空气预热器蓄热板硫酸氢铵动态积灰模型  

Dynamic ash deposition model of hydrogen sulfate in an air preheater

作　　者：雷健康 王浩楠 赵伶玲[1] LEI Jiankang;WANG Haonan;ZHAO Lingling(Key Laboratory of Energy Thermal Conversion and Control of Ministry of Education,Southeast University,Nanjing 210096,China)

机构地区：[1]东南大学能源热转换及其过程测控教育部重点实验室,江苏南京210096

出　　处：《热力发电》2020年第9期52-57,共6页Thermal Power Generation

摘　　要：为提升空气预热器(空预器)蓄热板硫酸氢铵(ABS)黏结性积灰的模拟精度,采用动网格技术和Fluent软件自定义编码(UDF)构建了可预测ABS黏结性积灰颗粒与蓄热板表面碰撞、黏附、生长及剥离的动态积灰模型,并对某600 MW机组回转式空预器的3种蓄热板型进行了数值模拟,分析了蓄热板积灰层、压力场分布和积灰强度的变化规律。结果表明:本文构建的动态积灰模型可描述灰垢外形生长过程及其导致的烟道压降变化;人字形波纹和弓形波纹蓄热板的结合可有效降低冷端ABS导致的黏结性积灰量,其黏结性积灰量仅为传统DU型板的50%;ABS黏结性积灰区的积灰强度为松散性积灰区的5倍及以上。该结论对脱硝机组空预器蓄热板改造及吹灰器吹扫具有一定的工程指导意义。In order to improve the simulation accuracy of ammonium bisulfate(ABS)ash accumulation in air preheater,dynamic model for predicting ABS cohesive ash depositions was established by dynamic mesh technology and UDF code in Fluent software.The model can describe the collision,adhesion,growth and peeling of ash particles on surface of the regenerative plate.Three types of regenerative plates of rotary air preheater in a 600 MW boiler is simulated to analyze the ash distribution,pressure distribution and ash strength distribution.The results show that,the established dynamic ash deposition model can describe the growth process of ash shape and the change of flue pressure drop caused by it.The combination of herringbone corrugated and arched corrugated regenerative plates can effectively reduce the amount of cohesive ash deposited by ABS in the low temperature section,which is only 50%of the ash deposition on conventional DU type plate.The ash accumulation strength of the ABS cohesive ash deposition area is 5 times or more of that of the loose ash area.This conclusion has a certain engineering guiding significance for air preheater regenerator retrofitting and soot blower purging.

关 键 词：回转式 空气预热器 蓄热板 硫酸氢铵 黏结性积灰 动态积灰模型 动网格 

分 类 号：TK224.9[动力工程及工程热物理—动力机械及工程]