柱锥体喷动床喷动特性的试验研究

Experiment Study of Spout Characteristics of a Cone-Base Cylindrical Spouted Bed

建立了高1500 mm、内径200 mm、锥角60°、喷口直径可变的可视化柱锥体喷动床系统,进行了五种不同颗粒喷动特性的试验,重点考察了床层压降、最小喷动速度和喷泉高度随操作参数的变化。结果表明:升速法与降速法测得的最小喷动速度具有较大的差异,降速法测得的最小喷动速度与经验关联式的计算值吻合较好;最小喷动速度随着静止床高、颗粒直径、喷口直径的增大而变大;随着表观气速的增加,喷泉高度上升,随着静止床高的增加,喷泉高度下降。

Experiments of spout characteristics of five different materials have been carried out in a cone-base cylindrical spouted bed with 1500 mm in height,200 mm in diameter,a cone angle of 60°and a variable spouted nozzle.The changes of pressure drop,the minimum spouting velocity and the fountain height with the operating parameters are discussed.The results show that the minimum spouting velocity measured by acceleration method is quite different from the one measured by deceleration method,and the latter one is consistent with the calculation of the empirical correlation. The minimum spouting gas velocity increases progressively with the increasing of static bed depth, particle diameter and spout nozzle diameter.The fountain height increases as the spouting gas velocity increases,and decreases as static bed depth increases.