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DOE OSTI · 1031311

Linear diffusion into a Faraday cage.

Warne, Larry Kevin·Lin, Yau Tang·Merewether, Kimball O.·Chen, Kenneth C.
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Abstract

Linear lightning diffusion into a Faraday cage is studied. An early-time integral valid for large ratios of enclosure size to enclosure thickness and small relative permeability ({mu}/{mu}{sub 0} {le} 10) is used for this study. Existing solutions for nearby lightning impulse responses of electrically thick-wall enclosures are refined and extended to calculate the nearby lightning magnetic field (H) and time-derivative magnetic field (HDOT) inside enclosures of varying thickness caused by a decaying exponential excitation. For a direct strike scenario, the early-time integral for a worst-case line source outside the enclosure caused by an impulse is simplified and numerically integrated to give the interior H and HDOT at the location closest to the source as well as a function of distance from the source. H and HDOT enclosure response functions for decaying exponentials are considered for an enclosure wall of any thickness. Simple formulas are derived to provide a description of enclosure interior H and HDOT as well. Direct strike voltage and current bounds for a single-turn optimally-coupled loop for all three waveforms are also given.

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71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICSDIFFUSIONEXCITATIONFARADAY CUPSLIGHTNINGMAGNETIC FIELDSPERMEABILITYRESPONSE FUNCTIONSTHICKNESSWAVE FORMS

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Warne, Larry Kevin, Lin, Yau Tang, Merewether, Kimball O., Chen, Kenneth C.. 2011-11-01. Linear diffusion into a Faraday cage.. https://doi.org/10.2172/1031311

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