Abstract: A oxygen lance jet examination system with coherent jet oxygen lance Laval nozzle containing central main hole and 16 auxiliary holes is used to study the oxygen jet central velocity weakening rule, measure the coherent jet produced with accompanying flow of helium at ambient temperature to replace shielding gas burning at high temperature and the coherent jet simulated by flowing air in main hole and flowing shielding gas produced from oxygen and propane in both side auxiliary holes at high temperature. Results show that the characteristics of coherent jet are better than that of traditional jet, at ambient temperature with increasing the pressure of entrance helium the axial weakening of central jet is slowing to get longer length of supersonic jet region than that of traditional jet; at high temperature the length of circle flame can be changed by adjusting burning gas and oxygen flow rate while according to melting real condition it is available to change the length of main jet and meet the requirement of melting process.

摘要： 利用带有中心主孔的Laval喷管和16个副孔的聚合射流氧枪喷头的氧枪射流检测系统研究氧枪射流中心速度的衰减规律,测试常温氦气代替高温燃烧的保护气体作为伴流而产生的聚合射流,以及高温以主孔通空气,两副孔分别通入氧气和丙烷来产生保护气体模拟的聚合射流。结果表明,聚合射流特性优于传统射流特性,常温下随氦气入口压力增加,中心射流的轴向衰减变缓,获得比传统超音速射流更长的超声速区域;高温下通过调节燃气和氧气流量可改变环状火焰长度,同时可以根据生产实际情况变化主射流长度,满足冶炼工艺要求。