Study On Two Square Superlattice Patterns With Surface Discharge In Dielectric Barrier Discharge

In this work,the discharge sequence and the formation mechanism of two kinds of square super-lattice patterns with surface discharge(a dot-line square super-lattice pattern with surface discharge,a square super-lattice pattern by interaction of surface discharge)were investigated in the dielectric barrier discharge system.In the above pattern,they have a high symmetry of macroscopic structure,and the microscopic formation mechanism and microscopic composition cannot be observed with the naked eye.Therefore,the above-mentioned pattern is studied by ICCD,and the relationship between the surface discharge and the volume discharge is further studied in this work.It is shown that the presence of surface discharge can promote the generation of volume discharge.At the same time,the interaction between the surface discharge and the surface discharge is further studied.It is found that when the applied voltage is high enough,a strong repulsion have between each other of the surface discharges generated in the dielectric barrier discharge,which in turn promotes a kind of the emergence of a new pattern.Firstly,we report a dot-line square super-lattice pattern with surface discharge(DLSSPSD)in a dielectric barrier discharge system and show for the first time that the surface discharge can promote the formation of volume discharge(VD).The pattern consists of three different discharge morphologies,namely,bright spots,dim spots,and bright lines.The spatiotemporal dynamics of the DLSSPSD are studied using an intensified charge-coupled device camera,a photomultiplier,and a high-speed video camera.The results show that the VD located at the dim spots and bright lines is generated on both the rising and falling edges of the voltage.It is found that the high surface charge density transferred by the surface discharge of the bright spots promotes the formation of VD at the dim spots and bright lines.Finally,the emission line of the second positive band system of nitrogen molecules(C3?u?B3?g)and the argon atom of 696.57 nm(2P2?1S5)are also performed on the bright,dark and dark lines of the constituents in the super-four-sided speckle pattern with surface discharge.The widening of the spectral line,the relevant results obtained can also beconsistent with the previous results,and can further prove the correctness of the results of this study.Secondly,we report on a square super-lattice pattern by interaction of surface discharge with the applied voltage increasing in a dielectric barrier discharge system.The pattern consists of bright spots,bright lines,and dim spots.The spatio-temporal dynamics of the pattern is studied by photomultiplier(PMT),high speed video camera and normal camera.Results show that the bright spots discharge several times during each half cycle and they are formed by volume discharge(VD),bright line was formed by superposition of the surface discharges(SDs)over a long period of time,and the dim spots are consist of four small spots.The dim spots are formed by the repulsion of SDs.The light intensity of the bright and dim spots of the patch was compared and it was found that the ratio of the light intensity of the bright spot to the dark spot was about 10.The measurement of the emission spectroscopy show the parameters of the bright spots are different from that of the bright lines and dim spots,the discharge type of bright spots an dim spots is different,and reflects that the dim spots are formed by the interaction of SDs.The formation of the pattern is explained by the wall charge theory.