焦炭塔瞬态温度场的分析

Analysis of Transient Temperature Field in Coke Drums

由于循环的温度变化产生的严重温度梯度是导致焦炭塔出现鼓胀和开裂的主要原因之一.与以往文献的有限元分析不同,从二维热传导理论出发,获得了焦炭塔的轴向和径向二维瞬态温度场的解析解.所考虑的焦炭塔塔体为有限长,并采用迭代法模拟进油阶段和进水阶段中由于液面不断上升引起的动态边界条件.数值结果分析表明,该文理论模型能正确描述焦炭塔瞬态温度场的基本特征.同时,探讨了几何尺寸和冷却水升速对轴向温度梯度的影响.

One of the primary reasons leading to bulging and cracking in a coke drum is the severe temperature gradient due to cyclic temperature variation. Based on the two-dimensional heat conduction theory, the analytical solution of the transient temperature field in the coke drum was derived, which was different from the known FEM results. The length of the coke drum was considered finite, and the dynamic boundary conditions caused by fluid uninterrupted rising in oiling and watering stages were simulated by the iteration method. The numerical resuits show that the present theoretical model can accurately describe basic features of the transient temperature field in the coke drum. Effects of the geometry of the coke drum and the rising velocity of quench water on the axial temperature gradient are also discussed.