焦炭塔工作过程温度场仿真分析

Temperature Field Simulation of the Working Process of Coke Drum

利用ANSYS有限元分析软件对焦炭塔一个循环工作过程进行了瞬态温度场模拟。以塔底、塔顶进出口介质随时间变化检测温度沿高度方向线性拟合所得的温度作为热分析边界条件,换热边界温度为时间和高度的复合函数,实现了进油和水冷阶段的动态换热内边界模拟。应用生死单元技术实现焦炭塔进油生焦过程模拟。分析表明,预热及蒸汽冷却阶段焦炭塔各处温度变化均匀。进油生焦阶段由于油气混合相不断攀升,导致与壁面接触时壁面温度迅速增高。水冷阶段短时间内温度变化幅度大,温度变化速率高,热梯度变化规律复杂。

Using the ANSYS finite element analysis software simulated the temperature field of the coke drum′s working process.The data of top and bottom field surveying temperature linear fitted along the highly direction acted as thermal analysis boundary conditions,as the boundary temperature is a composite function about time and height,dynamic thermal boundary problem during the coke-forming and water-cooling stages was solved.Element birth and death technology was used for simulating the coke-forming process.Analysis showed that coke drum′s temperature rises steadily during preheat and steam-cooling stages.In coke-forming stage,mixed-phase interface gradually rise up.When the drum wall contact with the interface its temperature will rising dramatically.Temperature change rate is high and the trend of thermal gradient variation is complex during water-cooling stage.