Reference Values for airfoil coefficent calculatio

March 10, 2006, 04:09

Please help me

I have a 2D model of an airfoil, the chord is 6 meters , how do I set the reference values in fluent to have the right force, cd , cl coefficent?

Thank you in advance

March 10, 2006, 16:20

Go to Report->Reference value and if you want to refer to the cord lenght, set Lenght=6m.

smab · November 24, 2011, 01:22

I have my NACA 23015 airfoil(flow speed 36m/s) which has a chord length of 100mm, max thickness 15.05mm,...
after scaling the grid to metres...what should be the reference values for area, length and depth...
i am unable to obtain correct values for Cl and Cd...please help
its very urgent....

husker · November 24, 2011, 03:31

Hi smab,

Why are you repeating the same message in three posts? It makes no sense.

If the chord length is 100 mm then your reference length is 0.1 m and reference area is 0.1m x 1m = 0.1m2.

Another option:

You should scale your airfoil from 100 mm to 1000 mm.
And then you should rescale it to 1 m. Thickness is useless for referencing.
As a result, reference values should be as follows:
Length = 1 m
Area = 1 m2

mohanad07 · November 24, 2011, 04:18

what is the pressure far field?

smab · November 24, 2011, 10:03

thanx...

and sry for the post in 3 different threads...
so what about the depth, what value should i give there...?

March 10, 2006, 04:09	Reference Values for airfoil coefficent calculatio	#1
Patrizio Guest Posts: n/a	Please help me I have a 2D model of an airfoil, the chord is 6 meters , how do I set the reference values in fluent to have the right force, cd , cl coefficent? Thank you in advance

March 10, 2006, 16:20	Re: Reference Values for airfoil coefficent calcul	#2
nick Guest Posts: n/a	Go to Report->Reference value and if you want to refer to the cord lenght, set Lenght=6m.

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November 24, 2011, 01:22		#3
smab New Member Shibin Mohamed Join Date: Nov 2011 Posts: 8 Rep Power: 15	I have my NACA 23015 airfoil(flow speed 36m/s) which has a chord length of 100mm, max thickness 15.05mm,... after scaling the grid to metres...what should be the reference values for area, length and depth... i am unable to obtain correct values for Cl and Cd...please help its very urgent....

November 24, 2011, 03:31		#4
husker Member Join Date: Mar 2009 Posts: 85 Rep Power: 17	Hi smab, Why are you repeating the same message in three posts? It makes no sense. If the chord length is 100 mm then your reference length is 0.1 m and reference area is 0.1m x 1m = 0.1m2. Another option: You should scale your airfoil from 100 mm to 1000 mm. And then you should rescale it to 1 m. Thickness is useless for referencing. As a result, reference values should be as follows: Length = 1 m Area = 1 m2

November 24, 2011, 04:18		#5
mohanad07 New Member mohanad hussien Join Date: Nov 2011 Posts: 2 Rep Power: 0	what is the pressure far field?

November 24, 2011, 10:03		#6
smab New Member Shibin Mohamed Join Date: Nov 2011 Posts: 8 Rep Power: 15	thanx... and sry for the post in 3 different threads... so what about the depth, what value should i give there...?