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Variable inlet size with only one mesh

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Old   March 24, 2010, 08:38
Default Variable inlet size with only one mesh
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My case consists on a box 10x10x10 with 4 outlets (one each side at the botton) and on inlet in the center of the box top.
The problem is that i have serveral sizes of inlet to test (0.16m²,0.25m²...2m²).
I did one mesh with several blocks and all the outlets, but the inlet is not specified. Can i use this mesh with the bigger inlet surface and do all simulations just changing the inlet variable/function at the top?
It will be like a 2m² inlet, but in one simulation just 0.16m² will have an airflow and so on.
Is it possible?

Thanks
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Old   March 24, 2010, 15:27
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Quote:
Originally Posted by lindner View Post
I did one mesh with several blocks and all the outlets, but the inlet is not specified.
How can you create an inlet without specifing it?
Is it an inlet or not?
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Old   March 24, 2010, 19:09
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I created an inlet with 1m², i did the simulation and its everything working.
Now i want to change the inlet to 0.75m² and later 0.5m², 0.2m² and 0.16m².
Is there a way to do this without changing the mesh? like a function that specifies 0.5m² with a velocity and the rest of the inlet with 0 velocity.

thanks
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Old   March 25, 2010, 04:37
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Quote:
Originally Posted by lindner View Post
I created an inlet with 1m², i did the simulation and its everything working.
Now i want to change the inlet to 0.75m² and later 0.5m², 0.2m² and 0.16m².
Is there a way to do this without changing the mesh? like a function that specifies 0.5m² with a velocity and the rest of the inlet with 0 velocity.

thanks
If you know an explicit function which describes what you want you can use the tool groovyBC tool. It can manage functional boundary conditions.

Otherwise you will have to change the mesh. There is even a way of making a parametric mesh with the m4 preprocessor. The input to the m4 could be your inlet size.
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Old   March 25, 2010, 10:15
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Originally Posted by sega View Post
If you know an explicit function which describes what you want you can use the tool groovyBC tool. It can manage functional boundary conditions.

Otherwise you will have to change the mesh. There is even a way of making a parametric mesh with the m4 preprocessor. The input to the m4 could be your inlet size.
That's exactly what I was looking for! Now i will study both methods and see witch one is easier to implement on my simulation.
Thank you very much Sebastian!
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