Numerical Evaluation of a Multiscale Friction Model

A set of experiments designed to produce dry sliding of metal-on-metal resulting in normal pressures up to 10 GPa and sliding velocities up to 400 m/s are simulated numerically for the purpose of evaluating a multiscale friction model. These experiments involve the impact of a cylindrical copper flyer onto a composite cylindrical target composed of an aluminum inner core and a stainless steel circumferential confinement. The primary diagnostic in these experiments is a measurement of free-surface velocity. The numerical simulation is conducted using the Los Alamos continuum mechanics code FLAG. The primary metric of evaluation is a comparison of predicted free-surface velocities to those measured. The importance of accounting for friction in the simulation of these experiments is clearly demonstrated. It is shown that the FLAG implementation of the multiscale friciton model provides capabilities that are essential in the modeling of dry sliding friction.