A numerical investigation of the diesel particle filter regeneration process under temperature pulse conditions

A one-dimensional transient diesel particle filter (DPF) model is applied to study DPF regeneration performance. Numerical simulations are performed to predict the effects of various factors influencing regeneration performance under temperature pulse conditions, and the regeneration performances of three typical DPFs are compared and analyzed. Numerical results indicate that the thermal conductivity characteristics of DPF configurations can greatly affect soot oxidation, which in turn influences the regeneration process. The transition points of the regeneration flow rate indicate a balance between its promotion of the regeneration process and retardation owing to cooling effects. The sensitive ranges of soot loading, oxygen concentration, and inlet temperature are observed to provide a reference for controlling DPF regeneration. The multi-step exhaust condition is employed to control DPF regeneration. It was found that a transient increase in the flow rate is more effective at reducing the peak temperature and peak temperature gradient than a transient decrease of oxygen concentration.