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Pretorius, David

Publications and source records attributed to Pretorius, David.

Lightning Burnthrough to Containment Breach of 55-Gallon TRU Waste Drums

We investigated by arc-plasma heating the feasibility of attributing inherent lightning protection to 55-gallon DOT 7A, Type A, open head carbon steel drums made of 1.5 millimeter painted carbon steel, designed to protect Department of Energy transuranic nuclear waste. The Sandia Lightning Simulator transferred continuing current in 300 ampere (A), 400 A, and 500 A tests to achieve a 350 coulomb charge transfer and simulate cloud-to-ground lightning attachment to test coupons and 9 drums. A tungsten electrode was placed 0.75 inch from the drums. High-speed photography was recorded to observe the exterior containment breach, or "first light," seen on camera when burnthrough opened a hole in the containment. Sheet metal burnthrough occurred between 18 and 71 coulombs in lid and rolling hoop tests, but 12-gauge closure ring tests did not result in burnthrough, which suggests this feature may provide an inherent air terminal protective feature.

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗

LANL Lightning Flash Time Duration Ground Truth

Video cameras were used to record cloud-to-ground (CG) lightning flash events on or near Los Alamos National Laboratory (LANL) over 3 days in August, 2018. Custom scripting software was created to automatically trigger camera recording off National Lightning Data Network (NLDN) streamed reporting of CG lightning within 12 miles of LANL. Cameras were sited near meteorology towers at LANL and 4k video captures were manually reviewed to extract still sequence images from 9 identified CG flashes. A camera frame rate of 30 fps was used to estimate time durations of 33-200 milliseconds over this natural lightning dataset.

58 GEOSCIENCES↗