I hope it is okay to ask these kinds of questions here, since it is not specifically about the software and more about airfoils and CFD in general.
I’m working on a ultra light airplane project and is currently searching for suitible airfoils.
One of the airfoils that has caught my eye is the DAE-11 airfoil, which seems to be suitible for the slow flying airplane that I’m designing.
On airfoiltools.com the maximum L/D-ratio is at least 135.8 (angle of attack is 7.25 degrees and Ncrit=9). But when I look at this page: LINK the L/D is “only” 47.05 (at an angle of attack at -0.5 degrees).
In my preliminary simulations of tha airfoil in at 7.25 degrees AOA, here on simscale, I get nothing close to a L/D ratio of 135.8.
- Why is there a large difference in maximum L/D-ratio between the two sources?
- Is there any other good way of finding reliable data for L/D-ratios on airfoils?