CORed
Penultimate Amazing
In the unlikely event that you ever actually show your cart, unless you also give detailed instructions on how to reproduce it (as spork did with the treadmill carts), I will call fake.
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Merged DDWFTTW in a “Real” Wind
- Thread starter ynot
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In the unlikely event that you ever actually show your cart, unless you also give detailed instructions on how to reproduce it (as spork did with the treadmill carts), I will call fake.
In JavaProp you can modify your design in a number of ways. One way is by changing the beta angle of each station of the blade. This would make it easy to model a variable pitch prop. You then have it analyze the modified design and you get a similar table of off-design performance parameters for any chosen pitch.
Would you be kind enough to repeat it? I have never seen this.
I was just thinking that if you change the propeller's pitch, depending on the wind speed and your speed, you could then do better than would appear possible from a simple calculation like mine that is based on figures for a fixed pitch propeller.
Is it easy to tell, while piloting the Blackbird, how best to adjust the propeller pitch?
In a perfectly steady wind it would be relatively easy to do. When the wind is changing I'm never really certain I've got it right. Mostly, I feel the acceleration and try to max out the speed read to 1/10th mph on the GPS.
But the result does not agree with the trial. How do you explain that?
You can do what you like.
I wouldn't hold my breath waiting for Humber!
Expect the expected when it comes to Humber's tales. He still owes me a "Top Secret" cart that climbs treadmills.
I expect never to see this promise fulfilled.
There's a phrase to describe this kind of behavior where I come from.
WingGrins
Expect the expected when it comes to Humber's tales. He still owes me a "Top Secret" cart that climbs treadmills.
I expect never to see this promise fulfilled.
There's a phrase to describe this kind of behavior where I come from.
WingGrins
You're welcome. Here is another interesting project that attempts to break the 500m speed sailing record:
http://verneyyachts.com/index.htm
They recently decided to add extra outriggers and a second crew member laying on one of them (at 65mph!):
http://verneyyachts.com/v-44-albatross-images.htm
I wonder if JB is gonna build himself a sidecar for the BB.
Subduction Zone
Muse
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Were those designed to sail in only one direction at high speed, A. T.?
Originally it was a symmetrical design that flipped over by 90deg to change tack. The plan was to use it also for longer distance records, that require maneuvering. This is still possible but with the extra crewman as ballast on only one side they seem to concentrate on a one way straight 500m tack for now.
There's a phrase to describe this kind of behavior where I come from.
WingGrins
Hog callin'?
It takes some engineering knowledge to see that it is mechanically realizable, but only general knowledge to see that Spork's claim for the TM must be false. Post away, as the cart sits over there.
Every once in a while Humber tries to reboot the discussion by posting one of these reset type claims which ignore all previous logic. I am always a little disappointing when Humber resorts to trolling 101, instead of his usual master classes.
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Although I know better than to think you would actually answer, I will ask anyway to show any newcomers your MO. Could you write down your definition of ddw?
We know what NALSA's definition was. Everyone but the H's think they are the most qualified folks in the world to come up with the definition, but I am still curious to find out what yours is. I am expecting you will not write it down because it will then become obvious to everyone what your game is.
We know that you conveniently can't understand (or more likely you do understand it but still claim you don't) the TM equivalence which provides perfect 0 degree ddw. I know that your definition of ddw condition cannot be met in the real world, because that is in fact, the very condition you required when you created it. I just think you should explicitly state it so everyone will know.
Okay, here's the $100K version. I will wager $100K US against your $1000.
Send me the cart and the $1000, and an engineer that I choose will determine the winner. I will send you $100K if you win. I will return the cart regardless of the winner.
Your own math shows it as clearly as any I have ever seen. I find that hilarious. Thank you.
Actually, I don't think anyone has shown the math for the region below wind speed where bluff drag drops off below the necessary force to keep accelerating.
Largely because only people like spork or H'eth would even have access to the math to calculate thrust in negative winds, and even then it is way too messy to bother with, especially after showing the cart actually has enough thrust to do it in real life.
Yes, I should not have pulled the quote out of the discussion re below WS. I was referring to his >WS math. I, like any non-troll, could care less how the cart gets to WS.
No, you put up the money and secure it, and the testing is done by an independent engineering bureau, as I proposed. It would not be in their interests to have their name linked with a hoax. On the other hand, "an engineer of you choice" is likely to be incompetent and biased.
Your "math" has shot itself down. It predicts enormous forces, that change with cart speed, but the constant acceleration of the cart seen in the trial says small and constant force.
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