Study on the effects from spacer wires on coolant flow within a CiADS fuel assembly.

• The empirical formula of Remhe and Novendstern can better evaluate the pressure drop along the rod bundle section of the fuel assembly in CiADS. • The mixing effect of spacer wires may enhance the LBE flow velocity and heat transfer coefficiency. • The winding pattern has a noticeable effect on the temperature distribution at the assembly outlet. • When the winding angle of spacer wires is set at 30°, the temperature distribution at the outlet of the assembly will be more uniform. Spacer wires are frequently applied as the positioning components of fuel rods in lead-based fast reactors. It is extremely important to carry out the research of the impacts from spacer wires on coolant flow within fuel assemblies, and therefore the safety performances of reactor core. In this paper, the open source CFD calculation software OpenFOAM was adopted to perform the refined numerical simulation on the rod bundle of the fuel assembly in CiADS. The results show that spacer wires will increase the pressure drop along the rod bundle section of the fuel assembly. The empirical formula of Remhe and Novendstern can better evaluate the pressure drop along the rod bundle section of the fuel assembly in CiADS. The mixing effect of spacer wires may enhance the LBE flow velocity and heat transfer coefficiency. The winding pattern has a noticeable effect on the temperature distribution at the assembly outlet. When the winding angle of spacer wires is set at 30°, the temperature distribution at the outlet of the assembly will be more uniform. [ABSTRACT FROM AUTHOR]