Reference area in airfoil geometry

Hello, i have an issue on how to calculate Cl and Cd coefficients in a single airfoil. What is the correct reference area that should be used in order to get the right results? When i put the frontal area the coefficients are too big, and when i put the area from the top view, the numbers are closer to the experimental ones, but still not quite right. Has anyone experienced the same problem?

Hi @perifanas,

Thanks for posting your question!
Just to add something from my side, I would suggest you to check if in your experimental data the reference area considered was the frontal or the wetted area. This is something really common, I mean, I’m not wing specialist but for sure something that I would do in your place would be same setup simulation for the wetted area and then compare the rersults. For your specific CAD:

Please let me know if this helps you.