THE STUDY OF ELECTRICAL PARAMETERS AND THE EXHAUST GAS ANALYSIS FOR A DOUBLE SPARK PLUG

Abstract The spark produced by a classical spark-plug does not always assure a fast and complete combustion of an air/fuel mixture into the combustion chamber of a thermal engine. This is the reason why we have done a long series of studies on this subject and a new type of spark plug with three electrodes has been proposed, using two different simultaneous electrical discharges generated by a high voltage power supply. The new type of spark plug should produce a larger and more homogeneous volume of plasma into the engine's combustion chamber that can assure a faster and complete combustion of the air/fuel mixture. To validate the functionality of the proposed ignition system physical, mechanical, electrical and chemical analysis have been done in order to reveal its benefits comparing with a classical ignition system. In this paper we present a comparison between the electrical parameters, respectively the exhaust gas parameters, when using in a single cylinder engine a classical spark plug and a double spark plug. The electrical parameters of the discharges have been measured in air, at atmospheric pressure and temperature and also when the spark plug was mounted into the cylinder heads. The exhaust gases were analyzed using a ROTRONICS CMR101 air/fuel acquisition system that allows the measurement of the oxygen ratio in the exhaust gas of the thermal engines

Destruction plasmachimique d’urée et de thiourée par décharge électrique à pression atmosphérique

Le traitement à la pression atmosphérique de solutions aqueuses d’urée et de thiourée par plasma d’arc rampant en atmosphère d’air humide conduit à la dégradation totale de ces composés. Les cinétiques globales d’ordre nul ont des constantes voisines proches de 3•10‑6 s‑1. Le procédé met en jeu les espèces actives créées dans la décharge, les radicaux OH et NO, responsables des caractères chimiques principaux du plasma : oxydation du fait de la présence de OH (E°OH H2O =  2,85 V/ENH) et acidification, provenant de la formation d’acides nitreux et nitrique en solution. Ces résultats sont relatifs à des molécules modèles, mais suggèrent l’extension du procédé à la dégradation de molécules toxiques et d’effluents industriels soufrés.Electric discharges in humid air (i.e., a gliding arc discharge at atmospheric pressure and quasi-ambient temperature) are considered in the context of evaluating new techniques for pollution abatement. An electric discharge in a gas under specific conditions gives rise to a plasma, which involves activated gas species with enhanced reactivity. The main chemical properties of a discharge in humid air are attributed to NO and OH radicals formed in the discharge, which are able to react with solutes at the plasma/liquid interface. These activated species are formed in advanced oxidation processes and are respectively responsible for acid and oxidizing effects in the target solution: NO gives rise to nitrous and nitric acids, and OH is strongly oxidising [E°(OH/H2O) =  2.85 V/NHE].To examine the degradation power of the plasma treatment on molecules of the same family and to evaluate the ability of the gliding arc system to oxidize sulphur-containing solutes (2 x 10‑3 M) in batch conditions, aqueous urea and thiourea were selected as suitable target solutions. The solutes were completely degraded within 180‑200 minutes of treatment and the concentrations decreased linearly with increasing exposure times in the discharge. This trend accounts for overall zero-order kinetic schemes with the relevant rate constants of kurea = 5.28 x 10‑6 s‑1 and kthiourea = 2.03 x 10‑6 s‑1.The evolution of solutes with time was followed by total organic carbon (TOC) measurements for urea, and by the conductometric titration of the sulphate ions formed in the case of thiourea. Spectrophotometric measurements of the treated solutions at the solute absorption peaks were found to be unsuitable for analysis purposes due to the formation of nitrite/nitrate ions which absorb in the same wavelength range.The extension of a gliding arc system from the laboratory level to an industrial scale for pollution abatement of industrial effluents is considered

Toxicity assessment of long-term exposure to non-thermal plasma activated water in mice

Non-thermal plasma activated water (PAW) has recently emerged as a powerful antimicrobial agent. Despite numerous potential bio-medical applications, studies concerning toxicity in live animals, especially after long-term exposure, are scarce. Our study aimed to assess the effects of long-term watering with PAWon the health of CD1 mice. PAWwas prepared from distilled water with a GlidArc reactor according to a previously published protocol. The pH was 2.78. The mice received PAW(experimental group) or tap water (control group) daily for 90 days as the sole water source. After 90 days, the following investigations were performed on the euthanatized animals: gross necropsy, teeth mineral composition, histopathology, immunohistochemistry, hematology, blood biochemistry, methemoglobin level and cytokine profile. Mice tolerated PAWvery well and no adverse effects were observed during the entire period of the experiment. Histopathological examination of the organs and tissues did not reveal any structural changes. Moreover, the expression of proliferation markers PCNA and Ki67 has not been identified in the epithelium of the upper digestive tract, indicating the absence of any pre- or neoplastic transformations. The results of our study demonstrated that long-term exposure to PAWcaused no toxic effects and could be used as oral antiseptic solution in dental medicine

The study of an electric spark for igniting a fuel mixture

Communication orale (B.Hnatiuc)International audienc

Electrical and Physical Properties of a Gliding Arc

[Communication orale (B.Hnatiuc)]International audienc

The study of the electrical parameters and the exhaust gas analysis for a double spark plug

[Poster

Experimental analysis of a double-spark ignition system

International audienceThe spark that ignites the combustible mixtures is a discharge produced between the electrodes of a spark plug, connected to the secondary of a coil at the high voltage. Optimum combustion requires a steady spark, in a volume as large as is possible, and with maximum energy. We propose a solution to increase the plasma volume and present electrical discharge parameters as a function of inter-electrode distances, pressures in the test-reactor and the width of the electrical pulses of the power supply

Gliding spark used for ignition system

International audienc

The study of the electrical parameters and the exhaust gas analysis for a double spark plug

[Post-Publication SIELMEN 2011