Particle velocity profiles in a circulating fluidized bed riser of square cross-section
Particle velocity profiles in a circulating fluidized bed riser of square cross-section
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DOI：
10.1016/0009-2509(94)00241-i
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发表时间：
1995
影响因子：
4.7
通讯作者：
J. Zhou;J. Grace;C. J. Lim;C. Brereton
中科院分区：
文献类型：
--
作者：
J. Zhou;J. Grace;C. J. Lim;C. Brereton
在146 mm × 146 mm方形截面的循环流化床提升管中，采用五光纤颗粒速度测量系统，测量了提升管中颗粒的垂直速度和上升、下降的颗粒份额。表观气速和固体循环速率示出影响颗粒速度和向上移动的颗粒的分数的横向和轴向的配置文件。外环向下流动区域的厚度首先随高度减小，直到达到最小值，然后向立管顶部变厚。由于出口效应的影响，提升管顶部颗粒速度的横向分布是不对称的，并且壁面下行流层在出口相对侧比出口侧厚。角落也被发现是更大的下流区域。
A five-fibre optical particle velocity measuring system was used to determine vertical velocities and the fractions of rising and falling particles in a circulating fluidized bed riser of 146 mm × 146 mm square cross-section. The superficial gas velocity and solids circulation rate are shown to affect lateral and axial profiles of particle velocity and the fraction of particles moving upwards. The thickness of the outer annulus downflow region first decreased with height until a minimum was reached and then became thicker towards the top of the riser. Because of the exit effect, lateral profiles of particle velocity were asymmetric at the top of the riser and the wall downflow layer was thicker on the side opposite to the exit than on the exit side. The corners were also found to be regions of greater downflow.