Aerofoils - Why do most CFD outputs give Cp rather than Cl or Cd?!
 

Afternoon all,

As you might have guessed i'm brand new to CFD, so forgive the stupidity of this one;

Why do the majority of CFD outputs you find on, say a google image search, give a coefficient of pressure over an aerofoil rather than something usefull like a coefficient of lift or drag?

If anyone could help iron this for me it would be a great help.

Many thanks for reading the post,

Kay

Plotting lift or drag coeffs over an airfoil would be quite boring and give no further insight. A lift or drag coefficient is an integrated (global) coefficient for a given geometry, whereas a pressure coefficient can be evaluated locally. It only makes sense to do plots of those coefficients for varying geometries, e.g. plot cD vs. an airfoil parameter.

Thats excellent - thanks so much.