Hi EVERYBODY,

I have a problem with a WARNING, if any of you could help me! Well, the warning is:

"Both outflow and pressure boundaries are present in the domain. This is an incompatibility and solution cannot proceed until this is fixed."

My case is a air flow in direction (-1,0,0) with a water flow in direction (0,-1,0). Both are separeted with walls between them. Each of them has one outlet. The air has a Pressure outlet and the water an Outflow Boundary Condition.

If someboby know how to help me or know some way to treat that kind of case,please, let me know it.

THANKS A LOT

BYE AND PEACE!

JORDI

Why are you using Outflow Condition? Can't both of them be pressure outlets or outlet vents? Just a thought.

I'm using outflow because I don't know anything about the outlet. In the pressure outlet I have to put the gauge pressure and I don't know it. The outlet vent I don't know how it works. If U can help me, I'll be so grateful.

The thing is I have to put some outlet BC what don't have any influence in the flow because my Control Volum is (15mm height - 6mm weihgt - 30mm depth)but all the radiatot is bigger than that.

If you could give me some tip or how to initialize the case or how to simulate (like what steps I have to lead) it will be so useful.

Thanks a lot for replay me SOWAJANYA.

And where r you? your name is wird for me but it's nice.

BYE and THANKS

PEACE

JORDI

[ershad]

hi
I am simulating a membrane bio-reactor. My reactor has 2 main volumes (Attached file). I subtracted smaller volume from the other, but I retained the subtracted volume.
I have defined 3 boundary conditions as follow:

1. Velocity Inlet (flow of air) : the lower face of smaller volume
2. Pressure outlet: the upper face of bigger volume: it is open to atmosphere.
3. ???I don't know how to define the boundary condition of the upper face of smaller volume. In reality the smaller volume is open from top and the air rise up in the smaller volume and goes out from top of it and enters the bigger volume, At initial, the reactor is full of water and its volume fraction is 1.
I have tried some boundary conditions for the upper face of smaller volume(face2), but I encountered ERRORS as follow:

1. OUTFLOW: "Warning both outflow and and pressure boundaries are present in the domain. This is an incompatibility and solution cannot proceed until this is fixed."

2. INTERIOR: "Error: Cannot change face2 to interior because there is only one adjacent cell thread."

3. INTERNAL: "Error: Cannot change face2 to interior because there is only one adjacent cell thread."

What can I define the boundary condition of that face?
Sincerely yours,
Ershad