Hi, I try to analyze different kind of airfoils for formula students car. To get forces coefficients, Simscale want me to set a reference length for my object. I have read below link. I understood the reference area but I did’t get the reference length. Exactly which distance is that (point from where to where)?

I also curious about how it effect the result. In drag or lift coefficient formula, there is reference area. However the reference length is not included in formula. By saying formula I mean these formulas:

Drag Coefficient:

https://www.grc.nasa.gov/WWW/K-12/airplane/dragco.html