[kirzoaktrt]

Hello.

I am trying to set up a simple 2D case for simulating a non-isothermal bubble column that I wish to solve with compressibleInterFoam. I uploaded the case here: https://drive.google.com/file/d/0B_V...ew?usp=sharing

The geometry can be seen in the attachment.

My current BC's are:

alpha.water: walls-zeroGradient; frontAndBack-empty; inlet-fixedValue,uniform 0; outlet-inletOutlet,inletValue 0,value 0;
p: walls-calculated,uniform 1e5; frontAndBack-empty; inlet-zeroGradient; outlet-fixedValue,uniform 0;
p_rgh: internalField-uniform 1e5; walls-zeroGradient; frontAndBack-empty; inlet-fixedValue,value 2e5; outlet-fixedValue,uniform 1e5;
T: zeroGradient on walls, uniform 300 on inlet, setFields sets the water temp to 600 (can this be a problem?).
U: walls-fixedValue,uniform (0 0 0); frontAndBack-empty; inlet-fixedValue,uniform (0.1 0 0); outlet-pressureInletOutletVelocity,value uniform (0 0 0)

The simulation crashes with the following error:

--> FOAM FATAL IO ERROR:
wrong token type - expected Scalar, found on line 0 the word 'nan'

file: C:/cygwin64/home/pal/OpenFOAM/pal-2.3.x/run/twophase_runs/2/system/data.solverPerformance.p_rgh at line 0.

The Courant number is also 0, and obviously I get nan's for all fields in the first iteration.

I am fairly new to OpenFoam, so I suspect that I set up the boundary conditions incorrectly. Apart from the BC's and setFields params, the case is entirely based upon the depthCharge2D tutorial case. The transport and thermodynamics properties are the same as in the tutorial case.

I would really appreciate any kind of guidance on how to set these BC's correctly. Thanks.

[olivierG]

hello,

You use p value at outlet = 0. This is absolute pressure ! Use 1e5 like with p_rgh.

regards,
olivier

[kirzoaktrt]

Thanks. It does work now.

The results seem weird though. The bubble I get seems to be wetting the walls where the inlet is. The BC on the wall is zeroGradient for alpha. I wonder if there is a proper BC that makes sure that no air touches the walls (i.e., make the wall repellent of one phase). I tried fixedValue uniform 1 at the wall (saying that at the wall, there is always pure water), but that case did not converge.