Development and verification of tritium transport code based on RELAP5/ MOD3.3 with generic model towards COOL blanket

Tritium evaluation is a critical issue in fusion reactors. For the tritium self-sufficiency and safety concern, it is crucial to develop tritium analysis techniques to study its behavior in various conditions including steady states and dynamic states. The supercritical CO2 cOoled Lithium-Lead (COOL) blanket is an advanced blanket concept for the Chinese Fusion Engineering Testing Reactor (CFETR) and one of its major functions is to realize tritium self-sufficiency. Therefore, it is necessary to conduct comprehensive analyses for design and optimization from the perspective of tritium transport. In this work, the tritium transport module is integrated inside RELAP5/ MOD3.3. Then the modified RELAP5 facilitates transient analyses to examine coupled thermal hydraulics and tritium transport responses. The code includes 1-D tritium permeation, tritium transport in fluid and tritium extraction, which are associated with thermodynamic parameters to cover the multi-physics processes of the COOL blanket. The modified RELAP5 is verified by the code-to-code benchmark. The results demonstrate the successful integration of the tritium transport capabilities in RELAP5. Furthermore, the code is applied to the heat exchanger and simplified PbLi loop to obtain tritium concentration to highlight its capability in both generic modeling and dynamic analysis.