Transcript SPH modeling

Example 3: Smoothed particle hydrodynamics
(SPH) modeling for an impact problem
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EXAMPLE 3
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SPH modeling is available from Abaqus version 6.11.
 Smoothed particle hydrodynamics (SPH)
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A meshless Lagrangian technique, based on interpolation theory and smoothing kernel functions.
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Fluid (impactor) is represented as a set of discrete interacting particles, which are independent
from Lagrangian elements.
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No mesh distortion of the fluid.
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No solution domain to define a spatial mesh for fluid.
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The method provide more accurate results than Lagrangian or coupled Eulerian-Lagrangian
analyses when the deformation is too severe.
 Application of SPH modeling
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Effective for applications involving extreme deformation
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In stead of the coupled Eulerian-Lagrangian modeling, SPH modeling can be used to reduce
computational cost.
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Example problems: Fluid sloshing, wave engineering, ballistics, spraying (as in paint spraying), gas
flow, and obliteration and fragmentation followed by secondary impacts.
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Direct impact problem
A soft body (5kg) with 50 m/sec impacts
on the aluminum plate.
 Aluminum plate
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Dimensions: 1m× 1m× 0.002m
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Material type: Linearly elastic behavior with
isotropic hardening
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Element : Shell elements (S4R)
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Mesh size: 0.01m-0.05m
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Boundary condition: Four edges are fully
constrained.
 Soft body impactor
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Shape: cylinder with two hemispherical caps
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Dimensions: 0.32 in length × 0.16 m in a
diameter
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Length/ diameter = 2
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Material: Gelatin
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Initial bird mass: 5 kg
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Magnitude of initial velocity: VZ = -50 m/s
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SPH particle elements (PC3D)
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Target structure
• Model type: Shell model
• Shape: Square plate
• Dimensions: 1m× 1m
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Impactor
• Model type: Solid model
• Shape: Cylinder with hemispherical caps
• Dimensions: 0.16 m in a diameter × 0.32 m in length
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Coordinate
(0.5, 0.5, 0.01)
Coordinate
(0,0,0)
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The part with C3D8R,
C3D6, or C3D4 elements
or a combination of these
elements can be
converted to SPH particle
elements (1-node PC3D
element ).
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Animation
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Animation
Target: 0 <X < 0.8
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SPH modeling is available from Abaqus version 6.11.
 ABAQUS 6.12 documentation: Abaqus Analysis User's Manual
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“Smoothed particle hydrodynamic analyses,” Section 15.1
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“Equations of state,” Section 25.2
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“Section controls,” Section 27.1.4
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“Particle elements,” Section 28.5
 ABAQUS 6.12 documentation: Abaqus Example Problems Manual
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“Impact of a water-filled bottle,” Section 2.3.2
 Journals/proceedings
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Heimbs, S. 2011. “Computational Methods for Bird Strike Simulations: a Review,” Comput. &
Struct., 89(23-24):2093-2112.
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McCallum, S.C. and C. Constantinou. 2005. “The Influence of Bird-shape in Bird-strike Analysis,”
presented at the 5th European LS-DYNA Users Conference, May 25-26, 2005.
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Nanami, N. and O.O. Ochoa. 2012. “Computational Assessment of Bird Strike on Hybrid Composite
Wind Turbine Blade,” In: Proceedings of the American Society for Composites 27th Annual
Technical Conference, Arlington, Texas, USA, October 1-3, 2012.
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