Scaling invariance of spherical projectile fragmentation upon highvelocity impact on a thin continuous shield
Abstract
The problem of aluminum projectile fragmentation upon highvelocity 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 threedimensional 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 weightaverage 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 scaleinvariant with respect to parameters h/D and σ{sub p}. Average masses of the largest fragments are also scaleinvariant at V > V{sub c}, but only with respect to variable parameter σ{sub p}.
 Authors:
 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; THREEDIMENSIONAL LATTICES; VELOCITY
Citation Formats
Myagkov, N. N., Email: nnmyagkov@mail.ru. Scaling invariance of spherical projectile fragmentation upon highvelocity impact on a thin continuous shield. United States: N. p., 2017.
Web. doi:10.1134/S1063776116150115.
Myagkov, N. N., Email: nnmyagkov@mail.ru. Scaling invariance of spherical projectile fragmentation upon highvelocity impact on a thin continuous shield. United States. doi:10.1134/S1063776116150115.
Myagkov, N. N., Email: nnmyagkov@mail.ru. Sun .
"Scaling invariance of spherical projectile fragmentation upon highvelocity impact on a thin continuous shield". United States.
doi:10.1134/S1063776116150115.
@article{osti_22617094,
title = {Scaling invariance of spherical projectile fragmentation upon highvelocity impact on a thin continuous shield},
author = {Myagkov, N. N., Email: nnmyagkov@mail.ru},
abstractNote = {The problem of aluminum projectile fragmentation upon highvelocity 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 threedimensional 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 weightaverage 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 scaleinvariant with respect to parameters h/D and σ{sub p}. Average masses of the largest fragments are also scaleinvariant 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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