Reciprocating flow regeneration of soot filters

Particulate filter systems will most likely be required for compliance of diesel-powered vehicles and equipment to future emission legislation. The major issue with such systems is that their reliable and cost-effective regeneration (through oxidation of the collected soot particles) is not currently possible under all engine operating conditions without additional external thermal energy. In the present work we exploit the autothermal properties of the reverse flow reactor and study its application for the improvement of the regeneration process of diesel particulate filters. The reciprocating flow regeneration of soot filters is investigated with the aid of a mathematical model for the regeneration process, after the model has been assessed against conventional experimental regeneration data. The numerical results confirm the capability of the new technique to provide a clean filter where conventional regeneration fails. In this way the operating limits of current regeneration techniques (thermal or catalyst-assisted) can be extended substantially, and the stage is set for the construction of an industrial prototype. (C) 2000 by The Combustion Institute.