Uneven Dielectric Barrier Discharge Reactors for Diesel Particulate Matter Removal

Uneven dielectric barrier discharge (DBD) reactors driven by positive–negative pulse plasma discharges were investigated for particulate matter (PM) removal from a diesel engine. Two kinds of uneven alumina plates and three kinds of uneven stainless steel plates were used to assemble six kinds of uneven DBD reactors of discharge gaps 0.4–1.0 mm. The experimental results show that PM from diesel engines can be removed using the uneven DBD reactors. The maximum PM removal was 67% at 300 W energy injections using the DBD reactor of 0.4 mm gap distance. PM removal increased with decreasing gap distance. The energy efficiency using the uneven DBD reactor of a shorter gap distance was higher than that using the uneven DBD reactor of a longer gap distance as the uneven DBD reactor of a shorter gap distance has a higher PM deposition rate. The energy efficiency was typically in a range of 3–10.6 g/kWh at an energy density of 2–16 J/L. A comparison of this study with reports given by other research groups is given.