改进的动力学模型对DPF热再生过程的影响  

Influence of Revised Kinetics Model on DPF’s Thermal Regeneration

作　　者：唐君实[1] 宋蔷[1] 徐小波[1] 李水清[1] 姚强[1] 

机构地区：[1]清华大学热科学与动力工程教育部重点实验室,北京100084

出　　处：《燃烧科学与技术》2010年第2期111-117,共7页Journal of Combustion Science and Technology

基　　金：国家重点基础研究发展计划(973)资助项目(2002CB211600)

摘　　要：针对柴油机颗粒捕集器的再生过程建立了数学模型.考虑到颗粒在反应过程中比表面积变化对反应速率的影响,通过热重分析仪上的等温氧化实验和程序升温实验,求得了柴油机碳烟颗粒氧化的比表面积变化函数和动力学参数,建立了碳烟氧化的反应速率方程.通过数值模拟将本模型与传统的Bisset-Konstandopoulos模型(B-K模型)进行对比,结果表明,由于采用了更符合碳烟氧化过程的反应方程,本模型计算得到的再生时间短、最大壁面温度高、最大壁面温度梯度大,而B-K模型计算结果高估了再生时间,低估了最大壁面温度和最大壁面温度梯度,不利于再生过程的安全性和经济性分析.Based on change of specific surface area of soot determined by TGA isothermal oxidation test and kinetic parameters of soot oxidation determined by temperature programmed oxidation test, an advanced model describing the thermal regeneration process in monolith was developed, in which a new formula of soot oxidation was incorporated. Numerical simulation of DPF regeneration process was developed to compare this advanced model with traditional B-K model. The comparison results showed that B-K model overestimated necessary regeneration time, and underestimated maximum wall temperature and maximum wall temperature gradient. The difference of numerical results by the two models was revealed by a soot oxidation equation. The advanced model is helpful for optimizing DPF regeneration process and in achieving economy and safety of the process.

关 键 词：柴油机颗粒捕集器 热再生 碳烟 氧化 温度 

分 类 号：TK421.5[动力工程及工程热物理—动力机械及工程]