水泵水轮机泵工况FLI驼峰与迟滞效应流动机理的研究

项目名称： 水泵水轮机泵工况FLI驼峰与迟滞效应流动机理的研究

项目编号： No.51506126

项目类型： 青年科学基金项目

立项/批准年度： 2016

项目学科： 能源与动力工程

项目作者： 阳君

作者单位： 上海理工大学

项目金额： 21万元

中文摘要： 水泵水轮机泵工况下性能曲线在近设计点出现的驼峰及伴随的迟滞效应(又称为FLI)是制约抽水蓄能电站安全稳定运行的瓶颈之一。目前，学术界对该驼峰及其迟滞效应的成因与机理尚未形成统一解释。本项目将基于实验和数值模拟，采用流场可视化特征量频域分析法，研究引起该现象的流动机理，进而提出控制策略。首先，通过高速摄影与数值模拟，获取迟滞效应初始时叶轮出口及导叶流道内流场的流态分布，探索各种流动现象如流动分离、回流、失速等与迟滞效应触发之间的关系。其次，建立水泵水轮机泵工况内部非定常流动诊断系统，通过分析导叶内动态压力信息获得发生该现象时导叶流道内的主要非定常流动的特征，包括特征频率、传播特征等。根据获得的非定流动特征频率，结合可视化流场特征量频域分析方法，获得非定常流动分布情况及发展规律对特性曲线FLI驼峰与其迟滞效应的影响，提出改善及抑制方法。

中文关键词： 水泵水轮机泵工况；满载荷失稳；非定常流动；流场可视化；频域分析

英文摘要： Full load instability in the performance curve of pump turbine on pump mode, including hump and hysteresis, is one of the key issues which affect the safe and stable operation of pumped storage station. So far, there is no consensus theory to explain the causes of this instability and hysteresis. In this project, dynamic pressure measurement, high-speed flow visualization and numerical simulation are adopted to study the unsteady flow in this instability region. Firstly, analyses of the results of high-speed flow visualization and simulation, which are obtained at initial state of the hysteresis, are conducted to explore the relationship between the unsteady flows and the trigger condition of hysteresis. Secondly, an analysis system is established to diagnose the dynamic characteristics of the unsteady flow inner pump turbine on pump mode. The dynamic pressure signals from diffuser are analyzed by this system to get the characteristics of the main unsteady flows in this instability region. Thirdly, based on the characteristic frequencies of the unsteady flows, frequency analysis of the flow field visualization both by high-speed flow visualization and simulation are carried out to obtain the distribution of these unsteady flows. On the basis of the above analysis, some meaningful results, which can be provided to contribute the understanding on origins and development of the unsteady flow inner pump turbine in this instability region, could guide the design and optimization of the pump turbine.

英文关键词： Pump turbine on pump mode ;Full load instability;Unsteady flow;Flow visualization;Frequency analysis