介质阻挡放电中的八边形结构

Octagon structure in dielectric barrier discharge

采用双水电极介质阻挡放电装置,在放电间隙d值较大的实验条件下进行了斑图实验,实验首次得到了稳定的八边形结构,并对其演化序列和时空动力学进行了研究.实验发现,随外加电压的升高,系统经历了随机分布放电丝-大半径放电丝-八边形结构-失稳的八边形结构的演化过程.通过对其时空相关性测量,发现八边形结构在每半个电压周期内有2次放电.为了进一步研究八边形结构,实验还给出了斑图随空气体积分数和外加电压变化的相图,以及八边形结构随气体压强和外加电压变化的相图.

A stable octagon structure is firstly obtained and its evolvement and spatial-temporal dynamics are investigated by using the dielectric barrier discharge device with two water electrodes and with a relatively large d value. It is found that as the applied voltage increasing continuously a bifurcation scenario of the pattern follows as： random filaments--long radius filaments--the octagon structure--the instable octagon structure. The spatio- temporal correlation measurements indicate that there are two current pulses in each half of the applied voltage. In order to research the octagon structure further, the phase diagrams of the pattern as a function of air concentration and applied voltage, gas pressure and applied voltage are shown.