Braided tether drag reduction

Engineering
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Hi all,

I would like to share a work in progress I have started a few months ago, to try to reduce tether drag. My main focus was underwater, but it might be of interest for drag reduction in the air as well.

I have shared the work on my blog, so I won’t go into details in this post. Here is one of the posts about trying to create a tether by braiding directly the expected low drag cross section. It is only one part of the problem.

I am currently doing an internship (till mid-september) in a braiding workshop using old wood braiding machines from the 19th able to do special braids. Here are a few examples. If you have questions on the subject, do not hesitate (I might have to check if some information are confidential).

1 Like
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Very cool @batlabat

One of my brothers and his wife got into braiding and coded a really good braiding design website from braiding geometry maths

https://craftdesignonline.com/

This was a couple decades ago at least … Proper old web.

Storm Dunker had a paper on the aerodynamic efficiency of different braiding patterns

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The world is so small ! I have been using their website (best one with a working 3D simulator) and was in touch with him last year, when they had troubles with some bots.

I have started a python library balled braidpy, but I would like to share some tools for interactive use online, so I should get more in touch with him !

Thanks, I found the paper from Storm Dunker (I probably had seen it long before !).

While looking for it, I also found another related one discussing the drag of different ropes and effect of latex coating (better with finer braiding than coarse, and latex improving performance for coarse rope, not so much for rope which are already slick). I already noticed with my small traction kites, that used lines (fluffing and pilling) are dragging more.