异距贴壁风喷口布置方案的数值模拟

doi:10.16085/j.issn.1000-6613.2017-2034

摘要/Abstract

摘要： 为了消除某600MW前后墙旋流对冲锅炉侧墙水冷壁出现的高温腐蚀现象，在前后墙开3层对冲贴壁风喷口，借助Fluent软件模拟计算了原始运行工况以及不同贴壁风工况下的炉内燃烧，并着重分析了侧墙近壁区内还原性气体（CO）浓度的分布情况；结果表明，数值模拟的结果比较符合炉膛实际的运行情况，不同贴壁风喷口类型的防腐效果并没有显示出太大差异；受上升烟气的携带作用，贴壁风喷口的布置方式对贴壁风的防腐效果影响很大；采用异距式贴壁风喷口的布置方式并结合贴壁风射流补氧特性，在贴壁风率消耗不到4%的前提下，就使侧墙近壁区的还原性气氛浓度达到较低水平，说明在合适的喷口布置以及速差组合的基础上，前后墙贴壁风布置方式可以有效地抑制侧墙水冷壁高温腐蚀。

关键词: 旋流对冲锅炉, 高温腐蚀, 异距喷口布置方案, 数值模拟

Abstract: In order to eliminate the high temperature corrosion of the side water-cooled wall in a 600 MW front and rear wall swirl-opposed firing boiler,three layers of opposed near-wall air nozzle were punched in the front and rear walls. The boiler combustion of original condition and near-wall air condition with different nozzle arrangement schemes was simulated by use of Fluent. The distribution of reductive atmosphere of near-wall region was emphatically focused on. The results showed that the simulation results agreed with the actual operation condition of boiler and the anti-corrosion performance of different nozzle patterns was limited. Due to the push of rising flue gases from the bottom,the nozzle arrangement had a great influence on the effect on anti-corrosion. In addition,by adjusting the position of nozzle and combining the nozzle flow characteristics,the coverage of reductive atmosphere in the near-wall region maintained at a low level while the ratio of near-wall air was less than 4%,indicating that the front and rear wall arrangement scheme can effectively restrain the high temperature corrosion of the side water-cooled wall on the basis of the combination of appropriate nozzle positions and nozzle flow velocity.

Key words: swirl opposed boiler, high temperature corrosion, scheme with different jet distances, numerical simulation

中图分类号:

TQ050.9

孟凡冉, 高畅, 金保昇, 张勇. 异距贴壁风喷口布置方案的数值模拟[J]. 化工进展, 2017, 36(09): 3237-3242.

MENG Fanran, GAO Chang, JIN Baosheng, ZHANG Yong. Numerical simulation of near-wall air scheme combined with different jet position[J]. Chemical Industry and Engineering Progress, 2017, 36(09): 3237-3242.

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