退火钢卷辐射换热及对流换热的讨论

主要研究罩式炉退火钢卷在退火过程中，对流热流及辐射热流的变化情况及其影响因素，由此得到退火过程的不同阶段对流热和辐射热的大小比较，以判断在计算过程中，忽略辐射热流是否合理。计算得出，到退火加热中期，钢卷通过对流获得总热量是通过辐射获得的总热量的35倍，到保温中期，这两个量仅相差9倍，且退火保温时间越长，二者差距越小。

Discussion of convection heat transfer and radiation heat transfer of annealing coil

The main subject is about convection heat transfer and radiation heat transfer of steel coil in the HPH (High Performance hydrogen) bell-type annealing furnace .It depicts the quantity changes of the two heat transfer in the course of annealing, and the factors resulting in those changes .According to the comparison of the two heat transfer, the feasibility to neglect the radiation heat transfer in the mathematical model calculation is discussed. It reveals that in the middle of heating process, the heat quantity that obtained through convection heat transfer of steel coil is 35 times as much as the heat quantity obtained from radiation heat transfer, However, in the middle of heat soak ,the ratio of the two heat quantity is only 9 times, and the gap between them decreases as the increase of the time of heat preservation.