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Skin Friction co-efficient (Cf)

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Old   May 22, 2013, 02:24
Default Skin Friction co-efficient (Cf)
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Nil
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Hello all,

I need to insert the value of skin friction co-efficient (Cf) into my design [left ventricle of the heart], but I don't know how to input it in ANSYS CFX 14.0. I need to know how to insert the value of Cf in the wall with NO SLIP boundary condition. Any help would be highly appreciated.

Thanks!
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Old   May 22, 2013, 05:54
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This will work back to a wall shear stress. So use the wall shear stress boundary and write a CEL expression from your Cf.
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Old   May 22, 2013, 05:58
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Thanks mate!

Umm, did you mean WSS in post-processor? Could you please describe how should I do it?

Cheers
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Old   May 22, 2013, 07:22
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No, I mean use the "Specified Shear" option when you set the wall boundary condition. THen you can set the wall shear stress at that wall as a function of anything you like.
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Old   May 23, 2013, 06:39
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I have got the value of WSS from the equation of Cf, but while inserting it, I am bit confused how to put it here? I have 1 inlet and the rest of the structure is 'wall'. My structure is similar to the cylindrical-shape.

Say I have got the value of WSS of 319.44 N/m2 and how should I put it in this case? WSS won't be same in everywhere of the LV of the heart?
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Old   May 24, 2013, 06:14
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Yes, if you enter the WSS as 319 then it will be 319 everywhere. If you want it to vary then you need to make it a function of something which varies.
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Old   May 27, 2013, 04:53
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I'm still trying it out. Thank you so much!
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