Boundary Layers Rules of Thumb

I am a fairly new user to the Floworks add-in and have found myself with some questions that I am assuming others have.

I figured a "Rule of Thumb" for boundary layers that people have learned along the way would be a great resource.

I am looking for the answer of the following:

What are the rules of thumb as far as dictating outlet pressures in a tubing system with fluid flow?

When would I use Total vs. Environmental vs. Static pressure for the outlet boundary conditions?

Post up if you have an answer OR if you have a new questions.

Thanks,

Dave

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