# Calculating optimal heat dissipation/air-flow out-of/into an enclosure - hole size vs number of holes

I am not sure if this is the right place to ask, but I figured it would be a physics question.

Essentially I have an enclosure that I will be using to house the components to build a computer.

I am looking to drill holes in the enclosure, above the CPU fan, so that I may either blowing hot air from the enclosure, or suck in cool air from the outside (I would assume blowing air out of the case would be best, since air rises, but thoughts on what would be better)?

I wanted to make the smallest sized hole I can, and create many of them, but bigger holes seem to allow for more transfer, but it will also make my enclosure a bit ugly, and one giant hole will also be ugly.

I am curious if there is a way to calculate the optimal size of the drill-bit I should use, if I have a certain area, of lets say 4"x4"?"

Would bigger holes, no matter what, produce better airflow, or will there be an "optimal" size for the holes that, by making the holes bigger, wont matter either at all, or much.

Thanks for any help.