叶栅非稳态空化绕流诱导振动特性研究

项目名称： 叶栅非稳态空化绕流诱导振动特性研究

项目编号： No.51206063

项目类型： 青年科学基金项目

立项/批准年度： 2013

项目学科： 工程热物理与能源利用学科

项目作者： 李忠

作者单位： 江苏大学

项目金额： 25万元

中文摘要： 叶栅空化流激振动机理是发展低振动轴流泵主动控制技术的关键。本项目以直列791叶栅为研究对象，综合运用多种先进的测试技术及计算手段研究不同空化阶段叶栅三维绕流时空特征和振动特性。从输送介质的物性研究入手，构建空化本构关系，耦合分量涡模型和空化模型对空化非稳态两相流动结构进行模拟，结合空化流态宏观和微观特征的观测及流动参数的动态高频测量，刻画空化流动的三维形貌特性，分析汽液两相的动力特征，探索不同尺度流动结构演变的诱发因素及不同空化阶段间的转变机制。基于振动信号的高频测量和分析，探寻合适的空化流激振动双向流固耦合求解方法，探索空化流动特征、流体激励力、振动响应之间的关联关系，量化相关参数对叶栅绕流稳定性的影响水平，提出低振动叶栅优化方案。项目研究成果将从本质上加深对空化流动和流激振动机理的认识，丰富空化两相流动理论与研究方法，为轴流泵低振动设计方法的发展和运行稳定性的提高奠定理论和技术基础。

中文关键词： 空化流动；振动特性；叶栅；流固耦合；

英文摘要： The mechanism of cavitating flow around the cascade induced vibration is the key to develop active vibration control technology for axial-flow pump. Using advanced test technologies and simulation means, the characteristics of three-dimensional cavitating flow around a cascade of 791 hydrofoil and flow-induced vibration under different cavitation coefficient are mainly researched. Based on testing flow media physical property, the constitutive relation of cavitation is established. Coupling detached eddy simulation turbulence model and cavitation model, the unsteady cavitating flow around the cascade is simulated. The macro and micro characteristics of cavitating flow are captured by using high speed imaging and image processing technologies. The flow field paramenters and dynamic pressures at the hydrofoil surface are also measured. By analyzing the experimental results, the three-dimensional structure of cavitating flow and the dynamic characteristics of liquid-vapor phase behavior are obtained. The inducing factors of cavitating flow structure change and the transition mechanism of different cavitation stages are both revealed. With vibration signals testing and analysing, the appropriate fluid-solid coupling simulation method is set up. The relationship between cavitating flow characteristics, dynamic force

英文关键词： cavitaiton flow；vibration characteristics；cascade of hydrofoil；fluid-structure interaction；