Numerical simulation of three-dimensional flow and heat transfer characteristics of liquid lead–bismuth
Shaopeng He, Mingjun Wang, Jing Zhang, Wenxi Tian, Suizheng Qiu, G.H. Su
Abstract
Liquid lead-bismuth cooled fast reactor is one of the most promising reactor types among the fourth-generation nuclear energy systems . The flow and heat transfer characteristics of lead-bismuth eutectic (LBE) are completely different from ordinary fluids due to its special thermal properties , causing that the traditional Reynolds analogy is no longer recommended and appropriate. More accurate turbulence flow and heat transfer model for the liquid metal lead-bismuth should be developed and applied in CFD simulation . In this paper, a specific CFD solver for simulating the flow and heat transfer of liquid lead-bismuth based on the k - ε - k θ - ε θ model was developed based on the open source platform OpenFOAM . Then the advantage of proposed model was demonstrated and validated against a set of experimental data. Finally, the simulation of LBE turbulent flow and heat transfer in a 7-pin wire-wrapped rod bundle with the k - ε - k θ - ε θ model was carried out. The influence of wire on the flow and heat transfer characteristics and the three-dimensional distribution of key thermal hydraulic parameters such as temperature, cross-flow velocity and Nusselt number were studied and presented. Compared with the traditional SED model with a constant Pr t = 1.5 or 2.0, the k - ε - k θ - ε θ model is more accurate on predicting the turbulence flow and heat transfer of liquid lead-bismuth. The average relative error of the k - ε - k θ - ε θ model is reduced by 11.1% at most under the simulation conditions in this paper. This work is meaningful for the thermal hydraulic analysis and structure design of fuel assembly in the liquid lead-bismuth cooled fast reactor.