双支腿流化床颗粒压力脉动及翻床现象数值模拟  

Numerical Simulation of Particle Pressure Fluctuation and Bed Overturn in Coarse Particle Dual-fluidized Bed

作　　者：郑建祥[1] 谷春雨[1] 王建江[1] 

机构地区：[1]东北电力大学能源与动力工程学院

出　　处：《电站系统工程》2015年第2期20-22,26,共4页Power System Engineering

基　　金：吉林省科技发展计划项目(201101109)资助

摘　　要：采用欧拉-欧拉模型,对双支腿流化床内颗粒压力脉动及翻床现象进行仿真模拟,利用功率谱密度和小波分析方法对数据进行分析,结果表明:双支腿流化床内颗粒产生压力脉动主要原因是气泡的生成破裂及两侧床腿内颗粒相互;运行过程中由于两侧床内压差不同使颗粒横向流动导致两侧床内颗粒浓度不同;在不进行主动调节,单侧床内颗粒浓度随时间的积累逐渐增大最后产生翻床现象;利用功率谱和小波分析揭示了颗粒压力脉动的低频特性。Based on gas-solid Euler-Euler two-fluid model, a simulation to the phenomenon of particle pressure fluctuation and bed overturn in larger particles dual-fluidized bed is conducted. The data obtained by using power spectrum density and wavelet is analyzed. The results show that the main factors of particle pressure fluctuation in dual-fluidized bed are bubbles formation and rupture and particles exchange. Because of the different of the pressure on both sides of the bed so that the particles lateral flow, leading to different particle concentrations on both sides of the bed.Without proactive regulating,unilateral bed particle concentration increase with the accumulation of time and produce the phenomenon of bed overturn lastly. The use of the power spectrum density and wavelet also reveals the microscopic characteristic of particles collision and broadband spectral characteristic of collision frequency and low-frequency characteristic of particle pressure fluctuation.

关 键 词：气固两相流动 颗粒压力脉动 翻床现象 数值模拟 双支腿流化床 

分 类 号：TK227[动力工程及工程热物理—动力机械及工程]