Pressure Inlet

[robin.trunk]

Hi Laurent,

yes, the getPressure gives you the total pressure. So you need to substract the dynamic pressure:
https://en.wikipedia.org/wiki/Static_pressure
This can be processed in e.g in Paraview by using the “calculator” filter.

Best
Robin

[sfraniatte]

Hi,

I am trying to set a pressure boundary condition at the inlet in the aorta3d example. However I do not find which function to use since this subject is too old now. Someone know how to do this ?

I am still a beginner and I don’t know how to find the response in Doxygen.

Thank you !

[TimBingert]

Hi sfraniatte,

you can set a pressure boundary condition on the inlet similar to how it is done on material numbers 4 and 5 on the outlets with
setInterpolatedPressureBoundary<T,DESCRIPTOR>(lattice, superGeometry, 3);

Best
Tim

[sfraniatte]

Hi Tim,

Thanks a lot for your fast respond. I did what I wanted with your help. Also, there is the example porousMedia/resolvedRock3d/ which helps.

Best regards
Sylvain

[sfraniatte]

Hello,

I figure out that I have to switch off the bouzidi boundary condition to set a pressure boundary condition. If not, the pressure at the inlet rise without stoping. Is there a way to keep the bouzidi choice ?

Thank you !

Best regards
Sylvain

[mathias]

You can apply a pressure filter as in the lid driven cavity cases using e.g. ConstRhoBGK dyamics or use the stripOffDesity methods, cf. user guide, dogygen and code examples..

[sfraniatte]

Hi Mathias,

Thank you for your time but the lid driven cavity does not use Bouzidi choice for boundaries conditions since the boundaries are all straight…

Best regards
Sylvain

[Adrian]

Whether the boundaries are straight w.r.t. to the lattice is not relevant for the choice between Bouzidi IBB and other approaches (Bouzidi just places the wall at an exact specified intersection between two cells, this also works for non-curved walls). I suspect that the boundary geometry used for Bouzidi was not set up correctly in the case where you see the broken pressure behavior. Bouzidi and pressure boundaries can definitely be used in the same simulation (e.g. this is done in both the nozzle and aorta example cases).

[Author]

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