| Regeneration of the monolith is the great difficulty in design of Diesel Particulate Filter (DPF) whose domestic research is at the just beginning and the recent basic resorts are experimental methods. But it is hard to get the instant internal data and to analyze influences caused by interactional factors in DPF via experimental testing when the diesel works. So we have to employ numerical simulation to get the law of regeneration process.Flow analysis in filter is a vital aspect. Since the flow distribution determines the convective heat transfer, then decides the temperature field in the filter, and eventually impacts the regeneration. An exhaust flow model of DPF, based on the terms of porous medium, is requisite to display the influences on flow induced by filter's configuration.This paper focuses the simulation research on regeneration process of DPF, which is nearly a piece of white paper in china presently. The whole simulation research is established by firstly analyzing the heated characteristics of clean wall-flow filters, then composing a mathematical model of regeneration process based on heating up and combustion theory, so we can obtain the three-dimensional temperature field and temperature gradient of the inner filters by numerical calculation. The results had good agreement with experimental data, which proved the accuracy of the model. In order to study the regeneration mechanism of DPF in detail, we still need a mathematical model of the channel unit, which present temperature field and the soot reaction rate of the channel. Finally, it points out the influences of various factors to the regeneration process by computing the numerical solution of model under different boundary conditions and geometry parameters, such as the initial temperature, the gas flow rate, the oxygen concentration, the sediment quantity and the wall thickness of the filters, and so on. In this way, the paper provides theoretical guidance for optimization design of the DPF.
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