振动流化床床层压降理论分析与实验研究

Theoretical Analysis and Experimental Research of the Bed Pressure Drop in Vibrated Fluidized Bed

从振动流化床床层压降的物理意义出发,得出了振动流化床床层压降模型。提出振动流化床床层压降-流速曲线上存在第一、第二流化段,相应速度为第一、第二临界流化速度。并在二维振动流化床内,以不同粒径的玻璃珠为床料进行了实验研究,分析了振动及其它操作条件对床层压降的影响,并将模型计算得到的压降与实验结果进行了比较,结果表明模型预测与实验结果有较好的一致性。实验关联了振动能量传递系数的数学表达式,得到第一、第二临界流化速度时床层压降,并与其他研究者的结果进行了对比分析,结果显示本文的模型能得到更为可靠的预测结果。

A mathematical model was proposed to predict the pressure drop of vibrated fluidized bed based on the physical significance of the pressure drop of the bed. The first and second fluidization phases including their corresponding critical fluidization velocities were putted forward from the kinetic characteristic of the vibrated fluidized bed. Experiments by using glass beads with different diameter were carried out in the two-dimensional vibrated flu- idized bed. The influence of vibration and operation conditions on the pressure drop of vibrated fluidized bed was analyzed. Comparing the model predictions with the experimental data, it showed that the data of theoretical prediction with model were in good agreement with experimental data. An empirical correlation equation to predict the coefficient of vibration energy transfer was established according to the experimental data. The pressure drops of the bed at the first and second critical fluidization velocity were gained. In the end the results obtained in this paper were compared with those of other researchers, which indicated that the model of this research could obtain more reliable result.