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Title: Thermal power and heat energy of cloud-to-ground lightning process

Abstract

A cloud-to-ground lightning flash with nine return strokes has been recorded using a high speed slitless spectrograph and a system composed of a fast antenna and a slow antenna. Based on the spectral data and the synchronous electric field changes that were caused by the lightning, the electrical conductivity, the channel radii, the resistance per unit length, the peak current, the thermal power at the instant of peak current, and the heat energy per unit length during the first 5 μs in the discharge channel have all been calculated. The results indicate that the channel radii have linear relationships with the peak current. The thermal power at the peak current time increases with increasing resistance, but exponential decays with the square of the peak current.

Authors:
; ;  [1];  [2]
  1. Key Laboratory of Atomic and Molecular Physics and Functional Materials of Gansu Province, College of Physics and Electronic Engineering, Northwest Normal University, Lanzhou 730070 (China)
  2. School of Physics and Information Engineering, Shanxi Normal University, Linfen 041004 (China)
Publication Date:
OSTI Identifier:
22600057
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physics of Plasmas; Journal Volume: 23; Journal Issue: 7; Other Information: (c) 2016 Author(s); Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
70 PLASMA PHYSICS AND FUSION TECHNOLOGY; 75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; ANTENNAS; AUGMENTATION; CLOUDS; DECAY; ELECTRIC CONDUCTIVITY; ELECTRIC FIELDS; HEAT; LENGTH; LIGHTNING; PEAKS; VELOCITY

Citation Formats

Wang, Xuejuan, Yuan, Ping, Xue, Simin, and Cen, Jianyong. Thermal power and heat energy of cloud-to-ground lightning process. United States: N. p., 2016. Web. doi:10.1063/1.4956442.
Wang, Xuejuan, Yuan, Ping, Xue, Simin, & Cen, Jianyong. Thermal power and heat energy of cloud-to-ground lightning process. United States. doi:10.1063/1.4956442.
Wang, Xuejuan, Yuan, Ping, Xue, Simin, and Cen, Jianyong. Fri . "Thermal power and heat energy of cloud-to-ground lightning process". United States. doi:10.1063/1.4956442.
@article{osti_22600057,
title = {Thermal power and heat energy of cloud-to-ground lightning process},
author = {Wang, Xuejuan and Yuan, Ping and Xue, Simin and Cen, Jianyong},
abstractNote = {A cloud-to-ground lightning flash with nine return strokes has been recorded using a high speed slitless spectrograph and a system composed of a fast antenna and a slow antenna. Based on the spectral data and the synchronous electric field changes that were caused by the lightning, the electrical conductivity, the channel radii, the resistance per unit length, the peak current, the thermal power at the instant of peak current, and the heat energy per unit length during the first 5 μs in the discharge channel have all been calculated. The results indicate that the channel radii have linear relationships with the peak current. The thermal power at the peak current time increases with increasing resistance, but exponential decays with the square of the peak current.},
doi = {10.1063/1.4956442},
journal = {Physics of Plasmas},
number = 7,
volume = 23,
place = {United States},
year = {Fri Jul 15 00:00:00 EDT 2016},
month = {Fri Jul 15 00:00:00 EDT 2016}
}
  • Using the spectra of a cloud-to-ground (CG) lightning flash with multiple return strokes and combining with the synchronous radiated electrical field information, the linear charge density, the channel radius, the energy per unit length, the thermal energy, and the energy of dissociation and ionization in discharge channel are calculated with the aid of an electrodynamic model of lightning. The conclusion that the initial radius of discharge channel is determined by the duration of the discharge current is confirmed. Moreover, the correlativity of several parameters has been analyzed first. The results indicate that the total intensity of spectra is positive correlatedmore » to the channel initial radius. The ionization and thermal energies have a linear relationship, and the dissociation energy is correlated positively to the ionization and thermal energies, the energy per unit length is in direct proportion to the square of initial radius in different strokes of one CG lightning.« less
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