taiguy wrote:I haven't seen any information that would corroborate edt's claim.UKSurf wrote:Why does a 10m kite have 4x the power of a 5m in your first chart? I would think it would have 2x approx. also the power seems to be increasing with the power of 4 not power of 2 for wind speed. We need Bill Hanson to confirm these figures before they are used to purchase a quiver
Power increases with respect with the square of the area and cube of the windspeed. But please have Bill come and give us all a short course
taiguy think about it for a second, it is ridiculous to go with cubed.
If you go with v^3, then if you fly a 12 meter kite in 20 knots, in 30 knots you need a 3.5 meter kite.
If you go with v^2, then if you fly a 12 meter kite in 20 knots, in 30 knots you need a 5 meter kite.
You can't just look at wikipedia without noting that when they give these figures of v^3 is it not for a kite it is for a turbine. The turbine spins faster the higher the wind. This means it extracts one additional factor of v. If instead of a turbine you are measuring the amount of force pushed back against a car it's 1/2 p v^2 Cd A go look it up, that's because unlike a wind turbine the car doesn't spin around in circles it just sits there in the air.
Anyway, just crank out a few numbers and example kite sizes it's pretty easy to see right away v^3 makes absolutely no sense.
Also kite size and rider weight scales linearly. Only wind speed scales as square for figuring kite size.
So a 20 meter kite pulls twice as hard as a 10 meter kite, and a 200 pound rider needs twice the kite size as a 100 pound rider.