摘要
建立了轴流泵-聚乙烯环管反应器的耦合模型,基于计算流体力学(CFD)模拟方法,研究了真实工况下进口流量与空化数对轴流泵流场特性的影响。结果表明,随着轴流泵进口流量减小,轴流泵临界空化数逐渐增大。当轴流泵内空化数小于临界空化数时,泵性能随着空化数的减小大幅度下降。为保证轴流泵能在高性能工况下运行,建议环管反应器内轴流泵空化数不低于25。同时发现,空化导致泵内液体流动轨迹发生偏移,引起流动分离现象,严重时甚至产生大量涡旋,使得轴流泵流场变得更加复杂与不稳定,造成大量能量损失,使得轴流泵性能变差。研究结果可为解决工业环管反应器内轴流泵运行不稳定的问题提供理论指导。
A coupled model of an axial flow pump and a polyethylene loop reactor was established,and the effects of inlet flow rate and cavitation number on the flow field characteristics of axial flow pump under real working conditions were studied based on a computational fluid dynamics(CFD)simulation method.The results indicate that as the inlet flow rate of the axial flow pump decreases,the critical cavitation number gradually increases;when the cavitation number in the axial flow pump is smaller than the critical cavitation number,the pump performance will be greatly reduced as the cavitation number decreases.In order to guarantee that the axial flow pump can run under high-performance working conditions,it is recommended that the cavitation number of the axial flow pump in loop reactor should not be smaller than 25.Moreover,it is found that the occurrence of cavitation will cause the deviation of the liquid flow trajectory in the pump,which will cause the flow separation phenomenon.In serious cases,it may even generate a large number of vortices,making the flow field of the axial flow pump more complicated and unstable,thus causing a large amount of energy loss and resulting in the poor performance of the axial flow pump.In conclusion,the research results can provide theoretical guidance for solving the problem of unstable running of the axial flow pump in industrial loop reactor.
作者
王晓飞
陆锦
孙婧元
WANG Xiaofei;LU Jin;SUN Jingyuan(Olefin Department of Tianjin Branch, SINOPEC, Tianjin 300270, China;College of Chemical and Biological Engineering, Zhejiang University, Hangzhou 310027, China)
出处
《石油学报（石油加工）》
EI
CAS
CSCD
北大核心
2022年第4期867-875,共9页
Acta Petrolei Sinica(Petroleum Processing Section)
基金
国家自然科学青年基金项目(21808198)资助。
关键词
环管反应器
轴流泵
空化
流场特性
计算流体力学(CFD)
loop reactor
axial flow pump
cavitation
flow field characteristic
computational fluid dynamics(CFD)
