code_saturne User's Forum

Hello,

I do a simulation of a fluid domain that contains three inlets and three outlets, in the three inlets I impose a identic velocity profile (for three inlets) but when I check, after simulation, at each inlet the rate flow I observe that there is a difference between the rate flow in three inlets against in outlets I have the same rate flow?!

is that there is an explanation please for the origine of the difference of rate flow at the inlets although the velocity profile imposed is the same?

Thanks a lot

Hello,

Do the three inlets of your flow domain have the same surface area and are they in the same plane, e.g. the x-z plane?

If the surface area is different for each inlet and they are all in the same plane, the mass flow rates will not be the same.

If the inlets have the same surface area but are aligned differently relative to your flow domain, e.g. one inlet is in the x-z plane and the other two inlets are in the y-z plane, you will need to ensure that the velocity profile imposed is aligned correctly and uses the appropriate velocity component, e.g. the Vy component for the x-z plane or the Vx component for the y-z plane.

Brian.

Thanks Brian for your answer,

The inlets are same surfaces and all inlets are in same plane and same level !

I imposed two component of velocity profile (Z and X)

How are you specifying the inlet velocity profiles, via the GUI or a user subroutine?

Brian.

I used a subroutine to specify the velocity profile (The difference between rate flow is of ordre of 10-2)

Ok. Can you put up the 'listing' file, the user subroutine for specifying the profile and some images of your flow domain with the inlet and outlet boundaries.

Thanks Brian, it's OK now !

The problem apparently came from the mesh, I regenerated the mesh and now I have equal flow rate

Thanks

Ok.