This article presents a study of the sensitivities of different parameters that affect the accuracy of simulating flyer plate impact experiments. Two approaches are explored: the CTH hydrodynamic and the LS-DYNA smoothed particle hydrodynamic (SPH) codes. Simulations using these two methods are compared to experimental data from a single-stage gas gun experiment in which a copper flyer plate impacted another copper target plate. The experiment was designed to cause spall in the target plate. The numerical simulations are conducted using these combined physics models: the Mie–Grüneisen equation of state, the Johnson–Cook compressive strength model, and spall rupture. Effects of artificial viscosity, spall strength, and computational cell size are studied and discussed with the objective of improving the accuracy of these simulations. The results are verified by applying the proposed simulation approach to other flyer plate experiments.
CTH, Johnson–Cook material model, smoothed particle hydrodynamics, spall strength, SPH
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