加热炉三维段法动态数学模型在待轧中的应用

Application of Three-Dimensional Zone Method Dynamic Mathematic Model to Rolling Delay on Reheating Furnace

采用段法计算炉内辐射换热,在能量平衡的基础上建立了加热炉三维段法数学模型.给出了以稳态模型为基础的动态数学模型计算方法,并应用于加热炉待轧过程分析.多种不同待轧情况下的模拟结果表明:待轧的发生将对炉内传热过程产生较长时间的影响,待轧发生时应采用灵活的供热制度.具体来说,当发生较短时间事故待轧后可以较大幅度地降低燃料的供给,并可在待轧结束后一段时间内保持;而对较长时间的计划待轧,可在待轧之前适当时刻开始降低燃料供给量,并在待轧结束前开始逐步恢复燃料供给量.

A 3-D zone method mathematic model of reheating furnace was established based on energy balance to calculate the radiative heat transfer in a reheating furnace.The computational method of a dynamic mathematic model was given based on the steady-state model and applied in reheating furnace for rolling delay process analysis.The simulation results showed that the influence of rolling delay on the heat transfer process last for a long time.The flexible heating strategy should be adopted once the delay occurs.Specifically,fuel supply should be relatively substantially reduced and keep in a period of time after delay for the short time delay.For long delay,fuel supply should start to be reduced in an appropriate moment before delay,and began to gradually restore to the original quantity after delay.