Improved Fragmentation Algorithms for Debris Environments

摘要

In this report, we describe improved algorithms for fragmentation of targetsintercepted by hit-to-kill vehicles or high velocity fragments. The algorithms fall into two classes: (1) direct fragmentation resulting from the intercept, and (2) fragmentation of portions of the target that are directly in contact with high explosive that has itself been initiated by the intercept. The Class 1 case is further subdivided into two subclasses: (a) fragmentation of target material directly adjacent to the impact site, where the fragmentation is caused by interacting high amplitude stress waves, and (b) fragmentation of portions of the target that are undergoing large, dynamic, plastic deformation during structural response, and the stresses are limited in amplitude to the order of the yield strength. In addition, for each of the above cases, we derive algorithms for the fragment shape distributions, and also derive an algorithm for the fragment velocity distribution for the Class 2 case above, explosive fragmentation. Preliminary correlations of the above algorithms with experimental data are shown to be promising.