摘要
研究了在直径 4.2cm、高 130cm的垂直三相流化床中固体颗粒非粘附与粘附两种不同体系中固含率的分布特性 .基于混合长理论与实验数据 ,提出了将“沉降 -扩散”模型同时应用于描述非粘附与粘附体系 (进行气速的修正 )中固含率的轴向分布 。
In a vertical gas-liquid-solid fluidized bed of 4.2 cm in diameter and 130 cm in height, the axial solid concentration distribution is investigated for two kinds of particles with different properties. Two distinguishing systems can be formed upon the wettable property of particle materials. One is called as a no-attached system, in which the solid holdup decreases with the increase of bed height. Another is named as an attached system, in which solid holdup increases with the increase of bed height. The sedimentation-dispersion model can be employed better to describe both above systems by modifying only one model parameter, i.e. the particle terminal settling velocity, which considers the effect of an additional drag force resulting from attached up-flowing bobbles and subtracts a certain value obtained by a function formula relating to the gas velocity. It is found that the axial concentration profiles of solid particles predicted by the modified sedimentation-dispersion model are in good agreement with experimental results for both no-attached and attached systems.
出处
《化工学报》
EI
CAS
CSCD
北大核心
2001年第2期108-113,共6页
CIESC Journal
基金
福建省教委资助项目!(No.JB990 40 )
