在内径为150mm,高度为5000mm的垂直立管实验装置上,以流化催化裂化催化剂为颗粒物料,采用颗粒速度测量仪测量颗粒下行流动的速度;类比流体力学中的层流和湍流,采用颗粒雷诺数准数来划分垂直立管中下行颗粒流的流态。结果表明:垂直立管中下行颗粒流存在3个临界雷诺数Rep1、Rep2和Rep3;根据颗粒流雷诺数的大小,可将立管内的颗粒流动行为划分为4种流态,即间歇式密集流、波动式密集流、密集流向稀疏流的过渡.以及稀疏流状态。
The particle down flowing velocity in an experimental standpipe with internal diameter of 150 mm and height of 5 000 mm was measured by a particle velocity measuring instrument. The particle materials used in the experiment were fluid catalytic crack(FCC) catalysts. Making an analogy with laminar flow and turbulent flow in fluid mechanics, Reynolds number of the granular flow in the standpipe was used to determine the granular flow pattern. The results show that in the standpipe there are three critical Reynolds numbers which are Rep,.Rep2. and Rep3. The flow behavior of granular in the standpipe can be classified as four flow patterns depending on Reynolds number, namely, intermittent dense flow, fluctuating dense flow, transitional period from dense flow to dilute flow, and dilute flow status.