高压密相气力输送煤粉流动状态识别方法

State recognition method of dense-phase pneumatic conveying of pulverized coal under high pressure

高压密相气力输送中煤粉流动状态的识别及其监测对于煤气化的安全稳定运行具有重要意义。提出一种基于阵列式静电传感器实现高压密相气固两相流动状态识别的新方法。采用EMD方法对阵列式静电传感器各电极静电信号分别进行多尺度分解,并对得到的多尺度静电信号进行样本熵和能量比计算,通过分析各电极静电信号的多尺度样本熵和多尺度能量比的分布实现对流场内颗粒流动稳定性及其状态的识别。试验结果表明:阵列式静电传感器多尺度样本熵的一致性能够表征密相气固两相流动状态的稳定性,多尺度能量比的一致性能够表征管内颗粒分布的状态;并且还揭示了静电信号低尺度分量(1,2尺度)包含悬浮流动颗粒信息,高尺度分量(3尺度以上)包含沿管底流动颗粒信息。

The stability and monitoring of dense-phase pneumatic conveying of pulverized coal under high pressure has a significant meaning for coal gasification engineering application.A novel array electrostatic sensor based method was presented to achieve the recognition of the flow stability and flow regime of dense gas-solid two-phase flow.Multi-scale decomposition was firstly performed for the electrostatic signals of every electrode of the array electrostatic sensor by EMD,and the sample entropy and energy ratio were calculated for every scale electrostatic signal component. Finally through the comparison and analysis of the multi-scale sample entropy and multi-scale energy ratio,the recognition of the particles flow stability and flow regime was achieved.The experimental results indicated that the consistency of the multi-scale sample entropy of the array electrostatic signals presents the stability of dense gas-solid two-phase flow,and the multi-scale energy ratios present the particles distribution and flow regime within pipeline;the low-scale components（1,2 scale） of the electrostatic signal contain the information of the suspended particles flow,and the high-scale components（3 scale above） contain the information of the great particles group flow along the bottom of the pipe.