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Old   October 9, 2013, 11:49
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izna O'connor
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Hi..
I am simulating flow around some shapes, in 2D.
I used simpleFoam and PCG solver with K-epsilon . My aim is to put my 3 boundaries as Outflow.. and my 1 bounday as inlet..

Hence i use the Zero gradient bC.. But alas i obtain the following results..

Can anyone please advice me on which BC to use and how please..

Last edited by izna; October 10, 2013 at 03:59.
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Old   October 14, 2013, 08:18
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Artem Shaklein
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Hello, izna O'connor.
Is your flow supersonic? If not, you should specify pressure or velocity at outlet (i.e. not zeroGrad for all variables).
Are you sure that substance strictly flows out through this 3 boundaries (by physics, not by mathematics)? If so, you can cast restriction by using following BC "type inletOutlet; inletValue uniform (0 0 0); value uniform (0 0 0);".
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Old   October 14, 2013, 08:30
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izna O'connor
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hello ARtem..

can you please check those posts? boundary condition porblem..

I cannt run it with simpleFooam and its not supersonic..
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Old   November 2, 2013, 07:00
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Yao Lu
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Quote:
Originally Posted by izna View Post
Hi..
I am simulating flow around some shapes, in 2D.
I used simpleFoam and PCG solver with K-epsilon . My aim is to put my 3 boundaries as Outflow.. and my 1 bounday as inlet..

Hence i use the Zero gradient bC.. But alas i obtain the following results..

Can anyone please advice me on which BC to use and how please..
Hi, izna!

Have you found out the way to simulate outflow BC with openfoam?

I'm solving a flow around cylinder case with interFoam. I have tried freestream and freestreamPressure BC in U and p files. However, the drag coefficient doesn't match the values announced in papers.
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