This topic is totally alien to me, so I may be asking something very obvious.
I am designing a cooling system. In the bulk of aluminum, I drill 3mm holes and then I connect them one to another to create a long path for the stream.
The question is now, how long can this maze be? What I am trying to figure out to answer this question is first of all, what pressure is required to drive water into this pipeline. And to determine that, I believe, somewhere should be a coefficient of friction between water and aluminum. Though I can't seem to find a useful chart, it's all about solid bodies friction. Is it because the coefficient might in fact depend on the pipe diameter?