Abstract The paper presents a conceptual design and its structural verification of the cryostat for the DEMOnstration Fusion Reactor (DEMO). The cryostat is a large pressure vessel providing the vacuum required to operate the superconducting coils at cryogenic temperatures. Cryostats of existing machines typically are cylindrical and self-support the external pressure. In a nuclear machine, like DEMO, a massive bioshield will enclose the reactor providing radiological protection to maintenance areas in the primary building. The proposed design makes use of the bioshield to support the cryostat which allows substantially reducing the amount of steel needed for its construction. The cryostat is a conventional pressure vessel and designed according to ASME VIII, Div. 2. Linear and nonlinear structural and thermal-structural FEM assessments show that the proposed conceptual cryostat design provides both, the required membrane strength to withstand the external pressure as well as the required flexibility to allow the thermal contraction in case of a loss of vacuum event causing the cryostat to cool down. However, the relatively thin shell is not capable of bearing any significant internal overpressure. Therefore, a rupture disk in the cryostat to release Helium into the building in case of large internal leaks of liquid Helium is required.

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用于 DEMO 托卡马克的非自支撑低温恒温器的设计和验证

摘要 本文介绍了演示聚变反应堆 (DEMO) 低温恒温器的概念设计及其结构验证。低温恒温器是一个大型压力容器，提供在低温下运行超导线圈所需的真空。现有机器的低温恒温器通常是圆柱形的，并自支撑外部压力。在像 DEMO 这样的核机器中，一个巨大的生物防护罩将包围反应堆，为主要建筑物的维护区域提供辐射保护。提议的设计利用生物屏蔽来支撑低温恒温器，从而大大减少其构造所需的钢材量。低温恒温器是一种传统的压力容器，根据 ASME VIII, Div. 设计。2. 线性和非线性结构和热结构 FEM 评估表明，所提出的概念性低温恒温器设计既提供了承受外部压力所需的膜强度，也提供了所需的灵活性，以在真空事件丢失导致热收缩的情况下允许热收缩。低温恒温器冷却。然而，相对薄的壳不能承受任何显着的内部过压。因此，需要低温恒温器中的爆破片将氦气释放到建筑物中，以防出现大量液氦内部泄漏。相对较薄的外壳无法承受任何显着的内部超压。因此，需要低温恒温器中的爆破片将氦气释放到建筑物中，以防出现大量液氦内部泄漏。相对较薄的外壳无法承受任何显着的内部超压。因此，需要低温恒温器中的爆破片将氦气释放到建筑物中，以防出现大量液氦内部泄漏。