火电机组烟道积灰特性及防治方法的数值模拟研究  

Numerical Simulation Study on Characteristics and Prevention Methods of Ash Deposition in Thermal Power Units Flue

作　　者：闫优洋 陈冬林[1] 杨展 王帅浩 YAN Youyang;CHEN Donglin;YANG Zhan;WANG Shuaihao(School of Energy and Power Engineering,Changsha University of Science and Technology,Changsha 410114,China)

机构地区：[1]长沙理工大学能源与动力工程学院,湖南长沙410114

出　　处：《湖南电力》2025年第2期63-68,共6页Hunan Electric Power

摘　　要：针对火电机组深度调峰引发的烟道内积灰问题,通过构建烟道结构几何模型及内部流动的数学模型,基于Fluent的数值模拟方法,研究机组不同负荷工况下烟道内飞灰沉积特性及其颗粒分布特性,并基于工程实践经验提出烟道防积灰方法——烟道内加装导流板和高速射流喷管。模拟研究表明:当机组负荷低于80%时烟道内飞灰开始沉积,而当负荷低于40%时烟道内飞灰大量沉积;不同结构烟道的飞灰颗粒沉积量呈现出以下规律:T型烟道>直角弯头>水平烟道>渐变烟道,且所沉积的飞灰颗粒90%以上直径大于34μm;与现有烟道相比,加装导流板或射流喷管后的烟道在机组低至40%负荷运行时飞灰沉积量可减少29.16%~58.62%。In order to solve the problem of ash deposition in the flue caused by deep peak loading regulation of thermal power units,based on the numerical simulation method of Fluent,the characteristics of fly ash deposition and particle distribution in the flue under different load conditions of thermal power units are studied by constructing a geometric model of the flue structure and a mathematical model of its internal flow.A method to prevent ash deposition in the flue is put forward based on the practical experience of engineering,which is to install a baffle and a high-speed jet nozzle in the flue.The simulation results show that fly ash begins to deposit in the flue when the load of the unit is lower than 80%,and a large number of fly ash deposits in the flue when the load is lower than 40%.The pattern of fly ash particle deposition in different flue structures is as follows:T-shaped flue>right-angle elbow>horizontal flue>gradual flue.And more than 90%of the deposited fly ash particles are larger than 34μm in diameter.Compared with the existing flue,the flue equipped with the baffle or jet nozzle can reduce the fly ash deposition by 29.16%~58.62%when the unit is operating at 40%of the rated load.

关 键 词：烟道 积灰特性 数值模拟 积灰防治 

分 类 号：TK227.3[动力工程及工程热物理—动力机械及工程]