Results 271 to 280 of about 380,531 (310)

Comparison of lightning return‐stroke models

Journal of Geophysical Research: Atmospheres, 1993
Five return‐stroke models, each allowing the use of measured channel‐base current and return‐stroke speed as inputs for the computation of channel current distribution and remote electric field, are compared and evaluated using 18 sets of three simultaneously measured triggered lightning features: channel‐base current, return‐stroke speed, and electric
Rajeev Thottappillil, Martin A. Uman
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Mathematical modelling of return strokes

2003
A lightning flash is initiated by electrical breakdown of the air in a cloud. This process, commonly known as the preliminary breakdown, signifies the initiation of a stepped leader. Such a stepped leader propagates towards the earth, in a succession of nearly discontinuous surges or steps. The stepped leader leaves a charged, conducting channel in its
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A model for subsequent return strokes

Journal of Electrostatics, 1993
Abstract In this paper a new return stroke model is introduced which is capable of predicting the temporal and spatial variation of the return stroke current and retunrn stroke velocity. The model predictions concerning the electromagnetic fields, return stroke current and return stroke velocity are in good agreement with experimental observations ...
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Magnetic field of lightning return stroke

Journal of Geophysical Research, 1969
The magnetic flux density due to first and to subsequent lightning return strokes is calculated for distances from the strokes of 0.5 to 200 km. The basis of the calculations is various assumed forms for the channel current as a function of time and of channel height. Two new channel-current models are introduced for first strokes and one new model for
Martin A. Uman, D. Kenneth McLain
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Wavelet analysis of lightning return stroke

Journal of Atmospheric and Solar-Terrestrial Physics, 2008
In this investigation, time series consisting of electric field waveforms of 15 positive return strokes and 10 negative return strokes were analyzed. The data came from a summer thunderstorm in March in a range of about 200 km around Sao Jose dos Campos, Sao Paulo.
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KARAKTERISTIK RISE TIME FIRST RETURN STROKE DAN SUBSEQUENT RETURN STROKE PADA PETIR NEGATIF KE TANAH

2015
Penelitian ini dilakukan terhadap 100 kejadian petir di Kota Padang Sumatera Barat dari bulan Agustus sampai Oktober 2014. Petir yang di analisis adalah petir negatif awan ke tanah. Sinyal petir di rekam dengan memanfaatkan antena medan listrik (fast antenna). Analisis yang dilakukan adalah pengukuran rise time untuk setiap sambaran balik (first return
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Channel heating in return-stroke lightning

Journal of Geophysical Research, 1971
A computer code for calculating radiation flow and hydrodynamic motion has been used to investigate the radial-temperature and time-temperature profiles of an air channel heated by a single return stroke of lightning. The investigation used a novel model in which input heat releases were computed from calculated electrical conductances of channel zones
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Return stroke models for engineering applications

2010
In this chapter, we will describe and discuss several engineering models that can be utilized either to evaluate electromagnetic fields from lightning flashes or to study the direct effects of lightning attachment to various structures including tall towers. We will start by describing the basic concepts of engineering return stroke models.
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Lightning return stroke and its modeling

2020
In this chapter, we give an overview of lightning discharges, which can cause electromagnetically induced effects in power and telecommunication systems. Then, we describe modeling of the lightning return stroke and explain “engineering” models, in which the spatial and temporal distribution of the current or the line charge density along the lightning
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return stroke, n.

2023
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