Results N0012 with y+<65 or y+<15 ?

ferranpm · February 4, 2011, 12:05

Hello!

My test:
Profil NACA0012
Re=1M
alpha=15°
K-Omega SST with Trans. Flow

I read that when i use K-omega theory, i should have an y+<1. With my first mesh, I had an yplus < 65, and the profil is not in stall.

I use the "adapt" funtion to reduce the yplus. I used max. yplus=1, min. yplus=0. Then I iterate one more time, and now the profil is in stall (more accuracy?) and the yplus was < 15.

Which result has more accuracy? Can I use K-omega with yplus more than 1, or maybe should I use K-Epsylon?

Thank you!!
Ferran PM

ferranpm · February 5, 2011, 06:06

Hello again,

I read about K-Omega SST and with Trans. flow I need y+<1. Should I suppose that my results are not so good enough?

Thank you

Ferran

DoHander · February 5, 2011, 18:07

y+ between 1 and 30 typically means bad results in Fluent, so your simulation with y+ < 15 is not to be trusted.

Do

February 4, 2011, 12:05	Results N0012 with y+<65 or y+<15 ?	#1
ferranpm New Member Join Date: Jun 2009 Posts: 6 Rep Power: 16	Hello! My test: Profil NACA0012 Re=1M alpha=15° K-Omega SST with Trans. Flow I read that when i use K-omega theory, i should have an y+<1. With my first mesh, I had an yplus < 65, and the profil is not in stall. I use the "adapt" funtion to reduce the yplus. I used max. yplus=1, min. yplus=0. Then I iterate one more time, and now the profil is in stall (more accuracy?) and the yplus was < 15. Which result has more accuracy? Can I use K-omega with yplus more than 1, or maybe should I use K-Epsylon? Thank you!! Ferran PM

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February 5, 2011, 06:06		#2
ferranpm New Member Join Date: Jun 2009 Posts: 6 Rep Power: 16	Hello again, I read about K-Omega SST and with Trans. flow I need y+<1. Should I suppose that my results are not so good enough? Thank you Ferran

February 5, 2011, 18:07		#3
DoHander Senior Member Join Date: Nov 2009 Posts: 411 Rep Power: 19	y+ between 1 and 30 typically means bad results in Fluent, so your simulation with y+ < 15 is not to be trusted. Do