气体回流区分级着火试验研究

TEST INVESTIGATION ON STEPPED FIRE IN RECIRCULATION ZONE FOR GAS

就回流区分级着火燃烧方式在气体燃料燃烧上的应用进行了一系列冷热态模拟试验和工业试验研究．比较了直流、钝体和开缝钝体喷口的出口速度、温度分布，以及在不同气体燃料热值时的稳焰能力。试验表明，开缝钝体喷口中缝小股射流进入喷口后低速回流区能稳定着火，进一步点燃主流，有效地形成回流区分级着火；开维钝体喷口的稳焰能力最强，特别适合低热值煤气燃烧。在大容量锅炉上进行了低热值高炉煤气燃烧的改造性工业试验，试验证明，开缝钝体燃烧器强化了低热值煤气的燃烧，有效地解决了锅炉煤气段燃烧强度不足以至锅炉尾部超温问题。

A series of cold, hot and industrial test for gas combustion on principle of stepped ignition in recirculation zone have been carried out. Three kinds of burners, straight jet, bluffbody and slitting bluff-body types, have been compared for their flow velocity temperature behind and fire stability with poor or rich gas. Test show that using slitting bluff-body burner a small fuel flow entering the recirculation zone can immediatly fire and then ignite the main flow having effectively stepped combustion. It is proved that slitting blumbody burner can stress combustion of poor gas fuel and therfore avoid uncomplete combustion in gas section and over-temperature at the tail of the boiler.