Transient pressure analysis for china dual-function lithium lead test blanket system under in-box LOCA accident

When In-box LOCA accident happened in Dual-Function Lithium Lead Test Blanket System (DFLL TBS), high pressure helium gas injected into low-pressure Lithium Lead (PbLi) zone, which caused pressurization and threaten the integrity of structure. In this paper, the model of DFLL TBS was created by RELAP5. In-box LOCA was analyzed, and the key parameters included the position and size of rupture, the blasting pressure were performed sensitivity analysis. The results show that the pressure (8.0 MPa) of helium was exceeded in different locations of rupture, the peak pressure of inlet is 16.68 MPa, and outlet is 13.92 MPa. Peak pressure was increased by 0.97 MPa (outlet) and 1.68 MPa (inlet) respectively under 1 and 10 channel rupture. In order to reduce the peak pressure inside the blanket module, two expansion vessels (> 1.2 × 10^-2 m³) were installed near the inlet and outlet pipes of the blanket respectively. By installing key components near the expansion vessel in LLAS, key components could be protected from exceeding their pressure limits. (authors)