A good 2D fluid simulation (works for air too) would be nice--see link below.
A very clear explanation about solution and stability is here:
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I am willing to pay 100$ for a robust well documented plugin using this fluid dynamics model to be made public to all C3 users. I am just intellectually curious and would like to see it done and available to everyone. I can only pay one person 100$ for doing it so please contact me before you start and I will post here that there is someone working on it.
It needs to work in C3 using the latest engine.