Fragmentation of a Titanium Alloy Shell in Expansion: From Experiment to Simulation

From first experiments in fragmentation of shells by Mott to nowadays, two challenges still persist: obtain quantitative observation during experiments and succeed to do simulations which reproduce experimental data and fragmentation. We propose in this paper to illustrate these two challenges using the expansion of a spherical shell of titanium alloy (Ti – 6 Al – 4 V). We will describe first the experimental setup, focusing on the different diagnosis used, in particular PDV grid and laser imaging. The junction of both measurements allowed us to generate a 3D reconstruction of the expansion. Then we will describe the 2D numerical simulation which allows us to rebuild the results from the PDV grid and is used to initiate 3D analysis leading to the generation of fragments. The comparison between experimental results and numerical ones will be presented and commented.