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Old   August 3, 2010, 09:30
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  #121
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Bernhard Gschaider
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Quote:
Originally Posted by rob3rt View Post
Hi Eveyone,

I want to implement a transient boundary conditions, hence I need boundaryData file under constant. However,the problem is the property that I want to vary with time is dimensionedScalar (No_Read in CreateFields.H) instead of volScalarField. What can I do to implement this? I have tried to put this in the solver, but doesn't work.

if (runTime.value() > 500)
{
Q = 600;
}
else
{
Q = 0;
}

Suggestions will be very much appreciated.

Thanks in advance.

Robert
I think there is no need to do anything in the solver. Setting the right boundary conditions should be sufficient. If it is a value you want to fix then have a look at timeVaryingUniform (that comes with OpenFOAM) else (gradients, mixed) have a look at groovyBC. There an expression like "(time>500) ? 600 : 0" should get you where you want

Bernhard
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Old   September 1, 2010, 20:10
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  #122
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Abdel
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Dear Foamers,

i'm using sonicFoam and i have to use a pressure inlet time depended boundary condition (i have files (total pressure, temperature, velocity) from real test).

I am an OpenFOAM beginner can you help me please.

Best regards.
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Old   September 2, 2010, 03:09
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  #123
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Tobias Holzinger
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Hi Abdel,

try the timeVaryingUniformFixedValue BC...
input is a file like (ti pi ):

Code:
(
(0 100000)
(0.001 99880)
(0.002 120000)
...
)
Greez
Tobias
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Old   September 2, 2010, 17:37
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  #124
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Abdel
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Hi!

thanks for your response, now i've another problem :

--> FOAM FATAL IO ERROR:
keyword internalField is undefined in dictionary "/home/moumen/tfe/axis/test64/0/p"

how i shoud define my internalField.

Best regards


Quote:
Originally Posted by woody View Post
Hi Abdel,

try the timeVaryingUniformFixedValue BC...
input is a file like (ti pi ):

Code:
(
(0 100000)
(0.001 99880)
(0.002 120000)
...
)
Greez
Tobias
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Old   September 3, 2010, 04:12
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  #125
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Tobias Holzinger
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Hi Abdel,

sorry but this question can't be serious. I would recommend reading the manual, doing some tutorials, and afterwards implementing your case...

Good Luck

Tobi
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Old   October 4, 2010, 04:45
Default groovyBc compilation error
  #126
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Yashar Afarin
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hello,
i am using OpenFOAM-1.6.x on Fedora12 (64 bit).
i want to install "groovyBC" and if i compile it with "wmake libso" in the sources this error would be appear:
linux64GccDPOpt/options:14: *** missing separator. Stop.
wmake error: file 'Make/linux64GccDPOpt/objectFiles' could not be created


i wolud appreciate it if someone help me.
thanks
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Old   August 30, 2011, 05:39
Default Problem with transient boundary condition
  #127
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Muhammad Umer Ijaz Chaudrey
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Hi everyone,

i am a new user of openFoam. using version 2.0

I am trying to implement timeVaryingUniformFixedValue boundary condition for outlet in which Pressure varies with time at a face. I read the initial discussion and tried to implement it. But i am getting this error when i try to run simpleFoam. Can kindly anyone please guide me and help me in this. Thanks

--> FOAM FATAL IO ERROR:
keyword outOfBounds is undefined in dictionary "/home/asml/Umer/openfoam200/Work/test/testtransient/0/p::boundaryField::WALL_c0_f5"

file: /home/asml/Umer/openfoam200/Work/test/testtransient/0/p::boundaryField::WALL_c0_f5 from line 24 to line 26.

From function dictionary::lookupEntry(const word&, bool, bool) const
in file db/dictionary/dictionary.C at line 400.

Kind Regards,
Umer
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Old   August 30, 2011, 06:46
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  #128
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Tobias Holzinger
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Hey Umer!

RTFM!

outOFBounds warn/clamp/stop;

in your 0/p Field should help!

Regards!

Tobias
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Old   August 30, 2011, 08:03
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  #129
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Muhammad Umer Ijaz Chaudrey
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Dear Tobias Holzinger,

Thanks for your reply and feedback. This is how my 0/p file looks. Tried clamp/repeat/stop with outOFBounds. But I still get the same error.

This is how my boundary looks in 0/p file. Rest all others are fine, because if i run with a fixed uniform value the solution runs.

"WALL_c0_f5
{
type timeVaryingUniformFixedValue;
timeDataFileName outlet.dat;
value uniform 82700;
outOFBounds stop; //clamp/repeat
}

The outlet.dat text file is in the form of:
(t0 p0
t1 p1..
....
tN pN
)

But when i try to run simpleFoam, i get the same error.

I don't still understand how to fix it and run my solution. Is there anyother way to implement this too? But this seems simple and its not working for me. Please guide me where I can be wrong. Thanks

Kind Regards,
Umer
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Old   August 30, 2011, 08:22
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Dear Tobias,

I think I was making a blunder in spellings as pointed in another thread. So I will fix it and check again. Thank you again for your help in identification of problem. Appreciate that.

Kind Regards,

Umer
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Old   September 1, 2011, 03:23
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  #131
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Tobias Holzinger
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Looking up the code I don't see stop...

only clamp, warn, repeat and error seem to work...

Regards Tobias
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Old   September 1, 2011, 08:06
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  #132
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Muhammad Umer Ijaz Chaudrey
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Dear Tobias,

Yes, got it, it was a small mistake. Thanks for the help.

Regards,

Umer
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Old   November 30, 2011, 12:06
Default Has anybody ever used cyclic boundary conditions in sonicFoam?
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Has anybody ever used cyclic boundary conditions in sonicFoam?
I have used them in mhdFoam ( a solver for magnetohydrodynamics (MHD): incompressible, laminar flow of a conducting fluid under the influence of a magnetic field.). As far as this solver concerned, everything worked well! Nevertheless, when I tried to use cyclic boundary conditions in sonicFoam I had errors!I don`t know how can I write the cyclic boundary conditions for the pressure. I have a 2-D cavity.

For example in sonicFoam/laminar/forwardstep/0/p:
outlet
{
type waveTransmissive;
field p;
phi phi;
rho rho;
psi psi;
gamma 1.4;
fieldInf 1;
lInf 3;
value uniform 1;
}

when I want to declare it as cyclic , I can write:

outlet
{
type cyclic;
}
But I have errors!

Could everybody help me?
Thanks in advance!
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Old   May 6, 2015, 06:21
Default Doubt with transient velocity b.c at inlet.
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Hi guys;

I am relatively new to the forum.
I am trying to inject an air bubble into a fluid of ethanol and see the flow of the air bubble through a rectangular 2D channel as an initial step based on a paper.

I have a rectangular bubble which I would like to relax it from rectangular to (curved at edges due to the influence of surface tension). So, it can take around 0.003s. (Notice time scale is small and I deal with interFoam solver). After, relaxing i inject with a uniform velocity of 0.0167m/s for a brief period of time say 0.01s.

Could you please let me know what sort of a boundary condition is to be used for the inlet and also at the outlet.

Thanks a lot for your patience and help.
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