Wall flow filters are used for exhaust aftertreatment in passenger cars and commercial vehicles in order to comply with the legal requirements regarding the emitted particulate mass. The particles to be separated are primarily carbon-based components that are formed in the engine compartment due to incomplete combustion. With increasing operating time, the backpressure behaviour of the diesel particulate filter (DPF) increases due to the high mass of separated particles. For optimum operating performance, the filter must be regularly regenerated actively and/or passively. As a result of the regeneration process diesel ash remains in the filter as a cumulative regeneration residue. This has a particular influence on the separation and backpressure behaviour of the DPF due to different deposition pattern.

The focus of this research project is to describe the storage and rearrangement of the diesel ash within the individual DPF channels and to develop an understanding of the processes inside the filter...