Abstract The control of tritium permeation through the structural materials of fusion reactors is an important safety issue, and because both deuterium and tritium are fuel constituents, the effects of isotopes have to be taken into account in permeation assessments. Although various mathematical models and experiments regarding hydrogen isotope permeation through metals have been carried out so far, there are still unresolved issues like those regarding synergistic isotope effects (by which an isotope influences the permeation of another isotope when multiple isotopes permeate simultaneously). Some controversial issues of other previous steady-state work have led us to set up a non-steady-state model for multi-isotope permeation in a surface-limited regime (SLR). The mathematical model and the results obtained by numerical simulation (which are published elsewhere) have shown that in contrast to some previous steady-state approaches, the permeation flux of a heavier isotope is not reduced by the presence of a lighter one; to the contrary, it is increased. This theoretical prediction has to be verified against experimental data, and this is the goal of future work. But, the differences between multi-isotope and single-isotope permeations are not so large, and some deviations of the experimental model from the assumptions of the theoretical model (like SLR, constant partial pressures in retentate, or vacuum on the permeate side) could affect the theoretical predictions or could lead to misinterpretations of the experimental data. Therefore, these kinds of deviations and their effects have been analyzed within this work with the aim of implementing, in the experimental model, appropriate measures to mitigate these undesirable effects. The conceptual design of the proposed experimental setup and a procedure for setting some key operating parameters (like flow rates and pressure of the purge gas) are also presented.

中文翻译：

---

多组分氢同位素通过金属渗透的非稳态模型的面向实验的分析

摘要 控制氚通过聚变反应堆结构材料的渗透是一个重要的安全问题，由于氘和氚都是燃料成分，在渗透评估中必须考虑同位素的影响。尽管迄今为止已经进行了关于氢同位素通过金属渗透的各种数学模型和实验，但仍然存在未解决的问题，例如协同同位素效应（当多种同位素同时渗透时，一种同位素会影响另一种同位素的渗透）。其他先前稳态工作的一些有争议的问题导致我们建立了一个非稳态模型，用于在表面限制机制 (SLR) 中进行多同位素渗透。数学模型和通过数值模拟获得的结果（已在别处发表）表明，与以前的一些稳态方法相比，较重同位素的渗透通量不会因较轻同位素的存在而降低；相反，它增加了。这一理论预测必须根据实验数据进行验证，这是未来工作的目标。但是，多同位素渗透和单同位素渗透之间的差异并不大，实验模型与理论模型假设的一些偏差（如 SLR、渗余物中的恒定分压或渗透侧的真空）可能影响理论预测或可能导致对实验数据的误解。所以，在这项工作中分析了这些类型的偏差及其影响，目的是在实验模型中实施适当的措施来减轻这些不良影响。还介绍了所提出的实验装置的概念设计和设置一些关键操作参数（如吹扫气体的流速和压力）的程序。