排灌机械工程学报2017，Vol.35Issue(4)：303-308,318,7.DOI:10.3969/j.issn.1674-8530.15.0235
基于大涡模拟的混流泵不稳定流动数值研究
Analysis of instability flow on mixed-flow pump based on LES
摘要
Abstract
A flow-field analysis model of the mixed-flow pump was established in order to study the flow field and pressure pulsation characteristics under different operating conditions.The unsteady numerical simulation of the whole flow field under different operating conditions was carried out by Large eddy simulation(LES)based on the CFX software.The results show that the flow pattern was consistent at six channels except that a certain flow separation appeared on the suction surface near the guide vanes outlet at 1.00Qopt.When the rotating stall occurred,a lot of whirlpool developed near the suction surface of the guide vanes and the whirlpool scale increased first and then decreased from the inlet to the outlet at the guide vanes,moreover the vortex core was attached to the suction surface where the pressure fluctuation was the smallest.The pressure pulsationat different points was analyzed by FFT transform,which showed that the amplitude of the pressure pulsation increased gradually from the hub to the rim.The distributiom of the pressure pulsation frequency at the outlet was similar to that at the inlet except that the amplitude decreased a little and the dominant frequency shifted to the low-frequency direction.Additionally,the pressure pulsation under different operating conditions was also analyzed.The changing regularity of three operating conditions was consistent.However,the frequency range is larger and the frequency components are more complex at 0.55Qopt condition than at 0.75Qopt and 1.00Qopt condition.At 0.75 Qopt the low-frequency width is significantly reduced and the frequency of low-frequency pulsation was concentrated around 1N,while at 1.00Qopt,the frequency was not obvious except 6N and 12N,the amplitude of the pulsation frequency in the low-frequency range was significantly reduced,and the integral pulsation amplitude was significantly smaller than that under the other two operating conditions.关键词
混流泵/压力脉动/傅里叶变换/大涡模拟Key words
mixed-flow pump/pressure pulsation/Fourier transform/large eddy simulation分类
机械制造引用本文复制引用
张琳,施卫东,张德胜,石磊..基于大涡模拟的混流泵不稳定流动数值研究[J].排灌机械工程学报,2017,35(4):303-308,318,7.基金项目
国家自然科学基金资助项目(51579118,51479083) （51579118,51479083）
江苏省产学研前瞻性联合研究项目(BY2015064-08) （BY2015064-08）
