特厚钢板阵列射流淬火的表面换热

采用特厚钢板专用辊式射流淬火试验装置和多通道钢板温度记录仪,测试出射流速度3.39~26.8 m·s-1、雷诺数12808~117340、水流密度978.7~6751.5 L·(m2·min)-1条件下,84 mm厚钢板淬火冷却曲线;进而基于反传热修正方法计算高温钢板淬火过程壁面温度和热流密度,描绘出沸腾曲线,分析多束圆孔阵列射流对特厚钢板淬火表面换热的影响.结果表明:射流速度、水流密度等参数影响钢板表面射流滞止区和平行流区换热机制,进而影响最大热流密度分布.射流速度较低时,壁面平行流区观察到混合换热和"热流密度肩"现象;随射流速度增大,膜沸腾换热机制消失,最大热流密度移至较低壁面过热度处.相关研究将对特厚钢板淬火过程温度场计算和组织性能调控提供有益的帮助.

Surface heat transfer of jet array impingement quenching for ultra-heavy plate

Using the ultra-heavy-plate jet-impingement quenching test device and the multi-channel temperature recorder, 84 mm large section plates quenching temperature drop curve was experimentally investigated under the condition of jet velocities ranging from 3. 39 to 26. 8 m·s-1 , Reynolds number from 12808 to 117340 and jet densities ranging from 978. 7 to 6751. 5 L·( m2·min) -1 . Then, wall heat flux, heat transfer coefficient and boiling curve were calculated with inverse heat transfer modified method. The results indi-cate that both jet velocity and jet density influence the plate surface heat transfer mechanism and the distribution of the maximum heat flux. When jet velocity is low, a mixed heat transfer and"heat flux shoulder" phenomenon can be observed in wall parallel flow zone. With increased jet velocity, the film boiling heat transfer mechanism disappears and the maximum heat flux changes to the low-wall su-perheat position. These research results benefit the calculation of the temperature field and the control of structure property during ul-tra-heavy plate quenching.