基于四方程模型的LBE环管湍流换热数值研究

为计算液态铅铋（LBE）在环管内不同加热环境下的湍流换热，基于开源计算流体力学程序OpenFOAM开发了四方程模型求解器4eqnFoam。将LBE在平板和圆管内的预测结果与直接数值模拟结果和实验结果进行对比，验证了求解器的有效性。基于该求解器，分别计算了LBE在外壁绝热内壁加热以及内外壁面等热流加热环管内不同雷诺数下的湍流换热量。结果表明：随着雷诺数的增加，两种加热条件下的无量纲温度脉动、雷诺热流、湍流热扩散作用增大，而平均湍流普朗特数减小；当雷诺数增加到一定程度时，平均湍流普朗特数变化不明显。基于4eqnFoam求解器，可为计算LBE热工水力现象提供更多参考。

Numerical Study on Turbulent Heat Transfer of LBE in Annulus Based on Four-equation Model

To calculate the turbulent heat transfer of liquid lead?bismuth (LBE) under different heating conditions in an annulus, a four?equation model solver 4eqnFoam was developed based on the open?source computational fluid dynamics program OpenFOAM. The prediction results of LBE in a plane and a pipe were compared with the results of direct numerical simulation and experiment, and the effectiveness of the solver was verified. Based on the solver, the turbulent heat transfers of LBE at different Reynolds numbers in an annulus with adiabatic outer wall and heated inner wall and an annulus with equal heat flux on the inner and outer wall were calculated respectively. The results show that with the increase of Reynolds numbers, the dimensionless temperature fluctuation, Reynolds heat flux, and turbulent heat diffusion of LBE in the annulus increase, while the mean turbulent Prandtl number decreases. When the Reynolds number increases to a certain extent, the mean turbulent Prandtl number does not change significantly. Based on the 4eqnFoam solver, more references can be provided for the calculation of LBE thermal?hydraulic phenomena.