... I sent the link to a friend and he has questions! He generously allows to take the film at face value and not presume a battery or something. I must admit...
Dave Howorth
Dave.Howorth@...
Dec 3, 2006 6:57 pm
380
... The stroboscope effect makes that difficult whenever something rotating is shown on film. Once the rotation speed is such that a propeller blade (or wheel...
Hello Robert, Thanks for your very detailed answer. ... Yes, both my friend and I understand this. Nonetheless, it does make it impossible to observe the...
Dave Howorth
Dave.Howorth@...
Dec 4, 2006 9:42 pm
382
... That's about how I see it too - the prop is very much a model aircraft propeller, not a wind mill propeller, which naturally is twisted the other way...
I had an article in catalyst with all the details of the wind car. Also one on how to build the propeller. The wheels do turn the propeller, and the ...
Kudos to you, Jack, for such a superbly simple and elegant demonstration. I, for one, am humbled and inspired by the buzz you have created here and on...
Dave Howorth schrieb: ... This was I expect Jim Wilkinson's wind turbine catamaran. Jim was kind enough to treat me to a ride on it once. He has since moved to...
G'day, Jim's was not the only cruising cat with a windmill on the east coast of England at that time. I had a 9.4m dia 3 bladed turbine on my 9m Iroquois cat...
... I never saw the boat Rob, but you did show me your turbine blades. Thanks for the data. ... I think this was a strong point of Jim's: he had a prop I...
The timid (or sane :-) wore motorcycle helmets on Jim's boat... Cheers, Theo Yeah, and he had the net under the blades as added protection. Plus, his was...
... Sorry, I made a wrong guess at the reason behind the question. ... One extra complexity is that for sailing directly upwind, you need a wind turbine and...
I believe that Bauer's cart (www.dcss.org/bauer_cart.jpg) had a variable pitch propeller/turbine, thus could windmill at low speeds as well as upwind, and also...
... Thanks for that. I've now managed to find it. It's in #23; I don't know how I missed it. I think it would be well worthwhile to post it online; ideally...
Dave Howorth
Dave.Howorth@...
Dec 5, 2006 11:39 pm
392
... That was probably why we thought we saw so much of the boat then! We were seeing double. Cheers, Dave...
Going directly upwind, driven by a propeller, and powered by a windmill, will be very difficult. But for the moment we'll disallow hull resistance and friction...
Tord Eriksson wrote on 06 December 2006 13:34 ... "Eppur si muove" ("and yet it moves") (G Galilei, 1633 allegedly) ... Power is not the problem. What you have...
Er... didn't someone run a Bembridge Redwing with a windmill/water propeller set up in the '60s? [No, it was I believe an autogyro - Moderator] ... From: Tord...
... Hello, Scuse me, I was out for a while... about my hapa: - The one in the video was possibly "popped out" when the kite have no more power (over-luffing)...
From Tord's posting, I deduce he believes that windmilling upwind is theoretical. I hear this quite often. Tord (and others sharing this belief); please...
... Somewhere in a recent Catalyst was a description of a very simple model. It was a lightweight stick with ballast and a small propeller at one end, and a...
You need to look at this webpage http://www.main.org/polycosmos/silicbar/sailscrw.htm Peter Worsley ... From: robertbiegler To: ayrs@yahoogroups.com Sent:...
Tord Eriksson wrote: "Going directly upwind, driven by a propeller, and powered by a windmill, will be very difficult. But for the moment we'll disallow hull...
This little device was suggested--and built--by David Santos, a kinetic sculptor (?) from somewhere near Auston, TX. I used to have photos and a short video of...
Just thought you might be interested to hear about a lecture I attended yesterday evening at Falmouth, UK, set up by RINA and IMarest. The lecture was given by...
G,day, I cannot remember the exact efficiencies, but from memory the windmill was much less efficient than 80% (100% would mean the air behind it was still, ie...
I dunno how knowledgeable, but I can offer a little bit more data. The Betz limit won't allow any turbine blade (or sail) to extract more than about 58% of the...
There is a small model of a wind powered catamaran at the Nathanial Herrshoff Museum in Rhode Island. It has a single long shaft, with an air propeller at...
Lord Brabazon. Apparently it worked as well as the sails of the time, but he stopped experimenting when he lost control and damaged some boats. The blades of...
