不同喷嘴直径对加热炉燃烧器燃烧过程的影响

选用FLUENT软件,利用数值模拟的方法对加热炉燃烧器内烟气速度分布和温度分布做了详细研究,并考察了不同喷嘴直径对燃烧过程的影响情况。研究结果表明,喷嘴直径越小,速度峰值越大,射流的影响区域越大。这加剧了燃料与空气的混合,加快了燃烧速率,使燃烧在较短的区域内完成,且燃烧的火焰逐渐变短、变窄。随着喷嘴直径的增大,出口未完全燃烧的燃料逐渐增多,燃烧损失的热量越多,燃烧效率有所降低。但同时,随着喷嘴直径的增大,火焰高温区增大,提高了辐射传热效率。

Effect of Different Diameter of Nozzle on the Gas Combustion in the Combustor

Numerical simulation of combustion based on FLUENT in combustor with different diameter of nozzle was carried out.The simulated results showed that fuel velocity on the outlet of the nozzle and its peak value became larger with less diameter.The larger flow field affected by nozzle flow,the larger the mix and combustion rate between fuel and air.Then the flame became shorter and narrower.With the increase of nozzle diameter,incomplete combustion of fuel on outlet increased gradually,then the heat loss increased.It leads to reduced of combustion efficiency.However,with the increase of nozzle diameter,the high temperature field is increasing and then the efficiency of heat transfer is increasing.