二维双区球流运动唯象方法的参数分析

Parameter Analysis for Pebble Dynamics of Two-Dimensional TwoRegion Pebble-Bed Reactor using Phenomenological Method

为了研究摩擦系数和底部倾角对双区球流的运动影响,参照二维堆芯球流运动实验台架,采用离散单元法对双区球流运动进行数值模拟,并从唯象的角度对不同摩擦系数和底部倾角下双区的分布、中心区/交混区及滞留区等问题进行分析。结果表明:随着摩擦系数增大,球流动更加均匀,滞留区在一定范围内随之增大,交混区域有所减小。底部倾角越大,流动越均匀,滞留区和缓慢流动的区域越小。

In order to investigate the parameter effects on the pebble dynamics in the high-temperature reactor core where the fuel pebbles and graphite pebbles form two regions, based on the two-dimensional pebble-dynamics experiments, the discrete element method（DEM） was used to simulate the pebble-dynamics and phenomenological method was used to analyze the two-region arrangement, the size and shape of the central pebble column, the dispersion in the mixing region and the stagnant regions at different friction coefficient and different cone angle. The results show that with the increasing of the friction coefficient, the ball flow tends to more uniform, the stagnant zone increases and the mixing zone decreases. While the cone angle increases, the flow seems more even, the stagnant zone and the slow zone decrease.