Mesh replacement in sub-domains while cfx simulation is in progress
 

Hi,
I am conducting an unsteady simulation of a turbine which includes stationary domain-1, Rotating domain, and stationary domain-2. The rotating domain is connected through transient rotor-stator interface at both sides, i.e., upstream and downstream.

Now i am using mesh deformation in stationary domain-1. After certain time steps (for example 100), i want to replace the mesh with new mesh and so on..

I only want to replace mesh in the stationary domain. I do not want to replace the mesh of the other two domains and do not want to initialize these two domains with previous time step as it produces very big jump in all the parameters after interpolation.

I cannot use automatic re-meshing in cfx since i have created hexahedral mesh with ICEM CFD blocks. No tetra, no prism.

I know the deformed mesh position after 100 time steps in stationary domain-1 so the my new mesh will start from that point and go ahead for next 100 time steps likewise...

Multi-configuration will not work since it requires new mesh in all domains. Does anybody know how to replace mesh in sub-domain only?

I will be very much thankful for your suggestions/ideas.

I cannot see how you can do this without interpolation and that will result in a jump in parameters. The jump should be small - or at least it should settle back down to the expected values quickly.

Thank you for your reply. I am needed to change mesh in stationary domain-1 only. Parameters jump related to this domain is acceptable. But i wanted to avoid jump in other domains mainly runner. Because, after 100 time step, the runner position is different. If i replace mesh in entire turbine there will be parameters jump everywhere. Is there any idea how to change mesh in one domain only while simulation is in progress?

Are you trying to replace the mesh, or modifying the coordinates of the existing mesh ?

If you are trying to replace the mesh, i.e. possibly new topology (mesh count and connectivity), you must shutdown, recreate the definition file and restart.

If you are trying to modify the coordinates of the existing mesh, and maintain the same topology (mesh count and connectivity), you can UserFortran. The details for the mapping a user supplied coordinates to the existing mesh are explained in the documentation. There used to be a tutorial illustrating its use, but not sure if it still exists.

Hope the above helps,

Thank you for Reply. I want to replace the mesh. After 100 time step, mesh quality is too low. So i would like to replace with new mesh of that domain only, without changing mesh in other domains which are connected through GGI interface.