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December 19, 2010, 02:44 |
k-e model
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#1 |
New Member
Join Date: Nov 2010
Posts: 7
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Hi. I want to make a simulation for a airfoil for i solute it with FLUENT. I must use the k-e turbulent model but i do not know how i make the mesh near the wall of airfoil. I have read that the Y plus of first cell must be within 30-300 for standard wall function. However, How can i compute the Y length of cells for i make the mesh arround the foil (NACA0012),and also ,I want some tutorials about ernal flow around airfoil or cylinder with Reynolds number at nearly 50000. Thanks |
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December 19, 2010, 04:36 |
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#2 | |
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Alexey
Join Date: May 2009
Location: St.Petersburg, Russia
Posts: 23
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Quote:
Then calculate friction stress and friction velocity Then we have where is the kinematic viscosity Last edited by ignat; December 19, 2010 at 06:07. |
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December 24, 2010, 03:55 |
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#3 |
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Join Date: Nov 2010
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thanks,ignat
now ,i had done some examples by k-e model ,y+=0.0001m,Angle of Attack is 12(re=50000,the chord length is 1m),but from the result ,i can't find the shedding vortex,may i have your email ? i have some details to talk with you,ok? looking forward to your reply .merry christmas |
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December 24, 2010, 07:27 |
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#4 |
New Member
Alexey
Join Date: May 2009
Location: St.Petersburg, Russia
Posts: 23
Rep Power: 17 |
y+ is dimensionless parameter. What does it mean "m"?
May be it is dimension value? Optimal y+ near the wall is about 1 (dimensionless!) for calculation without wall function and 10-100 for calculation with wall functions. But never 0.0001! Did you estimate friction velocity u* for your case? I am not expert in aerodynamics but i think shedding vortex does not obligatory occur. It depends on many circumstances. regards. |
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k-e y plus |
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