Primary heat transfer system design of the WCCB blanket for multiple operation modes of CFETR

•The WCCB blanket has been updated to fulfill 200 MW-1.5 GW FP of CFETR.•The WCCB PHTS consists of 2 independent CSs, one for FW, the other for BZ.•Main system components were designed in detail.•The WCCB PHTS was modeled using RELAP5.•Steady states were reached under 4 FP levels for two CSs.