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Viscous effects

This video explains how XFLR5 approximates viscosity using the polar outputs from 2D analysis.

Techwinder says on the above video that it does not do the full complex analysis for viscosity. However at this point it looks like it does a pretty good job. I was satisfied yesterday with the outputs I made. Especially considering I’d not read the manual and was just fumbling around. It did a great job of confirming my approximate estimations for Sentach. Looking at the video manual and other text today, it looks like it could do more than accurate enough estimations for my current projects.

As Techwinder states in the forums, it’s not made to just bring in solid geometry from another package and do CFD on it. However it’s focus is foils and it seems to be very fast at assembling foils and doing to calcs. A massive step up from roughing the calcs out by hand. It should be far faster to design future RC wings like Gemot. Gemot was an estimation based on what I new from hands on experience windsurfing and surfing. I actually didn’t really expect it to fly as well as it did on that first proto which crashed into my van.

Although it took several CNC models before I hit Gemot V3. There was only 2D analysis of the 2 Gemot foils using the Dresler software, where I just looked for the best lift : drag ratio for a specific AOA. That became the tip twist for Gemot. It’s still not perfect, but with XFLR5 I may be able to do more accurate mental prototyping with the software.

Still, I wonder if the Autodesk CFD design handles importing the current .stl files for Gemot V3.