TRISO颗粒缓冲层包覆喷动床气固流动特性  

Hydrodynamics of spouted bed in TRISO particle buffer layer coating process

作　　者：麦锡源 张锋[1] 林俊[1] 王鹏[1] 朱智勇[1] 

机构地区：[1]中国科学院上海应用物理研究所嘉定园区,上海201800 [2]中国科学院大学,北京100049

出　　处：《核技术》2015年第4期48-53,共6页Nuclear Techniques

基　　金：中国科学院战略性先导科技专项(No.XDA02030200)资助

摘　　要：TRISO(Tristructural isotropic)颗粒的包覆层是通过喷动床化学气相沉积法制备的。本研究基于拟流体模型,应用Fluent软件对核燃料缓冲层包覆过程中颗粒性质随时间的变化进行了计算分析,考察了颗粒性质的变化对喷动床气固流动特性的影响。结果表明,随着缓冲层包覆过程中颗粒的直径增大和密度减小,喷泉高度减小,喷射区中的颗粒数量减小,喷射区中的气体升温速率降低,由此影响包覆效率。Background： The coating of TRISO （Tristructural isotropic） type fuel particle is prepared by chemical vapor deposition in spouted bed. Gas and solid flow behaviors are considerably influenced by particle properties during coating process. Purpose： This study aims to investigate the influence of particle properties on gas and solid flow behavior in spouted bed. Methods： Based on the two-fluid model, the Fluent software was applied to conduct simulation of the property change of particle during the spouting process with emphasis on particle spatial distribution, volume fraction and gas temperature on centerline of spout zone. Experiments were set up to compare and verify simulated results. Results： It is found that fountain height and particle quantity in spout zone decreased with coating process. Gas heating rate in spout zone decreased with the increase of particle diameter and the decrease of particle volume fraction. Conclusions： Increase in particle diameter has a considerable effect on hydrodynamics of spouted bed during coating process. The inlet gas flow rate is suggested to adjust to maintain the steady gas-solid hydrodynamic state at the later stage of coating process. In the meanwhile, temperature of furnace wall and inlet gas should be appropriately increased to maintain a proper pyrolysis rate.

关 键 词：TRISO颗粒 核燃料 喷动床 

分 类 号：TQ051.15[化学工程]