Abstract Palladium alloy permeators are foreseen for the retrieval of hydrogen in the fusion fuel cycle of the European DEMO power plant. Driven by a pressure gradient, unburned fuel permeates through a thin-walled metallic membrane within the permeator while other gases cannot pass this barrier. With a theoretically unlimited selectivity with regard to nonhydrogenic species, a very high proportion of unburned fuel can be recovered in a continuous process from the exhaust gas and reused after a very short time. A potential candidate for the design of such a permeator consists of a tube (l = 500 mm, d = 10 mm) with a 125-μm-thick, self-supporting membrane made of a palladium-silver alloy all combined in the shape of a so-called finger-type design. A two-stage process then connects several of these permeators in parallel and in series to match the required throughput of DEMO during plasma operation at a given degree of separation. As the first design point in the scope of the current preconceptual design phase, a model was developed using the commercial software ASPEN Custom Modeler to estimate important parameters such as the tritium inventory and the scale of the permeator unit. How the hydrogen pressure profile is calculated over the length of a permeator using the Sieverts’ Law and the Finite Volume Method is thoroughly described. As a result, the integral performance of the combined permeators is presented as well as all important boundary conditions and assumptions that led to it. For the current DEMO baseline scenario, the total number of permeators of the abovementioned shape is found to be about 50.

中文翻译：

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EU-DEMO 燃料循环的渗透器模拟

摘要 钯合金渗透器可用于回收欧洲 DEMO 发电厂聚变燃料循环中的氢气。在压力梯度的驱动下，未燃烧的燃料通过渗透器内的薄壁金属膜渗透，而其他气体则无法通过该屏障。由于对非氢物质具有理论上无限的选择性，因此可以在连续过程中从废气中回收非常高比例的未燃烧燃料，并在很短的时间后重新使用。设计这种渗透器的一个潜在候选者包括一根管子（l = 500 mm，d = 10 mm）和 125 μm 厚的自支撑膜，由钯银合金制成，所有膜都组合成所谓的手指式设计。然后，一个两阶段过程将这些渗透器中的几个并联和串联连接，以匹配在给定分离度的等离子体操作期间所需的 DEMO 吞吐量。作为当前概念设计阶段范围内的第一个设计点，使用商业软件 ASPEN Custom Modeler 开发了一个模型来估算重要参数，例如氚库存和渗透器装置的规模。详细描述了如何使用 Sieverts 定律和有限体积方法在整个渗透器长度上计算氢气压力分布。因此，给出了组合渗透器的整体性能以及导致它的所有重要边界条件和假设。对于当前的 DEMO 基线场景，