Thermal hydraulic characteristics of spiral cross rod bundles in a lead-bismuth-cooled fast reactor

The flow and heat transfer behavior of self-structured spiral cross rod bundles in lead-bismuth-cooled fast reactor is analyzed with CFD methods. A computational model of spiral-cross-section fuel rod was established, and the velocity and temperature fields in the triangular arrangement of the fuel rod were numerically simulated. Uniform circumferential distribution in the velocity and temperature contours of the coolant was observed, which was resulted from the strong mixing effect in the spiral structure. Such a structure could replace the function of the wrapping wire. The Reynolds number had an obviously effect to the velocity and temperature, while the contribution of heat flux is negligible. It was also found that the heat transfer characteristics of the fluid flow can be affected by the shape of the cross section and the pitch of the spiral cross rod, etc.

Automated summary

In this study, the flow and heat transfer behavior of self-structured spiral cross rod bundles in a lead-bismuth-cooled fast reactor were analyzed using CFD methods. The results showed that the spiral structure had a strong mixing effect, leading to a uniform circumferential distribution of velocity and temperature contours. The Reynolds number had a significant influence on velocity and temperature, while the contribution of heat flux was negligible. Additionally, it was found that the heat transfer characteristics of the fluid flow were affected by the shape of the cross section and the pitch of the spiral cross rod.