造”proc。