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achuneka August 5, 2008 23:42

My case is Flow through a Vent
My case is Flow through a Venturi and I am using lesCavitatingFoam. BC - Velocity inlet and uniform pressure outlet.

I would like to run the case for a higher value of outlet pressure to get initial set of field values.

I then want to reduce the outflow pressure and continue running it further. I am running the job in parallel.

The problem is the modification of boundary conditions in the time files formed.

Please let me know

mattijs August 6, 2008 04:40

- Stop the simulation and edit
- Stop the simulation and edit the last time dump (in all the processor directories). Set startTime to latestTime and restart

- Or use one of timeVaryingUniformFixedValue or timeVaryingMappedFixedValue to automatically vary a fixedValue b.c. (search this forum - see simpleFoam/pitzDailyExptInlet tutorial)

achuneka August 6, 2008 09:20

Thanks Mattijs. The problem
Thanks Mattijs.

The problem in doing that is this.

The BC for pressure in a "non-decomposed" file looks like this.

type fixedValue;
value uniform 2e5;

When I decompose the file into n number of processors, on each processor the file looks like

type fixedValue;
value nonuniform 0();

Followed by a list of faces which actually have the same value 2e5.

Same thing applies in the boundary section of dumped time files.

So now if I have to modify these files, I have to
change each of them. Is there any other way to do that ?

olesen August 6, 2008 09:36

Did you try with 'reconstructP
Did you try with 'reconstructPar', edit the boundary files, 'decomposePar -fields' and then restart?

Or else, if you use the time-varying boundary condition like Mattijs mentioned, you can do a restart without needing to edit the field values themselves. The new value will get taken from the file.

achuneka August 6, 2008 11:21

Thanks Mark... reconstructPar
Thanks Mark... reconstructPar works ..

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