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How to calculate Y+( Yplus)

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Old   January 7, 2011, 10:47
Smile How to calculate Y+( Yplus)
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mohammad
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Hi everybody.
I'm working on a wind turbine.
I want to set the first node position ( yplsu) for teh blade.my question is that how should I calculate Yplus?
I have found the formula
DY=L*(DY+)*SQRT(80)*Re^(-13/14)
as a rule of thumb to calculate Yplus.

But, as soon as I get the results and I see the value of Yplus in the CFX_postresult, those values really differ from what I set in ICEM.

Do you still think the above equation for calculation of (DY+) is trustworthy and enough? If the resulted Yplus' are severely different form the given Yplus, Should I go back to ICEM file and rearrange my mesh or just when the above equation is satisfied it's enough?

TNX
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Old   January 7, 2011, 14:41
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Aamer Shahzad
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Hello Mohammad...


type "viscous grid spacing calculator" on google and you will find an interface which calculates y pluss for you based on certain inputs. please check if it helps.
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Old   January 8, 2011, 12:55
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Mahbub Islam
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Try this link.

http://geolab.larc.nasa.gov/APPS/YPlus/
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Old   January 12, 2011, 00:23
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mohammad
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Hi...
Thank you guys for your help...
Results of that link are the almost the same as the proposed equation in Ansys Help Manual...
For future readers, I must say that according to my experience, the equation is good but It's necessary that after applying this equation and calculating the YPLUS you must check the value of YPLUS in CFX-POSTP_ROCESS and check whether you need more changes or not...I mean as an essential and extra check check CFX-POSTP_ROCESS.

Best wishes
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