沙集泵站改造叶轮选型及流道改形研究  

Study on impeller selection and channel modification of Shaji pump station

作　　者：赵文军[1] 刘木秀 王铁力 仇宝云 黄先北 ZHAO Wenjun;LIU Muxiu;WANG Tieli;QIU Baoyun;HUANG Xianbei(Jiangsu Luoyun Water Conservancy Project Management Office,Suqian 223800,China;Yangzhou University,Yangzhou 225127,China;Jiangsu Surveying and Design Institute of Water Resources Co.,Ltd.,Yangzhou 225127,China)

机构地区：[1]江苏省骆运水利工程管理处,江苏宿迁223800 [2]扬州大学,江苏扬州225127 [3]江苏省水利勘测设计研究院有限公司,江苏扬州225127

出　　处：《流体机械》2024年第7期88-97,共10页Fluid Machinery

基　　金：国家自然科学基金项目(52179091);江苏省水利科技项目(2021023、2022016)。

摘　　要：针对沙集泵站空化汽蚀较为严重,在工程加固改造时主体结构不变,无法通过降低站房底板增加叶轮淹没深度,从而提高空化性能的实际问题,采用计算流体动力学CFD方法,考虑泵站进口不同水位,对水泵装置全流道内部流动进行数值分析,研究水泵空化和能量特性。小幅降低叶轮中心高程,不仅未能减小空化范围,反而降低了泵装置效率,不宜采用。通过优选水泵水力模型、降速、增径并适当修整流道等方法,在保证泵装置能量性能的前提下,提高水泵空化性能。结果表明,采用方案一:叶轮直径增至1.68 m,转速降至250 r/min,基本消除了叶片进水边附近的附着空化,同时能够满足泵站特征水位组合下的流量和效率。成果也可用于类似泵站的设计和机组的选型。In view of the actual problem that the cavitation of Shaji Pump Station is relatively serious,and cavitation performance cannot be improved by lowering the bottom plate of the station building to increase the submergence depth of the impeller when the main structure remains unchanged during the project reinforcement and reconstruction,the computational fluid dynamics(CFD)method was adopted to conduct numerical analysis of the internal flow in the full flow passage of the pump unit by taking into account the different water levels at the inlet of the pump station to study the cavitation and energy characteristics of the pump.The small reduction of impeller center elevation not only fails to reduce the cavitation range,but also reduces the efficiency of the pump unit,which is not suitable for use.The cavitation performance of the pump can be improved by optimizing the hydraulic model,reducing the speed,increasing the diameter,and properly modifying the flow passage on the premise of ensuring the energy performance of the pump unit.The results show that the adoption of the first scheme:the impeller diameter is increased to 1.68 m and the rotating speed is reduced to 250 r/min,basically eliminates the attached cavitation near the inlet edge of the blade,and can meet the flow and efficiency under the combination of characteristic water levels of the pump station.The results can be used for the design of similar pump stations and the selection of units.

关 键 词：大型立式导叶式混流泵站 更新改造 空化性能 叶轮选型 CFD预测 

分 类 号：TH3[机械工程—机械制造及自动化]