Oxygen concentration control is the most promising technique to solve the corrosion problem in LFRs. A numerical study on the oxygen transport characteristics in the solid-phase oxygen control is carried out in this paper. The geometry is created using the Discrete Elements Method (DEM). The mass transfer and boundary layer theory is adopted to model the PbO dissolution process. The dissolution rate, mass transfer coefficient, and Sherwood number are then calculated for different flow conditions. The simulation models are validated by the experimental data obtained in the CRAFT experiment by SCK·CEN with a deviation of 15%. Based on the validated models, the parameter sensitivity analysis is carried out. The results show that the mass transfer coefficient does not change with inlet concentration, increases with the increase in mass flow rate and temperature. Finally, an oxygen mass transfer relation for a packed bed of PbO spheres in flowing Lead-bismuth eutectic (LBE) considering the temperature dependence and velocity dependence separately is obtained based on the numerical results. The relation could be used in a one-dimensional analysis code for the design of an LBE-cooled system with an oxygen control system.

氧气浓度控制是解决LFR腐蚀问题最有希望的技术。本文对固相氧气控制中的输氧特性进行了数值研究。使用离散元素方法（DEM）创建几何。采用传质和边界层理论对PbO的溶解过程进行建模。然后针对不同的流动条件计算溶出度，传质系数和舍伍德数。通过SCK·CEN在CRAFT实验中获得的实验数据验证了仿真模型的正确性，偏差为15％。在验证的模型的基础上，进行了参数敏感性分析。结果表明，传质系数不随进口浓度而变化，随着质量流量和温度的增加而增加。最后，基于数值结果，获得了流动的铅-铋共晶（LBE）中PbO球填充床的氧传质关系。该关系可以在一维分析代码中用于设计带有氧气控制系统的LBE冷却系统。