Liu Ge, Chen Bin
School of Environmental Engineering, North China Institute of Science and Technology, Hebei, 065201, China.
School of Mechanical and Electrical, Hebei Key Laboratory of Safety Monitoring of Mining Equipment, North China Institute of Science and Technology, Hebei, 065201, China.
Sci Rep. 2021 Aug 30;11(1):17390. doi: 10.1038/s41598-021-96860-0.
The pressure signal of oil pulsating flow is a kind of multi-component signal; in order to realise the effective separation of the multi-component pressure signal and extract its vibration characteristics, the pressure signal was decomposed by Variational Mode Decomposition (VMD). The slope criterion of the centre frequency is proposed to determine the number of components of VMD decomposition, and the method to judge the main components of the signal by energy value is proposed. The Hilbert envelope demodulation analysis was performed on the main components obtained. The results show that the proposed center frequency slope criterion method is effective in the VMD decomposition of the pressure signal of oil pulsating flow, which is used to decompose the pressure signal into 9 components. Four major components of the pressure signal are obtained by the correlation between each component and the pressure signal, and the energy value calculation of each component. The main component frequency of the pressure signal is one time, 6 times, 11 times and 14 times the frequency of the system spindle rotation; these are the sum of two cosine signals of close frequency and have the characteristic of beat vibration.
油脉动流压力信号是一种多分量信号；为实现多分量压力信号的有效分离并提取其振动特性，采用变分模态分解（VMD）对压力信号进行分解。提出了中心频率斜率准则来确定VMD分解的分量数，并提出了通过能量值判断信号主要分量的方法。对得到的主要分量进行了希尔伯特包络解调分析。结果表明，所提出的中心频率斜率准则方法在油脉动流压力信号的VMD分解中是有效的，该方法将压力信号分解为9个分量。通过各分量与压力信号的相关性以及各分量的能量值计算，得到了压力信号的四个主要分量。压力信号的主要分量频率分别为系统主轴旋转频率的1倍、6倍、11倍和14倍；这些是频率相近的两个余弦信号之和，具有拍振特性。
