离心泵瞬态空化流动压力脉动及空泡形态

发布时间：2018-02-04 10:10

本文关键词： 离心泵瞬态空化流动压力脉动空泡形态　出处：《中国农村水利水电》2017年09期 　论文类型：期刊论文

【摘要】：基于RNG k-ε湍流模型和改进的质量输运空化模型,数值模拟了离心泵内瞬态空化流动。数值计算得到的离心泵扬程随有效空化余量的变化与试验结果吻合较好,验证了数值模型和计算方法的准确性。在离心泵叶轮内叶片吸力面、流道中间及叶片压力面布置监测点,分析叶轮内压力脉动特性及瞬态空泡形态。结果表明:叶轮内压力脉动主频为叶轮转频及其谐频;在叶片吸力面,叶轮内压力脉动最大幅值在距进口4/5处最大,流道中间及叶片压力面,压力脉动最大幅值由进口至出口渐渐增大,在出口处最大。叶轮流道内空泡随时间经历发展、断裂、溃灭的周期性变化过程;空泡连续的大尺度再生和溃灭造成压力脉动幅值增大,附着型空泡导致压力脉动幅值减小。
[Abstract]:Based on RNG k- 蔚 turbulence model and improved mass transport cavitation model. The transient cavitation flow in a centrifugal pump is simulated numerically, and the variation of the pump head with the effective cavitation allowance is in good agreement with the experimental results. The accuracy of the numerical model and the calculation method is verified. Monitoring points are arranged on the suction surface of the blade in the impeller of the centrifugal pump the middle of the flow channel and the pressure surface of the blade. The characteristics of pressure pulsation and the transient cavitation morphology in impeller are analyzed. The results show that the main frequency of pressure pulsation in impeller is turbomachinery frequency and its harmonic frequency. In the blade suction surface, the maximum value of pressure pulsation in the impeller is 4/5 from the inlet, and in the middle of the passage and the pressure surface of the blade, the maximum value of the pressure pulsation increases gradually from the inlet to the outlet. At the outlet, the cavitation in the impeller passage changes periodically with the development, fracture and collapse of the impeller flow channel. The continuous large-scale regeneration and collapse of cavitation increase the amplitude of pressure pulsation and decrease the amplitude of pressure pulsation caused by attached cavitation.
【作者单位】：内蒙古化工职业学院;包头轻工职业技术学院;内蒙古工业大学;
【基金】：国家自然科学基金项目(51579006);国家自然科学基金项目(51679122) 北京市自然科学基金项目(3164045) 内蒙古自治区高等学校科学研究项目(NJZY17450)
【分类号】：TH311
【正文快照】： 3.内蒙古工业大学,呼和浩特010051)空化的非定常特性对水力机械运行效率、振动和噪声影响重大[1-3]。Kubota等[4]观测了绕水翼云状空化的结构,结果显示空化初生和发展过程中含有许多微小的空泡集中涡,并指出空穴尾部脱落是近壁反向射流的结果。Pham等[5]对翼型片状空化进行了

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