$10,000 bet for downwind faster than the wind - video

[Floradawg]

Once something gets politicized it is a fruitless endeavor to try to have a rational discussion about it. This goes for climate change, covid, border control, you name it. There is some anthropomorphic warming occurring but not nearly at the rate most politically corrupted individuals would have you believe. If they had ever been right it would have already constituted a huge catastrophe. This is MY two cents worth and the truth is climate is so chaotic and the causes of the climate function depend on an incredible number of factors. I don't think anybody can reliably tell you what is going to happen with it over however many years. I've read several books on this subject and I'm convinced there is a whole lot of hokum being dished out.

[nova_robotics]

There is some anthropomorphic warming occurring but not nearly at the rate most politically corrupted individuals would have you believe.

You, me and a hundred other people are in an auditorium. There is also a tiger loose in the auditorium mauling people. What you just said amounts to "Well the tiger is natural and I didn't let the tiger out of the cage." Who cares? Shoot the damn tiger.

We've been reshaping the Earth to better suit us for centuries. I don't see why people are drawing a line in the sand on this particular issue.

[FEM2008]

@ Floradawg: One of those book authors wouldn't happen to be expert Robert Kehoe?

[DIYSwede]

It works, period. "-Because science!"
The wind speed difference from the surface speed powers it - no magic "free energy" involved.

Over 45 years ago, when I was still "young and promising" I read a Scientific American article* on this concept,
but instead it being a wind powered boat going straight into the wind.
It could actually only go into the wind by its very design:

It was supposed to have a pulling propeller in the water, powered by a slanting axle up to an air driven propeller:



I initially thought it just wouldn't work - neither did my buddies, calling it a Perpetual Motion device...

But, I did a proof-of-concept A-framed trimaran, from a few styro blocks, balsa wood and propellers from a hobby shop
(remember those? I. e. the Hobby Shops - not the propellers!)
and ran it half-successfully powered by a decent room fan in the 25 ft long foot washing basin at a gym.
At the start it just drifted downwind, but as its propeller picked up speed it started chugging itself into and upwards into the headwind.

Looked kinda silly, but it sorta worked to the amazement and laughter of my critical friends.

-"It verks!":



Still remember the "The Push-me-pull-you boat" title of the article,
which apparently came from Scientific American [Martin, Sci. Am. 233 (No. 12), 125( 1975)..]
(which I back then occasionally read at the city library),
and I could even found an online analysis of of it this morning (the article, stupid - NOT the library!):
AJP_pushmepullyouboat.pdf



Ah- yes: Some ice boating friends have no problems going 55 mph tacking in a 10 mph wind either.

And Rick even drove into the wind too:

* SciAm article on pg 6 & 7 of this: https://www.jstor.org/stable/2494996...o_tab_contents

PS: Anybody thinking a wind-driven craft could reach over Mach 1 (in ANY direction) is only "not even wrong".

BONUS: Any other intrepid, "free-thinking" HMT:er who also wants to try and prove these simple water tricks:

[Jon]

The irony here is that this demonstration had already been done, over 50 years ago, by an aerodynamics engineer whom nobody has heard of, named Andrew Bauer. The demonstration even included a bet, but for $1, not $10,000. Original paper: https://diqn32j8nouaz.cloudfront.net...-Interface.pdf

Here he is with the craft he built:


0:38 video of it in action:

There's nothing wrong with what Veritasium is doing. It's just interesting how this old demonstration got recycled into the public eye with a famous YouTuber, a Miss America contestant, a "science guy", and a "science communicator".

[jimfols]

The America's Cup boats could probably use a prop if it was wind powered.
This thread may awaken some aerodynamics engineer's history lesson.

[FEM2008]

The America's Cup boats could probably use a prop if it was wind powered.
This thread may awaken some aerodynamics engineer's history lesson.

I could not remember the vertical rotary sail are called (Flettner Rotor Sail), but I ran across this site while looking. Apparently, there is patent on the the design that is now used on "Land Yachts" as seen in the Veratasium video.

ROTARY SAILS WIND TURBINE POWERED BOATS CARS AND SAILING SHIPS

An article regarding Flettner Rotor sails: ROTARY SAILS WIND TURBINE POWERED BOATS CARS AND SAILING SHIPS

[DIYSwede]

I could not remember the vertical rotary sail are called (Flettner Rotor Sail), but I ran across this site while looking.

After almost a century, these Flettner rotors are getting a 2nd chance right now on M/S Viking Grace for the Stockholm-Helsinki cruise line:
https://www.vikingline.com/the-group...ce/rotor-sail/

I seem to remember that this was even mentioned here before: Magnus effect rotary sail propels cruise ship - GIF

[jimfols]

I could not remember the vertical rotary sail are called (Flettner Rotor Sail), but I ran across this site while looking. Apparently, there is patent on the the design that is now used on "Land Yachts" as seen in the Veratasium video.

ROTARY SAILS WIND TURBINE POWERED BOATS CARS AND SAILING SHIPS

An article regarding Flettner Rotor sails: ROTARY SAILS WIND TURBINE POWERED BOATS CARS AND SAILING SHIPS

Thank you for the link.

[Floradawg]

Is 2 billion going to be a problem? How about the who knows how many billion on the earth at that time.