摘要
为研究离心泵作透平(pump as turbine,PAT)启动过程中的瞬态特性,根据转动方程编写UDF程序,基于Fluent软件滑移网格的转速控制方法对PAT启动过程进行模拟计算,并与试验结果进行对比验证。结果表明,启动初始时刻叶轮内形成了强烈的叶道涡,随着转速的增加,叶道涡的强度逐渐减小,压力呈梯度分布。启动初始时刻叶片载荷振荡分布,最大振幅出现在叶片中间位置,远高于稳态工况下的叶片载荷;径向力和轴向力都随着转速的增加急剧增大后振荡下降,当转速趋于稳定后,径向力和轴向力呈周期性振荡,轴向力脉动的幅值大于径向力的,每个振荡周期的脉动次数与叶片数一致。启动过程中转子做加速度逐渐减小的加速转动,来流压力越大,达到设计转速的时间越短,完成启动后的稳定转速越高;转动惯量越小,完成启动越快。
Here,to study transient characteristics of centrifugal pump as turbine(PAT)in its startup process,UDF programs were written according to rotating equation.The rotating speed control method based on Fluent sliding mesh was used to do numerical simulation of PAT startup process,and the simulated results were compared with test ones for verification.The results showed that strong blade channel vortices are formed inside impeller at startup initial instant,with increase in rotating speed,the intensity of blade channel vortex gradually decreases and pressure reveals gradient distribution;at startup initial instant,blade load reveals oscillatory distribution,its maximum amplitude appears at blade middle position,it is much higher than the blade load under steady state operating condition;both radial force and axial one firstly increase sharply with increase in rotating speed and then drop oscillatorily;after rotating speed tends to be stable,radial force and axial one reveal periodic oscillation,axial force fluctuation amplitude is greater than that of radial force,and the fluctuation number in each oscillation period is consistent with blade number;rotor rotating speed is accelerated but its acceleration decreases gradually in startup process,the larger the pressure of incoming flow,the shorter the time to reach the designed rotating speed,and the higher the steady rotating speed after finishing startup;the smaller the moment of inertia,the faster the completion of startup.
作者
柴宝堆
杨军虎
王晓晖
姜丙孝
CHAI Baodui;YANG Junhu;WANG Xiaohui;JIANG Bingxiao(School of Energy and Power Engineering,Lanzhou University of Technology,Lanzhou 730050,China;School of Chemical and Biological Engineering,Lanzhou Jiaotong University,Lanzhou 730070,China)
出处
《振动与冲击》
EI
CSCD
北大核心
2021年第23期38-43,57,共7页
Journal of Vibration and Shock
基金
国家自然科学基金(51569013)
甘肃省高等学校产业支撑计划项目(2020C-20)。
关键词
泵作透平(PAT)
启动过程
转速
瞬态特性
pump as turbine(PAT)
startup process
rotating speed
transient characteristics
作者简介
第一作者:柴宝堆,男,博士生,讲师,1987年生;通信作者:杨军虎,男,教授,博士生导师,1962年生。
