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James Date May 23, 2005 15:57

The ever growing .def file!
Has anyone noticed that if you successfully re-start a simulation using the interpolate function, the .def just keeps growing! Surely, it makes sense to only store the last values interpolated onto the mesh and not every interpolated set!. Does anyone know how to stop this happening, as it seems a terrible waste of space when it comes to archiving the .def files after finishing one's analysis work?


Rui May 23, 2005 20:33

Re: The ever growing .def file!

I've also noticed that if you have a .def file (simulation.def) and create a .ccl file from it (sim.ccl), everytime you do the command: cfx5cmds -def simulation.def -text sim.ccl -write , the size of simulation.def increases by the same amount.

So it seems that everytime a .def file is re-written by this way, even if it exactly the same, its size increases.

However, when you open simulation.def in CFX-Pre and re-write with same name, its size doesn't increase, actually it goes back to the original size.



Juan Carlos May 23, 2005 22:30

Re: The ever growing .def file!

After a .def file is written by CFX-Pre, any modification to the commands file (.ccl file) is recorded into the file.

The CFX internal file manager does not delete the old .ccl data, but appends to it for multiple reasons. For a .res (results file) the .ccl cannot be altered and it is stored in such a way that no user can modify it. Any additional modification is stored separately within the file for future restarts, but the .ccl that matches the stored solution remains intact such CFX-Post works with a consistent set of solution field and physics.

The amount a .def file grows due to changes to the .ccl file is negligible compared to its size.

I am not sure about the increase in size due to interpolation, but I understand that interpolating from a .res to a new .def makes the new .def file a "pseudo-.res" file. Interpolation from .res to .def file is usually due to either mesh differences, or topological changes. Why do you want to interpolate a .res file to the same .def file multiple times?

I would contact CFX support, and describe the behavior you have observed.

Good luck, Juan Carlos

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