农业机械学报2017，Vol.48Issue(2)：117-125,9.DOI:10.6041/j.issn.1000-1298.2017.02.016
斜流泵小流量工况压力脉动数值模拟与实验
Numerical Simulation and Experiment of Pressure Fluctuation in Mixed-flow Pumps under Low Flow Conditions
摘要
Abstract
The pressure fluctuation experiment was conducted and the entire flow field of mixed-flow pump was simulated by large eddy simulation (LES) with standard Smagorinsky subgrid scale model to investigate pressure fluctuations and mixed-flow pump inner flow under low flow conditions.The experimental results indicated that the multiples of pressure fluctuation at the impeller inlet was the highest and it was increased when the flow rate was decreased.the main pressure fluctuation frequencies at the impeller inlet,impeller ouflet and vanes inlet were blades passing frequency under different conditions,however,the main pressure fluctuation frequencies at the vanes outlet was changed under different conditions.The large eddy simulation results indicated that the flow conditions at impeller inlet was better and axial velocity was changed small under 0.8Qopt (Qopt,operating condition).Under 0.4Qopt,however,the flow conditions at impeller inlet became complicated,therefore,the axial velocity was changed significantly.The angle of attack of the fluid on the blades was increased and affected by tip leakage flow.The flow separation was generated at the leading edge of suction surface at t* =0.041 6,when the impeller was rotated from t* =0.041 6 to t* =0.124 9,the flow separation was intensified and the swirling strength of the separation vortex was gradually increased,so the static pressure of the leading edge of suction surface was decreased,the adverse pressure gradient was increased which promoted the generation of backflow.When the backflow reached the leading edge,the static pressure of leading edge was gradually restored,therefore the flow separation was an important reason that making the multiples of pressure fluctuation increased.关键词
斜流泵/小流量工况/压力脉动/数值模拟Key words
mixed-flow pump/low flow conditions/pressure pulsation/numerical simulation分类
机械制造引用本文复制引用
张德胜,刘俊龙,耿琳琳,石磊,张俊杰..斜流泵小流量工况压力脉动数值模拟与实验[J].农业机械学报,2017,48(2):117-125,9.基金项目
国家自然科学基金面上项目(51479083)、江苏省产学研前瞻性联合研究项目(BY2015064-08)、江苏省重点研发计划项目(BE2015001-3)和江苏省优势建设学科项目 （51479083）
