非线性空泡模型在轴流泵空化模拟中的评估分析  

Assessment of a Non-linear Cavitation Model for the Computations of Cavitating Flow in an Axial Flow Pump

作　　者：洪锋 张天宇 苏华山 袁建平[3] 张帆 Hong Feng;Zhang Tianyu;Su Huashan;Yuan Jianping;Zhang Fan(College of Mechanical and Power Engineering,China Three Gorges University,Yichang 443002,China;Hubei Key Laboratory of Hydroelectric Machinery Design&Maintenance,China Three Gorges University,Yichang 443002,China;China National Research Center of Pumps,Jiangsu University,Zhenjiang 212013,China)

机构地区：[1]三峡大学机械与动力学院,湖北宜昌443002 [2]三峡大学水电机械设备设计与维护湖北省重点实验室,湖北宜昌443002 [3]江苏大学国家水泵及系统工程技术研究中心,江苏镇江212013

出　　处：《流体机械》2020年第6期55-61,共7页Fluid Machinery

基　　金：国家自然科学基金项目(51809121);湖北省自然科学基金项目(2019CFB193);湖北省水电机械设备设计与维护重点实验室(三峡大学)开放基金项目(2018KJX04、2018KJX06)。

摘　　要：为了提高传统空化模型预测轴流泵空化特性的能力,提出了一种基于非线性Rayleigh-Plesset方程的空泡动力学模型,联立两相-3种组分的均相流假设,建立了一种非线性空化模型。分别采用非线性模型及传统的Schnerr-Sauer模型对比转速ns=692的轴流泵叶轮内空化流动进行数值计算。研究发现:非线性模型预测的轴流泵空化性能曲线与实验测量值吻合更好,叶顶间隙内附着型空化长度随着空化数的降低呈现先缓慢增长后迅速增长的规律;当轴流泵叶片吸力面发生严重空化时,空化区域的后部靠近轮毂的位置空泡体积分数发生了急剧变化,该处最容易发生空蚀破坏。In order to enhance the capability of predicting cavitating flows for traditional cavitation models,an alternative nonlinear cavitation model developed based on an improved Rayleigh-Plesset equation and the homogeneous flow assumption was proposed.The turbulent cavitating flows at various flow rates in an axial flow pump with a specific speed ns=692 were computed and compared by the proposed and the Schnerr-Sauer models.The results show that the cavitation performance predicted by the proposed model is in better agreement with the measured value in the experiments than that by the Schnerr-Sauer model.The length of the attached sheet cavity inside the tip leakage clearance increases slowly at the beginning,and then rapidly increases with the decrease of cavitation number.The vapor volume fraction of the cavity which is located in the rear part under severe sheet/cloud cavitation formed at the connection area of the suction surface and hub changes quickly,indicating the cavitation erosion is always generated at the connection area.

关 键 词：轴流泵 非线性空化模型 空化 数值计算 

分 类 号：TH311[机械工程—机械制造及自动化]