[alisina-s]

Hi everybody
In my implementation I need to multiply a tensor with div operator.
Does anyone know that It is possible in openfoam to crate a tensor with 12 elements?
my tensors need to have 12 components but I get the error regarding that I can not go further 9 elements.
I did like this in my createfield
volTensorField j2
(
IOobject
(
"j2",
runTime.timeName(),
mesh,
IOobject::NO_READ,
IOobject::NO_WRITE
),
mesh,
dimensionedTensor( "j2Tensor", dimless, tensor(0,0,0,0,0,0,-1,0,0,1,0,0) )
);

and then
j2 & fvc::div(phi,u2)
-------------------------------------------
generally I want to know even is it possible to have tensors with more than 9 components???
thanks a lot in advance

[mprinkey]

"Tensors" in OpenFOAM are only rank-2. That is nine elements in 3D. I don't know what rank/symmetries gives you a tensor with 12 components, but OpenFOAM doesn't support it by default.

http://www.foamcfd.org/Nabla/guides/...sGuidese4.html

If you need to multiply a 4x3 matrix by a div operator, you can split the div operator apart to get the x,y,z components and multiply everything out by hand.

[alisina-s]

Thanks Micheal for your answer,
can you also mention how can I split the div component?
Regards,
ALI

[mprinkey]

Originally Posted by alisina-s

Thanks Micheal for your answer,
can you also mention how can I split the div component?
Regards,
ALI

It is on the same page I quoted above. x(), y() and z() are the access functions for a vector. If T is a rank 2 tensor, fvc::div(T) is a vector. fvc::div(T).x() is the x-comp, etc.

This presentation gives you all of the details that you need:

http://www.tfd.chalmers.se/~hani/kur...rogramming.pdf