A closed form, energy-based theory of dynamic fragmentation

A statistical fragmentation model is presented, which predicts the average size and distribution in sizes of fragments emanating from an explosively driven, naturally fragmenting cylinder. The model builds on the energy-based fracture model of [Kipp and Grady, J. Mechanical Phys. Solids 33, 399 (1985)] by closing the calculation of average fragment size with the introduction of a crack velocity, which determines the time required for a newly initiated fracture to proceed to completion. Fracture energy is accounted for in the solution, resulting in a bimodal distribution function. Calculations are presented in comparison to experimental data for explosively driven metal sleeves and impact fragmentation. From comparison to existing fragmentation models and test data, we demonstrate the feasibility of the proposed approach.