Hello Eelco,

I followed your thread above but as I am not a C++ programmer I have some problems to understand what you actually did.
I need to set a time dependent BC for heatflux. What I did so far is to create a ramp over time. But if I want the ramp to become a constant value at a certain point in time I don't know how realize it. My idea was to define two expressions, from which one is true for the first part of the calculation, and the other one for the second part, controlling it with an if then else condition like: if time()<=t1 the use expression one, else use expression two.
Is this somehow realizable? If so, how is the syntax?

Thank you in advance
Best, Tony

The problem is that probably the solver doesn't know about source terms for the energy equations so you'll have to do a little bit of C++-programming.
There is an example solver for swak-source-terms in the examples (basically you'll have to add the source-term to the equation and the source term has to be read)
How you specify the zone is up to you: either by an expression or using a cellSet. cellSets can be created with the cellSet-utility. Either use one of the standard cellSet-methods or the one supplied by swak for that. There is a (simple) example for that too

Failing to compile interfoamwithsources
 

Hi Bernhard,

I'm getting error compiling InterFoamWithSources:
Also the nem versions of chtMultiRegionFoam use hrhoThermo.. and the example for groovyBC still uses hPsiThermo, have no sure ideia what you should do....

Using OF-1.7.x... will try latter with OF-1.6-ext ..

Not able to compile swak4foam
 

Hi,

When I try to do wmake in swak4FoamParsers I get following error

SOURCE=FieldValueExpressionParser.yy ; rm -f Make/linux64GccDPOpt/FieldValueExpressionParser.C Make/linux64GccDPOpt/FieldValueExpressionParser.tab.hh; bison -ra -v -d $SOURCE ; mv *.tab.cc Make/linux64GccDPOpt/FieldValueExpressionParser.C ; sed -i.bak "s/position.hh/FieldValueExpressionParser_position.hh/" location.hh ; mv location.hh lnInclude/FieldValueExpressionParser_location.hh ; mv stack.hh lnInclude/FieldValueExpressionParser_stack.hh ; mv position.hh lnInclude/FieldValueExpressionParser_position.hh ; sed -i.bak "s/stack.hh/FieldValueExpressionParser_stack.hh/;s/location.hh/FieldValueExpressionParser_location.hh/" FieldValu[harshad@headhpccluster swak4FoamParsers]$ wmake
SOURCE=FieldValueExpressionParser.yy ; rm -f Make/linux64GccDPOpt/FieldValueExpressionParser.C Make/linux64GccDPOpt/FieldValueExpressionParser.tab.hh; bison -ra -v -d $SOURCE ; mv *.tab.cc Make/linux64GccDPOpt/FieldValueExpressionParser.C ; sed -i.bak "s/position.hh/FieldValueExpressionParser_position.hh/" location.hh ; mv location.hh lnInclude/FieldValueExpressionParser_location.hh ; mv stack.hh lnInclude/FieldValueExpressionParser_stack.hh ; mv position.hh lnInclude/FieldValueExpressionParser_position.hh ; sed -i.bak "s/stack.hh/FieldValueExpressionParser_stack.hh/;s/location.hh/FieldValueExpressionParser_location.hh/" FieldValueExpressionParser.tab.hh ;mv *.hh lnInclude ; touch -r $SOURCE lnInclude/FieldValueExpressionParser*.hh ; g++ -m64 -Dlinux64 -DWM_DP -Wall -Wno-strict-aliasing -Wextra -Wno-unused-parameter -Wold-style-cast -Wnon-virtual-dtor -O3 -DNoRepository -ftemplate-depth-40 -IMake/linux64GccDPOpt -I/home/harshad/OpenFOAM/OpenFOAM-1.6/src/finiteVolume/lnInclude -I/home/harshad/OpenFOAM/OpenFOAM-1.6/src/meshTools/lnInclude -IlnInclude -I. -I/home/harshad/OpenFOAM/OpenFOAM-1.6/src/OpenFOAM/lnInclude -I/home/harshad/OpenFOAM/OpenFOAM-1.6/src/OSspecific/POSIX/lnInclude -fPIC -c Make/linux64GccDPOpt/FieldValueExpressionParser.C -o Make/linux64GccDPOpt/FieldValueExpressionParser.o
FieldValueExpressionParser.yy:40.1-15: invalid directive: `%initial-action'
FieldValueExpressionParser.yy:41.1-44.1: syntax error, unexpected "{...}"
mv: cannot stat `*.tab.cc': No such file or directory
sed: can't read location.hh: No such file or directory
mv: cannot stat `location.hh': No such file or directory
mv: cannot stat `stack.hh': No such file or directory
mv: cannot stat `position.hh': No such file or directory
sed: can't read FieldValueExpressionParser.tab.hh: No such file or directory
mv: cannot stat `*.hh': No such file or directory
g++: Make/linux64GccDPOpt/FieldValueExpressionParser.C: No such file or directory
g++: no input files
make: *** [Make/linux64GccDPOpt/FieldValueExpressionParser.o] Error 1


Can anybody help me?

Sorry. Can't reproduce this with 1.7.x
Try wclean. Have a look whether the regular interFoam compiles for you

Which version of bison do you have (check with "bison -V")?

bison version: 1.875c

Thanks

Thanks for reply
I am using bison 1.875c

Could not 'make' latest version so tried using existing version.

If I googled this correctly this version is from 2003. I don't think that any bison versions with a 1 before the comma knows how to play along with C++. So this version won't work.

Bernhard

Ok
I will try installing latest bison again
Thanks for clarifications

Hy Bernhard,

I've implemented now volume sources for momentum,mass and energy in reactingFoam and now I need to control the sources by an expression, which describes the source behavior over time. But as you can see below, in my source properties I can only specify a constant value instead of an expression.

FoamFile
{
version 2.0;
format ascii;
class dictionary;
location "constant";
object massSourcesProperties;
}
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //

(
source1
{
active true;
timeStart 0.001;
duration 0.05;
selectionMode cellSet;
volumeMode absolute;
fieldData
(
(H2O 1e-1) // kg/s
(CO2 1e-1)
(N2 1e-1)
(O2 1e-1)

);

cellSet heatSource;
}
);

Is this now a case that can be solved with swak4Foam? If so, could you point me to the right example or post where to add the expression and synthax of it. The source zone in the mesh is defined with cellSets.

Thank you in advance
Tony

Yep. In principle it can be done. The only thing is that the solver has to be slightly modified (and of course the case-files). Have a look at the example interFoamWithSources (that comes with the distro) and how it differs from regular interFoam (then modify your solver accordingly). There is also a small example case.

To specify the source just in a cell set foo use this expression "set(foo) ? 1 : 0" instead of 1 use the expression you want to use

Bernhard

Hello Bernhard,

thanx for your quick reply.

One difference is in the createFields.H file:

expressionSource<vector> momentumSource
(
IOdictionary
(
IOobject
(
"momentumSourceDict",
runTime.constant(),
mesh,
IOobject::MUST_READ,
IOobject::NO_WRITE
)
),
mesh
);

In my case I need to add additionally energySources and massSources. EnergySources shouldn't be a problem, as the only changes to make are to set <vector> to <scalar> and to change momentumSource to energySource and so on. But what about massSources. I mean is it possible to control different species over a single massSourceDict? Or do I have to specify for each specie an own dict?

One last question. Is this synthax right in the .C File? I just took the momentumSource synthax from interFoamWithSourcesFoam and adapted it to mass and energy...

if (runTime.write())
{
chemistry.dQ()().write();

volVectorField momSrc=momentumSource();
momSrc.rename("momSrc");
momSrc.write();

volVectorField enegSrc=energySource();
momSrc.rename("enegSrc");
momSrc.write();

volVectorField masSrc=massSource();
momSrc.rename("masSrc");
momSrc.write();
}

Thank you very much,
Tony

oh I'm sorry... like this of course!!!!

if (runTime.write())
{
chemistry.dQ()().write();

volVectorField momSrc=momentumSource();
momSrc.rename("momSrc");
momSrc.write();

volScalarField enegSrc=energySource();
enegSrc.rename("enegSrc");
enegSrc.write();

volScalarField masSrc=massSource();
masSrc.rename("masSrc");
masSrc.write();
}

You're right. That is not as simple as the other sources. But feasible. Basically the way to go would be to create a PtrList of expressionSource<scalar> that is as big as the composition Y. Those sources would have to be initialized in a loop and the appropriate source would have to be used for each species. For getting the specification you either use a separate file for each species (something like 'Y[i].name()+"SourceDict"') or you have one file for all mass sources and get the appropriate dictionary by using 'sourcesDict.subDict(Y[i].name())'. (Both examples are from memory, I'm sure you can work out the details)

BTW: I'm sure you've included the overall mass-source into the continuity equation

That should work. Of course because this happens after the calculation it is possible that the values that are written to disk are slightly different from those used in the equations.

Bernhard

hi,

i am facing the same problem (ld returned 1 exit status). Is it possible that this is somehow related to where the *.o file is written... because i had to manually change the Make/files when compiling swak4Foam. I changed from ../Libraries/... to ../lib/.. and this fixed the "earlier" problem..

neewbie

Hi Bernhard,

I've compiled swak4Foam for both 1.6-ext and 1.7.0. Everything seems okay except for the simpleSwakFunctionObjects library. It is mentioned on the wiki page but does not appear with the other libraries. Looking in the make log file the only reference to simpleFunctionObjects appears in this segment below:

where files timelineFunctionObject.H and patchFunctionObject.H are also missing. Any ides where to get those header files?

Thanks,
Ziad

Yes I have an idea. That information was "hidden in plain sight":
Let me quote from the README-file (sometimes I wonder why I write that stuff):

Right! I had simpleFunctionObjects, just not in $WM_PROJECT_USER_DIR/Libraries

Thanks for the "tip".

Hello Bernhard,

two short questions:

1. what exactly do you mean with your comment:

BTW: I'm sure you've included the overall mass-source into the continuity equation

My Eqns look like this:

UEqn:

fvVectorMatrix UEqn
(
fvm::ddt(rho, U)
+ fvm::div(phi, U)
+ turbulence->divDevRhoReff(U)
==
//rho*g
rho.dimensionedInternalField()*g
+ momentumSource.Su()
);

UEqn.relax();

if (momentumPredictor)
{
solve(UEqn == -fvc::grad(p));
}


...and

YEqn:

for (label i=0; i<Y.size(); i++)
{
if (Y[i].name() != inertSpecie)
{
volScalarField& Yi = Y[i];

solve
(
fvm::ddt(rho, Yi)
+ mvConvection->fvmDiv(phi, Yi)
- fvm::laplacian(turbulence->muEff(), Yi)
==
//kappa*chemistry.RR(i),
kappa*chemistry.RR(i)().dimensionedInternalField()
+ massSource.Su(i),
mesh.solver("Yi")
);

Yi.max(0.0);
Yt += Yi;

Is there something wrong regarding the specie fractions or what else do you mean?

2. Do you know where to get the properties set for CO in the same "form" like other species used for reactingFoam? OpenFOAM support doesn't help unfortunately...

Many thanx in advance,
Tony