CFD analysis of flow distributions and pressure drops in the whole CFETR WCCB blanket module with different turbulence models

As a primary blanket candidate for CFETR（China Fusion Engineering Test Reactor）, the water-cooled ceramic breeder (WCCB) blanket is now attracting enormous attention owing to the admirable thermal hydraulic performance and experienced industrial base of pressurized water. To analyze the flow distributions and pressure drops in the designed WCCB blanket, three dimensional numerical simulation of the coolant flow in the whole WCCB module was conducted based on the computational fluid dynamics (CFD) method. The results demonstrate that the flow distribution is uniform in cooling plates (CPs), stiffening plates (SPs) and side walls (SWs), but is non-uniform in the first wall (FW) with the unevenness of mass flow rate in FW being about 30%. The maximal pressure drop is in the CPs caused by the long coolant channel and the frequent change of flow direction. The effect of turbulence models needs to be comprehensively studied due to structural complexity of the designed manifold. Sensitivity analysis of turbulence models shows that different turbulence models have little effect on the mass flux distributions in all parts of the blanket module. However, the deviation of pressure drops is notable as a result of different turbulence models. In addition, the current design of the blanket module needs to be optimized further because of the non-uniform flow distribution in FW.