The pressure characteristics analysis of oil pulsation flow based on VMD

Abstract

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.

VMD analysis of pulsating flow pressure signal of oil with different particle concentration

“…According to the non-stationary signal feature of multi-scale, quasi-periodic of the oil pulsation flow, we analyzed the pressure characteristics of oil pulsation flow based on VMD. 26 In this paper, The VMD method was used to analyze and process the pressure fluctuation signal of oil containing different particle concentrations. Therefore, the outline of the rest of this paper is as follows.…”