撞击流反应器流场速度时间序列的结构复杂性研究  

Structural Complexity Study for the Velocity Time Series in Impinging Stream Mixer

作　　者：张建伟[1] 宋艳芳[1] 

机构地区：[1]沈阳化工大学机械工程学院,沈阳110142

出　　处：《机械工程学报》2011年第22期174-180,共7页Journal of Mechanical Engineering

基　　金：辽宁省自然科学基金(20102179);辽宁省高等学校优秀人才支持计划(2008RC40)资助项目

摘　　要：结合谱熵和小波熵算法,从整体及各个尺度上,对撞击流反应器(Impinging stream mixer,ISM)流场速度时间序列进行结构复杂性分析。谱熵算法描述时间序列信号的谱的结构情况,反映序列频率谱的集中程度,从而体现ISM流场速度信号的总体的平均功率的分布情况;小波熵算法充分利用小波变换的多分辨、多尺度特性,使信号在结构上的复杂性得以清晰体现。研究表明,尺度a4上的小波熵分布与系统的结构复杂性的分布类似,说明该系统的信号的主要特征集中在低频细节成分a4尺度上。不同尺度下的小波熵表征信号在各个频段的变化趋势,体现信号在时域和频域上的信息。该系统的轴向流体结构复杂性大小沿轴线没有特定的变化规律,但径向流体结构复杂性大小呈对称分布,且在轴心取得最大值。Structural complexity is first to use for the velocity time series in the field of impinging stream mixer（ISM）from the whole to each scale,combining spectral entropy with wavelet entropy algorithm.Spectral entropy algorithm depicts the structure of spectrum in the time series signal,reflecting the sequence of concentration of the frequency spectrum,which reflects the distribution of the overall average power for signal in ISM.To reflect the complexity of the signal in structure clearly,full advantage of the multi-resolution,multi-scale features of the wavelet transform are taken.The results indicated that the distribution of a4-scale wavelet entropy and the distribution of system complexity have similar structure,which indicates that the main character of the signal concentrated in the low-frequency detail components of a4.The wavelet entropy under different scales represent the tendency of the signal in every frequency range,reflecting the information of the signal in time and frequency domain.The structural complexity of the axial flow has no specific law along shaft line,but the radial is symmetric and get the maximum value in the core.

关 键 词：撞击流 结构复杂性 谱熵 小波熵 

分 类 号：TQ52[化学工程—煤化学工程]