开缝叶片低比转数离心泵空化性能的数值模拟

发布时间：2018-06-24 00:06

本文选题：低比转数离心泵 + 开缝　；参考：《排灌机械工程学报》2016年03期

【摘要】：为了进一步提高低比转数离心泵的空化性能,对离心泵叶轮叶片进口附近的开缝进行研究.考虑开缝的3个参数,设计6组水力模型探究开缝对低比转数离心泵性能的影响.针对离心泵运行过程中产生空化的流动特点,基于Rayleigh-Plesset方程来描述空泡成长和溃灭过程的空泡动力学模型,采用RNG k-ε模型对在相同工况下的离心泵中两相流动进行数值模拟与分析.模拟结果表明:在叶片进口处开缝可以提高泵空化性能,其中第二组模型的空化性能提升比较明显,空化余量由4.447 m下降到3.910 m,降低了12.1%,水力效率由71.56%上升至76.46%;在相同工况下,开缝叶轮流道内的能量分布更加均匀,而扬程在额定流量下只有很小的变化.该模拟结果对研究低比转数离心泵内部流动特性及性能的提升具有一定的参考价值.
[Abstract]:In order to further improve the cavitation performance of low specific rotation centrifugal pump, the slit near the inlet of impeller blade of centrifugal pump was studied. Considering three parameters of slit, six groups of hydraulic models were designed to explore the effect of slit on the performance of low specific rotation centrifugal pump. Based on Rayleigh-Plesset equation, the cavitation dynamics model of cavitation growth and collapse process is described based on Rayleigh-Plesset equation. The RNG k- 蔚 model is used to simulate and analyze the two-phase flow in a centrifugal pump under the same working conditions. The simulation results show that the cavitation performance of the pump can be improved by opening at the inlet of the blade, and the cavitation performance of the second group of models is obviously improved. The cavitation allowance is decreased from 4.447 m to 3.910 m, and the hydraulic efficiency is increased from 71.56% to 76.46g, and the hydraulic efficiency is increased from 71.56% to 76.46g under the same working conditions. The energy distribution in the flow channel of the slit impeller is more uniform, but the lift varies only slightly at rated flow rate. The simulation results have some reference value for the study of flow characteristics and performance improvement of low specific speed centrifugal pump.
【作者单位】：江苏大学国家水泵及系统工程技术研究中心;
【基金】：江苏高校优势学科建设工程项目
【分类号】：TH311

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