MOTION BEHAVIOR OF LARGE OBJECTS OF DIFFERENT SHAPES IMMERSED IN A FLUIDIZED BED
In many applications of fluidized bed, large and dense objects may be captured in the stagnant zones over the distributor.Their motion patterns in the dense zone of the bed have a paramount effect in the performance of the reactor.In this paper, a series of experiments were conducted to study the residence time and the motion trajectory characteristic of spherical, cylindrical and cubic objects in the fluidized bed at various superficial gas velocities using Electrical Capacitance Tomography (ECT) tracing technique.The objects were much larger and denser than the fine particles of the dense phase.Experimental results show that the residence time of the spherical object in the fluidized bed is the largest and the cubic one is the smallest in all cases.With the increasing of the gas velocity and the object size, the time differences reduce.Typical trajectories of the objects reveal that the spherical objects are easy to be disrupted when in motion over the air distributor, leading to a long residence time.Mechanical model analysis show that the drag force and the sum of pressure distribution on the whole object vary with object shapes and then their motion state and residence time in the bed.
Rongrong Cai Yanguo Zhang Qinghai Li Aihong Meng
Key Laboratory for Thermal Science and Power Engineering of Ministry of Education,Beijing Key Laboratory for CO2 Utilization and Reduction Technology,Department of Thermal Engineering,Tsinghua University,Beijing 100084,China
国际会议
The 11th International Conference on Fluidized Bed Technology(CFB-11)(第十一届流化床技术国际会议)
北京
英文
199-204
2014-05-14（万方平台首次上网日期，不代表论文的发表时间）