旋流泵内部不稳定流动数值模拟  

Numerical simulation of internal unsteady flows in a vortex pump

作　　者：李洪彬[1,2] 蒋爽[1,2] 陈星宇 倪福生[1,2] 顾磊[1,2] 钟卫华 LI Hongbin;JIANG Shuang;CHEN Xingyu;NI Fusheng;GU Lei;ZHONG Weihua(College of Mechanical and Electrical Engineering,Hohai University,Changzhou 213022,China;Engineering Research Center of Dredging Technology,Ministry of Education,Hohai University,Changzhou 213022,China;Jiangsu Water Conservancy Machinery Co.,Ltd.,Yangzhou 225003,China)

机构地区：[1]河海大学机电工程学院,江苏常州213022 [2]河海大学疏浚技术教育部工程研究中心,江苏常州213022 [3]江苏省水利机械制造有限公司,江苏扬州225003

出　　处：《水利水电科技进展》2023年第3期28-33,48,共7页Advances in Science and Technology of Water Resources

基　　金：国家重点研发计划(2018YFC0407404);江苏省科技成果转化专项资金(BA2016143);河海大学大学生创新训练项目(202210294109Z)。

摘　　要：为深入了解旋流泵内部不稳定流动情况,基于RNG k-ε湍流模型,运用CFX软件对3种流量下的旋流泵进行非定常计算,分析了不同流体域的涡核、湍动能分布情况以及内部压力脉动特性。结果表明:随着流量的增加,进口管路涡核逐渐减少;无叶腔内圈首尾相连的圆形涡带直径和流速逐步变大,无叶腔外圈涡核逐步分散;无叶腔向扩散管过渡区域的涡核尺度显著增大,隔舌处的涡核尺度亦逐步增大。小流量和额定流量下,高亮湍动能集中于无叶腔内圈,内部压力脉动主频为叶频;大流量下,高亮湍动能集中于无叶腔向扩散管过渡区域,主频为轴频。叶轮中非涡核区多集中于叶片迎水面,随着流量的增加,涡核分布逐步分散,非核区域增多;高亮湍动能在小流量下分布在叶片入口,额定流量下分布在流道中部,大流量下分布在叶片出口;叶片流道内的压力脉动主频始终为轴频。In order to deeply understand the internal unsteady flows in vortex pumps,based on the RNG k-εturbulence model,numerical simulation of unsteady flows was carried out to analyze the vortex cores,turbulent kinetic energy distribution and internal pressure pulsation in different fluid domains of vortex pumps under three flow rates by CFX.The results show that the vortex cores of the inlet pipeline gradually decrease with increasing flow rates.The diameter and flow velocity of the circular vortex band connected end to end in the inner ring increases within the volute,and the vortex cores in the outer ring gradually disperse within the volute.The size of the vortex cores in the transition region of the diffuser tube and at the volute tongue increases significantly.Under low flow and rated flow conditions,the high-brightness turbulent kinetic energy is concentrated in the inner ring of the volute,and the main frequency of the internal pressure pulsation is the rotational frequency of the blade.Under large flow conditions,the high-brightness turbulent kinetic energy is concentrated in the transition area from the volute to the diffuser,and the main frequency is the rotational frequency of the axis.The non-vortex core area in the impeller is mostly concentrated in the upstream surface of the blade.With the increase of the flow rate,the vortex core distribution gradually disperses,and the non-core area increases.The high-brightness turbulent kinetic energy is distributed at the blade inlet under low flow,in the middle of flow channel under rated flow,and at the blade outlet under large flow.The main frequency of the pressure pulsation in the blade flow channel is always the rotational frequency of the axis.

关 键 词：旋流泵 涡核 湍动能 压力脉动 

分 类 号：TH311[机械工程—机械制造及自动化]