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Title: Scaling invariance of spherical projectile fragmentation upon high-velocity impact on a thin continuous shield

Abstract

The problem of aluminum projectile fragmentation upon high-velocity impact on a thin aluminum shield is considered. A distinctive feature of this description is that the fragmentation has been numerically simulated using the complete system of equations of deformed solid mechanics by a method of smoothed particle hydrodynamics in three-dimensional setting. The transition from damage to fragmentation is analyzed and scaling relations are derived in terms of the impact velocity (V), ratio of shield thickness to projectile diameter (h/D), and ultimate strength (σ{sub p}) in the criterion of projectile and shield fracture. Analysis shows that the critical impact velocity V{sub c} (separating the damage and fragmentation regions) is a power function of σ{sub p} and h/D. In the supercritical region (V > V{sub c}), the weight-average fragment mass asymptotically tends to a power function of the impact velocity with exponent independent of h/D and σ{sub p}. Mean cumulative fragment mass distributions at the critical point are scale-invariant with respect to parameters h/D and σ{sub p}. Average masses of the largest fragments are also scale-invariant at V > V{sub c}, but only with respect to variable parameter σ{sub p}.

Authors:
 [1]
  1. Russian Academy of Sciences, Institute of Applied Mechanics (Russian Federation)
Publication Date:
OSTI Identifier:
22617094
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Experimental and Theoretical Physics; Journal Volume: 124; Journal Issue: 1; Other Information: Copyright (c) 2017 Pleiades Publishing, Inc.; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; ALUMINIUM; EQUATIONS; FRACTURES; FRAGMENTATION; HYDRODYNAMICS; MASS; MASS DISTRIBUTION; PROJECTILES; SHIELDS; SIMULATION; SOLIDS; SPHERICAL CONFIGURATION; THICKNESS; THREE-DIMENSIONAL LATTICES; VELOCITY

Citation Formats

Myagkov, N. N., E-mail: nn-myagkov@mail.ru. Scaling invariance of spherical projectile fragmentation upon high-velocity impact on a thin continuous shield. United States: N. p., 2017. Web. doi:10.1134/S1063776116150115.
Myagkov, N. N., E-mail: nn-myagkov@mail.ru. Scaling invariance of spherical projectile fragmentation upon high-velocity impact on a thin continuous shield. United States. doi:10.1134/S1063776116150115.
Myagkov, N. N., E-mail: nn-myagkov@mail.ru. Sun . "Scaling invariance of spherical projectile fragmentation upon high-velocity impact on a thin continuous shield". United States. doi:10.1134/S1063776116150115.
@article{osti_22617094,
title = {Scaling invariance of spherical projectile fragmentation upon high-velocity impact on a thin continuous shield},
author = {Myagkov, N. N., E-mail: nn-myagkov@mail.ru},
abstractNote = {The problem of aluminum projectile fragmentation upon high-velocity impact on a thin aluminum shield is considered. A distinctive feature of this description is that the fragmentation has been numerically simulated using the complete system of equations of deformed solid mechanics by a method of smoothed particle hydrodynamics in three-dimensional setting. The transition from damage to fragmentation is analyzed and scaling relations are derived in terms of the impact velocity (V), ratio of shield thickness to projectile diameter (h/D), and ultimate strength (σ{sub p}) in the criterion of projectile and shield fracture. Analysis shows that the critical impact velocity V{sub c} (separating the damage and fragmentation regions) is a power function of σ{sub p} and h/D. In the supercritical region (V > V{sub c}), the weight-average fragment mass asymptotically tends to a power function of the impact velocity with exponent independent of h/D and σ{sub p}. Mean cumulative fragment mass distributions at the critical point are scale-invariant with respect to parameters h/D and σ{sub p}. Average masses of the largest fragments are also scale-invariant at V > V{sub c}, but only with respect to variable parameter σ{sub p}.},
doi = {10.1134/S1063776116150115},
journal = {Journal of Experimental and Theoretical Physics},
number = 1,
volume = 124,
place = {United States},
year = {Sun Jan 15 00:00:00 EST 2017},
month = {Sun Jan 15 00:00:00 EST 2017}
}
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