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AC274: Smoothed Particle Hydrodynamics S. Succi. Large deformations: Grid-Free. Field: Overlap of smooth particles. Grid-free Dirac approximant. h: “ temperature ” =smooth. Moving Blobs:. FLUID: Overlap recommended!. General properties. Smoothing. Smoothing.
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AC274: Smoothed Particle Hydrodynamics S. Succi
Grid-free Dirac approximant h: “temperature”=smooth
Moving Blobs: FLUID: Overlap recommended!
1° st Golden Rule: gaussian Good analytics, but non-compact…
Gaussian Linear/Ang Mom Conservation
Smooth and compact Zero above r>2h C2-continuous: O(h^2) Insensitive to variance
Super-Gaussian W2=W4= … 0 Non-positive definite, Negative density near shocks
2°nd Golden Rule: Density inside
SPH Operators q p
Momentum-Pressure Show that: Finally:
Viscosity G-invariant Zero for rigid bodies Lin-Ang Mom conserving
SPH Algorithm • InitialConditions: 2. Density: 3. Gradients 4. Forces
SPH Algorithm 5. Move particles (MD-like) “Potential”
Applications entry Phil