[WIP] airfoil workbench

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looo
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[WIP] airfoil workbench

Postby looo » Wed Dec 11, 2019 3:25 pm

As I already mentioned somewhere else, I am currently working on an airfoil workbench. I will posts updates in this topic. The work has 3 targets:
1. calibrating/modifying spline-foils to foils given by coordinates
2. optimizing spline foils (reducing drag with libxfoil)
3. interpolation of drag-computation with neural networks (not yet sure if this is a good idea)


1.
The current functionality is mainly the calibration and interactive modification of spline foils (I called them parafoil's -> parametric foils). This tool helps to create good approximations of airfoil coordinates by using a calibration method (least-square method from scipy). I decided to fix the number of poles of a parafoil. This makes the calibration task easier and also will help later on with the wing creation.

phpBB [video]


added nose-tangent and table to modify pole-coordinates and weights:
Peek 2019-12-13 20-31.gif
Peek 2019-12-13 20-31.gif (601.66 KiB) Viewed 2665 times
Last edited by looo on Fri Dec 13, 2019 7:34 pm, edited 1 time in total.
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Joel_graff
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Re: [WIP] airfoil workbench

Postby Joel_graff » Thu Dec 12, 2019 3:11 am

I'd like to include this as a new WB in the 0.19 release notes. Can you post a good description and maybe a nice screenshot either here or in the release notes thread?
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chrisb
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Re: [WIP] airfoil workbench

Postby chrisb » Thu Dec 12, 2019 9:42 am

The release notes thread was rather hard to find. Should it be pinned or moved to Announcments or both?
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Kunda1
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Re: [WIP] airfoil workbench

Postby Kunda1 » Thu Dec 12, 2019 10:39 am

chrisb wrote:
Thu Dec 12, 2019 9:42 am
Should it be pinned or moved to Announcments or both?
:+1:
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chrisb
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Re: [WIP] airfoil workbench

Postby chrisb » Thu Dec 12, 2019 11:13 am

Is this thumb up for pin or move or both :lol: ?
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Kunda1
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Re: [WIP] airfoil workbench

Postby Kunda1 » Thu Dec 12, 2019 3:05 pm

chrisb wrote:
Thu Dec 12, 2019 11:13 am
Is this thumb up for pin or move or both :lol: ?
lol, my vote is to pin it ;)
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looo
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Re: [WIP] airfoil workbench

Postby looo » Thu Dec 12, 2019 3:12 pm

Joel_graff wrote:
Thu Dec 12, 2019 3:11 am
I'd like to include this as a new WB in the 0.19 release notes. Can you post a good description and maybe a nice screenshot either here or in the release notes thread?
I would like to make some progress first, as currently, not much functionality is provided.
chrisb
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Re: [WIP] airfoil workbench

Postby chrisb » Thu Dec 12, 2019 5:17 pm

Kunda1 wrote:
Thu Dec 12, 2019 3:05 pm
lol, my vote is to pin it ;)
I pinned it, we can easily return to the current state by unpinning.
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looo
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Re: [WIP] airfoil workbench

Postby looo » Thu Dec 12, 2019 10:07 pm

I need a solution for finding the leading-edge of an foil given by coordinates. Currently I am using the point with the smallest x-value as the leading-edge. But this is not coorect. I guess a better definition of the leading edge is the intersection of the camber-curve and the airfoil. But I am not sure how to compute this point. Maybe someone has an idea.
leading-edge.png
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microelly2
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Re: [WIP] airfoil workbench

Postby microelly2 » Thu Dec 12, 2019 10:46 pm

What is the definition of the leading edge? I think, I have a feeling,but it is better to have a well defined concept.