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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”.

Periodic regeneration of the diesel particulate trap is essential to maintain the collection efficiency and exhaust gas hack pressure at acceptable levels. The objectives of this study are to describe the phenomenology of ceramic foam filter regeneration process and to present its mathematical model. Further simulation study is carried out to estimate the effects of various factors including fuel additive on the ignition and the filter bed temperature and to investigate conditions of excessive temperature which could result in filter destruction. The model is based on the assumption that the regeneration process is composed of two steps. The first step is the additional heat supply from the external energy source, and the second step is the spontaneous combustion propagation. The results from the analytical model agreed very well with the experimental results.