介质阻挡放电中等离子体子弹的速度

On the velocity of plasma bullet generated in a dielectric barrier discharge

利用针板介质阻挡放电装置,采用光学方法对大气压长间隙空气放电的等离子体羽特性和等离子体子弹速度进行了研究.结果表明:改变外加电压等离子体羽长度会发生变化.利用光电倍增管采集光信号对等离子体子弹速度进行了研究,发现等离子体子弹的速度与针板间距、外加电压以及针尖直径有关.利用光谱仪采集放电的发射光谱,发现放电等离子体中存在OH自由基、氧原子等多种活性粒子,表明该放电在生物医疗领域具有重要的应用价值.

The characteristics of the plasma plume and plasma bullet are investigated in atmospheric pressure air through optical method by using a dielectric barrier discharge device in needle-plate configura- tions. Results indicate that the length of the plasma plume changes with varying the amplitude of the ap- plied voltage. The light emission signals from the discharge are detected by photomultiplier tubes. By spa- tial-resolved measurement, the spatial distribution of velocity for plasma bullet propagation is calculated. The results show that the propagation velocity of plasma bullet is functions of the physical parameters such as the gas gap width between the needle and the plate, the amplitude of the applied voltage and the diame- ter of the tip. The emission spectrum is collected by a spectrometer, and emissions from oxygen atoms, OH radicals and many other active particles can be found in the optical emission spectrum, which indicates that the discharge has application potentials in biomedical field.