first of all, thanks for the great XFLR5 tutorials, man! second, in 7:49 you say rightaway that it is not a very nice foil. how were you able to say that? and when you're dealing with a unknown/new airfoil modification, what analysis would you run to test it and see if it improved or worsened you airfoil?? Thanks!
Wow paulinho! I see that you havi duvidas... I sugest you conversations to Cataboy! He knows all foils by heart and ajudar you a entender better!! ت ☛☛ 🇧🇷🇧🇷
Hi Techwinder, THX a lot for great tutorials so far. At 3:04 the blue graph is shown. What does it sstand for? The y-column shows Q/vinf which means surface-velocity/??? And x column shows x/c? Is this this the length of the foil? like 0,3 is 30 percent of the length? Thx a lot!!!
@@techwinder Sorry set the wrong time. Talking about 3:07 where the curve is blue and crosses the x-axis at exactly 0,5 (50%). Why is this shape like this? Is the lower part again the bottom surface and the upper part the top surface?
@@SoaringExperience Yes that's correct, lower part=bottom and upper=top. The original XFoil doesn't display it like this, but this layout makes it much easier to process afterwards.
Hi Techwinder ; I want to modify my airfoil as such manner that the maximum of L/D ratio , coincides with my cruise attack angle . How you please and idea how to do this with inverse foil design ? Thanks
First thanks for the great tutos, they help a lot. when i change to xfoil inverse Design they just give the foil with the flap and i cant change it ? Even if i put the selected Foil in Oppoints and polar view it gets changed. Could you help me please
Yes, that's one reason. When performing a direct analysis, XFoil likes smooth panel distributions, with higher densities at the leading edge. The repanel command does just that. The other reason is that the full inverse method creates foils with 255 points, which is unnecessarily large, and will make for longer analysis times afterwards.
thanks for the fast reply! I'm designing the aerodynamic package for a Formula SAE front wing, and these videos will surely help me get started in the foil profiles :)
Great
great job and great tutorial!
first of all, thanks for the great XFLR5 tutorials, man! second, in 7:49 you say rightaway that it is not a very nice foil. how were you able to say that? and when you're dealing with a unknown/new airfoil modification, what analysis would you run to test it and see if it improved or worsened you airfoil??
Thanks!
Wow paulinho! I see that you havi duvidas... I sugest you conversations to Cataboy! He knows all foils by heart and ajudar you a entender better!! ت ☛☛ 🇧🇷🇧🇷
Hi Techwinder,
THX a lot for great tutorials so far.
At 3:04 the blue graph is shown. What does it sstand for? The y-column shows Q/vinf which means surface-velocity/??? And x column shows x/c? Is this this the length of the foil? like 0,3 is 30 percent of the length?
Thx a lot!!!
The curves are the velocity profiles on the top and bottom surfaces. The red one is for the original foil, and the blue one is for the modified foil.
@@techwinder Sorry set the wrong time. Talking about 3:07 where the curve is blue and crosses the x-axis at exactly 0,5 (50%). Why is this shape like this? Is the lower part again the bottom surface and the upper part the top surface?
@@SoaringExperience Yes that's correct, lower part=bottom and upper=top. The original XFoil doesn't display it like this, but this layout makes it much easier to process afterwards.
@@techwinder Thanks a lot. I am just confused why this curve/spline hits the x-axis at 0,5 and make looks a bit like a square sinus function
Hi Techwinder ;
I want to modify my airfoil as such manner that the maximum of L/D ratio , coincides with my cruise attack angle . How you please and idea how to do this with inverse foil design ?
Thanks
hi
Why you have done the modifcation to the foil at min 8:50 ?
ie why you increase its thickness
it's just visual; scaling up the vertical axis doesnt' change the foil's geometry
First thanks for the great tutos, they help a lot. when i change to xfoil inverse Design they just give the foil with the flap and i cant change it ? Even if i put the selected Foil in Oppoints and polar view it gets changed. Could you help me please
thank you, great Tutorial :)
How to change the aoa for a given Cl ?
Great tutorials! I don't get why we have to repanel, does it help in the convergence?
Yes, that's one reason. When performing a direct analysis, XFoil likes smooth panel distributions, with higher densities at the leading edge. The repanel command does just that.
The other reason is that the full inverse method creates foils with 255 points, which is unnecessarily large, and will make for longer analysis times afterwards.
thanks for the fast reply! I'm designing the aerodynamic package for a Formula SAE front wing, and these videos will surely help me get started in the foil profiles :)
Could someone help me please? What method does xfrl5 use to do the inverse design?