[ziemowitzima]

Dear OFoamers,

I am working on some problem with time dependent domain. Namely one of the borders of the domain is changing with time.
I was able to make my mesh time dependent and it works fine, but I encountered some other difficulty which I cant understand/solve.

Namely, after mesh is changed, solution behaves wrong. Some energy is added to the system. It happens only during first change of the domain. Consecutive changes do not show this strange behavior any more (solution behaves as it should)

You ca see it on the animation here:
http://youtu.be/wIexKK2vQ-8

from time 0 - 0.5 everything is ok
for t =0.5 there is change of the domain geometry
from time 0.5 - 1 we can see this "strange" behaviour, some extra energy is added and blue patch is moving (in fact it should not)
at time t = 1 there is change of the geometry again, but now (and later as well) everything seems to be ok (no extra/phantom energy is added).

Summing up, there is some problem after first change of the mesh.

Equation I am solving is just:

fvScalarMatrix omEqn
        (
        dimDt*fvm::ddt(om)
        + dimG*fvm::div(phi, om)    
      - fvm::laplacian(dimensionedScalar("1",dimensionSet(0, 2, 0, 0, 0),1), om)      
        );        
        omEqn.solve();

but the same happens as well for

fvScalarMatrix omEqn
        (
        dimDt*fvm::ddt(om)
      - fvm::laplacian(dimensionedScalar("1",dimensionSet(0, 2, 0, 0, 0),1), om)      
        );        
        omEqn.solve();

Do you have any idea why it is like that ?
Thanks
ZMM