FRVT - Artículos en Revistas Internacionales

Permanent URI for this collectionhttp://48.217.138.120/handle/20.500.12272/396

Browse

Subject: search.filters.subject.Atmospheric pressure.

Search Results

Now showing 1 - 2 of 2
  • Thumbnail Image
    Item
    Cathode-sheath model for field emission sustained atmospheric pressure discharges
    (2021) Cejas, Ezequiel; Prevosto, Leandro; Minotti, Fernando; Ferreyra, Matías; Chamorro, Juan Camilo; Fina, Brenda
    The cathode-sheath region of a discharge in atmospheric pressure air with a flat copper cathode is numerically investigated by using a simple fluid model that takes into account non-local ionization. The effects of the cathode temperature are considered. Results are obtained in a wide current density range of 1–102 A/cm2 , which spans from normal glow discharge, through abnormal glow discharge, up to the early stages of the arcing transition. It is shown that the glow-to-arc transition arises from a field-emission instability at the cathode when the cur rent density is larger than 10 A/cm2 , i.e., when the cathode field exceeds a critical value of about 45 V/lm for the conditions considered. It is also shown that the cathode temperature significantly influences the cathode-sheath region. The proposed model is validated by comparing the numerical results with available experimental data.
  • Thumbnail Image
    Item
    Modelling of an Atmospheric Pressure Nitrogen Glow Discharge Operating in High-Gas Temperature Regimes.
    (2016) Prevosto, Leandro; Kelly, Héctor; Mancinelli, Beatriz
    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 of electronically exited nitrogen atoms describing the energy balance and charged particles kinetic processes in the dis charge. It is shown that the thermal dissociation of vibrationally excited molecules plays an essential role in the production of N(4 S) atoms. The dominant ion within the investigated current range (52–187 mA) is the molecular N2 ? with an increasing proportion of atomic N? towards high-current values. The process of production of electrons within the almost whole current range is controlled predominantly by associative ionization in atomic colli sions N(2 P) ? N(2 P) ? N2 ? ? e; being the N(2 P) atoms mainly produced via quenching of N2(A3Pu ?) electronically excited molecules by N(4 S) atoms. The results of calculations are compared with the available experimental data and a good agreement is found.