|Table of Contents|

Structure and Development of Clusters in the Circulating Fluidized Bed Riser(PDF)

南京师范大学学报（工程技术版）[ISSN:1006-6977/CN:61-1281/TN]

Issue:
2020年03期
Page:
15-21
Research Field:
动力工程及工程热物理
Publishing date:

Info

Title:
Structure and Development of Clusters in the Circulating Fluidized Bed Riser
Author(s):
Chen Yuhang1; 2; Lu Shibing1; 2; Hu Junjun1; 2; Yin Shangyi1; 2; Song Tao1; 2; Lu Ping1; 2
(1.School of Energy and Mechanical Engineering,Nanjing Normal University,Nanjing 210023,China)(2.Engineering Laboratory of Energy System Conversion and Emission Reduction of Jiangsu Province,Nanjing Normal University,Nanjing 210023,China)
Keywords:
circulating fluidized bed; particle cluster; high-speed video technology; image processing
PACS:
TK121
DOI:
10.3969/j.issn.1672-1292.2020.03.003
Abstract:
In order to study the formation and disintegration mechanism of particle clusters in a circulating fluidized bed riser,the dynamic evolution process of particle clusters,such as the cluster formation,development and dissipation in a circulating fluidized bed riser is reported by the high-speed video technology. The image processing technology is used to determine the cluster shape,size and record the clusters evolution from formation to breakup under various operating conditions. The results indicate that under the effect of the complex air flow in the circulating fluidized bed,the formation of clusters in different spatial positions is various. The clusters in side-wall regions are more than those in the center. Similarly,the clusters at the riser bottom are more than those in the upper part. In addition,clusters in the bed vary in the shape and can be divided into the U-shaped,the inverted U-shaped,the center-banded,the stick-wall strip,the comet-shaped,the dense-spherical and the double-core-shaped. The comet-shaped,the dense-spherical and the double-core-shaped clusters could change into each other in the movement process. The upward flowing inverted U-shaped and the comet-shaped clusters are majority in the center region of the riser,while the falling U-shaped and the stick-wall strip clusters are majority in the side-wall region. Furthermore,the clusters in the riser always lateral migrate.

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Last Update: 2020-09-15