二次风反切对大容量切向燃烧锅炉烟气偏差影响的数值研究  

NUMERICAL STUDY ON THE EFFECT OF REVERSE SWIRL OF SECONDARY AIR ON FLUE GAS IMBALANCE IN LARGE TANGENTIALLY FIRED BOILER

作　　者：李彦鹏[1] 张强[1] 顾璠[1] 徐益谦[1] 

机构地区：[1]东南大学热能工程研究所,江苏南京210096

出　　处：《中国电机工程学报》2001年第9期33-37,共5页Proceedings of the CSEE

基　　金：国家重点基础研究专项基金资助项目 (G19990 2 2 2 0 9)~~

摘　　要：在发展一个三维计算程序的基础上研究了二次风反切对大容量切向燃烧锅炉烟气偏差的影响。数值模型应用在一个不同二次风反切工况下的 6 0 0MW切向燃烧炉。模型采用空度方法以较好地模拟复杂的屏式过热器结构 ,采用修正的非均分QUICK格式以有效减小伪扩散的影响 ,采用标准k ε模型来处理湍流。计算结果与试验数据吻合较好。模拟结果表明 ,烟气偏差成因于炉膛出口的残余旋转 ;二次风反切在一定程度上能有效地削弱炉膛出口的残余旋转 ,从而降低水平烟道的烟温偏差 ;但是过量反切可能会破坏炉内流场 ,并可能加大烟温偏差。因此必须优化反切角度与反切动量流率。该文认为合理的反切方式应该是无量纲准则数XJ为 1左右时的配风工况。This paper describes a three dimensional computer simulation developed to study the effects of the reverse swirl of secondary air on flue gas imbalance in tangentially fired boiler. The model was applied to a 600MW tangentially fired boiler under different operating conditions of reverse swirl of secondary air. The main characteristics of the current model are the use of the Porosity method to simulate the complex platen superheaters correctly, the improved non uniform QUICK scheme to reduce the pseudo diffusion effectively, and the standard k ε model for turbulence treatment. The numerical results agree well with the experimental data. Results show that flue gas imbalance results from the residual swirl at furnace exit. The reverse swirl of the secondary air can effectively weaken residual swirl at furnace and then decrease flue gas imbalance in horizontal gas pass to a certain extent. But the excessive reverse swirl air might deteriorate the flow field in furnace, and might increase flue gas imbalance. So it is necessary to optimize the momentum and the direction of reverse swirl air. The paper suggests that it should be the optimum operating condition when the dimensionless number XJ is nearly equal to 1.

关 键 词：烟气偏差 二次风反切 切向燃烧 数值模拟 锅炉 电厂 

分 类 号：TK224.1[动力工程及工程热物理—动力机械及工程] TM621.2[电气工程—电力系统及自动化]