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RX November 24, 2006 12:01

change cell types
Hi! Can I change cell types when I am running the job?

If I can, how to do that?

Any suggestion will be highly appreciated!

notdiscl November 24, 2006 18:02

Re: change cell types

RX November 24, 2006 18:51

Re: change cell types
I wanna simulate a kind of open chanel flow with the valve, actually just a board which seperate the water part and air one. At first I wanna use moving mesh, but failed as mentioned in yesterday's message. So I wanna change the cell type during running time. Then I can simulate the movement of the board. You told me it is impossible.

So do you have any ideal about that?

Anton Lyaskin November 27, 2006 09:14

Re: change cell types
What about cell activation/deactivation?

RX November 28, 2006 07:02

Re: change cell types
Thank you! I will try it!

RX November 28, 2006 12:07

Re: change cell types
It does not work. I cannot deactivate a cell connected with others. That is what star-cd told me.

Anyone can give me some help?

Thanks in advance.

Anton Lyaskin November 29, 2006 02:02

Re: change cell types
Can you describe your geometry in more details? Or give a picture?

RX November 30, 2006 07:21

Re: change cell types
my geometry is shown as follow. __________________________________________________ * * * * * * * * * *--------------* * * --- * *--->tank * - *--->gate * * * * * * * * * * __________________________________________________

In the middle of the tank, there is a gate, which seperates the whole simulation domain into two parts. The left part is filed with water. The right part is empty. Then the gate moves upwards with a velocity of 1.5m/s. So I wanna simulate the process. Wish you can help me.

Many Thanks!

Anton Lyaskin November 30, 2006 07:33

Re: change cell types
Ok, now I've got it. The only thing I can think of now is moving mesh with ASI, with unmatched parts of "Attach" regions setting to Wall, but I (or you ;) have to check, if it will work or not.

The idea is you have a block of compressed mesh below the gate, which expands as the gate moves upward. This block is coupled to mesh in left and right parts via ASI. In the beginning it has small but finit thickness (because you can't activate/deactivate cells!), but I think it's ok. The density of mesh for left and right part should be chosen in such a way, that this block expands one cell at a time step (I meen cell in left/right part), otherwise you'll have partial boundaries at ASI.

RX November 30, 2006 08:21

Re: change cell types
Many Thanks!

Yes, I will try it!

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