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Smoothed Particles Hydrodynamics
(Courtesy H.Bung, CEA Saclay)
• Application domain: impact of a relatively soft body
(~fluid) onto a structure, typically with fragmentation:
– Aeronautics: bird strike
– Nuclear: various applications (e.g. corium slug impact)
– …
• Goal: verify behaviour of the structure (not so much of the
impacting body)
• Advantages: it allows to overcome the limitations of
classical FE-based methods in problems where a constant
mesh topology becomes a serious drawback
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Why a Particle-Based Method?
• FE Lagrangian formulation: the mesh follows the material
∪ Well adapted for solid behaviour
∪ Relatively easy treatment of B.C.s
∪ Need to model only the real domain
∩ However: if deformations exceed a certain value,
remeshing becomes necessary, else calculation stops
• FE Eulerian formulation: the mesh is fixed
∪ Well adapted for fluid behaviour
∪ No mesh distortions
∩ More difficult treatment of B.C.s (e.g. free surface tracking)
∩ In certain problems (e.g. rotating bodies) need to model more than
the real domain
∩ Longer and less accurate calculations due to transport terms
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