1. Fluid Simulation for Graphics
Minor project under guidance of Prof. P. Kalra
Abhinav Golas
Akram Khan

2. Outline Fluid animation Work done What it is What it is not Uses
Models
Work done
Work done earlier
Current focus
Future work

3. Fluid animation
Modeling and Rendering fluids in a manner which is visually appealing
NOT a numerically complete simulation
Model is scenario dependent – computationally expensive

4. Uses
Movies! – Titanic, Ice Age, LOTR etc.
Games! – All!

5. The Navier Stokes Equation
Governs all fluid behaviour
PDE – no closed form
Solutions only through numerical simulation
Issues of numerical errors, and stability
Computationally very expensive
Boundary conditions and level of discretisation important

6. Models Heightfield generation CFD – Computational Fluid Dynamics
For showing ocean surfaces
Used when field of view is large
Doesn’t directly solve Navier Stokes – uses generalised solutions
CFD – Computational Fluid Dynamics
Iteratively solve NS eqns for a 3D grid
Surface reconstruction – recent work
Fixed grid positions – Eulerian approach

7. Models Smoothed Particle Hydrodynamics
System as collection of fluid particles
Governed by NS eqns
Surface reconstruction

8. Surface reconstruction
Problem:
Given a set of particles, need to generate a smooth wrapping surface
Approach (currently used)
Level sets
Hybrid approach (level sets + curvature measures)

9. Work done earlier Literature review to find current state-of-the-art
Issues in simulation of different types of fluids:
Viscous
Snow
Fire

10. Current focus Getting implementations of the state-of-the-art methods
Heightfields
CFD
SPH
References
SIGGRAPH 2004 course on realistic nature animation
SIGGRAPH 2006 course on fluid simulation

11. Progress Some heightfields implemented Work on CFD
Gerstner waves (video on site)
Statistics based ocean waves
Velocity field based animation
Choppy waves (currently underway)
Work on CFD
Making an implementation

12. Some results

13. Some results

14. Future work Complete implementations of these fluid simulation methods
Identify areas for further improvement/research
Spray/Foam
Bubbles