Influence of wire mesh electrodes on dielectric barrier discharge

A dielectric barrier discharge in a 2 mm air gap was studied. The experiments show that the mesh electrode and PET film really make the discharge looking homogeneous. The breakdown onset voltage in the case of a mesh electrode and PET film is 6.4 kV, considerably lower than 8 kV, the breakdown voltage in the usual case using two spherical electrodes. The field calculations show that even with this much lower voltage the gap field in the region very close to the PET film is enhanced to a value near the breakdown field in the usual case. It may be this field enhancement that initiates a corona discharge which provides seed electrons, leading to the breakdown of the whole air gap at a lower voltage. A lower voltage applied to the gap means a lower averaged field over the gap. Because the development of an electron avalanche is very sensitive to the electric field, a small decrease in the field will depress the avalanche significantly, preventing a homogeneous discharge from transiting to filament discharge. This may be the reason why a mesh electrode and PET film make the discharge look homogeneous.