Symmetrical Gaps Research Articles

Spatial stabilization of Townsend discharge in a modified ionization cell with symmetrical short gaps between semiconductor plate and electrodes

A Townsend-type discharge generated in a modified ionization cell with symmetrical short gaps between a high-resistivity semiconductor plate and two planar electrodes is studied. The spatial stabilization of the gas discharge cell with a planar GaAs semiconductor plate is studied over a wide range of gas pressure values 101-342 Torr. The characteristics of the system are obtained both without and with illumination of the semiconductor plate with light of a particular wavelength range to control the photoconductivity of the material. The semiconductor material is found to stabilize the discharge. It is shown that generation of carriers by a gas discharge establishes a positive feedback. A qualitative discussion of this effect is given, which includes avalanche formation in a system having high-resistivity semiconductor for the Townsend discharge region. Recording of the current-voltage characteristic between parallel-plane electrodes is realized.

A semiconductor photographic system with a modified cell

This paper studies a modified photographic cell with symmetrical short gaps between a high-resistivity detector plate and two planar electrodes. The photographic system with a modified cell is designed to optimize the parameters for the enhancement of the resolution in such applications. The spatial stabilization of the current in the modified cell with a planar GaAs photodetcctor is studied in a wide range of gas pressure values at 101-342 Torr. Characteristics of the photographic system are obtained both without and with illumination of the detector plate with light of a particular wavelength range used to control the photoconductivity of the material. The current voltage characteristic (CVC) and the photographic cell response are recorded.

Comparison of the breakdown of rod-plane gaps with floating electrode

The possible influence of a metal body in a lightning protection system was determined by comparing the electrical breakdown probability of two symmetrical sphere-rod gaps, one conventional and the other with a floating electrode, i.e. a rod with a series gap introduced in its conducting path. 50 switching voltage impulses were applied to the arrangement for each series-gap length. The breakdown probability was obtained for each rod as a function of the series-gap length. The results show that the rod with a series gap shows the same breakdown probability as the conventional rod for a certain limited range of the series-gap length. Beyond this range the conventional rod has always a higher breakdown probability. The analysis of the actual breakdown voltage in different configurations has shown some differences in the physical process that lead to breakdown in different arrangements.

5614880 Superconducting magnet with symmetrical plural AIR gaps

5614880 Superconducting magnet with symmetrical plural AIR gaps

Simulations Of Swirling Fires Controlled By Channeled Self-generated Entrainment Flows

In an earlier study experimental observations of swirling fires based on self-generated swirling flows were undertaken. The swirl was caused by properly channeling the entrainment flow due to the fire itself. It was found that one of the most significant parameters governing the combustion process and the stability of the whirling flame was the entrainment flow controlled by the presence of symmetrical gaps separating the square vertical bounding walls surrounding the fire. In the present study, the physical phenomena of how the channeled entrainment flow affects the whirling flame has been simulated numerically by an approximate fire field model, which captures essentially the same whirling fire phenomena as observed in the experiments. In particular, the quantitative effect of gap sizes between bounding walls and several other parameters such as heat load, fuel size, and enclosure wall height on the plume dynamics and whirling flame stability have been numerically determined.

Atmospheric Influences on the Switching Impulse Performance of I-Meter Gaps

This paper deals with the effects of atmospheric conditions on the flashover characteristics ics of non-uniform symmetrical field air gaps. Special emphasis is placed on the investigation of these effects with regards to the use of open air, protective gaps on high voltage power systems.