Problem between rhoLTSPimpleFoam and mesh.update();
I've modified the rhoPimpleFoam solver (OF2.2) to add a mesh morphing. It is a very small node displacement (1/10 of the first cell height) so I didn't setup the absolute phi.
With the rhoPimpleFoam solver, everything goes well. However, if I apply the same modification to the rhoLTSPimpleFoam, it doesn't work anymore. I get an error about dimensions which seems to come from a rho factor (kg.m-3 missing).
I've found that if I remove "mesh.update();" from my solver, it works perfectly. Then, I found that the error comes from the "pEqn.H" and more precisely from the phid calculation.
Has anyone an idea of the origin of the problem ? It seems to come from the localEuler scheme but I can't identify the source.
If I set the ddt scheme to Euler, my simulation runs smoothly. However, with a localEuler, the simulation crash during the first iteration.
Origine of the Error
Finally I can answer my question.
The problem comes from the fact that mesh.update() turns mesh.moving() to be true (no surprise here). The problem is located in the "localEulerDdtScheme.C" in src/finiteVolume/finiteVolume/ddtSchemes/kicakEulerDdtScheme.
The scheme ddtPhiCorr() is simply not implemented for a compressible solver having the mesh moving. There is a "if (mesh().moving())" leading to a single scheme which is only suitable for incompressible solver. However, if mesh().moving()=false, the scheme has 3 choices depending of the dimension of phi and U.
To solve my problem I've simply decided to ignore the mesh motion ! indeed, my displacement is of about 1e-7 meter per time step (which are 1e-3 second) where my first cell height is about 1e-4.
To do so, only add: "mesh.moving(false);" after your "mesh.update();".
With this code, the following solver think that the mesh is steady and so it doesn't compensate the motion of the boundary/mesh (which is wrong but acceptable for very small displacement).
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