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Point-discharge currents from natural and artificial points

✍ Scribed by J. E. Maund; J. Alan Chalmers

Publisher
John Wiley and Sons
Year
1960
Tongue
English
Weight
491 KB
Volume
86
Category
Article
ISSN
0035-9009

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✦ Synopsis

Abstract

When point discharge occurs at an earth‐connected point, ions of one sign travel to earth through the point while ions of opposite sign travel away in the wind. This stream of ions reduces the potential gradient at the ground to leeward of the point below that to windward. Theory shows that, under suitable conditions, this difference in potential gradient is close to that predicted for a line of charge, even though the line is spread into a cone by turbulent diffusion. Measurements with point discharge from a 34 m mast show good agreement with theory, and this makes it possible to use the difference of potential gradient to determine the point‐discharge current through a tree. When applied to a line of trees, seasonal differences are found suggesting smaller currents from trees in leaf than from bare trees. Measurements with a 12 m sycamore tree in full leaf show no point‐discharge current even in potential gradients up to 7,000 v/m.

πŸ“œ SIMILAR VOLUMES

Point-discharge currents and the earth's
Point-discharge currents and the earth's electric field
✍ W. C. A. Hutchinson πŸ“‚ Article πŸ“… 1951 πŸ› John Wiley and Sons 🌐 English βš– 381 KB

## Abstract An account is given of measurements of the current flowing to earth through a point set up at a height of 12 m, together with the electric field near the ground. Point‐discharge current of either sign may be represented approximately as increasing with the square of the field, as found