Particle velocity non-uniformity and steady-wave propagation
A constitutive equation grounded in dislocation dynamics is shown to be incapable of describing the propagation of shock fronts in solids. Shock wave experiments and theoretical investigations motivate an additional collective mechanism of stress relaxation that should be incorporated into the model through the standard deviation of the particle velocity, which is found to be proportional to the strain rate. In this case, the governing equation system results in a second-order differential equation of square non-linearity. Solution to this equation and calculations for D16 aluminum alloy show a more precise coincidence of the theoretical and experimental velocity profiles.
KeywordsParticle velocity Meso–macro momentum exchange Shock waves Dislocation dynamics
The author thanks A.K. Divakov and Yu. A. Petrov for the velocity profiles used.
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