不同颗粒浓度油液压力振动信号特征的HHT提取  

Extraction for HHT features of pressure vibration signals of oil pulsating flow with different particle concentration

作　　者：陈彬 刘阁 CHEN Bin;LIU Ge(School of Mechanical&Electrical,North China Institute of Science and Technology,Yanjiao 065201,China;School of Environmental Engineering,North China Institute of Science and Technology,Yanjiao 065201,China)

机构地区：[1]华北科技学院机电工程学院,河北燕郊065201 [2]华北科技学院环境工程学院,河北燕郊065201

出　　处：《光学精密工程》2019年第11期2484-2497,共14页Optics and Precision Engineering

基　　金：国家自然科学基金资助项目(No.51375516);重庆市基础研究与前沿探索项目资助(No.cstc2018jcyjAX0121);重庆市技术创新与应用示范项目资助(No.cstc2018jscx-msybX0335);中央高校基本科研业务经费项目资助(No.3042019001)

摘　　要：颗粒浓度对油液的湍流脉动特性有一定的影响,利用Hilbert-Huang变换方法对含不同颗粒浓度的油液脉动流的压力信号进行分析,探讨颗粒浓度对压力信号的振动特征的影响规律。利用经验模态函数(EMD)、Hilbert变换和包络解调等方法,获取压力信号的Hilbert谱和信号能量特征,分析了不同颗粒浓度的油液压力信号的能量分布和调幅调频特征以及调制信号的瞬时频率。结果表明以IMF能量作为特征向量将各阶IMF分量划分为3个信号特征频带,随着颗粒浓度的增加,高频率区的累积分布基本稳定在0.7范围内,而中频率区出现下降、低频率区呈现上升的状态;高频率区的边际谱平均幅值随着油液中颗粒浓度的增加呈现先增加后降低的发展趋势,中低频率成分的幅值呈增加的趋势;对压力信号在不同频带内的瞬时能量谱进行积分,得到压力信号的总能量随着颗粒浓度的增加出现下降趋势,中频率区的能量特征值呈逐渐衰减的变化趋势;含不同颗粒浓度的油液压力信号具有调制特征,Hilbert包络解调信号的瞬时频率均值呈先增加后下降的发展趋势。Particle concentration has any effect on turbulence characteristics of the oil,by using Hilbert-Huang method,the pressure signal of oil pulsating flow with different particle concentration was analyzed,and the law of particle concentration effect on vibration characteristics of pressure signal was discussed.Using empirical mode function,Hilbert transform and envelope demodulation method,the Hilbert spectrum and energy characteristics of oil pressure signal was obtained,analyzes the energy distribution of the pressure signal of oil containing different particle concentration,and the characteristics of frequency modulation and amplitude modulation,and the instantaneous frequency of the modulating signal were analyzed.The results showed that each intrinsic mode function(IMF)component is divided into three signal characteristic bands as the characteristic vector using IMF energy;with particles concentration increased,the time variation of the each order IMF component of pressure signal of oil pulsating flow of develops gradually from high band of modulation features to low band,cumulative distribution of high-frequency district of marginal spectrum of pressure signal stables basically range within 0.7.Moreover,as the middle-frequency district decreased,the low-frequency district tended to increase.The average amplitude of the high-frequency district of the marginal spectrum rendered first increased and then decreased as the particle concentration of oil increased,and the amplitude of the middle-and low-frequency components increased.The instantaneous energy spectrum of the pressure signal in different frequency bands was integrated to obtain the total energy of the pressure signal that decreased as particle concentration increased and the energy characteristics of the middle-frequency district declined.Oil pressure signals with different particle concentrations have modulation characteristics.The instantaneous frequency mean value of the Hilbert envelope demodulation signal first increased and then decreased.

关 键 词：脉动流 HHT 压力振动信号 特征提取 颗粒浓度 

分 类 号：TH741[机械工程—光学工程] O357.4[机械工程—仪器科学与技术]