Modelling of DPF regeneration using microwave energy

Abstract

FEM based models in COMSOL multiphysics have been used to simulate regeneration of diesel particulate filter following the layout of an existing microwave cavity. The study utilized the physics packages in the software to model the electric field and thermal profiles of the microwave cavity and DPF. This was used to establish dimensions for microwave cavity and DPF. Further it was possible to integrate the heating properties of the Silicon Carbide used in the DPF substrate. The electric field and thermal profiles of the microwave cavity, as well as the DPF were investigated for the established dimensions and simulated results were compared with experiments. In the experiment, we deployed microwave power generated by a 2.45GHz magnetron into the existing microwave cavity to regenerate DPF. The results of the experiments showed the thermal profiles during DPF regeneration to be in agreement with the profiles from the simulated results. The scheme was further used to improve the design of the cavity for better energy utilization and DPF regeneration efficiency. Electric field and thermal profiles of the microwave cavity were established for various dimensions of microwave cavity for a given DPF size and the results were investigated. It was found that cylindrical cavity (diameter of 153mm and length of 533mm) gives the optimal dimensions for the regeneration of a commercial DPF (143mm (diameter) x 183mm (length) viewed in terms of near homogeneous electric field distribution.