摘要
为分析射流式自吸离心泵的半开式叶轮与导流器前盖之间的间隙大小对其性能的影响,采用数值模拟的方法得到了4种不同间隙下射流式自吸离心泵水力性能、径向力变化规律、自吸过程泵内部气液两相分布及流动情况,结果表明:间隙大小对射流式自吸离心泵水力性能影响明显,随着间隙增大,泵扬程和效率呈明显下降趋势,额定工况点间隙为0.5时的扬程和效率相对于间隙2mm时的扬程和效率分别下降14.43%、7.07%;叶轮与导流器上径向力也随间隙增大而减小;叶轮含气率、导流器两个不对称出口及泵体出口的气相质量流率随间隙增大而降低.兼顾考虑水力性能、自吸性能及加工装配工艺,最终确定叶轮与导流器前盖的间隙为0.5mm.样机试验结果表明:在额定工况点扬程34.21m,效率55.29%,当自吸高度为5m时,自吸时间45s,达到设计要求。
To analyze the performance effect which caused by the size of the clearance between the semi - open impeller and the front shroud of fluid director on flow-ejecting self-priming centrifugal pump, numerical simulation was carried out and the change rule of hydraulic properties, radial force change rule, gas-liquid two phase distribution and flow condition during the self-priming process of the pump at four different clearance＇ s size were obtained. The result show that the size of the clearance have signifi- cant effects on hydraulic properties, the head and efficiency of the pump significantly decrease along with the increasing of the clearance＇ s size. Under the rated condition, the head and efficiency drop by 14.43% ,7.07% separately when the clearance＇ s size change from 0.5mm to 2.0mm. The radial force on the impeller and fluid director also decrease along with the clearance＇ s size increasing. The air voids of the impeller and the gas phase flow rate of the asymmetrical exits of the diffuser on the fluid direc- tor decrease along with the clearance＇ s size increasing, too. Considering hydraulic properties, performance of self-priming, process- ing and assembly process,the clearance＇ s size was confirmed to be 0.5mm. The prototype test results show that the head is 34. 2Ira,efficiency is 55.29% under the rated condition. When the self-priming height is 5m, the self-priming time is 45s, meeting the design requirements.
出处
《流体机械》
CSCD
北大核心
2013年第3期5-9,共5页
Fluid Machinery
基金
国家"863"高技术研究发展计划资助项目(2011AA100506)
农业科技成果转化资金项目(2011GB2C100015)
关键词
半开式叶轮
导流器
射流式自吸离心泵
数值模拟
水力性能
自吸性能
semi-open impeller
fluid director
flow- ejecting self-priming centrifugal pump
numerical simulation
hydraulic properties
performance of self-priming
