# Positioning and size for a Joukowsky Airfoil

Joukowsky transformations are absolutely eluding me because I can't find numerical examples (I have a learning disability and formulas have always made absolutely no sense to me). I'm trying to get an understanding of how to set up a Joukowsky tranformation for an airfoil and it's positioning.

Given a thickness/chord ratio of 12%, Camber of 4%, and angle of attack of 3 degrees.

So far what I've done is trying to get the radius from the thickness/chord ratio. From diagrams it appears that to do that $$\frac{Thickness}{Chord} = \frac{b}{a}$$

Considering that the chord is entire length making the assumption then that $$a = 100$$ $$.12*100 = b$$

This gives the chord of b as $$12$$

to get radius from chord $$\frac{12^2}{12*4}$$

Giving a radius of $$3$$

I've also seen that $$Camber = \frac{\epsilon_i}{2a}$$

Taking again $$a=100$$ and $$camber = 4%$$

$$.04*200 = \epsilon_i = 8$$

This is where I don't know what to do next.

• I’m not sure you really mean “alluding”. Commented Feb 23, 2021 at 15:07
• Thank you. I use both often, but my brain is a bit mushy right now. Commented Feb 23, 2021 at 15:34