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对两种不同入口尺寸的急速混合管状火焰燃烧器开展了丙烷富氧燃烧特性研究,着重从火焰结构、燃烧范围、燃烧模式等,分析了燃料与氧化剂切向入口尺寸分别为0.5/0.5 mm(燃烧器A)及0.25/0.5 mm(燃烧器B)的丙烷燃烧特性,并基于Chemkin计算分析了内在机制.结果表明:在氧气浓度β≤0.5时,两者均能获得均匀稳定的管状火焰,火焰特征和燃烧范围相近;对于燃烧器A,随着β增加至0.7,化学反应时间缩短,掺混效果不足以维持火焰稳定;燃烧器B入口尺寸较小,入口速度更大,掺混更充分,在β=0.7时火焰仍稳定,β=0.8时火焰不均匀但仍稳定.此外,β≥0.7时,随当量比增加,燃烧器A、B均在低当量比和化学计量当量比附近出现了声不稳定现象,管状火焰区随β增加不断缩小.“,”Rapidly mixed tubular flame burners of different inlet sizes were adopted to investigate the oxy-fuel combustion of propane.The variations of flame structure,flammable range,sound pressure and combustion mode were carried out on two burners with disparate inlet size 0.5/0.5(A) and 0.25/0.5(B).And the mechanisms were analyzed based on Chemkin.The results illustrated that when β ≤0.5,a uniform and stable tubular flame could be established within a similar range;In burner A,when increasingβ to 0.7,the flame became unstable in structure due to shorter reaction time;Burner B,with smaller inlet size,consequently larger inlet velocity and better mixing condition,sustained a stable tubular flame up to β=0.7.By further increasingβ to 0.8,the flame became non-uniform but still stable.Besides,whenβ ≥0.7,the sound pressure fluctuation in both burners arose at low equivalence ratio and stoichiometric equivalence ratio.Furthermore,tubular flame range shrunk withβ increasing.