[SprayStef]

Hi,

I'm a total newbie to OpenFOAM and need some help...

This should be easy but I can't seem to find the answer anywhere...

I'm modifying SprayFOAM in various ways. For now I've started by adding a new member function to reactingCloudI.H and I'm going to implement a new evaporation model. --> All changes in lagrangian/intermediate...
After making my changes I successfully compiled my library --> libmylagrangianIntermediate.so , which is now be stored in $(FOAM_USER_LIBBIN).

I included the library with:
-I$(FOAM_USER_LIBBIN)/libmylagrangianIntermediate

When I compile mySprayFoam (that's my modified solver), it doesn't see the library because it gives an error that the member function (the one, I defined in my library) does not exist.

Can anybody help?

Thanks so much,
Stef

[floquation]

Hi,


I'm reasonably new (8 weeks) to OpenFOAM (and C/C++ for that matter) as well, but I figured your question would be a nice exercise to understanding libraries in C.


In the past 2.5 hours I came to the following conclusions:

1. When you're trying to compile code 'myExe' which uses library 'myLib', the compiler for myExe will need to have access to the header file originally used to generate myLib. This is done using the -I compiler flag, linking to the directory in which the included .H file is contained, e.g.: foo.H.
   • If this is not done, you get the following error:

     • myExe.c:2:17: fatal error: foo.h: No such file or directory
        #include "foo.h"

   • It needs this, since myLib contains solely machine code, which myExe can execute. However, at this point (compile-time) you still have a .C code which cannot read the machine code. --> You need a header file containing the declarations for methods/function of myLib which myExe wants to use.
     • Anyone knows why it cannot just read the machine code? After all, it does so in the next step as well:
2. Additionally, you need to specify the library using the -lLibName compiler flag (and possibly -LlibDir), from which your myExe-compiler can see that the declared methods are indeed implemented -> ?it reads machine code now?
   • If this is not done, you get one of the following errors (where "foo" is the name of the function to be called).
     • You did not include the library (-lLibName)
       

       /tmp/ccUxHJpQ.o: In function `main':
       myExe.c:(.text+0xf): undefined reference to `foo'
       collect2: error: ld returned 1 exit status

     • You forgot -LlibDir->
       

       /usr/bin/ld: cannot find -lfoo
       collect2: error: ld returned 1 exit status

3. Then, at run-time, your executed myExe will need to relocate the library (shared object files are dynamically linked). It does so by reading your $LD_LIBRARY_PATH environment variable. The path containing your library (probably $FOAM_USER_LIBBIN) should be included in that environment variable.
   • If this is not done, you get the following error:

     • ./myExe: error while loading shared libraries: libfoo.so: cannot open shared object file: No such file or directory

So, for your specific question, you will need the following statements in Make/options:

-L$(FOAM_USER_LIBBIN)
-lmylagrangianIntermediate
-I$YOUR_HEADER_DIR

For my test code, this would look like:

Make/files
myExe.c

EXE = testWMake                             

Make/options
EXE_INC = \
    -I../fooLib

EXE_LIBS = \
    -L$(FOAM_USER_LIBBIN) \
    -lfoo

(That creates an executable. If you want to create a library, use "LIB" and "LIB_LIBS" instead.)


Good refs:
http://www.openfoam.org/docs/user/co...plications.php
http://www.cprogramming.com/tutorial...linux-gcc.html


~ Kevin

[SprayStef]

Hey Kevin,

thanks so much!!!
That help me with my problem AND helped me understand libraries in C++ a little better.

Stef

[SprayStef]

Hi again,

now I've sucessfully added some functions to the ReactingCloud Template in my library, but a new issue arouse...

I added a new Evaporation Model / PhaseChangeModel.

added the following lines to intermediate/parcels/include/makeReactingParcelPhaseChangeModels.H:

#include "MyEvaporation.H"

and

makePhaseChangeModelType(MyEvaporation, CloudType);

When I run my case with the myEvaporation option I get the following error message:


--> FOAM FATAL ERROR:
Unknown phase change model type myEvaporation

Valid phase change model types are:

3
(
liquidEvaporation
liquidEvaporationBoil
none
)


From function PhaseChangeModel<CloudType>::New(const dictionary&, CloudType&)
in file /home/astefani/OpenFOAM/astefani-2.1.1/run/../lib_myLagrangian/intermediate/lnInclude/PhaseChangeModelNew.C at line 54.


Why is my PhaseChangeModel not in the list yet?
Any ideas on what I could have done wrong or forgotten?


Thanks,
Stef

[floquation]

Is this line in your "myEvaporation.H" file?

public:

    //- Runtime type information
    TypeName("myEvaporation");

Alternatively... Did you recompile the C-file which calls intermediate/parcels/include/makeReactingParcelPhaseChangeModels.H?
I.e. lagrangian/intermediate/parcels/derived/basicReactingParcel/makeBasicReactingParcelSubmodels.C (and similar for the other possible cloudTypes).

[ms6918]

Hello,
I am trying to add some of the Openfoam libraries(like lagrangian etc.) in flameletFoam. My openfoam and flameletfoam are compiled seperately. My solver did compile but when i ran solver it gave error stating Duplicate entries.

I am starting to wonder that i may have not compiled the libraries correctly. I started by copying my openfoam libraries in flameletfoam and compiling them in flameletfoam. Then in my solver in flameletfoam, i called some of the libraries from flameletfoam and some(like meshTools, sampling etc.) from Openfoam.

Is this the correct approach?

Kindly consider my request. It would be a great help.

Sincelery,
beginner