[mattijs]

programmers guide : Sf is face area vectors (Table 2.1), & is inner product (Table 1.2)

[sleepdeprivation]

See http://www.tfd.chalmers.se/~hani/kur...7/rhiechow.pdf

U = rUA*UEqn.H(); isn't U, its half the update to U. U is used as a storage location
U-=rUA*fvc::grad(p); completes the update to U
so in total U = rUA*UEqn.H() - rUA*fvc::grad(p); but you have to find pressure first

[jorkolino]

Originally Posted by alberto

You're right. Just shorter:

volScalarField myVectorField("myVectorField", myVector & mesh.C());

Regards,
Alberto

What shall I put instead of myVector? The program complains that transportProperties is not defined in this scope, so I need to set myVector here, directly.

regards

[arashfluid]

Hi,
I have added a source term to the momentum equation in foam-extend-3.1 FSI solver and encountered the following error:


/home/arash/foam/arash-3.1/lib/linux64GccDPOpt/libfluidStructureInteraction.so: undefined reference to `Foam::flowModels::icoFlow::Fy() const'
/home/arash/foam/arash-3.1/lib/linux64GccDPOpt/libfluidStructureInteraction.so: undefined reference to `Foam::flowModels::icoFlow::E() const'
/home/arash/foam/arash-3.1/lib/linux64GccDPOpt/libfluidStructureInteraction.so: undefined reference to `Foam::flowModels::icoFlow::F() const'
/home/arash/foam/arash-3.1/lib/linux64GccDPOpt/libfluidStructureInteraction.so: undefined reference to `Foam::flowModels::icoFlow::xx() const'
/home/arash/foam/arash-3.1/lib/linux64GccDPOpt/libfluidStructureInteraction.so: undefined reference to `Foam::flowModels::icoFlow::yy() const'
/home/arash/foam/arash-3.1/lib/linux64GccDPOpt/libfluidStructureInteraction.so: undefined reference to `Foam::flowModels::icoFlow::Ey() const'
/home/arash/foam/arash-3.1/lib/linux64GccDPOpt/libfluidStructureInteraction.so: undefined reference to `Foam::flowModels::icoFlow::Fx() const'
/home/arash/foam/arash-3.1/lib/linux64GccDPOpt/libfluidStructureInteraction.so: undefined reference to `Foam::flowModels::icoFlow::centers() const'
/home/arash/foam/arash-3.1/lib/linux64GccDPOpt/libfluidStructureInteraction.so: undefined reference to `Foam::flowModels::icoFlow::sw() const'
/home/arash/foam/arash-3.1/lib/linux64GccDPOpt/libfluidStructureInteraction.so: undefined reference to `Foam::flowModels::icoFlow::Ex() const'
collect2: ld returned 1 exit status
make: *** [/home/arash/foam/arash-3.1/applications/bin/linux64GccDPOpt/fsiFoam] Error 1


what's problem?

[cikas]

Hello every one

I am trying to simulate a permeable wall with add source term in mass equation. I separated the cells near the wall and add source term as UDF. But the results shows that it does not work because the difference between inlet and outlet mass flow rate is not equal to integral of source term for all separated cells.Please help me.

Cikas

[yfjok22]

Dear Elnaz,

I'm working on similar problem
Would you give some details, so that maybe I could help you

[openfoam_aero]

Hi Sambatra.
I know this is an old post but I’m replying to it for the benefit of others.
UEqn.A() (access function?)
So basically this is the function that belongs to the UEqn object. The UEqn object has the matrix of coefficients once the equation that is held by it is discretised. Now this matrix can be split into a diagonal matrix (containing only diagonal entries) A. The reason this is done is because it is easy to calculate the inverse of a diagonal matrix. Assume the discretised form to be MU = -grad(p). Split MU = AU - H where U is the vector of velocities, A is the diagonal matrix and H is the matrix of what remains. Substituting, you get AU = H - grad(p). Now A^-1AU = A^-1H - A^-1grad(p) = H/A - grad(p)/A. Therefore
U = H/A - grad(p)/A. This equation is written in OpenFOAM as UEqn.H()/UEqn.A() - FVC::grad(p)/UEqn.A(). Coming to your next question
fvc::interpolate(U) & mesh.Sf() - this is to calculate the flux at the cell face. You know that in OpenFOAM, values are stored in the cell centres. They have to be interpolated onto the cell faces if the fluxes have to be calculated. That expression literally translates to U.nDS where U is the interpolated velocity, mesh.Sf() is the area vector at a given cell face.