code_saturne User's Forum

Hello,
 
I am just interested in knowing the pressure (total and fluctuation) around a profile put into a flow but I do not really know the variable I need to use to have it...
I was adviced to use the variable RTP which is the "increment" pressure but we do not really understand what it represents concretely... Is it the pressure variation between the time now and the last time step or the variation of pressure compared to the total pressure? or maybe, it exists a more adapted variable to my problem?
Thank you for your future and precious answer.
Best regards,
 
Frédérique Chevalier

Hello,

As the pressure in an incompressible flow is only defined to withing a constant, RTP(IPR) is the pressure around your profile, plus an arbitrary constant (which you may adjust by choosing the reference outlet pressure value).

When post processing, you have both this and a "total" pressure.

The pressure solved is actually P* (that is P + rho.g.z if I am not mistaken), which is important to know if you are working on natural convection or atmospheric flows, but is not an issue if you are interested in a flow around a profile.

Best regards,

  Yvan