Dynamic fragmentation in impacts: hydrocode simulation of laboratory impacts

A continuum damage model of dynamic fragmentation originally proposed by Grady and Kipp is generalized to two and higher dimensions. Algorithms are developed that permit efficient computer implementation of this model in the context of a Lagrangian hydrocode and compare the code predictions to an extensive suite of laboratory impact fragmentation experiments. Both the largest fragment size and many details of the fragment size-number distribution are faithfully reproduced by the code, including the previously enigmatic segmentation of the cumulative size-number distributions. The model of failure may be different for laboratory size scales and geologically interesting problems such as multikilometer-scale impact cratering or asteroid fragmentation, making it imperative to use physical modeling rather than empirical scaling laws to address fragmentation at large size scales. -from Authors