Modeling the response of weapon system shipping and storage containers to lightning

The Defense Nuclear Agency (DNA), as part of its ongoing weapon safety assessments, is evaluating a number of electrical environments that might surround certain weapon systems in their day-to-day operations and maintenance activities. This paper describes one of the modeling approaches that was used to analyze abnormal electrical environments that might surround some weapon components. The paper first describes the modeling problem and the alternative approaches that were available for modeling objects and the intruding environments. PSPICE, a readily available and widely used circuit simulator code, was chosen to bound the responses of several rather complex structures and objects to both direct and indirect lightning strikes. This paper describes how PSPICE was used to model the lightning response of one of the objects, a shipping and storage container used to transport weapon components to and from operational sites. The paper describes the modeling process in detail along with the simplifying assumptions and presents the modeling results. Finally, the paper compares the modeling results with electromagnetic test data gathered on an actual shipping and storage container