CFD Online Discussion Forums

CFD Online Discussion Forums (http://www.cfd-online.com/Forums/)
-   OpenFOAM (http://www.cfd-online.com/Forums/openfoam/)
-   -   isothermal compressibleTwoPhaseEulerFoam (http://www.cfd-online.com/Forums/openfoam/122615-isothermal-compressibletwophaseeulerfoam.html)

wouter August 23, 2013 04:49

isothermal compressibleTwoPhaseEulerFoam
 
Hello All,

The last three weeks I am struggling with compressibleTwoPhaseEulerFoam. I want to simulate a aerated tank with liquid flow in and out. Everything seems to work fine and then the thermodynamics crashes. The velocity of the water in the airphase at the boundary get very high because of this. If I print out the temperature in thermoI.H where the program crashes there are negative temperatures (K:confused:) so there is something wrong with the iteration.
I would like to try to run isothermal, because I am not interested in the temperature at all, but I need the expansion of the gas due to lower pressure higher up in the tank.

Can anyone tell me how to make the compressibleTwoPhaseEulerFoam isothermal?
I am using Ubuntu 12.04 64 bit
OpenFOAM 2.2.x updated and recompiled yesterday

wouter August 26, 2013 06:17

not realy the solution
 
3 Attachment(s)
Hello All,
I removed the EEqn from compressibleTwoPhaseEulerFoam but that did not solve my problem. There is really no difference at all (see pictures, first with EEqn second without). The problem is not case related and is more or less the same as in : http://www.cfd-online.com/Forums/ope...egionfoam.html but that is a completely different solver.
As you can see the arrows indicate the Uwater. These arrows are largest outside the water (in the air).
What you see:
water is coming in from the bottom left, flowing over a plate and leaving at the bottom right. In this case there is no airflow, but all over the top is atmosphere.

additional information:
The 3D form is drawn in Salome, then the patches exported as .stl files. These files are imported into HelyxOS that makes with SHM a nice mesh (attached checkMesh.txt).

Can anybody advice me how to decrease the Uwater in the air, or convince me not to worry and tell me how to get a glyph without the arrows in the air.

Any advice will be appreciated
Thanks
Wouter

wouter August 26, 2013 06:25

shortBCReport
 
1 Attachment(s)
Hello All,
With pyFoamCaseReport a short BC report for the case with compressibleTwoPhaseEulerFoam.

Thanks
Wouter


All times are GMT -4. The time now is 17:49.