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Dynamics of drag and force distributions for projectile impact in a granular medium

Massimo Pica Ciamarra·Antonio H. Lara·Andrew T. Lee·Daniel I. Goldman·Inna Vishik·Harry L. Swinney
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Abstract

Our experiments and molecular dynamics simulations on a projectile penetrating a two-dimensional granular medium reveal that the mean deceleration of the projectile is constant and proportional to the impact velocity. Thus, the time taken for a projectile to decelerate to a stop is independent of its impact velocity. The simulations show that the probability distribution function of forces on grains is time-independent during a projectile's penetration of the medium. At all times the force distribution function decreases exponentially for large forces.

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Massimo Pica Ciamarra, Antonio H. Lara, Andrew T. Lee, Daniel I. Goldman, Inna Vishik, Harry L. Swinney. 2004-04-27. Dynamics of drag and force distributions for projectile impact in a granular medium. https://doi.org/10.1103/physrevlett.92.194301

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