Cl too high

Project Support
1

Hey guys,

After countless hours of trying to get my mesh to work I finally got one I was happy with. But after having a look at the force reports I noticed, that my Cl value is way too high (about -9) while downforce is at 110N. I dont know, if its because I calculated 2 Force-Co plots (1 with Cla, so reference area=1 and one with the actual projected area of the wing, measured out of cad). The Cla value (0.8) looks fine, but the one with the actual reference area seems too high. All the Convergence plots are looking good too, besides maybe the residuals plot. I checked everything, and cant find my mistake.

Thank you.

2

Hello Team StrohmUndSoehne

Based on my experience a CLA of 0.8 is realistic, as well as a 110N of Downforce for 15m/s.
Also based on the values provided, the CL also is calculated correctly.
It’s just a fact that stand-alone wings with ground effect are very potent, with respect to the frontal reference area.

Without any further reference data, I’d say that the result seems realistic.

Best regards
Sebastian

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