Article details

Title: Influence of Water Layer Thickness on Fragment Velocity
Author(s): Alexandru-PetriÅŸor NiÅ£u               

Abstract: Water-filled structures are capable of providing a high level of protection against the effects of Improvised Explosive Devices, including fragments resulted from the explosion. This paper presents a simulation procedure developed to study the influence of different thicknesses of water layer on a steel ball velocity. The purpose was to investigate the residual velocities and kinetic energies after penetration, and to compare them with associated values for lethal zone, in order to evaluate the water layer thickness. To predict the initial velocity of fragments resulted from the explosion, we used the Gurney method. Impact and penetration phenomena were simulated using AUTODYN-2D hydrocode with Lagrange and Euler processors.

Keywords: ball impact, water mitigation, Gurney method, residual velocity, lethal energy, AUTODYN, Lagrange.

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