Comparison of the Fragmentation Zone Propagation model issued from molecular dynamics simulations and momentum mass measurements in microjetting experiments

The Fragmentation Zone Propagation (FZP) model proposes an interpretation of the fragmentation of ejected sheets of liquid metal issued from shock-loaded surfaces (microjetting). It results from the analysis of very large-scale Molecular Dynamics (MD) simulations of the phenomenon. One of the output of this model is the calculation of the surface mass distribution versus speed. We tested its relevance by performing shock-induced experiments of matter ejection on grooved tin samples. The grooved were designed to obtain a variety of mass distribution. The calculation compared very well with the measurements, using a single fitting parameter for all the experiments. This conforts that the FZP model, although issued from simulations performed at much smaller length scales than those of experiments, is of very helpful to interpret the experiments. In particular, it describes very well the head of the ejecta cloud where the traditional expontial model fails.