基于Hilbert-Huang变换的混流泵流动诱导振动试验  

Experiment of flow induced vibration of mixed-flow pump based on Hilbert-Huang transform

作　　者：李伟[1] 季磊磊 施卫东[1] 杨勇飞[1] 平元峰 张文全[1] 

机构地区：[1]江苏大学国家水泵及系统工程研究中心,镇江212013

出　　处：《农业工程学报》2018年第2期47-54,共8页Transactions of the Chinese Society of Agricultural Engineering

基　　金：国家自然科学基金项目(51679111;51579118);江苏省自然科学基金项目(BK20161472);江苏高校优势学科建设工程资助项目(PAPD)

摘　　要：混流泵水力诱导的机组振动是混流泵运行失稳的重要因素之一,为了研究混流泵水力激振诱导的机组振动情况,基于本特利408数据采集系统,测量获得了空载和负载工况下混流泵泵体和泵体基座不同位置处的振动信号,通过希尔伯特-黄变换对原始振动信号进行经验筛分分解,获得了不同模函数分量的频谱分布。研究结果表明,相比空载运行,混流泵负载工况运行时水力诱导的机组振动明显加剧,但在不同方向上,水力激振引起的振动各不相同。X方向上2个工况下的振动频谱分布基本相似,而在Y方向、Z方向和混流泵底座上,负载工况下波形的频带分布变窄,能量分布较为集中,且Z方向的原始振幅要明显大于Y方向,约为Y方向原始振幅的2倍。混流泵负载工况运行时,低频振动占据主要振动能量分布,使得不同模函数分量的主频向低频方向移动,水力诱导混流泵机组的振动以中低频振动为主。该研究可为有效降低或防止混流泵水力诱导的机组振动恶化提供参考。The vibration induced by flow is one of the important factors to the instability of the mixed-flow pump.With the increase of the capacity and the size of mixed-flow pumps,the vibration of the hydraulic components attracts more attention from researchers and engineers.In order to study the vibration of mixed-flow pump induced by hydrodynamic force,based on the Bentley 408 data acquisition system,vibration signals in 3 directions（X,Y and Z） on the base under unloaded and designed flow conditions of the mixed-flow pump are tested and then analyzed using Hilbert-Huang transform（HHT）.The original vibration signal is decomposed by EMD（empirical mode decomposition） using the Hilbert-Huang transform,and the spectral distribution of the different mode function components is obtained.The decomposed signal contains intrinsic modulus with 11 different orders and one residual.The acquired intrinsic modulus represents vibration signal with different frequencies,except the Intrinsic mode function 11 and the residual,which show no periodic characteristics.The results show that the vibration under loaded condition is significantly increased compared with the unloaded operating condition,but the vibrations caused by the hydraulic excitation differ in different directions.When the mixed-flow pump is working under designed operating condition,the low frequency vibration occupies the main vibration energy distribution,making the main mode of the different mode function components move to the low frequency direction,and the hydraulic induced vibration is dominated by the middle and low frequency vibration.In the X direction,the vibration spectrum distribution is similar in the 2 cases,while in the Y and Z direction and on the base of mixed-flow pump the frequency distribution of the waveform is narrowed and the energy distribution is concentrated under loaded condition.Under both loaded and unloaded conditions,the main frequency of the spectrum moves toward the low frequency region with the increase of the modulus order.Th

关 键 词：泵 振动 信号分析 混流泵 空载 希尔伯特-黄变换 

分 类 号：TH313[机械工程—机械制造及自动化]