No abstract available

No abstract available

[en] This paper is aimed at investigating the inception voltage of the positive corona in point-to-plane gaps in atmospheric air as influenced by a surrounding dielectric enclosure. First, the method of calculation of the inception voltage is explained. It is based on the criterion of self-sustained growth of onset streamers. This calls for calculating the electric field in the vicinity of the stressed point with and without the surrounding enclosure. Then, the calculated inception voltages are compared with those measured experimentally

[en] A method is developed for calculating the induced voltages on fence wires/pipelines underneath AC power transmission lines. The method is based on the charge simulation technique and takes into account the disturbances of the electric field and potential due to the presence of the fence wire/pipeline underneath the line. The calculated values of the induced voltage on fence wires are compared with those measured before. Induced voltages on pipelines underneath 230- and 380-kV lines are measured, correlated to the calculated values and discussed in the light of electric field induction on objects adjacent to AC power transmission lines

[en] This paper is aimed for investigating the effect of surface coating on the positive and negative onset voltages of corona from stressed conductor as a pre-requisite for onset-voltage calculation. The electric field is accurately calculated by the charge simulation technique. The calculated onset voltages agreed satisfactorily with those measured experimentally for bare conductors. The effect of coating-layer thickness and permittivity as well as conductor radius and height on the onset-voltage values is discussed

[en] This paper is aimed at assessing analytically the dc corona induced pressures in wire-cylinder and wire-plate electrostatic precipitator configurations. This calls for solving the equations describing the corona discharge and the force balance for static gas equilibrium provided that the corona onset voltage and the space-charge-free field values are calculable. The calculated pressure and potential distributions along the gap axis in air and nitrogen at atmospheric pressure agreed well with those measured previously. The calculated corona current density values agreed reasonably with those measured for a high-temperature high-pressure wire-cylinder precipitator. The analytically calculated positive and negative dc corona onset voltages for wire-duct precipitators following proposed criteria based on discharge physics are in good agreement with those measured experimentally at atmospheric and lower pressures

[en] This paper aims to study the interaction between discharges taking place in the stressed air volume of a point-to-point gap and the charge accumulating on a nearby dielectric surface due to these discharges. For the discharge to be confined to one point electrode of the gap, the tip radius of that electrode was chosen to be much smaller than that of the other electrode. Experiments have been carried-out with 250/2500-μs switching impulse or dc voltage applied to the point electrode in the presence of a dielectric plate form plexiglas (PMMA). All measurements are discussed in the light of gas-discharge physics

[en] This paper is aimed at investigating culturing of living cells as influenced by exposure to AC and DC ionized and non-ionized fields in a point-to-plane gap. A cell suspension including yeast was placed on the ground plane at the gap axis and exposed to AC and DC fields of varying magnitudes. The effect of exposure time, frequency of the AC fields and magnitude of the applied fields on the survival rate of cells was investigated. The survival rate was also investigated as influenced by blowing the ionized field by air.

[en] This paper is aimed at investigating the characteristics of a sliding discharge (SD) including the onset voltage (V_o), spark voltage (V_S), and current-voltage (I-V) relationship in a multi-rod reactor stressed by sinusoidal AC or pulse voltage. The effects of various parameters (the voltage amplitude, frequency, gas flow rate, and voltage type) on the characteristics of the reactor sliding discharge (V_o, V_S and I-V relationship) have been studied experimentally. It has been found that the DC onset and spark voltages increase with the increase of the gas flow rate, while the effect of the frequency on them is not pronounced. The onset and spark voltages of the stressed reactor for sinusoidal AC voltage are lower than those obtained under a pulse voltage of the same peak value. Subsequently, the sliding current increases with the increase of the sinusoidal AC high voltage, the frequency, and the negative DC voltage, while, it decreases with the increase of the flow rate. It is observed that stressing the reactor with sinusoidal AC voltage gives higher values of sliding current than those obtained using a pulse at the same peak voltage. Stressing the reactor with sinusoidal AC voltage gives higher values of the NO removal efficiency than those obtained using pulse voltage.

[en] This paper is aimed at investigating theoretically and experimentally the corona ion-flow characteristics in coaxial gap configurations, where the corona wire is extended along the axis of a grounded meshed cylinder. The characteristics include the corona current and electric wind velocity at varying values of the applied voltage for different meshed cylinders. The measured corona current-voltage characteristics were compared with those of smooth cylinders of the same diameter as the meshed ones. The calculated corona currents and wind velocities agreed reasonably with those measured at different applied voltages.