Abstract One of the main challenges in the roadmap to the realization of fusion energy is to develop a heat and power exhaust system able to withstand the large loads expected in the divertor of a fusion power plant. The challenge of reducing the heat load on the divertor targets is addressed, within the mission 2 ‘Heat-exhaust systems’, through the investigation of divertor configurations alternative to the standard Single Null (SN), such as the Snowflake (SF), Double Null (DN), X and Super-X (SX) divertors. This paper focuses on a preliminary engineering assessment of the alternative configurations proposed for the EU DEMO reactor. Starting from the description of the optimized plasma shape developed for each configuration, the 3D geometrical description of the Magnet System and of the main Mechanical Structures (Vacuum Vessel and in-vessel components) is presented. Based on the 3D geometry, the compatibility of the location and dimensions of ports with Remote Maintenance needs is discussed and possible design optimizations are proposed both for the Magnets system and the mechanical structures design. Finally, the various configurations are compared with regard to the engineering and feasibility aspects.

中文翻译：

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EU-DEMO 替代磁性偏滤器配置的初步工程评估

摘要 实现聚变能路线图中的主要挑战之一是开发一种能够承受聚变发电厂偏滤器中预期大负荷的热电排放系统。在任务 2“排热系统”中，通过研究替代标准单空 (SN) 的偏滤器配置，例如雪花 (SF)、双Null (DN)、X 和 Super-X (SX) 偏滤器。本文重点介绍为欧盟 DEMO 反应堆提议的替代配置的初步工程评估。从为每种配置开发的优化等离子体形状的描述开始，介绍了磁体系统和主要机械结构（真空容器和容器内组件）的 3D 几何描述。基于 3D 几何，讨论了端口的位置和尺寸与远程维护需求的兼容性，并为磁铁系统和机械结构设计提出了可能的设计优化。最后，在工程和可行性方面比较了各种配置。