A model for fracture of explosively driven metal shells

A model for fracture of explosively driven metal shells presented in this work is based on integrating three-dimensional axisymmetric arbitrary Lagrangian–Eulerian hydrocode analyses with analyses from a newly developed fragmentation computer code MOTT. The developed model was based on the Mott’s theory of break-up of cylindrical “ring-bombs”, in which the length of the average fragment is a function of the radius and the expansion velocity of the shell at the moment of break-up, and the mechanical properties of the metal. The validation of the MOTT code fragmentation model was accomplished using existing explosive fragmentation munition arena test data. After having established the crucial parameters of the model, a new explosive fragmentation munition was designed and optimized. Upon fabrication of the developed munition, the performance of the new charge was tested in a series of small-scale experiments including flash radiography, high-speed photography, and sawdust fragment recovery. The accuracy of the MOTT code predictions is excellent.