Real-time fluid simulation techniques

Question

What techniques are used for the real-time simulation of fluids such as water, for example in videogames?

In particular, I am looking for a project-idea for an (unfortunately rather short) physics project at Uni, so the simpler the better (if there is any such thing as "simple" in fluid-simulations...)

Ake

Try searching stackoverflow for questions involving "particle animation". – Schapira

See here: scholar.google.co.uk/… – Hartill

(And for what it's worth, I don't mean the Google link facetiously - Google Scholar is exactly where I'd start with this sort of thing.) – Hartill

I usually don't use Google Scholar, simply because many of the papers it links to cost money without even providing a 'look inside' feature. – Ake

As a tip, find the names using Google Scholar, then search the web for the PDFs - often turns up trumps because the authors will generally upload their papers on their personal websites. – Hartill

(But yes, I've sometimes found that frustrating since leaving university - I'm very strongly of the opinion that all research journals should be open access. The trouble is how you fund it, of course.) – Hartill

@Ake There are many similar questions on SO, so have a look. I have answered two that might help here and here. And see the "Related" questions in the sidebar for example. – Incisive

Answer 1

AFAIK the most popular method to simulate fluids in real-time is the SPH method:

• Smoothed-particle hydrodynamics - Wikipedia, the free encyclopedia

It's implemented in Bullet, PhysX, and Fluids:

Fluids v.3 is a large-scale, open source fluid simulator for the CPU and GPU using the smooth particle hydrodynamics method. Fluids is capable of efficiently simulating up to 8 million particles on the GPU (on 1500 MB of ram).

Some other helpful sources:

• GPU Gems - Chapter 38. Fast Fluid Dynamics Simulation on the GPU
• Open source 3D SPH solver - Math and Physics - GameDev.net
• SPHYSICS Home Page - SPHYSICS

Jolandajolanta

Oh, I forget to post another good link about FLUIDS v2 project. I updated my answer. – Jolandajolanta

One thing to note about SPH (which is also mentioned on the FLUIDS site) is that it is very hard to get good parameters in practice, and you also need pretty small time steps. The other popular method next to SPH is grid-based methods, which allow for much larger time steps (see GPU Gems 3: http.developer.nvidia.com/GPUGems3/gpugems3_ch30.html). The CUDA SDK also contains a sample of this for simulating smoke. – Stagy