Listar FRVT - Artículos en Revistas por fecha de publicación
Mostrando ítems 1-20 de 58
-
Experimental Characterization of a Low-Current Cutting Torch.
(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.
(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 ... -
On the use of the metallic nozzle of a cutting arc torch as a Langmuir probe.
(2008)The region inside the nozzle (bore diameter ≈1 mm) of a cutting arc torch is inaccessible to most plasma diagnostics, and numerical simulations are the only means to find out the relative importance of several physical ... -
On the Use of Sweeping Langmuir Probes in Cutting-Arc Plasmas—Part II: Interpretation of the Results.
(2008)A semiempirical Langmuir probe model is intro duced that is particularly adapted to high-energy-density cutting arcs, for which, as we have shown in Part I, the ion current collected by negatively biased probes shows no ... -
On the Use of Sweeping Langmuir Probes in Cutting Arc Plasmas—Part I: Experimental Results.
(2008)The first study of Langmuir probes applied to cut ting arcs using a sweeping-probe system is presented. It is found that, under a relatively broad range of experimental conditions (changes in the probe material, in the ... -
On the space-charge boundary layer inside the nozzle of a cutting torch.
(2009)A numerical study of the space-charge sheath adjacent to the nozzle wall of a cutting torch is presented. The hydrodynamic model corresponds to a collision-dominated sheath and does not assume cold ions, so drift-diffusion-type ... -
On the physical origin of the nozzle characteristic and its connection with the double-arcing phenomenon in a cutting torch.
(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 ... -
An Interpretation of Langmuir Probe Floating Voltage Signals in a Cutting Arc.
(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 ... -
On the influence of the nozzle length on the arc properties in a cutting torch
(2009)In this work, an experimental study on the influence of the nozzle geometry on the physical properties of a cutting arc is reported. Ion current signals collected by an electrostatic probe sweeping across a 30 A oxygen ... -
Schlieren technique applied to the arc temperature measurement in a high energy density cutting torch.
(2010)Plasma temperature and radial density profiles of the plasma species in a high energy density cutting arc have been obtained by using a quantitative schlieren technique. A Z-type two-mirror schlieren system was used in ... -
Departures from local thermodynamic equilibrium in cutting arc plasmas derived from electron and gas density measurements using a twowavelength quantitative Schlieren technique.
(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. ... -
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
(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 use of the Prandtl mixing length model in the cutting torch modeling.
(2011-05-25)The Prandtl mixing length model has been used to take into account the turbulent effects in a 30 A high-energy density cutting torch model. In particular, the model requires the introduction of only one adjustable coefficient ... -
Correlation methods in cutting arcs
(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 ... -
On the dynamic behavior of the anode–arc–root at the nozzle surface in a non-transferred plasma torch
(2012)The dynamic behavior of the anode–arc–root at the nozzle surface of a plasma torch was experimentally investigated in this work. A gas (N2) vortex–stabilized non–transferred arc torch with a thoriated tungsten rod (2wt ... -
Numerical modeling of the gas breakdown development in the space–charge layer inside the nozzle of a transferred arc torch
(2012)Double–arcing is a phenomenon that occurs when a transferred arc, flowing inside an electrically insulated nozzle, breaks into two separate arcs: one that connects the cathode with the nozzle, and another that connects ... -
On the dynamics of cutting arc plasmas: the role of the power supply ripple
(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 ... -
Langmuir probe diagnostics of an atmospheric pressure, vortex–stabilized nitrogen plasma jet
(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.
(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 ...