导向管充气喷动床的流动与传热特性研究

Flow and Heat Transfer Characteristics of Draft Tube Spouted Bed with Aeration

在直径９２ｍｍ的有机玻璃制导向管充气喷动床反应器内，以玻璃珠为实验物料，以空气为喷动和充气气体，在导向管充气喷动床的最大允许充气速度范围内，考察充气速度对导向管充气喷动床的最小喷动速度、床层压降、中心喷泉高度的影响．采用示踪粒子的方法，研究充气速度对颗粒在壁效应区的下移速度的影响．并考察了热模装置内充气速度对壁与床层间传热系数的影响．结果表明：充气有利于导向管喷动床的喷动及操作稳定性；充气有利于颗粒的循环；并能提高壁与床层间的传热系数．综合考虑床层的几何尺寸以及气体和固体的物性，并根据实验数据，得到了导向管充气喷动床的最小喷动速度关联式，为其设计和操作提供参考．

The effect of aerating rate on the minimum spouting velocity,bed pressure drop,spouting height was investigated in a draft tube spouted bed with aeration made of a plexiglass cylinder with inside diameter of 92 mm by using glass beads as experimental materials,and air as spouting and aerating fluid.Within the maximum allowed aerating velocity of draft tube spouted bed with aeration,the effect of aerating velocity on particle down coming rate in the region of wall effect was studied by using tracer particles.The effect of aerating velocity on the wall-to-bed heat transfer coefficient was studied in a heat mode apparatus.Result indicates that aeration is beneficial to the operation and spouting stability;and beneficial to the particle circulation;and that the wall-to-bed heat transfer coefficient was improved.The correlation used to calculate the minimum spouting velocity of draft tube spouted bed with aeration was obtained by regressing experimental data.It is useful for design and operation of a draft tube spouted bed with aeration.