摘要
为探究非对称柴油机颗粒捕集器(diesel particulate filter,DPF)的孔道堵塞现象,采用计算流体动力学(computational fluid dynamics,CFD)–离散单元法(discrete element method,DEM)耦合计算与DPF可视化试验相结合的方法,研究了DPF内不同沉积形态积炭层的破碎及二次迁移对孔道堵塞特性的影响。结果表明:DPF孔道内碳烟颗粒的均匀或线性增加沉积形态,其积炭层的二次迁移最为活跃,积炭层极易运动至孔道末端形成大型端塞。对于碳烟颗粒的线性减少、凹型、凸型沉积形态,其积炭层的二次迁移会在孔道内形成多个小型堵塞段,其中凹型形态的堵塞段距DPF入口端的距离最近,而凸型形态的堵塞段积炭层分布率最高。均匀与线性增加形态的积炭层在孔道前、中段的分布较为轻薄,因此更易随气流运动至孔道末端形成端塞。线性减少、凹型、凸型形态的积炭层在孔道前、中段的分布较为厚重,因此更易过早脱离气流运动在孔道内形成中段堵塞。
To investigate the channel blockage phenomenon in an asymmetric diesel particulate filter(DPF),a combined approach using computational fluid dynamics(CFD)coupled with the discrete element method(DEM)and DPF visualization experiments was employed.The effects of the breakup and secondary migration of soot cakes with different deposition morphologies on the blockage characteristics within the DPF channels were studied.The results indicate that for the uniform or linearly increasing deposition morphology of soot particles,the secondary migration of the soot cake is the most active,making it prone to forming large terminal blockages at the end of the channels.In contrast,for linearly decreasing,concave and convex deposition morphologies,the secondary migration of the soot cake results in the formation of multiple small blockage segments within the channels.Among these,the concave morphology tends to have blockage segments which are the closest to the DPF inlet,while the convex morphology exhibits the highest density of blockage segments.The soot cake with uniform or linearly increasing morphologies are relatively thinly distributed in the front and middle sections of the channels,making them more likely to move with the airflow to the channel ends and form terminal blockages.The soot cake with linearly decreasing,concave,and convex morphologies are more thickly distributed in the front and middle sections,making them more prone to early detachment from the airflow,resulting in mid-channel blockages.
作者
张韦
房玉峰
孟丽苹
陈帅
陈朝辉
赵逸群
郭宥成
ZHANG Wei;FANG Yufeng;MENG Liping;CHEN Shuai;CHEN Zhaohui;ZHAO Yiqun;GUO Youcheng(Yunnan Key Laboratory of Internal Combustion Engine,Kunming University of Science and Technology,Kunming 650500,China;School of Architecture Engineering,Kunming Metallurgy College,Kunming 650300,China)
出处
《内燃机工程》
北大核心
2025年第5期87-99,共13页
Chinese Internal Combustion Engine Engineering
基金
国家自然科学基金重点项目(52166007、22362018)
云南省教育厅科学研究基金项目(2024J1369)
大学生创新创业计划项目(202310674063)。
