فهرس المقالات discharges

• حرية الوصول المقاله
  • صفحة الملخص
  • نص كامل
  
  1 - Analysis of discharge parameters and optimization study of coaxial DBDs for efficient excimer light sources
  Udit Narayan Pal Pooja Gulati Niraj Kumar Mahesh Kumar Vishnu Srivastava Ram Prakash
  10.1186/2251-7235-6-41
  AbstractIn this work, a xenon-filled quartz coaxial dielectric barrier discharge (DBD) tube (ID 6 mm, OD 12 mm) at 400-mbar pressure has been studied at different operating conditions. High-frequency sinusoidal and unipolar pulse-like voltages are applied at the dischar أکثر

  AbstractIn this work, a xenon-filled quartz coaxial dielectric barrier discharge (DBD) tube (ID 6 mm, OD 12 mm) at 400-mbar pressure has been studied at different operating conditions. High-frequency sinusoidal and unipolar pulse-like voltages are applied at the discharge electrodes for the generation of micro-discharge plasma. Visual images of the discharge and the electrical waveform confirm the diffused-type discharge. The mechanism that is involved in the ignition, development and extinction of DBDs is quantitatively explained by dynamic processes in the discharge. An equivalent electrical model representing the DBD phenomenon has also been used to validate the characteristic discharge parameters. The relative intensity analysis of the Xe continuum peak at wavelength 172 nm in the optical emission spectra of the vacuum ultraviolet region has been carried out for different operating conditions. Approximately three times increment in the radiation is observed in pulse excitation over sinusoidal excitation. It infers that the pulsed excitation of DBD sources is advantageous for excimer light sources. تفاصيل المقالة
• حرية الوصول المقاله
  • صفحة الملخص
  • نص كامل
  
  2 - A parametric study on the PD pulses activity within micro-cavities
  Alireza A. Ganjovi
  10.1007/s40094-015-0202-8
  AbstractA two-dimensional kinetic model has been used to parametric investigation of the spark-type partial discharge pulses inside the micro-cavities. The model is based on particle-in-cell methods with Monte Carlo Collision techniques for modeling of collisions. Secon أکثر

  AbstractA two-dimensional kinetic model has been used to parametric investigation of the spark-type partial discharge pulses inside the micro-cavities. The model is based on particle-in-cell methods with Monte Carlo Collision techniques for modeling of collisions. Secondary processes like photo-emission and cathode-emission are considered. The micro-cavity may be sandwiched between two metallic conductors or two dielectrics. The discharge within the micro-cavity is studied in conjunction with the external circuit. The model is used to successfully simulate the evolution of the discharge and yield useful information about the build-up of space charge within the micro-cavity and the consequent modification of the applied electric field. The phase-space scatter plots for electrons, positive, and negative ions are obtained in order to understand the manner in which discharge progresses over time. The rise-time and the magnitude of the discharge current pulse are obtained and are seen to be affected by micro-cavity dimensions, gas pressure within the micro-cavity, and the permittivity of surrounding dielectrics. The results have been compared with existing experimental, theoretical, and computational results, wherever possible. An attempt has been made to understand the nature of the variations in terms of the physical processes involved. تفاصيل المقالة
• حرية الوصول المقاله
  • صفحة الملخص
  • نص كامل
  
  3 - EFFECT OF ELECTRIC FIELD ON PD ACTIVITY AND DAMAGE INTO SOLID DIELECTRIC MATERIALS
  Alireza Ganjovi
  Abstract– In this paper, the effect of applied electric field on the damage due to partial discharges activity into the surroundings dielectrics of a narrow channel encapsulated within the volume of a dielectric material is evaluated using a kinetic model based on أکثر

  Abstract– In this paper, the effect of applied electric field on the damage due to partial discharges activity into the surroundings dielectrics of a narrow channel encapsulated within the volume of a dielectric material is evaluated using a kinetic model based on Particle in Cell - Monte Carlo Collision (PIC-MCC) model. After application of an electric field across a dielectric material which contains a narrow channel, repeated ionization process starts in the gaseous medium of narrow channel. Charged particles, especially electrons, gain energy from the electric field across narrow channel and cause damage into dielectric surfaces of narrow channel on impact. The dependence of the electron energy distribution function (EEDF) on the applied electric field is studied. It isseen that, during PD activity within narrow channel, the damage to the surrounding dielectrics and consequently the surface conductivity increases. These estimations are performed based on the number of C-H bond-scissions produced by the impacting electrons of a single PD pulse. Based on this technique, the consequent damage into the solid dielectric and the time required to increase surface conductivity is computed. The formation of acid molecules due to interaction of PD pulse with polymer surface in presence of air and humidity causes changes in the surface conductivity of the surrounding dielectrics of the narrow channels. تفاصيل المقالة