Listar por autor "Kelly, Héctor"
Mostrando ítems 1-20 de 29
-
Ambient Species Density and Gas Temperature Radial Profiles Derived from a Schlieren Technique in a Low Frequency Non-thermal Oxygen Plasma Jet.
Chamorro, Juan Camilo; Prevosto, Leandro; Cejas, Ezequiel; Kelly, Héctor; Mancinelli, Beatriz; Fischfeld, Gerardo (2017)A quantitative interpretation of the schlieren technique applied to a non-thermal atmospheric-pressure oxygen plasma jet driven at low-frequency (50 Hz) is reported. The jet was operated in the turbulent regime with a ... -
An Interpretation of Langmuir Probe Floating Voltage Signals in a Cutting Arc.
Prevosto, Leandro; Kelly, Héctor; Mancinelli, Beatriz (2009)An experimental study of the electrostatic probe floating voltage signals in a cutting arc and its physical interpre tation in terms of the arc plasma structure is reported. Sweeping electrostatic probes have been used ... -
Correlation methods in cutting arcs
Prevosto, Leandro; Kelly, Héctor (IOPscience, 2011-05-25)The present work applies similarity theory to the plasma emanating from transferred arc, gas-vortex stabilized plasma cutting torches, to analyze the existing correlation between the arc temperature and the physical ... -
Departures from local thermodynamic equilibrium in cutting arc plasmas derived from electron and gas density measurements using a twowavelength quantitative Schlieren technique.
Prevosto, Leandro; Artana, Guillermo; Kelly, Héctor; Mancinelli, Beatriz (2011)A two-wavelength quantitative Schlieren technique that allows inferring the electron and gas densities of axisymmetric arc plasmas without imposing any assumption regarding statistical equilibrium models is reported. ... -
Determination of plasma velocity from light fluctuations in a cutting torch.
Prevosto, Leandro; Kelly, Héctor; Mancinelli, Beatriz (2009) -
Effects of non–thermal plasmas on seed-borne Diaporthe/Phomopsis complex and germination parameters of soybean seeds.
Pérez Pizá, María Cecilia; Prevosto, Leandro; Zilli, Carla; Cejas, Ezequiel; Kelly, Héctor; Balestrasse, Karina (2018)Diaporthe/Phomopsis (D/P) is a complex of seed-borne fungi that severely affects soybean (Glycine max (L.) Merrill), one of the most important crops worldwide. Non-thermal plasma treatment is a fast, economic and ... -
Experimental Characterization of a Low-Current Cutting Torch.
Kelly, Héctor; Mancinelli, Beatriz; Prevosto, Leandro; Minotti, Fernando; Márquez, Andrés (2004)An experimental characterization of a low-current (30-40 A) cutting torch is presented. To avoid contamination of the plasma arc by removed anode material, a rotating steel cylinder was used as the anode and the arc ... -
Hydrodynamic Model for the Plasma-Gas Flow in a Cutting Torch Nozzle.
Kelly, Héctor; Minotti, Fernando; Prevosto, Leandro; Mancinelli, Beatriz (2004)We present a simple hydrodynamic model to obtain the profiles of the relevant physical quantities along a nozzle of arbitrary cross-section in a cutting torch. The model uses a two-zone approximation (a hot central ... -
Investigation of the relevant kinetic processes in the initial stage of a double-arcing instability in oxygen plasmas.
Mancinelli, Beatriz; Prevosto, Leandro; Chamorro, Juan Camilo; Minotti, Fernando; Kelly, Héctor (2018)A numerical investigation of the kinetic processes in the initial (nanosecond range) stage of the double-arcing instability was developed. The plasma-sheath boundary region of an oxygen operated cutting torch was considered. ... -
Langmuir probe diagnostics of an atmospheric pressure, vortex–stabilized nitrogen plasma jet
Prevosto, Leandro; Kelly, Héctor; Mancinelli, Beatriz (2012-09-19)Langmuir probe measurements in an atmospheric pressure direct current (dc) plasma jet are reported. Sweeping probes were used. The experiment was carried out using a dc non–transferred arc torch with a rod–type cathode ... -
Langmuir probe measurements in a time-fluctuating-highly ionized non-equilibrium cutting arc: Analysis of the electron retarding part of the time-averaged current-voltage characteristic of the probe.
Prevosto, Leandro; Kelly, Héctor; Mancinelli, Beatriz (2013)This work describes the application of Langmuir probe diagnostics to the measurement of the electron temperature in a time-fluctuating-highly ionized, non-equilibrium cutting arc. The electron retarding part of the ... -
Modelling of an Atmospheric Pressure Nitrogen Glow Discharge Operating in High-Gas Temperature Regimes.
Prevosto, Leandro; Kelly, Héctor; Mancinelli, Beatriz (2016)A model of an atmospheric pressure nitrogen glow discharge in high-gas tem perature regimes is developed. The model considers a fairly complete set of chemical reactions, including several processes with the participation ... -
Modelling of the Plasma–Sheath Boundary Region in Wall-Stabilized Arc Plasmas: Unipolar Discharge Properties.
Mancinelli, Beatriz; Prevosto, Leandro; Chamorro, Juan Camilo; Minotti, Fernando; Kelly, Héctor (2017)A two-dimensional model of the non-equilibrium unipolar discharge occurring in the plasma–sheath boundary region of a transferred-arc was developed. This model was used to study the current transfer to the nozzle (1 mm ... -
Numerical investigation of the double-arcing phenomenon in a cutting arc torch.
Mancinelli, Beatriz; Minotti, Fernando; Prevosto, Leandro; Kelly, Héctor (2014)A numerical investigation of the double-arcing phenomenon in a cutting arc torch is reported. The dynamics of the double-arcing were simulated by using a two-dimensional model of the gas breakdown development in the ... -
Numerical Modelling of a Cutting Arc Torch
Mancinelli, Beatriz; Minotti, Fernando Oscar; Prevosto, Leandro; Kelly, Héctor (Jan Awrejcewicz. INTECH, 2014-02-14)Plasma cutting is a process of metal cutting at atmospheric pressure by an arc plasma jet, where a transferred arc is generated between a cathode and a work-piece (the metal to be cut) acting as the anode . Small nozzle ... -
On the Double-Arcing Phenomenon in a Cutting Arc Torch.
Prevosto, Leandro; Kelly, Héctor; Mancinelli, Beatriz (2011)Transferred arc plasma torches are widely used in industrial cutting process of metallic materials because of their ability to cut almost any metal and the very high productivity that can be achieved with this technology ... -
On the dynamics of cutting arc plasmas: the role of the power supply ripple
Prevosto, Leandro; Mancinelli, Beatriz; Kelly, Héctor (ADVANCED ELECTROMAGNETICS, 2012-08)The power sources used in cutting arc torches are usually poorly stabilized and have a large ripple factor. The strong oscillatory components in the voltage and arc current produce in turn, large fluctuations in the plasma ... -
On the dynamics of the space-charge layer inside the nozzle of a cutting torch and its relation with the “non-destructive” double-arcing phenomenon
Prevosto, Leandro; Kelly, Héctor; Mancinelli, Beatriz (2011)Experimental observations on the plasma dynamics inside the nozzle of a 30 A oxygen cutting torch operated at conditions close to the double arcing are reported. It is employed a technique previously developed in our ... -
On the Gas Heating Mechanism for the Fast Anode Arc Reattachment in a Non-transferred Arc Plasma Torch Operating with Nitrogen Gas in the Restrike Mode.
Prevosto, Leandro; Kelly, Héctor; Mancinelli, Beatriz; Chamorro, Juan Camilo (2015)The present work provides a detailed kinetic analysis of the time-resolved dynamics of the gas heating during the arc reattachment in nitrogen gas in order to understand the main processes leading to such a fast reattachment. ... -
On the physical origin of the nozzle characteristic and its connection with the double-arcing phenomenon in a cutting torch.
Prevosto, Leandro; Kelly, Héctor; Mancinelli, Beatriz (2009)The nozzle current-voltage characteristic for a cutting arc is presented in this work. The measurements are reported using a high energy density cutting arc torch with a nozzle bore radius of 0.5 mm. The arc current was ...