大功率氧煤燃烧器内冷态流场试验研究

Experimental Studies on the Two-Phase Flow in a Large Power Oxygen-Coal Combustor

研究热风管中不同结构的氧煤枪出口下游冷态两相流场。提出高炉炼铁大功率氧煤燃烧器新型结构。用流场显示，热球风速仪，三孔探针和取样探针给出其中时均速度场、回流区大小、位置及颗粒浓度分布。冷态试验结果表明：大口径同轴射流渐扩式大功率氧煤燃烧器在加强氧煤混合，增长煤粉停留时间，强化枪体冷却。延长使用寿命上会有好的效果。为实现提高大喷煤量气化率的热态试验和结构优选提供了依据。

n the blowpipe the isothermal two-phase flow fields behind an oxygen-coal lance for various structures were investigated. A new structure of the large power oxygen-coal combustor used in the blast furnace was proposed- By using a hot-ball probe, a three-hole probe and a sampling probe, the time-averaged axial velocity fields, the size and position of recirculation zone, as well as the particle concentration distribution were measured. The results show that our large power oxygen-coal combustor characterized by coaxial tubes with an expanding exit in the inner tube is favorable to enhance the cooling of oxygen-coal lance and the mixing level between pulverized coal and oxygen, and to increase the coal-particle residence time and the service life of oxygen-coal lance. The results provide some basis for carrying the real combustion test and for optimum designing the combustor structure in the realization of high rates coal injection to the blast furnace.