【摘要】 用DISA热线风速仪研究了氧枪射流中心轴线上和横截面上脉动速度、湍流强度以及自相关系数的变化规律。实验结果表明,在射流中心轴线上,脉动速度随着距喷嘴出口的距离增加而衰减,湍流强度在H/d_e≥20～25以后保持不变;在与射流中心轴线的半锥角为1°的圆锥面上,脉动速度为最大,在9.25°的圆锥面上湍流强度最大;在射流的横截面上,自相关系数为一常数。这些结果为探讨LD转炉和VOD等吹炼过程中氧气射流与熔池作用,以及氧枪的设计和操作提供了参考。更多还原

【Abstract】 Turbulent fluctuation velocity, turbulence intensity and autocorrelation coefficient on both cross sectional area and centerline of a supersonic free jet were studied by a DISA hot-wire anemometer. The experiments showed that along the jet axis the turbulent fluctuation velocity decays with the increase in distance from the exit of a nozzle, but the turbulence intensity remains almost constant after H/d₀≥20-25. The maximum turbulent fluctuation velocity lies at a circular cone-surface which meets the jet axis at an angle of β=1°, while the maximum turbulence intensity at an angle of β=9.25°.The autocorrelation coefficient is constant over a cross sectional area of the jet.From the above experimental results, some reference data have been provided for understanding the effects of a supersonic jet on a melt as well as for the design project and operation for an oxygen lance in LD converters and VOD processes.更多还原