[ziemowitzima]

Dear Foamers,

I am trying to solve following problem:
Fun = Fun (x,y)
Fun_xxxx = f(x,y),
where ()_xxxx, denotes 4th order derivative in respect to x.
To do this I changed the original problem to, set of two two-order equations:

H_xx = f(x,y)
Fun_xx = H.

To solve it in OpenFoam I am usning fvm::laplacian(1D,fun) operator with 1D being a tensor, definite as follows:
1D = (1 0 0;
0 0 0;
0 0 0),
what force laplacian operator to act only in x-direction.
In OF it looks like:

solve
(
fvm::laplacian(1D, H) - f
);
solve
(
fvm::laplacian(1D, Fun) - H
);

But unfortunately it gives wrong results ...
Does anyone of you know what is here wrong ?

thanks a lot
ZM