气固流化床压力脉动信号的Hilbert-Huang谱分析

PRESSURE-FLUCTUATION ANALYSIS OF GAS-SOLID FLUIDIZED BEDS USING HILBERT-HUANG TRANSFORM

首次将Hilbert Huang变换 (HHT)应用于气固流化床压力脉动信号的分析 ,提取并研究了压力脉动信号中隐含的表征复杂的粒子运动与气泡运动相互调制的非线性特征 ,以及压力脉动信号高、低阶内禀模态函数(IMF)之间的能量转换与流化床的流化状态相对应的新信息 ,在此基础上提出了采用压力脉动IMF分量的能量转移现象进行颗粒结块故障判别的新方法 .结果表明 ,应用Hilbert Huang谱对压力脉动信号分析的新方法能比现有的分析方法提供更多的有用信息 ,有助于更深入地揭示床内非线性流体动力学特征 .

In this paper the Hilbert-Huang Transform (HHT) is applied to analysis of the pressure-fluctuation in gas-solid fluidized beds for the first time.By using this new nonlinear and non-stationary signal-processing method to analyze the pressure fluctuation signals, nonlinear intermodulation characteristics in complicated movement of particles and bubbles were revealed, new information such as the corresponding relations of energy-transmission between different orders of Intrinsic Mode Functions (IMFs) and operating conditions of gas-solid fluidized beds was extracted as well.Based on it, a new method, with which the energy-transmission between IMFs of pressure fluctuations can be used to detect particle agglomeration,was developed in this study.Research results showed that this new method based on HHT could provide more useful information and expose the nonlinear fluid dynamics features in fluidized beds more clearly than other analysis methods available.