增压富氧循环流化床的二维流动模型  

Two-dimensional hydrodynamic modeling of pressurized oxy-fuel CFB

作　　者：刘慧敏[1] 白彦飞[1] 乔木森[1] 雷鸣[1] 王春波[1] 

机构地区：[1]华北电力大学能源动力与机械工程学院,河北保定071003

出　　处：《华北电力大学学报（自然科学版）》2014年第3期107-112,共6页Journal of North China Electric Power University：Natural Science Edition

基　　金：河北省自然科学基金资助项目(2013502292)

摘　　要：建立了增压富氧循环流化床的二维流动模型，将增压富氧循环流化床炉膛分为下部密相区和上部稀相区，同时考虑气固轴向和径向变化。模型针对3002／70再循环烟气（RFG）富氧气氛，5mm颗粒粒径，在温度范围20～1000℃，压力范围0．1～6．0MPa下，计算了增压富氧循环流化床的流动特性，主要分析压力和温度对临界流化速度Umf的影响以及压力对环形区厚度6，床层空隙率8和颗粒浓度分布8。的影响。计算结果表明：随着压力的升高，临界流化速度不断减小，环形区厚度变薄，空隙率降低，颗粒浓度增大。随着温度的升高，临界流化速度先增大后减小，且床层压力越大，迭到峰值所需的温度越高。A two-dimensional hydrodynamic model of pressurized oxy-fuel CFB is developed in this paper. In the modeling the CFB riser is divided into two regions, the bottom zone and the upper zone. The model also takes into account the axial and radial distribution of bed voidage and solid volume fraction. Parameters used in the hydrodynamic calculation are as follows： 30 02/70 RFG atmosphere, mean particle diameter 5mm, temperature from 20 to 1 000 ℃ , pressure from 0.1 to 6.0 MPa. The model result shows that with the increasing of system pressure, the annular zone thickness gets thinner, bed voidage decreases and solid volume fraction increase simultaneously. As the pressure increases, a noticeable decline of Urn： is observed. However, for a fixed pressure, Umf increases firstly and reduces afterward with the increase of temperature, and the corresponding temperature of Umf peak becomes higher with increasing pressure.

关 键 词：增压富氧燃烧 循环流化床 压力 流动 二维模型 

分 类 号：TK16[动力工程及工程热物理—热能工程]