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Integration of pressure distribution
Hey, I’m still relatively new to this topic and have now come across a problem that I haven’t been able to solve yet. I wrote a script that integrates the pressure distribution over a profile and calculates the Cl and Cd values from it. If I take 200 Cp values from Qblade, for example, I get exactly the right lift coefficient, but the Cdp value always deviates a little. Shouldn’t I then also get exactly the correct Cdp value? In the script, I first calculate the normal and tangential values and then calculate with the angle of attack in Cl and Cdp. Or is it because of the angle of attack at the end that I don’t have the effective angle of attack? I would be happy to receive an answer.
Best Regards
Hendrik
Hi Hendrik,
while this is an XFoil specific question I do think that the reason probably is that the total drag is not only created by the pressure distribution (Cdp) but also by the skin friction acting on the airfoil through the boundary layer.
BR,
David
