Propane Oxidation in a Plasma Torch of a Low-Current Nonsteady-State Plasmatron

This paper describes the investigation of an atmospheric-pressure glow discharge in air at a current of 0.05-0.3 A. Before the glow discharge is established, a preliminary nonsteady temporal stage is available in the gap. The principal process, which governs with the nonsteady-state discharge behavior, is the glow-to-spark transition phenomenon. The transition is initiated due to the explosive emission instability in the near-cathode layer of glow-type discharge that results in a microexplosion of the cathode surface and appearing of a spark cathode spot. At a low current, the spot is extinguished, so that the discharge starts burning again in one of the glow modes. After that, a new act of transition occurs and so on. The preliminary nonsteady-state stage ensures two prerequisites. First, an effective gas pressure decreases to a low value. Second, due to microexplosions, conditioning of the cathode surface is provided. Both factors facilitate establishing the normal glow discharge.Index Terms-Atmospheric-pressure plasma jets, glow-to-spark transition, high-pressure glow discharge.

Section: Regimes Of Discharge In Nonsteady-state Stagementioning

confidence: 65%

“…The obtained jets have the prospects for a variety of applications, such as surface modification [5], [16], decontamination and sterilization [5], [17], etching and deposition [4], medical and biomedical treatment [12]- [15], plasma catalytic conversion and plasma-assisted combustion [18]- [26], and the like.…”

Section: Introductionmentioning

confidence: 99%

Transient Processes During Formation of a Steady-State Glow Discharge in Air

Korolev

Франц

Geyman

et al. 2012

“…where w p is the power per unit positive volume, j is the current density, E is the electric field, T and T 0 are the positive volume and room temperatures, c p is the specific heat, n o is the gas density, and v T is the heat flow rate in fast gas flows v T = 2u d (12) where u is the gas velocity. Equation (12) represents the convective heat removal with the gas flow.…”

Section: F Voltage-current Characteristic Curve Regressionmentioning

confidence: 99%

“…I N RECENT years, plasma researchers have studied the reforming characteristics of all types of plasma [1]- [9], both thermal [2], [3], [5] and nonthermal [1], [4], [6], [10], in a fuel conversion system [5], [11] with many types of fuels [4], [7], [10]- [12]. Research has been largely focused on determining the plasma discharge for fuel reforming and improving the energy efficiency of a plasma system.…”

Section: Introductionmentioning

confidence: 99%

Electrical Characterization of a Reverse Vortex Gliding Arc Reactor in Atmosphere

Ding

2012

A new kind of gliding-arc reactor was designed for this study. A shape-memory-alloy electrode controls the discharge arc movement at the start of the discharge stage, while the root of the arc shifts to the ground electrode under normal operation. Experimental results for electrical parameters (voltage and current) in air were analyzed. When the power is adjusted from 50 to 70 W, the discharge waveform is close to sinusoidal at the condition of high power supply. The voltage-versus-current relationship was studied for the Reynolds number (Re number) ranging from 1174 to 2609, current ranging from 20 to 50 mA, and electrode gaps ranging from 11 to 24 mm. There is a linear relationship between root mean square (rms) voltage and the electrode gaps and an inverse linear relationship between rms voltage and rms current.

“…Originally, the plasmatron had been proposed in our papers for sustainment of 0093-3813/$31.00 © 2012 IEEE the combustion process in air/hydrocarbon mixtures [12]- [14], [47]. In such systems, the content of nitrogen oxides in a flue gas has to be as low as possible [48]- [50]. Then, the methods to suppress the oxide formation are reduced to the selection of the special conditions of the fuel burning and to the use of the repetitively pulsed discharges with short pulse duration [33], [38], [51], [52].…”

mentioning

confidence: 99%

Low-Current Plasmatron as a Source of Nitrogen Oxide Molecules

Korolev

Франц

Landl

et al. 2012

Self Cite

This paper describes a usage of a low-current coaxial plasmatron for generation of nitrogen oxide molecules. Glow-type discharge in vortex air flow is sustained at an average current from 0.05 to 0.2 A that corresponds to an average discharge power from 65 to 160 W. The diameter of an exit nozzle of the plasmatron is of 0.5 cm, and the air flow is varied from 0.2 to 1.5 g/s. In such conditions, the discharge burns in nonsteady-state regime, when a sustainment of a plasma jet/plume and a plasma column in the plasmatron nozzle is accompanied by the spontaneous glow-tospark transitions. Due to the special design of the anode nozzle, an efficient interaction of the air flow with the plasma plume and plasma column is provided. Typical contents of nitric monoxide in the output gas are of about several grams per cubic meter, and the cost for formation of one molecule is from 50 to 35 eV.