基于LES-PM的离心泵内部非定常空化流研究

项目名称： 基于LES-PM的离心泵内部非定常空化流研究

项目编号： No.51309120

项目类型： 青年科学基金项目

立项/批准年度： 2014

项目学科： 水利工程

项目作者： 王勇

作者单位： 江苏大学

项目金额： 25万元

中文摘要： 空化严重影响离心泵运行的稳定性和可靠性，制约着离心泵向高速化方向发展，是泵领域丞待解决的关键问题之一。本项目拟通过数值计算、实验测量和理论分析相结合的方法，深入研究离心泵内部非定常空化流演变过程和机理。 建立LES-PM计算方法，研究用于LES的预处理矩阵构造，以及空化流场中密度与压强的相互关系，确立伪可压缩系数的表达式；发展新的适用于离心泵内部空化流计算的输运方程类空化模型，研究特征长度和特征速度对空化流动的影响，研究相间质量传输率修正系数的优化方法；为了验证计算方法和模型，拟通过高速摄影和PIV-LIF测试技术，对离心泵内部的空化流场进行可视化实验研究，并同步测量不同空化状态下的振动和压力脉动特性，研究图像处理和空化特征信号分离方法。 本项目旨在建立一种能有效预测离心泵内部非定常空化流特性的计算方法，揭示离心泵内部空化流动机理，为提高离心泵效率和可靠性提供理论基础。

中文关键词： 离心泵；空化流；空化模型；湍流模型；实验测试

英文摘要： The stability and reliability of operating centrifugal pumps are often threatened by cavitation phenomenon, which restricts the development of pump turning to miniaturization. It is always one of the critical issure to be solved in pump industry. In this project, the evolution process and mechanism of the unsteady cavitation flow in centrifugal pumps will be lucubrated via numerical simulation, experiment test and theoretical analysis. Firstly,to establish LES-PM calculation method, the construction of the preconditioning matrix and the relationship between density and pressure in the cavitation flow are investigated. A so called pseudo-compressibility coefficient is formulated meantime. Secondly, in order to develop a novel cavitation model based on transport equation, which is suitable for computing the cavitation flow in the centrifugal pump, the influence of the cavity characteristic length and velocity on cavitating flow, and the optimization measure of interphase mass transport rate correction factor are researched. To verify the calculation method and computing model, the CCD camera and the PIV-LIF testing technique are employed to observe the cavitating flow in the centrifugal pump. In the meantime, the vibration and the pressure pulsation are tested with various cavitation conditions. Furthermore, it is

英文关键词： centrifugal pump；cavitating flow；cavitation model；turbulence model；experimental measurement