Abstract：Pressure fluctuation signals of a centrifugal pump inlet under different effective net positive suction head available (NPSHa) conditions were measured using dynamic pressure sensors.The3-layer 8-band wavelet packetdecomposition was done for the pressure signals.Wavelet packet decomposition coefficients were taken as time series to calculate 3 chaotic characteristic parameters including the maximal Lyapunov exponent, correlation dimension and K2 entropy.These parameters’ features and changelaws were analyzed and discussed.Results showed that the first 3 of decomposition coefficients in 8-band all have typical chaotic features; 3 chaotic characteristic parameters can be used to describe the system’s chaotic characteristics from different angles, and divide cavitation conditions corresponding to different NPSHa values into 4 different cavitation stages.
梁超，周云龙，杨宁，刘起超. 离心泵入口压力在汽蚀工况下的分频带混沌特性研究[J]. 振动与冲击, 2020, 39(23): 71-77.
LIANG Chao, ZHOU Yunlong, YANG Ning, LIU Qichao. Chaotic characteristics of multi-frequency band of centrifugal pump inlet pressure under cavitation condition. JOURNAL OF VIBRATION AND SHOCK, 2020, 39(23): 71-77.
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