底饲进料循环喷动床内压力脉动信号的SHANNON信息熵分析

为了研究底饲进料循环喷动床内气固两相流的流动特性,通过冷态实验测量反应塔内轴向不同高度上的压力脉动信号.应用SHANNON信息熵分析压力信号,并比较不同操作条件对塔内气固流动的影响.结果表明:压力脉动及其功率谱在不同床层高度上表现出不同的特性;SHANNON信息熵能够很好地反映特征信号的复杂程度和稳定程度;提高流化速度和循环倍率能够导致塔内轴向上的颗粒浓度上升,从而使压力脉动的幅度增加;提高喷射速度和喷嘴位置,能使反应塔底部气固湍动更加强烈,SHANNON信息熵随之上升.

A Shannon Information Entropy Analysis of Pressure Fluctuation Signals From an Underfed Circulating Spouted Bed

To study the gas-solid two phase flow characteristics of an underfed circulating spouted bed,the authors have measured the pressure fluctuation signals at various heights in the axial direction of a reaction tower through a cold-state test,analyzed the pressure signals by using Shannon information entropy and compared the influence of different operating conditions on the gas-solid two-phase flow in the tower.It has been found that the pressure fluctuation and its power spectrum display different characteristics at different heights of bed layers and Shannon information entropy can reflect very well the complexity and stability degree of the characteristic signals.Enhancing the fluidized velocity and circulation ratio can lead to an increase of particle concentration in the axial direction of the tower,thus enhancing the amplitude of the pressure fluctuation.To increase the jet flow velocity and heighten the nozzle location can intensify the gas-solid turbulent flow at the bottom of the tower and Shannon information entropy can be increased accordingly.