摘要
为探究螺旋轴流式多相混输泵在非均匀来流条件下的气液两相分离机理,揭示高含气率工况下泵性能急剧下降至失效的流动机理,提升泵在复杂来流条件下的多相混输稳定性和效率,通过Fluent中的UDF(user-defined functions,UDF)功能对泵的进口边界条件进行非线性控制,选取线型和抛物型这2种非均匀来流边界条件,联合可视化试验,对不同来流情况下泵的外特性和流场结构进行对比分析.研究结果表明,不同非均匀来流均会使多相混输泵的性能下降,对流道内气液分离都有激化作用,并且线型来流的影响更严重.转速的增加会进一步激励泵的气液分离现象,在整个流域的轴向距离上,不同来流对气液分离激化从叶轮入口处开始,线型来流的气相从0.15 L处开始充斥流道,抛物型来流的气相在0.75 L分布最广.在叶片通道上,不同非均匀来流的湍动能在叶轮里分布是一致的,峰值相差1.00 m^(2)/s^(2),在导叶里线型来流的湍动能在空间上畸变严重.非均匀来流对多相混输泵气液分离现象有激化作用,影响泵的稳定运行,研究结论为多相混输泵工程实际应用和性能优化提供理论基础.
Aiming to elucidate the flow dynamics that lead to performance deterioration or failure at high gas volume fractions(GVF),gas-liquid two-phase separation mechanism in a helical axial multiphase mixed-transport pump under non-uniform inflow conditions was investigated to improve operational stability and efficiency in complex inflow scenarios.By implementing nonlinear control of the pump′s inlet boundary conditions via user-defined functions(UDF),two distinct non-uniform inflow profiles,i.e.,linear and parabolic were applied.Combined with flow visualization experiments,the hydraulic characteristics and internal flow structures of the pump were systematically analyzed under these conditions.The results demonstrate that non-uniform inflows universally degrade pump performance and exacerbate gas-liquid separation,with linear inflow exhibiting more severe effects.Increasing rotational speed further amplifies phase separation.Axially,gas-phase accumulation initiates at the impeller inlet:gas occupies the flow channel beyond 0.15 L for linear inflow,while parabolic inflow shows peak dispersion at 0.75 L.In the blade channel,the turbulent kinetic energy of different non-uniform incoming flows is uniformly distributed in the impeller,with a peak value difference of 1.00 m 2/s 2.However,the turbulent kinetic energy of the linear incoming flow in the guide vane is severely distorted in space.The study confirms that non-uniform inflow intensifies gas-liquid separation,destabilizing pump operation.These findings provide a theoretical foundation for optimizing multiphase mixed-transport pumps in engineering applications.
作者
权辉
王智胜
冯冰
王子源
李嘉仪
史广泰
QUAN Hui;WANG Zhisheng;FENG Bing;WANG Ziyuan;LI Jiayi;SHI Guangtai(College of Energy and Power Engineering,Lanzhou University of Technology,Lanzhou,Gansu 730050,China;Key Laboratory of Advanced Pumps Valves and Fluid Control System of the Ministry of Education,Lanzhou University of Technology,Lanzhou,Gansu 730050,China;School of Energy and Power Engineering,Xihua University,Chengdu,Sichuan 610039,China)
出处
《排灌机械工程学报》
北大核心
2025年第6期541-546,579,共7页
Journal of Drainage and Irrigation Machinery Engineering
基金
国家自然科学基金资助项目(51969014)
甘肃省杰出青年基金资助项目(20JR10RA204)
甘肃省陇原创新创业人才计划项目(2022年度人才发展专项)(2022LQGR51)
兰州理工大学红柳优秀青年人才支持计划项目。
关键词
多相混输泵
气液两相流
非均匀来流
可视化试验
气液分离激化
multiphase mixed-transport pump
gas-liquid two-phase flow
non-uniform inflow
visualization testing
gas-liquid separation
