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A bit of DIY in progress. A new unifoil

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fluidity
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A bit of DIY in progress. A new unifoil

Postby fluidity » Mon Aug 16, 2021 8:20 am

When the humpback fin tubercle research hit the media it wasn't just Takuma who took note. Many of us did. This is my own experimentation.
Progressive waves out to the wingtips, making the sweep back of a Delta wing less lossy in wingtip vorticies hopefully. At this stage it's just the model I'm working on, then to make a mould off it...
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Re: A bit of DIY in progress. A new unifoil.

Postby Schietwedder » Mon Aug 16, 2021 10:45 am

Interesting! Can you link the paper you are referring to?

http://chevaliertaglang.blogspot.com/20 ... e.html?m=1
There's some R&D for sailboat rudders which main effect seem to be delaying stall/making the transition to stall more gradually.

Are you working on the same principle of delayed stall or something other like more glide/more lift?

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Re: A bit of DIY in progress. A new unifoil.

Postby lederhosen » Mon Aug 16, 2021 12:44 pm

Pretty! What fillament do you print with? Is it foam filled and glassed?
Can’t wait to hear how it rides

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Re: A bit of DIY in progress. A new unifoil

Postby StellaBlu » Mon Aug 16, 2021 3:46 pm

Some of this technology is also present in cycling - particularly wheel design. Perhaps you can leverage some of the research there too. Look at Zipp and Princeton Wheel Works. Im not an engineer, so I don't know how aerodynamics and fluid dynamics differ, but perhaps there is some overlap. Definitely a ton of wind tunnel testing around this concept.

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Re: A bit of DIY in progress. A new unifoil

Postby Jyoder » Mon Aug 16, 2021 3:59 pm

Non-expert here, but from what I remember after reading a bit a while back and making my own bumpy wing, tubercles reduce flow separation at high angles of attack but don’t decrease drag at low angles of attack, in fact they may increase drag at low angles.

https://www.researchgate.net/profile/Fr ... ammals.pdf

https://academic.oup.com/icb/article/51/1/203/636829

The application to hydrofoils is curious because in theory a tubercle wing might pump better and be able to ride slower without stalling.

I don’t recall anything about tubercles helping with tip vortices.

viewtopic.php?f=1&t=2404499&p=1071260&h ... s#p1071260

EDIT: but now I’m diving back in and reading more and looks like it does help with tip vortices too by reducing span-wise flow. Cool


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