高压电极构型对DBD装置放电特性及臭氧生成的影响

Effect of High Voltage Electrode Geometry on the Discharge Characteristics and the Ozone Generation of a DBD Device

大气压介质阻挡放电(DBD)等离子体被广泛研究用于生物灭菌、材料表面改性、污染物净化处理等,而DBD装置的电极结构影响等离子体生成特性及其应用效果。为此,研究了不同高压电极构型(阵列针电极、网电极、平板电极)对DBD装置的放电特性、臭氧生成特性的影响。结果表明:网孔尺寸影响网电极的电流脉冲幅值、丝状电流脉冲数目和放电功率,网孔尺寸为0.2 mm×0.2 mm的网电极放电时的丝状电流脉冲数目大、电流脉冲幅值高,而网孔尺寸为0.5 mm×0.5 mm的网电极放电时的放电功率大;平板电极放电时的电流脉冲幅值高于网电极(网孔尺寸为0.5 mm×0.5 mm)和阵列针电极放电时的电流脉冲幅值,而平板电极的放电功率与网电极的放电功率相差不大,但远大于阵列针电极的放电功率;不同网孔尺寸的网电极放电时,在相同电压下,网孔尺寸为0.5 mm×0.5 mm的网电极放电时生成的臭氧质量浓度最高,且其生成的臭氧质量浓度和生成臭氧的能量效率均高于平板电极和阵列针电极。

Dielectric barrier discharge（DBD） plasma at atmospheric pressure has been extensively studied for sterilization, materials modification, pollutants treatment, etc. Geometry of the high voltage electrode in a DBD device influences the plasma characteristics, and therefore influences the performance of DBD devices in its material and environmental application.We studied the effects of different high voltage electrode geometries including needle array, mesh and plate on the discharge characteristics and ozone generation. Results indicate that the size of mesh pore affects the amplitude and number of current pulses and the discharge power, and the bigger amplitude and frequency of current pulse are obtained using the mesh electrode with a pore size of 0.2 mm×0.2 mm, but the biggest discharge power is obtained using the mesh electrode with a pore size of 0.5 mm×0.5 mm; the amplitude and number of current pulses using a metal plate as the high voltage electrode is higher than that of mesh and needle array electrodes, but the discharge power of plate electrode is similar to that of mesh electrode, and higher than that of needle array electrode. For mesh electrode, the highest ozone mass concentration is produced at the same applied voltage using the mesh with a pore size of 0.5 mm×0.5 mm, and the ozone mass concentration and its energy yield using metal mesh as the high-voltage electrode are higher than those of plate and needle array electrodes.