Numerical Modeling of Cylindrical Shell Fragmentation

Knowledge of the fragmentation of a structure during its rapid destruction is essential for ensuring the safety of people and surrounding objects. The characteristics of fragments and their space-mass distribution obtained as a result of experiments are essentially inhomogeneous. This may be due to the inhomogeneity of the structure made of real materials, which should be taken into account in calculations. The paper presents the results of numerical modeling of the problem of cylindrical shell fragmentation taking into account the probability distribution of the fracture parameter. The calculations are performed in the LOGOS software using the finite element method. Fracture of the shell is realized by separating the nodal bonds. The criterion for the onset of fracture is the exceedance of the critical value of plastic strains. The validity of the obtained results is confirmed by their agreement with the experimental data and convergence of the solution with increasing number of nodal unknowns. The influence of the fracture criterion, which is set as a material constant and as a parameter distributed according to the normal probability law, is analyzed. It is shown that the use of the probabilistic fracture criterion allows predicting the parameters of the fragmentation field, which are qualitatively consistent with the experimental data. It is established that the degree of shell discretization has a significant effect on the fragment parameters, but practically does not change the type of their mass distribution.