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Old   April 20, 2012, 08:14
Default Symmetry Boundary Condition
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Dear all,

I'm sorry I didn't find an explanation to my question in the ANSYS Help, so I have to ask here:

When I'm using a symmetry boundary condition in my simulation, which divides my geometry in two equal parts, will I have to impose half of the mass flow or anyway the full mass flow as my boundary condition?

Thank you in advance for your reply.

Best regards,
Stefan
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Old   April 20, 2012, 09:52
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Old   April 20, 2012, 10:13
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Yes, Far is right.

The mass flow must be proportional to the partion, meaning that if you divide the domain in two parts, the mass flow must be 1/2 of what it would be on the whole domain. If you divide it in 6 parts, it should be 1/6 of the total mass flow, etc...
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Old   April 23, 2012, 02:18
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http://en.wikipedia.org/wiki/Intensi...ive_properties
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Old   May 1, 2012, 02:17
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Thank you for your help!
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Old   August 30, 2012, 09:06
Default boundary condition (symmetry vs periodic doubt)
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Dear friends,
i am doing 3D wing analysis, i have doubt on boundary conditions in fluent ie both symmetry and periodic, anybody have the answer please let me know briefly,for what kind of purpose to use symmetry & periodic boundary conditions, please tell any example with problem.
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Old   August 31, 2012, 04:25
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Hi
Quote:
Originally Posted by hhh View Post
Dear friends,
...for what kind of purpose to use symmetry & periodic boundary conditions, please tell any example with problem.
if u have e.g. a large cooler with periodic elements or pipes where u don't want to simulate large inflow regions to have the desired velocity profiles, u can simulate relative small meshes and that reduces the amount of time to process -> especially useful if u want to simulate lots of parameter variations(e.g. in a DoE project)

if your 3D-wing isn't symetric at all, then ...
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Old   August 31, 2012, 06:56
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Mathematically a symmetry boundary is zero normal velocity and zero normal gradient on all other terms, and periodic boundaries have all values equal on the equivalent locations on both boundaries.
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