Electrical and optical emission measurements of a capillary dielectric barrier discharge

Abstract

The electrical and emission properties of a capillary DBD (Cap-DBD) plasma in atmospheric pressure air are reported in this work. The plasma reactor consists of metal wire electrodes inside quartz capillary tubes powered with a low kilohertz frequency AC high voltage power supply. Various reactor geometries (planar, 3-D multilayer, and circular) with no gap spacing up to a few hundred micron gaps were investigated. The discharges appear homogenous across the whole device at gaps between 0 and 225 μm and turned into filamentary discharges at larger gap spaces. The operating voltage was generally around 3-4 kV (RMS). The power consumption by the Cap-DBD was calculated using voltage/charge Lissajous figures with observed powers of a few tens of watts, reaching a maximum for a particular gap distance at 225 μm. Further studies of optical emission spectroscopy (OES) were employed to evaluate the reactive species generated in the microplasma source. The observed emission spectrum was predominantly within the second positive system of N 2 (C 3 Π u -B 3 Π g ) and the first negative system of N 2 + (B 2 Σ u + -X 2 Σ g + ).________________________________ *

Study of the Influence of Variation in Distances Between Electrodes in Spectral DBD Plasma Excitation

“…These values are shown in Table 3. These results are in full accordance with equation 2 18 . As the dielectric thickness is constant, the increase in distance between electrodes causes the decrease in the total capacitance of the reactor.…”

Thermal Characteristics of Helical Coiled Heat Exchanger with Graphene-Deionized Water on Waste Heat Recovery of Combustion Stack Gas

“…The discharge energy per cycle was calculated based on the area of the charge-voltage Lissajous figure (Kostov et al, 2010). The mean power consumption was calculated by multiplying the energy of each cycle by the source frequency (Mahoney et al, 2010). The charge-voltage Lissajous figure is a standard method for the electrical diagnostics of DBD discharges (Jiang et al, 2013).…”

Enduring and Stable Surface Dielectric Barrier Discharge (SDBD) Plasma Using Fluorinated Multi-Layered Polyimide

“…Typical peaks were identified according to Refs. [33][34][35] The typical parameters such as N2 (C 3 Пu) vibrational temperature (Tvib), electron temperature (Te) and N2 (C 3 Пu) rotational temperature (Trot) are important parameters to evaluate plasma characteristics. The relative intensity ratio between 371.1 and 380.5 nm (I371.1/I380.5) can be used as an indicator of Tvib; the relative intensity ratio between 391.4 and 380.5 nm (I391.4/I380.5) is used to obtain the temporal and spatial averaged Te by the line-ratio technique of OES [36,37].…”

“…[33][34][35], which included N 2 (C 3 Π u →B 3 Π g , 2-4) at 371.1 nm, N 2 (C 3 Π u →B 3 Π g , 1-3) at 375. Optical emission spectroscopy (OES) is used to study discharge plasma.…”

“…Typical peaks were identified according to Refs. [33][34][35], which included N2 (C 3 Пu→B 3 Пg, 2-4) at 371.1 nm, N2 (C 3 Пu→B 3 Пg, 1-3) at 375.5 nm, N2 (C 3 Пu→B 3 Пg, 0-2) at 380.5 nm, N2 + (B 2 Σu + →X 2 Σg + , 0-0) at 391.4 nm, N2 (C 3 Пu→B 3 Пg, 2-5) at 394.3 nm, and N2 (C 3 Пu→B 3 Пg, 1-4) at 399.5 nm. The typical parameters such as N2 (C 3 Пu) vibrational temperature (Tvib), electron temperature (Te) and N2 (C 3 Пu) rotational temperature (Trot) are important parameters to evaluate plasma characteristics.…”