“常化炉后快冷”控冷技术研究

Controlled cooling technology of accelerated cooling after normalizing furnace

"常化炉后快冷"控冷技术是实现"常化炉后快冷"的关键,本文重点介绍气雾冷却控制、高密集管流冷却控制的换热系数计算和考虑相变潜热影响的冷却温度计算,指出当分散相液滴占连续相空气的体积分数>10%～12%时,应采用混合对流换热模型;当分散相液滴占连续相空气的体积分数<10%～12%时,应采用离散相颗粒蒸发沸腾模型;用反传热法可很好获取现场的实际换热系数;要准确对钢板进行冷却控制,相变潜热的影响是不可忽略的。

It is key that cooling control technology of ＂Accelerated Cooling after Normalizing Furnace＂.For achieving ＂ Accelerated Cooling after Normalizing Furnace＂,the calculating heat transfer coefficients of air-water spraying cooling control and high-density pipe flow cooling control were described in this paper,and the influence of phase transformation latent heat during cooling was included in order to calculate cooling steel plate temperature,that was special explanation in the paper.The blending convective heat transfer model is used if the disperse phase＇s volume fraction is higher than 10%-12% of the sequence one;the disperse phase evaporation and boiling model is used,if the disperse phase＇s volume fraction is lower than 10%-20% of the sequence one;the practical heat transfer coefficient is achieved better by use of inverse heat conduction method;the influence of phase change latent heat must be included for accurate steel plate cooling control.