CFB密相区内颗粒横向扩散对燃烧的影响

循环流化床(CFB)床内燃料颗粒的扩散、混和，特别是复杂的密相区内的混和特性在很大程度上影响了燃烧状况，密相区颗粒横向扩散的规律，对于循环流化床的设计具有重要意义，在循环流化床密相区颗粒横向扩散实验研究的基础上，总结了密相区内颗粒横向扩散系数的经验公式，以此为基础，研究了密相区内碳的分布规律，并建立了相应的燃烧模型，模型包括两个子模型，即密相区二维流动及燃烧子模型、稀相区一维流动及燃烧子模型。通过模型定性模拟了流化风速、给料点布置对床内燃烧的影响，有效地反映了实际情况，并确认了将密相区颗粒横向扩散规律引入现有循环流化床燃烧模型的重要意义。

EFFECT OF THE SOLID LATERAL DISPERSION IN THE DENSE ZONE OF CFB

The mixing of fuel particles,especially in the dense zone of CFB,has a great effect on combustion.The rule of solid lateral dispersion in dense zone is very important in CFB design.Based on the experiments of lateral solid mixing in the dense zone of CFB reactor,empirical expressions of the lateral dispersion coefficient are summarized in the present paper.Thus the carbon distribution is studied with the aid of solids combustion model in CFB.The combustion model consists of two sub-models:the two-dimensional model in the dense zone and the one-dimensional cell model in the dilute zone.The rusults of simulation can give a criterion for the fluidized gas velocity and the distribution of coal feeders,which qualitatively agree with the reality and confirm the significance of the modeling method.