高温气冷堆换料过程的球流数值模拟与分析  

Numerical study and analysis of circulated granular flow in high-temperature gas-cooled reactors

作　　者：严安 孙喜明[1] 董玉杰[1] YAN An;SUN Ximing;DONG Yujie(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：《哈尔滨工程大学学报》2022年第8期1205-1211,共7页Journal of Harbin Engineering University

基　　金：国家科技重大专项(ZX069).

摘　　要：针对高温气冷堆球床堆芯换料过程中复杂的球流运动行为,本文完成了球流数值模拟与分析。应用离散单元方法对高温气冷堆球床堆芯进行建模,实现了极低换料速度下间歇性堆芯球流的准静态流动模拟。对比分析了不同的杨氏模量与球床高度下球流速度分布、流线分布和局部滞留等球床特性的差异,明确了杨氏模量的选取对于模拟结果可信程度的影响。结果表明:球体刚度、球床内球体数量的变化会显著影响球床底锥结构内的球流特性,球床的球流流态随球体数量的减少由整体流转变为漏斗流,球体杨氏模量不低于107 Pa,能较好地保证计算精度。Aiming at the complex granular flow behavior for typical refueling processes inside the pebble-bed core of high-temperature gas-cooled reactors,several numerical simulations and analyses of pebble flow are performed in this research.The discrete element method is applied to simulate such a refueling process in a high-temperature gas-cooled reactor,which realizes the simulation for the extremely slow,intermittent quasi-static pebble flow.Main features of the pebble flow,including velocity profile,streamline profile,and local pebble jamming are discussed under different Young′s modulus and bed heights.The effect of Young′s modulus on the reliability of simulation results is carefully examined and explored.Results reveal a nontrivial effect caused by rigidity and the number of pebbles,indicating that significant flow pattern variations exist within the cone structure with a decrease in the number of pebbles,which transforms from mass flow to funnel flow.The calculation accuracy can be ensured when the Young′s modulus of pebble is not less than approximately 107 Pa.

关 键 词：高温气冷堆 球床式反应堆 球流运动 准静态流动 离散单元法 杨氏模量 滞留效应 颗粒流流态 

分 类 号：TL351.1[核科学技术—核技术及应用]