ISSN 1063-780X, Plasma Physics Reports, 2009, Vol. 35, No. 4, pp. 329–342. © Pleiades Publishing, Ltd., 2009. Original Russian Text © S.V. Avtaeva, E.B. Kulumbaev, 2009, published in Fizika Plazmy, 2009, Vol. 35, No. 4, pp. 366–380. 329 1. INTRODUCTION Dielectric barrier discharges (DBDs) in mixtures of noble gases are widely used as vacuum UV sources in excimer lamps and plasma display panels (PDPs). In recent years, DBDs have received extensive studies aimed at increasing their energy efficiency [1–6]. Because of the very short gap lengths and short dura- tions of microdischarges, the spatiotemporal charac- teristics of DBDs are rather difficult to measure exper- imentally. Therefore, in some works (see, e.g., [7–9]), DBDs excited in macroscopic PDP cells with dimen- sions that are one to two orders greater than those of actual PDP cells were investigated. In this case, it is assumed that the discharges are similar and that the DBD processes in macroscopic PDP cells are similar to those in actual cells, provided that, besides geomet- ric similarity, some other conditions are satisfied. In particular, the parameters pd and pT (where p is the gas pressure, d is the gap length, and T is the ac voltage period), the voltage amplitude, the gas temperature, and the gas composition must be the same. When all these conditions are satisfied, such combinations of the gas pressure and the internal DBD parameters as the reduced current density J/p 2 , the reduced electric field E/p, and the reduced electron and ion densities N e, i /p 2 in macroscopic and actual PDP cells are expected to be the same [10–13]. In the present paper, the DBD similarity and the invariance of the above combinations of the parame- ters of DBDs excited between two plane-parallel elec- trodes coated with dielectric layers are analyzed numerically. Established regimes of two DBDs in the 0.95 Ne/0.05 Xe mixture are simulated in a one- dimensional drift-diffusion model for the same values of the parameters pd and pT. In Section 2, the diffu- sion-drift DBD model and the kinetic scheme of ele- mentary physicochemical processes in a neon-xenon mixture are briefly described. In Section 3, the devel- opment and parameters of DBDs are considered, the DBD similarity is analyzed, the invariance of combi- nations of the discharge parameters is verified, and reasons by which such invariance can be violated are discussed. 2. ONE-DIMENSIONAL DRIFT-DIFFUSION DBD MODEL Let us consider a DBD excited between two plane- parallel dielectric-coated electrodes, to which an ac voltage with a given frequency and amplitude is applied. The transverse dimensions of the electrodes are assumed to be substantially greater than the elec- trode gap length, so the parameters of the discharge plasma vary only in the direction perpendicular to the electrodes. The drift-diffusion model of a DBD is based on the continual description of plasma (see [14] for details). Since the mobility of plasma ions is low, their drift-dif- fusion motion is determined by the local electric field, whereas their densities satisfy the standard one- dimensional continuity equations. The electron com- ponent is described by the continuity equation and the equation of electron energy balance, which approxi- mately takes into account the nonlocal character of the electron energy distribution function (EEDF) [15]. The electric field is defined through the scalar potential, which satisfies Poisson’s equation. Time variations in the densities of neutral particles are determined by their production and loss in elementary physicochemical processes described by the kinetic scheme. The set of equations is supplemented with boundary conditions on the surfaces of the dielectric barriers. The initial conditions correspond to spatially LOW-TEMPERATURE PLASMA Numerical Analysis of Similarity of Barrier Discharges in the 0.95 Ne/0.05 Xe Mixture S. V. Avtaeva and E. B. Kulumbaev Kyrgyz-Russian Slavic University, Bishkek, Kyrgyz Republic Received July 7, 2008 Abstract—Established dynamic regimes of similar (with a scale factor of 10) barrier discharges in the 0.95 Ne/0.05 Xe mixture are simulated in a one-dimensional drift-diffusion model. The similarity is exam- ined of barrier discharges excited in gaps of lengths 0.4 and 4 mm at gas pressures of 350 and 35 Torr and dielectric layer thicknesses of 0.2 and 2 mm, the frequencies of the 400-V ac voltage applied to the discharge electrodes being 100 and 10 kHz, respectively. PACS numbers: 52.80.Tn, 52.65.Kj, 52.65.Ww, 82.33.Xj DOI: 10.1134/S1063780X09040060