用于燃煤电厂的低温省煤器前烟道流动及磨损特性

Flow and wear characteristics in front flue of low-temperature economizer used in coal-fired power plant

以低温省煤器及其管道为研究对象,采用数值模拟方法,对低温省煤器及其管道流动及磨损特性进行分析,采用添加导流板的方式对流场进行优化以降低磨损量。低温省煤器前方圆节的布置导致流场紊乱,低温省煤器入口截面速度分布均匀性较差,管束磨损区域与高速区相对应,冲蚀磨损主要集中在中心区域,第一排管束迎风区磨损量最大,后排管束磨损量依次降低;对方圆节内置导流板进行优化后,低温省煤器前流场速度标准偏差由34.9降低至15.2,均匀性提高,管束的最大冲蚀磨损量降低两个数量级,磨损程度大幅度降低,保障了低温省煤器的安全经济运行,为低温省煤器及其管道的优化设计及运行提供了理论参考与数据支持。

Regarding the low-temperature economizer and its tubes as the research object,the flow and wear characteristics were analyzed by numerical simulation,and the flow field was optimized by adding diversion plate to reduce wear.The study showed that the flow field was disordered due to the arrangement of the square section in front of the low-temperature economizer,and the velocity distribution uniformity of the inlet section was poor.The wear area of the tube was corresponding to the high-speed zone,and the erosion wear was mainly concentrated in the central area.In the windward area,the wear of the first-row tube bundle was the largest,and the back row tube bundle decreased successively.The flow field Cv in front of the low-temperature economizer was reduced from 34.9 to 15.2 by optimizing the guide plate in the circular to rectangular air duct,and the uniformity was improved.After the improvement,the maximum erosion wear of tube bundle was reduced by two orders of magnitude,and the average wear degree was greatly reduced,which ensured the safe and economical operation of the low-temperature economizer and provided theoretical reference and data support for its optimal design and operation.