Influence of pump start-up mode on the stability of mixed-flow pumps

• Published in: Journal of mechanical science and technology 2023, 37(6), , pp.2949-2958
• Main Authors: Tang, Zhenbo, Zhu, Guojun, Feng, Jianjun, Wu, Yajun, Liu, Kai, Lu, Qiang
• Format: Article
• Language: English
• Subjects: Angular acceleration; Coherence analysis; Control; Dynamical Systems; Engineering; External pressure; Flow generated vibrations; Flow stability; Guide vanes; Impellers; Industrial and Production Engineering; Low frequencies; Mechanical Engineering; Original Article; Process parameters; Stability analysis; Time-frequency analysis; Vibration; Wavelet analysis; 기계공학
• ISSN: 1738-494X; 1976-3824
• DOI: 10.1007/s12206-023-0521-7

To analyse the influence of the start-up mode on the stability of the mixed-flow pump, start-up experiments are performed. And the external characteristic parameters, pressure fluctuation and shaft vibration data are collected by a multi-channel synchronous signal acquisition system during start-up. These data are analyzed by the time-frequency analysis method and wavelet partial coherence analysis method. Results reveal a positive correlation between the impeller angular acceleration and the time change rate of external characteristic parameters. During the start-up process, the variation law of the external characteristic parameters similar with the law of impeller rotating speed rise. The amplitude of the shaft vibration has a positive correlation with the start-up acceleration of the impeller. The influence of guide vane pressure fluctuations on the shaft vibrations is greater within 0∼2 s after the start of the mixed-flow pump. With the strart-up time extension, the partial coherence between the shaft vibration and the pressure fluctuations in guide vane is enhanced in low frequency band, which increases the risk of flow-induced vibration of the pump shaft.