To study characteristics of surface discharge effect in DBD

two sets of comparative experiments were con-ducted on plate-plate and multi-needle-plate electrode structures and microcavity-plate and thin plate-thin plate elec-trode structures. U-Q Lissajous figures were employed to analyze the air-gap voltage and charge transport in the firstset of experiment

and the result showed that the transferred charge of the multi-needle-plate electrode structure wasabout 1.5 times that of the plate-plate structure under the same power consumption. The second set of experiment ver-ified the above result

that is

the surface discharge effect of the microcavity produced more transferred charge.Then

reduced electric field was adopted to analyze the variation of average electron energy and the difference of mo-lecular vibration temperature

and the surface discharge effect of the needle electrode corona on transfer of chargeand energy was discussed. It was revealed that

in the non-uniform electric field of DBD

the local reduced electricfield of the electrode tip with small radius of curvature was up to 750 Td

but the reduced electric fields in most of theair gaps were far lower than that of the plate-plate structure. Therefore

the average electron energy around the elec-trode tip was about 13 eV

which facilitates collision and ionization of the electrons in air and production of a largeamount of charge. However

in this case

the temperature of molecular vibration was lower

and the excited particlesgenerated in the discharge process were less than that generated by the plate-plate structure.