problem with Boundary Conditions (including pressureInletUniformVelocity)
 

Hello everyone. I am rather new to the OpenFOAM software and despite reading descriptions of some Boundary Conditions (BC), I’d like to get some practical information from the advanced users (concerning BC). I’m investigating blood flow in the human blood vessel and I hesitate whether BC I impose are appropriate. I tested several combinations (let’s assume only inlet called My_Inlet and outlet called My_Outlet):

https://imgur.com/a/T34tJ

https://imgur.com/a/T34tJ

P.S. Sorry, I don't know how can I upload image here - tried with specifing link in the 'Insert Image', but image doesn't show up. Problem is outlined in the image on imgur (check link above) or as attached PDF file.

I know that when setting velocity/flow rate on the inlet, outlet should have pressure prescribed and vice versa. That’s why I hope all presented cases above are somehow correct (I’m not talking about values, just types of BC). I wanted to confirm that by asking you, advanced users. Moreover, I encountered a BC called pressureInletUniformVelocity and despite reading its description, I don’t know how to interpret it. In the U-file for My_Inlet I’m setting this BC and giving the pressure value? Then what should be in the p-file for My_Inlet – zeroGradient? And what about the My_Outlet? Does U-file should have zeroGradient, while p-file fixedValue?
I hope I didn’t make my questions sound complex and I’d be really grateful if someone could provide me some tips/information. Moreover, which BC pair is better: velocity-pressure or pressureInletUniformVelocity-pressure?