I have (tried) to work with OpenFOAM in the past, and I would very much not recommend it for someone who doesn't already have an intimate knowledge of CFD. It has a very steep learning curve and no GUI whatsoever anymore. It may be powerful and free, but it is not appropriate for OP's needs. As far as I can tell it was formerly a commercial code that was open-sourced, but they keep it as non-intuitive as possible to try to sell people on the $2000 dollar training courses they put on.

The Internet is still "cool" because it has that lawless wild west sort of feel to it. The useless bureaucracy that is the UN would only make it un-fun. Sure it may be "dangerous" if you dont know what you're doing, but why would anyone wander around the wild west if they didnt know what they were doing.