DPF滤芯装配的优化研究

Research on the Optimization of Filter Element Installation in DPF

滤芯是DPF内的重要功能实现单元,DPF内空间较小,滤芯位置的不同会影响滤芯前端的气体流动情况、颗粒物沉积特性及DPF的整体压降特性等。对DPF滤芯不同安装位置对于滤芯前端气体流动特性的影响进行了研究,利用CFD软件计算了滤芯在不同位置时滤芯入口端面上的轴向速度、湍动能等参数,使用均匀性指数衡量不同滤芯位置对气流分布的影响,结果表明:均匀性指数影响整体压降的变化,不同位置滤芯的均匀性指数相差约3%,相对应位置的压降相差约2.2%。

The filter element is an important functional unit of DPF,with small space in the DPF,the installation position of fil⁃ter element will affect the flow at the inlet of the filter,particulate deposition characteristics and the overall pressure drop.To study the influence of different installation positions of DPF filter on the fluid flow,the CFD software is used to calculate the axial velocity and turbulence kinetic energy at the inlet of filter element,the uniformity index is used to measure the effect of filter posi⁃tion on flow distribution.The results show that:the uniformity index increases along with the overall pressure drop decreases,the difference between the maximum and minimum values of uniformity index at different position is about 3%while the overall pres⁃sure drop is about 2.2%.