Are strings the main cause of aerodynamic drag?

Discussion in 'Badminton Stringing Techniques & Tools' started by Maklike Tier, May 19, 2013.

1. Maklike Tier Regular Member

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I'm one of those weird people that constantly think about racket design, and I have this theory that the frame design only contributes minimally to drag, and that the real cause of drag is the strings.

So the natural step in this process, is to think about how to reduce the amount of strings to test the theory.

Not being a stringer, I got one of my 80 hole prototypes and drew out a design that eliminates 10 strings, making it a 16 x 20 pattern.

Is something like this possible? I'm guessing that having more horizontal strings would mean that the tension would have to be dropped on them proportionally more than the vertical ones?

Would this pattern result in some strange and potentially bad frame distortion?

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2. visor Regular Member

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interesting... since you're at it, why not reduce a few cross strings too to balance the frame tension and cut down on more air drag?

also, time for you to switch to zm62 strings...

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3. Maklike Tier Regular Member

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I was hoping to get some custom strings made in an aerofoil shape

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4. Mark A Regular Member

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A racket contains roughly 9.5 m of string. Given a diameter of, say, 0.70 mm, the total frontal area of the strings is 66.5 cm^2 (or 10.30 in^2). (String intersections can be subtracted, but they're pretty much negligible - no more than 2 cm^2).

The area of a badminton racket head is around 360 cm^2. This means that roughly one fifth of the head is "blocked off" by the strings!

Edit: subtract the loops outside the frame as well... probably down to a one-sixth loss.

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Last edited: May 19, 2013
5. visor Regular Member

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No wonder I can swing an unstrung racket at the store faster than I can play with a strung one on court...

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6. Shinichi Regular Member

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should send your design to Yonex and see if they like it

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7. Maklike Tier Regular Member

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Frontal area is only part of the aero equation, Mark.

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not gonna work. string crossings will naturally twist the string to the least aero profile.

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agreed.

aerodynamic drag increases with more boundary layer. and the cylindrical shape of the string has a pretty high drag.

while the racket frame of modern design are designed to be more aero.

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10. Mark A Regular Member

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Unless it's some kind of isotropic aerofoil... in which case, badminton strings should be the least of our concerns.

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11. RedShuttle Regular Member

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Maybe someone can make a clamp to clamp the strings into the right aerodynamic profile. You may have to re-clamp after each game though.

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12. Maklike Tier Regular Member

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I was joking about making the actual string aero foil shaped, geez.

So anyway, Stringers.....is it possible to string like this?

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13. Mark A Regular Member

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I think we were all running with it, mate.

I don't see why not - surely it would leave the frame under less stress (but there's a slight imbalance between the top and bottom of the pattern, not that it should matter).

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14. Shinichi Regular Member

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then it will be called the maklike string pattern

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15. Jacob mm Regular Member

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I think it would be better to do a 16X18, to get more equal stress.

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