变工况对侧壁式离心泵振动特性的影响  

Influence of Operating Condition on the Vibration Characters of a Centrifugal Pump With Slope Volute

作　　者：张宁[1] 杨敏官[1] 高波[1] 李忠[1] 倪丹[1] 

机构地区：[1]江苏大学能源与动力工程学院,镇江212013

出　　处：《工程热物理学报》2015年第7期1471-1475,共5页Journal of Engineering Thermophysics

基　　金：国家自然科学基金资助项目(No.51206063;No.51476070);江苏省高校优势学科建设工程项目(PAPD)

摘　　要：振动是离心泵关键性能指标,低振动离心泵设计是目前研究的难点问题。本文对具有特殊结构的侧壁式压水室离心泵振动特性进行实验研究,分析了不同流量下,模型泵重要测点处振动频谱和能量的变化特性。结果表明:变工况对模型泵的中、高频信号影响较小,不同流量下低频振动能量变化明显,因此水力因素主要诱发低频振动信号;加速度频谱图中,叶频处的幅值较小,峰值信号出现在叶频的高次谐波处;低频段振动能量和泵内流场结构密切相关,非设计工况下,泵内容易出现非稳态流动结构,造成泵的振动能量不断上升;尤其在小流量工况,旋转失速导致泵的振动能量迅速增加;通过对振动能量曲线分析初步提出了低频振动能量和流量的特征函数关联式,为预测变工况对泵振动特性的影响提供理论依据。Vibration energy is vital to the performance of the centrifugal pump, and low vibration of the centrifugal pump is the difficult problem during pump design. In the present study, vibration experiment of a centrifugal pump with slope volute is conducted, and vibration signals at different measuring points are investigated for various flow rates. Results show that the influence of operating condition on middle and high frequency signals is not significant, and it has an obvious effect on low frequency signals. So flow dynamics induced vibration signals mainly concentrate in low frequency band. In acceleration spectrum, peak at fBPF is not evident, and high spike occurs at the high harmonic of fBPF. Besides, low frequency signals are closely associated with the flow structures inside the pump. At off-design conditions, due to the occurring of unsteady flow structure, vibration energy would increase rapidly, especially at low flow rate, rotating stall would lead to vibration increasing steeply. The functions between operating condition and vibration energy are carried out, and it would be useful to predict vibration level under different conditions.

关 键 词：离心泵 侧壁式压水室 加速度频谱 振动能量 

分 类 号：TH311[机械工程—机械制造及自动化]