The effect of catalyst sizes on discharge power in dielectric barrier discharge reactor

Abstract

Dielectric Barrier Discharge (DBD) with catalyst can remove NOx effectively from diesel exhaust gas, the solid catalyst particles in the type of one section DBD reactor can play the role of barrier, lead to improve the discharge power effectively. The effect rule of the particle diameter which filled in the DBD reactor on the discharge power is studied by establishing mathematical model and testing in this paper. The results show that the discharge power first increase and decrease afterwards with the improving of material filler diameter, as well as the effect of particle diameter on the discharge power is more significant in pace with the input voltage rising. The gap enhances with particle diameter increases when the filler particle diameter is lager than the peak in the DBD reactor, under the same conditions, gap capacitance is less than solid particles capacitance, reducing the total capacitance decrease, so discharge power decreases with the particle diameter increases. When the filler particle diameter is less than the peak, the thickness of the equivalent capacitance of solid particles becomes smaller with the particle diameter decreases, susceptible to breakdown, the capacitance reducing, so discharge power falls with the particle diameter decreases. The discharge enhances with the input voltage increases, the effective area improving while the maximum effective discharge area is related to the particle diameter, so the effects of particle diameter on the discharge power is enhanced with the input voltage increases. The filler particle diameter has little effect on the total input power of the reactor because the total input energy is not only consumed for the system discharge, but also resulted heat the system. Theoretical model has the basically variation trend with experimental test results, the result provides the theoretical basis for selecting a suitable diameter of catalyst particles in catalytic reactions which assisted with DBD.