铅铋合金夹杂颗粒对含缺陷弯管侵蚀的数值模拟

Numerical simulation of erosion in defective L-bends caused by particles in lead-bismuth alloy

采用计算流体动力学与离散相模型耦合的方法,计算不同工况条件下存在缺陷管道的侵蚀速率。对比不同工况下的侵蚀速率和侵蚀关键区域,揭示了缺陷对侵蚀的影响模式。研究结果表明:(1)随着铅铋共晶流速的增加,含缺陷管道和完整管道的侵蚀区域均显著扩大。含缺陷管道的最大侵蚀速率降低,完整管道的侵蚀速率略有上升。(2)颗粒尺寸的增大会导致含缺陷管道的侵蚀区域从缺陷位置转移至入口直管段;对于完整管道,侵蚀则集中在弯管入口附近,两种管道的侵蚀区域均明显扩大。(3)缺陷的存在增加了凹坑位置的湍流强度,弯管的侵蚀位置集中于凹坑位置,并随着凹坑尺寸的增大,凹坑位置的最大侵蚀速率也显著上升。

The method of coupling computational fluid dynamics and discrete phase model was used to calculate the erosion rate of defective pipes under different working conditions.The erosion rate and erosion key areas under different working conditions are compared,and the influence mode of defects on erosion is revealed.The results show that:(1)With the increase of lead-bismuth eutectic flow velocity,the erosion area of both defective and intact pipelines expands significantly.However,the maximum erosion rate of defective pipes decreased,and the erosion rate of intact pipes increased slightly.(2)The increase in particle size will cause the erosion area of the defective pipe to shift from the defective location to the inlet straight pipe section;for intact pipelines,the erosion is concentrated near the entrance of the elbow,and the erosion area of both pipelines is significantly expanded(.3)The existence of defects increases the turbulence intensity at the pit location,and the erosion position of the elbow is concentrated in the pit position,and the maximum erosion rate of the pit position increases significantly with the increase of the pit size.