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Problem with using MRF Model for verical axis wind turbine Model

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Old   March 15, 2016, 02:01
Default Problem with using MRF Model for verical axis wind turbine Model
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hello everyone here,
i m doing VAWT simulation for Torque Value by creating interface between rotating and stationary domain in Fluent.

After creating interface it also creates additional wall-Fluid-wind & wall-Fluid-MRF.

When say check case it shows comment-"Review wall motion. Stationary wall motion relative to adjacent cell zone detected."

BCS Used:

Fluid MRF: Rotating Domain
Relative to cell zone-Absolute-Angular Velocity 10 rad/s(95 rpm)
wall blade-Stationary Wall

Fluid Wind-Stationary Domain
Inlet-5 m/s,
Outlet- 0 Pa

I am confusing about how to overcome this problem.
help me plse.
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Old   March 15, 2016, 03:59
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Hello Raj,

Do you have any walls that are located inside the rotational part of the domain that are set to be a moving wall, but with a velocity of 0 (with respect to the domain it is in)?
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Old   March 15, 2016, 05:49
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Quote:
Originally Posted by CeesH View Post
Hello Raj,

Do you have any walls that are located inside the rotational part of the domain that are set to be a moving wall, but with a velocity of 0 (with respect to the domain it is in)?
Hello sir,
As i said it creates two extra wall on both the side after creating interface.
I. interface-interior-1-1
II. interface-side1-wall-int_1 (Fluid MRF side)
III. interface-side2-wall-int2 (Fluid Wind Side)

I tried also selecting that wall with rotating wall with zero velocity(Relative to cell zone) but it shows same message after clicking Check Case.
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Old   March 15, 2016, 05:57
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can you show a picture of these walls? i am not quite sure what you mean
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Old   March 15, 2016, 06:32
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Quote:
Originally Posted by CeesH View Post
can you show a picture of these walls? i am not quite sure what you mean
plse find attached pictures
Attached Images
File Type: jpg interface.jpg (106.8 KB, 52 views)
File Type: jpg BCS.jpg (96.1 KB, 42 views)
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Old   March 15, 2016, 06:43
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And I guess these walls are not supposed to be there, right? (do you see them when you display your wall meshes?)

Did you create your interface as a coupled wall or something like that?
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Old   March 15, 2016, 06:53
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Quote:
Originally Posted by CeesH View Post
And I guess these walls are not supposed to be there, right? (do you see them when you display your wall meshes?)

Did you create your interface as a coupled wall or something like that?
after selecting coupled wall again it creates some additional walls...plse find attached pictures for reference.

really sorry for my bad english.
Attached Images
File Type: png Coupled Wall.png (28.8 KB, 27 views)
File Type: jpg Coupled wall2.jpg (125.3 KB, 41 views)
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Old   March 15, 2016, 06:58
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Quote:
Originally Posted by CeesH View Post
And I guess these walls are not supposed to be there, right? (do you see them when you display your wall meshes?)

Did you create your interface as a coupled wall or something like that?
u r right sir...these wall should not be there...also no interior option is available in boundary condition for the same.
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Old   March 15, 2016, 07:00
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They may occur if you set the interface as coupled walls, did you do so? If so, remove the interface and re-create it, setting no coupled wall or so.
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Old   March 15, 2016, 07:06
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Quote:
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They may occur if you set the interface as coupled walls, did you do so? If so, remove the interface and re-create it, setting no coupled wall or so.
I did the same.
also it shows note in console window after creating interface

"Note: Slitting sliding interface zone 43 into a coupled wall.

creating interface-wall1-1-1-shadow
Info: Interface zones overlap for mesh interface interface.
This could adversely affect your solution."
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Old   March 15, 2016, 07:15
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Quote:
Originally Posted by CeesH View Post
They may occur if you set the interface as coupled walls, did you do so? If so, remove the interface and re-create it, setting no coupled wall or so.
i dont no more about coupled wall in interface window...but i think we use coupled wall when there is transfer of energy from one fluid to other(Non Mixing of Fluid).
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Old   March 15, 2016, 07:25
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yes, but I guess you want fluid flow to pass through the interface, so you don't want a coupled wall. Are both sides of the interface well connected? Or is there a gap between them? How did you separate the rotating and stationary zone in your geometry design?
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Old   March 15, 2016, 07:33
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Quote:
Originally Posted by CeesH View Post
yes, but I guess you want fluid flow to pass through the interface, so you don't want a coupled wall. Are both sides of the interface well connected? Or is there a gap between them? How did you separate the rotating and stationary zone in your geometry design?
actually mesh pattern on both side interface wall is different.Should be there mesh connectivity between the two sides of interface.
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Old   March 15, 2016, 07:37
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As far as I know that is not necesarry, I've done some runs with non-matching interfaces and that worked fine. But they do have to be connected; there may not be a gap between the sides.
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Old   March 15, 2016, 21:41
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is there any minimum criteria for mesh element matching on two interface wall
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Old   March 16, 2016, 04:28
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Not that I know of.
Can you perhaps send me your .msh file? I can take a look at it. (if you send it via mail, please do zip it, otherwise outlook won't open it).
I'll send you my details
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