Numerical Simulation Model for the Regeneration Process of a Wall-Flow Monolith Diesel Particulate Filter

Regeneration experiments were carried out for the establishment of a particulate combustion model. Distributions of the filter temperature and gas temperature, the concentration of the oxygen in the filter, and combustion products were simultaneously measurd.

Numerical simulations were performed by two steps. As the first step, a quasi one-dimensional simulation model was applied to the estimation of propagation characteristics of the particulate combustion, such as flame velocities, and the filter temperature change with time. Air velocity and heat capacity of the filter were found to be important factors for the combustion propagation. As the second step, a two-dimensional axisymmetric simulation program for the regenerative combustion was developed and coupled with a FEM stress analysis program “MARC”. The axisymmetric simulation program coupled with “MARC” was applied to the analyses of the unburned phenomenon in the filter circumference and the filter crack caused by thermal stress. It was confirmed that the air velocity distribution, heat capacity and circumferential heat insulation were important factors for avoiding the generation of an unburned region and filter crack.