流化床-化学气相沉积颗粒包覆过程数值模拟  

Numerical simulations of particle coating using the fluidized bed-chemical vapor deposition method

作　　者：陈猛 陈昭 刘荣正[1] 刘兵[1] 邵友林[1] 唐亚平[1] 刘马林[1] CHEN Meng;CHEN Zhao;LIU Rongzheng;LIU Bing;SHAO Youlin;TANG Yaping;LIU Malin(Institute of Nuclear and New Energy Technology,Tsinghua University,Beijing 100084,China)

机构地区：[1]清华大学核能与新能源技术研究院,北京100084

出　　处：《清华大学学报（自然科学版）》2022年第10期1645-1659,共15页Journal of Tsinghua University(Science and Technology)

基　　金：国家科技重大专项(2017ZX06901025)。

摘　　要：利用流化床-化学气相沉积(fluidized bed-chemical vapor deposition,FB-CVD)技术制备包覆燃料颗粒是高温气冷堆燃料元件生产过程中的关键工艺之一,该文首先分析了FB-CVD颗粒包覆过程的特点,并综合流化床中的速度场、温度场、浓度场及CVD模型建立了CFD-DEM-CVD多物理场多尺度耦合模型用于颗粒包覆过程的研究。然后从多个方面优化包覆模型,分别提出了CRF模型用于模拟物质的分解和沉积过程,PBM模型用于求解沉积组分的尺径分布及IBP模型用于求解包覆颗粒密度的改变。将该文提出的包覆模型用于实际的案例计算发现,模拟结果和实验结果吻合较好,验证了模型的可靠性和准确性。该文建立的颗粒包覆模型可以作为一种基础理论模型拓展颗粒学学术研究范畴,还可用于颗粒包覆过程的研究,为实际的工业生产提供理论指导。The preparation of coated fuel particles using fluidized bed-chemical vapor deposition(FB-CVD)is one of the key processes in the production of fuel elements for high-temperature gas-cooled reactors.The characteristics of the particle coating process were predicted using a multi-physics,multi-scale,coupled CFD-DEM-CVD model to predict the velocity,temperature,and concentration fields for the CVD method in fluidized beds.Then,the coating method was modeled using a chemical reaction flow model to simulate the decomposition and deposition of the chemical substances with the population balance model used to solve for the size distribution of the deposited components and the inner bonding particle model used to predict the changes in the coating particle density.This coating model was used to simulate various cases with the simulation results in good agreement with experimental data.This coating model can be used to study the particle coating process and optimize coating processes for industrial production.

关 键 词：颗粒包覆 流化床-化学气相沉积(FB-CVD) 数值模拟 CFD-DEM 多尺度耦合 

分 类 号：TQ021.1[化学工程]