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Filtration studies about the metal foam filters combined with electrostatic precipitation, which can be used as a new DPF device, have been performed. Filtration efficiency of the metal foam filter is significantly low because most particles are penetrated through the large filter-pores. However the efficiency was considerably improved by forming a high electric field on the filter surface. The pressure drop was not significantly increased by the particle deposition because the particles do not completely clog the filter pores.

In order to improve the predicting capability of KIVA-3V code for a diesel engine, various numerical models were reviewed. From the comparison of TAB, wave and χ - square distribution models for atomization of a liquid fuel jet, it was found that the wave model was most suitable for predicting a diesel spray because of proper breakup length. The high pressure evaporation model, which considered the air in a combustion chamber as a real gas, predicted earlier ignition about 0.7 °CA than the low pressure model. For the diesel ignition, the Hardenberg model predicted shorter ignition delay than the Shell model and measurements, and the Hardenberg model showed the spatially uniform ignition. For soot emission, the phenomenological models suggested by Foster, Belardini and Hiroyasu were studied. The Hiroyasu model could be used effectively for the prediction of soot emission although it did not provide detailed information on soot formation.

A Diesel Particulate Filter (DPF) is an effective technology for reducing Particulate Matter (PM) emitted from diesel engines. In modern light duty diesel engines, DPF is regenerated by the post-fuel-injection method. In this method, the fuel is injected into the combustion chamber during the expansion stroke to produce heat to burn out the PM trapped in the DPF. However, this method also causes several problems, such as complicated engine torque control and oil dilution by fuel. In this study, a rotating plasma burner was developed for DPF regeneration as an alternative to the postfuel-injection method. Since it is important to reduce the electric energy consumption for plasma generation, which is directly related with electric noise and system cost, several design factors, such as the boosting voltage of transformers, electrode gaps, and plasma frequency were evaluated. A transformer with a low boosting voltage is desirable to ensure low electric noise.