vena contracta
I spent an entertaining but fruitless hour trying to find a jpeg I saved years ago. It was an early example of using 3D graphics to show anatomical details and was a chart of branches in arterial/veinal structures. As a general rule, sidebranches were at 60°, not 90° and the main flow path was non-linear (i.e., hydro-formed).
The closest I have been able to find is this:
Possibility of Atherosclerosis in an Arterial Bifurcation Model
This is a model simplified for computational purposes; reality more closely follows Victor Shauberger. 3D printed induction/exhaust will rule.