Modeling thermal regeneration of wall-flow diesel particulate traps

Stricter emission control legislation for diesel use has been increasing interest in highly efficient wall-flow particulate filters. The mathematical modeling of the filter regeneration process is indispensable in developing reliable and durable trap systems for various applications. Although modeling of wall-flow filters has been investigated extensively, significant problems still exist in the correlation of modeling results with measurements. This article describes an improved modeling and model tuning approach. A classical zero-dimensional regeneration model, modified to account for incomplete soot oxidation effects, is discussed, and existing and novel methods of estimating trap lending, crucial in all modeling applications, are compared. The design of a model tuning approach based on full-scale experiments is highlighted with examples of model predictions during trap failure that show capabilities of supporting the design of trap protection techniques. Applications to regeneration rate control, filter sizing and the development of on-board diagnostics are demonstrated with examples. Dimensional analysis is used for the concise quantitative evaluation of the parameters affecting the evolution of the regeneration process.