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Handling boundary condition in Fluent

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Old   August 29, 2005, 22:22
Default Handling boundary condition in Fluent
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sak
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Hi Fluent users, i have a question, like in the geometry the periodicity between the boundaries is a mixed type of translation and rotation.

the boundaries are periodic but in fluent while dealing with boundary conditions, i cant select the boundary as both translation and rotation.

any idea as how to handle the conditions if the periodicity is both translation and rotation.

thanks in advance
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Old   March 24, 2013, 07:22
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Alexey Zakharov
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Quote:
Originally Posted by sak
;123800
Hi Fluent users, i have a question, like in the geometry the periodicity between the boundaries is a mixed type of translation and rotation.

the boundaries are periodic but in fluent while dealing with boundary conditions, i cant select the boundary as both translation and rotation.

any idea as how to handle the conditions if the periodicity is both translation and rotation.

thanks in advance
Hi Sak!

I am intresting this problem too) My mesh in this image
SWIRL_STABE.jpg
Do anyone have ideas how create both translation and rotation periodic in fluent?

Thanks
Alex.
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File Type: jpg SWIRL_STABE.jpg (26.5 KB, 14 views)
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Old   March 25, 2013, 04:33
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Paritosh Vasava
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I think you could write a UDF about mesh motion that has both rotation and translation. This along with options about 'mesh motion' in 'Cell Zone Condition' should resolve your problem.
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Old   March 25, 2013, 06:27
Default Total pressure at the outlet is more than inlet
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deepthi
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hi
I am doing 3d modelling of a can combustor using k-e model.If I give mass flow inlet and pressure outlet or pressure inlet and pressure outlet I am getting total pressure at the outlet is more than total pressure at inlet.But there should be a pressure drop in reality in a combustor.Can u help?
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Old   March 25, 2013, 09:01
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Thiagu
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Pls check the location / methods (massflow weighted\area weighted average).
# what is inlet mach number (assuming subsonic)
# what are teh values of To,Ptot inlet To,Ptot outlet values
# what is the Ps in and out
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Old   March 25, 2013, 11:35
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deepthi
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Its subsonic and pin=200000 and pout=212000 and the case is running well and giving results but in reality there should be pressure loss and here pressure is increasing..lets consider cold flow T=300k.In both cold flow and hot flow total pressure is increasing..
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Old   March 25, 2013, 16:21
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Alexey Zakharov
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Hi Vasava!
Thanks for you reply!

But I am some questions about this problem
Is it better to use: mesh motion or frame motion in my case?
And how I am can set velocity (translation and rotation) mooved mesh or referense frame? Constants?
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