叶轮外径对离心泵内流影响的CFD分析  

CFD analysis on effects of impeller outlet diameter on flow field in centrifugal pump

作　　者：谈明高[1] 刘厚林[1] 王勇[1] 王凯[1] 董亮[1] 

机构地区：[1]江苏大学流体机械工程技术研究中心,江苏镇江212013

出　　处：《排灌机械》2009年第5期314-318,共5页Drainage and Irrigation Machinery

基　　金：国家863计划项目(2006AA05Z250);江苏大学高级人才科研启动基金资助项目(09JDG026)

摘　　要：采用FLUENT,在双参考坐标系下,利用有限体积法对雷诺时均Navier-Stokes方程进行数值离散,选用标准k-ε湍流模型,SIMPLEC方法求解,对6台离心泵在不同叶轮外径下的内部流场进行了叶轮和蜗壳的耦合数值模拟.根据数值模拟结果对6台离心泵的能量性能进行了预测,并分析了叶轮外径变化对泵内部流场的影响.性能预测结果与切割定律计算结果的对比表明,随着叶轮外径的变化,泵扬程和轴功率的变化基本符合切割定律,但效率存在一定的波动.内部流场分析表明,叶轮外径变化对叶轮进口静压和总压分布的影响较小,对叶轮出口和蜗壳内静压及总压分布有着明显的影响;叶轮外径变化还对泵内尤其是蜗壳割舌附近的绝对速度分布有较大影响;当叶轮切割量大于4%后,蜗壳扩散段的流动分离现象就会逐渐消失.In the case of different impeller outlet diameters, the flow field in six centrifugal pumps was simulated by using FLUENT code. The standard k - ε turbulence model and SIMPLEC algorithm were chosen in FLUENT. The simulation was steady and moving reference frame was used to consider rotor - stator interaction. According to the simulation results,the head and shaft power of the model were predic- ted and the results were in accordance with cutting law, but the prediction efficiency was not constant. The flow analysis indicates that the change of impeller outlet diameter has obvious effects on static pres- sure and total pressure at impeller outlet and in volute. Also the change of impeller outlet diameter has important impacts on absolute velocity distribution, especially near the cutwater of the volute. When the cutting quantity is greater than 4%, the flow separation at the diffusion section of volute will disappear.

关 键 词：离心泵 叶轮 外径 蜗壳 流场 CFD 

分 类 号：TH311[机械工程—机械制造及自动化]