两相流弯管内流场与磨损研究

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为了研究弯管内的二次流、分离流、颗粒分布及预测磨损的位置及变化,本文通过欧拉-拉格朗日法利用CFD-DEM耦合对不同曲率(30、60、90、120°)弯管中的内流场和管壁磨损进行了模拟.结果发现弯管中主要有管道涡和脱落涡两种,涡核开始于弯曲处且向出口阶段延申,随着角度的增大,涡等值面减小;通过分析得出在颗粒进出平衡时,90°弯管内的颗粒数量最多、30°弯管时的颗粒数量最少;对比发现磨损最严重的区域为弯曲管壁,60°弯管时的总磨损量为最大,并利用matlab拟合了四个角度管道的磨损变化公式.本文揭示了不同角度弯管内的流场、磨损等变化,对管道运输、离心泵等机械进出口管道等应用与改进具有特殊的意义.
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