Grid Adaptation for NonLinear Dynamics

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Grid Adaptation for Non-Linear Dynamics
Sudeep K. Lahiri and Prof. Jaime Peraire

• Engineering problems like Crash Rapid phenomena,
  small time scales.
• Non-linear continuum mechanics (large
  deformations, non-linear material properties)
• Requires efficient algorithms for large system
  dynamics, typically explicit schemes
• Variational time integrators Better
  conservational properties, better for long
  computation
• Mesh adaptation for local resolution

Industry research, using DYNA3D
A 50 ton train car colliding with a rigid wall at
60mph
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Variational Integrators and Finite Elements
Fractional Time Step Method, performs better for
incompressible material behavior and conserves
momentum exactly
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Variational Mesh Adaptation
Swapping
Node Movement (reference configuration)
Edge-splitting
Edge-collapsing
Variational formulation for various mesh
adaptation algorithms are being developed with
mechanisms like diagonal-swapping, node movement,
edge-splitting and collapsing of edges.