The Dielectric Effect In Scaled DBD And Optical Emission Spectroscopy Diagnosis Of DBD

The no-thermal plasma generated by dielectric barrier discharge (DBD) is one of the green technologies, which are applied to treatments of air and water. Existing plasma resources can't be used in treatment of ship's ballast water because of their limited scale and efficiency, but developing a scaled DBD plasma resource is held back by factors such as power supply, dielectric performance and so forth. The paper is supported by China National Natural Science Foundation (60371035) entitled 'The study of treating invasive spread of alien organism by gas discharge'.The paper focuses on the research of dielectric for scaled DBD plasma resource. In order to evaluate the potential of Al₂O₃ and enamel being used in scaled DBD, tests of dielectric performance of the materials are carried out, and the results are presented as following:The dielectric constant of Al₂O₃ is stable while being heated to 200℃. The AFM, XPS, AES tests show that the elements of the Al₂O₃ layer does not experience obvious change after being aged for 1000 hours, which suggests that the material is able to undergo long time operation of DBD plasma. Enamel is prepared by special processing in the lab, the test results illustrate that the dielectric performance of enamel is not as excellent as Al₂O₃, But the advantage of low cost makes the material competitive for scaled DBD.The optical emission spectroscopy is used to diagnose the electron excitation temperature of DBD with Al₂O₃ and enamel as dielectric, respectively. When the flow rate of Ar is 0.1m³/h, the electron excitation temperature is 0.33eV and 0.29eV, respectively. The determination of electron excitation temperature paves the way for establishing theory of scaled DBD plasma resource.