Numerical simulation and validation of distributed impact events

An underwater explosion (UNDEX) validation methodology was presented in O’Daniel et al. (2002, Int. J. Impact. Eng. 27, 919), describing a process where precision impact tests were used to generate a response equivalent to the underwater structural response of a flat panel subjected to a blast wave. A critical part of the methodology was to validate the code LS-DYNA3D (LSTC 936 (1995)) for the explicit finite element analyses of the short duration elastic responses of aluminum and composite panels subjected to low velocity, line and distributed impact loadings. A line impact was used as a base to perform preliminary tests of the precision impact test system, and the distributed impact configuration was necessary to generate a response similar to an underwater blast wave loading. Once validated for that range of structural response under impact loading conditions, LS-DYNA3D could then be used to predict impact tests to find responses that were equivalent to the UNDEX response of the target. This paper presents a detailed description of the precision impact events, and a comprehensive coverage of the validation of LS-DYNA3D for those impact events. O’Daniel et al. [1] provides an explanation of the equivalence between impact and UNDEX, as well as the overall methodology.