Abstract: Almost all the literature correlations for predicting the minimum spout-fluidizing velocity, u_msf,were developed from single particle component and special gas-distributor,and hence have some limitation in actual application.In view of this,u_msf of binary particle mixtures were determined in a semi-cylindrical spout-fluid bed of 125 I.D. and 60° conical base angle. Since bed diameter and perforated distributor modes affect obviously the gas dispersion and the exchange between spout and annular region in spout-fluid beds, four functions, i.e.,cos(aθ),sin(bθ),tan(cβ) and f(D_c/D_cref),were proposed to represent the effects of conical angle,θ, uniform gas distribution style， holes orientation angle,β, and bed diameter,D_c, on u_msf, respectively.Based on 590 u_msf data from this work and literatures, six dimensionless numbers, standing for bed geometry, particle properties and momentum at minimum spout-fluidizing conditions, and the above four functions are satisfactorily used to develop a new correlation for predicting umsf with a correlation coefficient 0.97, a deviation ±29.5% and an average deviation 11.5%.

摘要： 在一Ф125 mm、锥角60°的喷动流化床内测定了混合和分离体系的混合二组分及其单一组分的最小喷动流化速度u_msf.实验表明，最小喷动速度随静床高增加而增大，随流化气速和浮升组分分率增大而减小；混合体系中最小喷动速度随浮升组分分率接近线性递减，而分离体系却呈曲线降低.对比分析了文献umsf数据，除喷口直径外，多孔分布板形式和床径明显影响u_msf的大小,采用cos(aθ)、sin(bθ)、tan(cβ)和f(D_c/D_cref)来分别修正分布板夹角θ、均匀布气结构、开孔方向角β和床径D_c的影响.根据本文和文献不同结构与体系的590组数据，又用6个量纲1参数和上述4个修正函数进行了多重影响因素的综合回归，得出新的预测u_msf的普适关联式，该式偏差±29.5%，平均偏差11.5%，相关系数0.97.