摘要
流化床内颗粒的混合对流化床内颗粒运行以及燃烧有重要的影响 ,因此 ,利用图像处理技术在二维流化床试验装置上研究了水煤膏的混合过程 ,分析了气固两相射流的流动特性 ,利用R/S分析方法表明了气固两相射流的脉动特性。实验发现从喷嘴喷入的水煤膏聚集在射流水平段顶端 ,并且随射流的脉动而脉动 ,在射流和气泡的作用下 ,水煤膏将发生变形、扩散以及混合。并利用数字图像相关性分析方法得到了水煤膏在流化床内的混合过程 ,指出在流化床不同区域水煤膏混合机理不同 ,在射流影响区底部 ,由于射流脉动以及携带作用使水煤膏颗粒混合 ;在射流影响区上部以及射流影响区以外 ,射流气泡以及流化气泡的运动导致水煤膏颗粒混合 ,并且发现由于射流的引入使颗粒的内循环运动加强。
The mixings of particle in fluidized bed have an important effect on moving and combustion of particle.The mixing of CWP (Coal Water Paste) in the two dimensional fluidized bed with jet was investigated by digital image processing. The characteristics of gas solid jet are researched and the characteristics of gas\|solid jet fluctuation are proved by means of Rescaled Range Analysis. The CWP congregates in the top of horizontal part of the jet and fluctuates with the jet. The CWP distorts,diffuses and mixes because of bubbles and jet fluctuation.The mixing of CWP was investigated by the correlation analysis of digital image. There are different mixing mechanisms in the different regions.The CWP mixes in the bottom region of jet\|effect area by jet fluctuation and jet daggling,in the top and out region of jet\|effect area by jet bubble moving and fluidized bubble moving.The gross circulation is strengthened because of presence of jet.
出处
《中国电机工程学报》
EI
CSCD
北大核心
2001年第12期41-44,62,共5页
Proceedings of the CSEE
基金
高等学校博士学科点专项科研基金资助项目( 95 2 860 4)
关键词
水煤膏
射流流化床
燃烧
图像处理
two dimensional fluidized bed
jet
CWP
mixing
fluctuation
