雷诺数与间隙尺度对多级泵动静腔不稳定流动的影响机理研究

The stability and reliability of multistage pump during start and stop process have become one of the urgent problems needed to solve in major strategic project area. Unsteady rotor-stator cavity flow belongs to the basic research to solve this problem. This project choose a typical multistage pump as research model to study the influence mechanism of Reynolds number and gaps scale on unsteady rotor-stator cavity flow. Study methods including Detached Eddy Simulation associating with low Reynolds number correction and curvature correction, time-resolved PIV and pressure measurement. Average flow field and coherent flow field will be obtained by the orthogonal decomposition, vortex core trajectory and spatial distribution will be analyzed employing parallel vector method. The primary and temporal evolution process of instability flow will be studied under different rotating speed and different flow rates, such as Taylor vortex, spiral vortex and wavy vortex. The influence mechanism of gaps scale on secondary loop flow inside the rotating core, top edge backflow and seal gap leakage flow will be clarified. By studying the difference and regular pattern, to establish the stage coupling model of core rotating factor. This project aims to reveal the effects of Reynolds number and gaps scale on the unsteady flow and axial force transient characteristics, propose the effective method to control or balance the axial force, and provide a theoretical and scientific basis to improve the operational reliability of high-pressure multistage pump.

多级泵启动、停机等变速过程中的稳定性和可靠性问题已成为国家重大战略工程急需解决的难题之一，研究动静腔不稳定流动属于解决该问题的基础研究。本项目以典型多级泵模型为研究对象，采用考虑低雷诺数修正和曲率修正的分离涡模拟、时间分辨TR-PIV、压力测量等实验手段，研究雷诺数和间隙尺度对动静腔不稳定流动的影响机理；基于本征正交分解获取动静腔体流的平均流场和拟序流场，采用平行矢量法分析涡核运动轨迹和空间分布特征，研究不同转速、不同流量下泰勒涡、螺旋涡和波状涡等失稳流态的初生和时空演化过程，阐明间隙参数对旋转核二次环流、盖板顶缘回流和密封间隙泄漏流等不稳定流动的影响机制；分析不稳定流动的级间差异和变化规律，建立多级泵核心旋转系数级间耦合模型。本项目旨在阐明雷诺数和间隙尺度对多级泵动静腔不稳定流动和轴向力瞬态特性的影响，提出有效控制或平衡轴向力的方法，为改善高压多级泵的运行可靠性提供理论基础和科学依据。

多级泵是农业灌溉、地下水抽取、高压供水系统等的核心设备，其启动、停机等变速过程中的稳定性和可靠性问题已成为国家重大战略工程急需解决的难题之一，研究动静腔不稳定流动属于解决该问题的基础研究。本项目以典型多级泵模型为研究对象，采用考虑低雷诺数修正和曲率修正的分离涡模拟、PIV、压力测量等实验手段，研究雷诺数和间隙尺度对动静腔不稳定流动的影响机理；研究不同转速、不同流量下泰勒涡、螺旋涡和波状涡等失稳流态的初生和时空演化过程，分析不稳定流动的级间差异和变化规律。本项目旨在阐明雷诺数和间隙尺度对多级泵动静腔不稳定流动和轴向力瞬态特性的影响，提出有效控制或平衡轴向力和压力脉动的方法，为改善高压多级泵的运行可靠性提供理论基础和科学依据。在项目研究期间，在国内外学术期刊发表论文18篇，其中SCI检索论文13篇，EI检索论文2篇；获授权发明专利4件，授权实用新型专利1件；培养博士研究生1名，硕士研究生3名。先后荣获2018年教育部优秀科技成果二等奖、2019年江苏省科技进步二等奖。