Abstract:

In the present work, tritium permeation issue of gas injection system (GIS) in DEMO were focused. Based on the reactor core parameters of Chian Fusion Engineering Test Reactor (CFETR) and referring to accumulated experience of GIS design in ITER, preliminary pipes layout of DEMO GIS was performed. Steady-state tritium gas pressure drop calculation along the pipes and pump head request to the fuel storage and delivery system were made on the basis of the GIS’s structure layout. Tritium permeation under corresponding pump head was calculated at the same time. According to the calculation results, gravitational potential is the main determinant to pressure drop in pipe flow and the tritium permeation in GIS is of little amount to the whole tritium cycle in the case negative pressure. So this work offers related parameters to tritium self-sufficiency issues in DEMO, and also lays the foundation for further optimization of GIS’s structure layout.

Key words: DEMO, Gas injection system, Pressure drop calculation, Tritium permeation

摘要：

以中国聚变工程实验堆(CFETR)的堆芯参数为例, 参照ITER 的相关工程设计，对聚变示范堆(DEMO) 气体注入系统(GIS)作出了初步的管道布局考虑。基于此布局，计算了稳态运行下GIS 含氚管道气流压降，对燃料储存与输运系统的泵压头提出了要求，得出相应泵压头下GIS 的氚渗透量。计算结果表明，重力势是管道气流压降的主要原因，在负压情况下，GIS 的氚渗透对整体氚循环的影响不大。这为研究DEMO 的氚自持问题提供了相关参数，为GIS歧管布局的进一步优化奠定了基础。

关键词: 聚变示范堆, 气体注入系统, 压降计算, 氚渗透