不同前缘后掠角的双叶片污水泵性能模拟与试验  

Performance simulation and experiment of different leading edge back-swept angle on double blade sewage pump

作　　者：陈刻强 施卫东[1] 张德胜[1] 郎涛[1] 程成[1] 

机构地区：[1]江苏大学流体机械工程技术研究中心,镇江212013

出　　处：《农业工程学报》2014年第19期48-54,F0003,共8页Transactions of the Chinese Society of Agricultural Engineering

基　　金：江苏高校优势学科建设工程项目;国家科技支撑计划项目(2011BAF14B01);江苏省"333工程"科研项目;江苏省产学研联合创新资金前瞻性研究项目(BY2013065-03)

摘　　要：为了研究前缘后掠角对前伸式双叶片污水泵水力性能的影响规律并大幅提高泵效率,基于某一款典型的前伸式双叶片污水泵(WQ800-40-132),设计了4个不同的叶轮模型,其前缘后掠角分别为60°、100°、140°、180°。利用ICEM CFD 14.5软件对计算模型进行结构化网格划分,采用Ansys CFX 14.5软件对网格模型进行基于标准k-ε湍流模型和可缩放壁面函数的全流场数值模拟,分别从泵的外特性及内流场分析了前缘后掠角对泵性能的影响规律,结果发现:随着前缘后掠角的增加,扬程流量曲线趋于平坦,轴功率则不断增大,最高效率点向大流量工况方向偏移;在大流量工况下(1.2Qn,Qn为设计流量),前缘后掠角的增大会导致进口前缘外周边的叶片工作面处出现回流,并在前缘上方形成旋涡,造成较大的水力损失。通过对数值模拟与样机试验的结果对比,发现模拟值与试验值有较小的差别,但整体趋势基本相同。该文的研究结果对双叶片污水泵的优化设计具有较好的参考价值。The back-swept double blade sewage pump studied in the paper belongs to the new high efficiency non-clogging pump. It has a self-cleaning ability, and can effectively solve the problem of fiber winding and congestion. This research study designed to probe the effect of the leading edge back-swept angle on a forward-extended double blade sewage pump. By changing the leading edge shape to get different degrees of back-swept blade, four models of impellers with different back-swept angles of 60°, 100°, 140°, and 180° were created by BladeGen. According to the structure of the pump, we divided the fluid domain into six parts, namely entrance region, impeller, volute, front chamber, back chamber, and outlet section, which were modeled by Unigraphics NX. ICEM CFD software was used for dividing the structured mesh of each part, and the numerical simulation of the whole flow field was performed based on a standard k-ε turbulence model and scalable wall function. The total pressure inlet condition and mass flow rate outlet condition were adopted in the computational domains. The impeller was defined as rotating domain with a speed of 1 450 r/min. Both front and back of the pump cover plate walls were set to the rotating walls with the speed of 1 450 r/min. Other domains and walls were defined as static fields or walls. The discrete control equations were based on the finite element of finite volume method. The convective term was a high resolution format and convergence precision was set to 10-4. At the same time, the trend of the pump head, efficiency, and power curves were leveling out to ensure the credibility of the calculation results. To further ensure the accuracy of the simulation results, a sewage pump of 100° back-swept angle was produced and tested. Comparison between the numerical simulation and experimental results was presented to prove the accuracy of the numerical simulation. Comparing performance curves concluded from the simulation, we found that the best efficiency point of pump shifts to the high

关 键 词：泵 数值方法 叶轮 前缘后掠角 双叶片污水泵 水力设计 数值计算 

分 类 号：TH311[机械工程—机械制造及自动化]