蓄热式燃烧器优化设计数值模拟

借助于数值模拟的方法,完成了蓄热烧嘴的优化设计,分析了蓄热式烧嘴关键结构——空气和煤气喷口距离及入射角度对燃烧流场、温度场和浓度场的影响,结果表明:(1)烧嘴喷口距离在15D～20D间调整和角度在3°～9°间改变对炉内整体温度水平和温差大小结果影响不大,燃烧高温区主要集中在炉膛的中部,温度梯度较小,温度分布很均匀,炉膛中心区域内温度差在100℃以内。(2)烧嘴喷口间距小时,喷口角度不宜过大,否则会出现燃烧不完全现象。当烧嘴喷口间距过大时,喷口角度不能过大也不能过小。综合分析确定烧嘴结构在18D、5°组合状态下燃烧效果最优,性能最稳定。最后通过实验证明实验烧嘴炉内温度场和浓度场分布规律与计算结果一致。

Numerical Simulation on Optimum Design of Regenerative Burner

The optimum design of regenerative burner was completed by using methods of numerical simulation. The influences of the key structure of the nozzle, which including the distance and the entry angle of gas nozzle and air nozzle, on flow field, temperature field and concentration field during the combustion were analyzed. The results indicated that： （1） The change of the distance between air nozzle and gas nozzle in 15D-20D and the angle of nozzle in 3°-9° has little influence on temperature, and the high temperature zone mainly concentrated in the middle of the furnace, the temperature field was uniform, the temperature difference was less than 100℃. （2） The matching of nozzle distance and nozzle angle was important, and the inappropriate design would cause incomplete combustion. After comprehensive analysis it was confirmed that 18D and 5° was the optimal combination about the nozzle structure. Finally, the simulation result was confirmed to be consistent with the experimental data.