negative drag
gdew...@gmail.com
I'm happy to announce that the drag generated by a vehicle may be used
by a windmill as if it was wind. This of course creates extra drag but
this drag is partially shared with the rider.
We thus have a free energy situation on our hands here. :-)
Drag is limited by the size of the vehicle. If any amount of this drag
is turned into propulsion then that percentage (just) wont be
available for slowing the vehicle down. It's not-there anymore.
I have illustrated the concept here.
http://gabydewilde.googlepages.com/negative-drag
Let me think what you hear ok?
Regards,
gaby de wilde
Eric Gisse
> Hello all,
>
> I'm happy to announce that the drag generated by a vehicle may be used
> by a windmill as if it was wind. This of course creates extra drag but
> this drag is partially shared with the rider.
>
> We thus have a free energy situation on our hands here. :-)
Do you actually believe this?
Elmo
Of course what would really happen is that the wind would initially blow
you backwards slightly, the backwards motion causing the fan to rotate
backwards which would cause you to go backwards faster, causing the fan
to rotate faster and so on. The effect would snowball until you were
going backwards at the speed of sound.
elmo
gdew...@gmail.com
> On Dec 11, 9:19 pm, "gdewi...@gmail.com" <gdewi...@gmail.com> wrote:
>
> > Hello all,
>
> > I'm happy to announce that the drag generated by a vehicle may be used
> > by a windmill as if it was wind. This of course creates extra drag but
> > this drag is partially shared with the rider.
>
> > We thus have a free energy situation on our hands here. :-)
>
> Do you actually believe this?
>
No it was a joke, I obviously mean wind energy. But you can only "use"
drag one time. If you put a propeller in front of a bicycle the
propeller will obviously break part of the drag. This "drag" will then
be "lost" from the face of the cyclist. Just like when you put up a
windscreen or have some one cycle in front of you.
Or do you think the same drag can be fully applied twice? One time to
the propeller and another time onto the rider? 2 times the same force?
gdew...@gmail.com
Vince Morgan
"Elmo" <E...@mo.com> wrote in message
news:475f8d82$1...@news.peopletelecom.com.au...
> gdew...@gmail.com wrote:
> > Hello all,
> >
> > I'm happy to announce that the drag generated by a vehicle may be used
> > by a windmill as if it was wind. This of course creates extra drag but
> > this drag is partially shared with the rider.
And that means what?
If the drag is hared with the rider, the rider shares that with the car, so
the drag is on the car anyway.
> > Drag is limited by the size of the vehicle. If any amount of this drag
> > is turned into propulsion then that percentage (just) wont be
> > available for slowing the vehicle down. It's not-there anymore.
Perhaps you mean that a portion of the drag energy has been converted into
forward propulsion. However, putting a fan into the airstream "increases"
the drag in the first place, so the energy produced may help to alleviate
that "extra" drag you just created.
> Of course what would really happen is that the wind would initially blow
> you backwards slightly, the backwards motion causing the fan to rotate
Errr, what wind? The car isn't moving, so where did this wind come from?
> backwards which would cause you to go backwards faster, causing the fan
> to rotate faster and so on. The effect would snowball until you were
> going backwards at the speed of sound.
Nope. The fan is in "that" wind, which is coming from the front,
apparently. Do you realize you are suggesting that the wind will blow the
car backwards so fast that it will be going backwards faster than the wind
is blowing? Otherwise the fan keeps going as if the car were moving
forward, does it not?.
Perhaps you could extend this to fans blowing onto sails on boats. Or, a
turbine in the water that generates a current to run the boats electric
motor thus keeping it moving forward to drive the turbine.
I imagine free energy, if it's possible, should take just a tad more
thought.
Vince
gdew...@gmail.com
On Dec 12, 9:59 am, "Vince Morgan" <vinharAtHereoptusnet.com.au>
wrote:
> Perhaps you mean that a portion of the drag energy has been converted into
> forward propulsion.
yes, you do know what I mean.
>However, putting a fan into the airstream "increases" the drag in the first place,
Yes, but you cant keep increasing the drag without increasing the
surface. Like for example inside a car there is no wind.
>so the energy produced may help to alleviate
> that "extra" drag you just created.
>
Exactly.
If we would stack 2 windmills on the front of a bike the second one
will not generate as much drag as the first one. Of course that means
it wont spin as fast as the first one either.
In that same way the rider is not subjected to the full amount of drag
because the propeller has pre-accelerated some of the air.
If there is any drag on the propeller anything behind it is suffering
below maximum drag. It of course makes a world of difference if you
just try to push the air away or if you use it for propulsion.
You get the picture.
I also made a picture to show you can sail close to straight up the
wind. It means there is still much room for improvement. One should
imagine the combination of both in case that isn't obvious still. :-)
The wind will be the propulsion together with the drag but some drag
is also reduced in my design, you can see the vertical rotors push the
wind to the sides. This is creating a vacuum at the front, they also
push the wind inwards at the rear, this creates pressure behind the
rider.
The total is the sum of the parts.
Elmo
Land yachts have already been invented I'm afraid.
Elmo
Leo Lichtman
Question: what effect did that have on my net worth?
A Muzi
That's not even among the more humorous and entertaining 'perpetual
motion' follies. Get rid of the silly red-line animations and draw in a
few complex mechanical distractions maybe?
--
Andrew Muzi
www.yellowjersey.org
Open every day since 1 April, 1971
Uncle Al
>
> Hello all,
>
> I'm happy to announce that the drag generated by a vehicle may be used
> by a windmill as if it was wind. This of course creates extra drag but
> this drag is partially shared with the rider.
>
> We thus have a free energy situation on our hands here. :-)
1) "Barbarella" and the ice sled.
2) Idiot
3) You won't get to top Jane Fonda, either.
4) Idiot.
--
Uncle Al
http://www.mazepath.com/uncleal/
(Toxic URL! Unsafe for children and most mammals)
http://www.mazepath.com/uncleal/lajos.htm#a2
gdew...@gmail.com
I'm happy to announce that the drag generated by a vehicle may be used
by a windmill as if it was wind. This of course creates extra drag but
this drag is partially shared with the rider.
We thus have a free energy situation on our hands here. :-)
Drag is limited by the size of the vehicle. If any amount of this drag
is turned into propulsion then that percentage (just) wont be
available for slowing the vehicle down. It's not-there anymore.
I have illustrated the concept here.
http://gabydewilde.googlepages.com/negative-drag
Let me think what you hear ok?
Regards,
gaby de wilde
Bill Sornson
gdew...@gmail.com
gdew...@gmail.com
wrote:
> I took the change out of my left pocket and put it in my right pocket.
> Question: what effect did that have on my net worth?
Hello Leo,
Lets say there is a big hole in your left pocket.
Drag presented by the rider is not useful for anything, it's an
annoyance.
The surface area of the rider and the fan placed in series is not the
same thing as when placed parallel. The drag per cm2 has it's
maximum.
It's like a screen blocking the wind. You know how a wind screen
works.
It's just like cycling behind someone or driving behind a truck.
The rotors make drag but this drag is not slowing the vehicle down.
The rider is riding in the slipstream of the windmill.
five thousand years ago, the Egyptians made sailboats.
In 1493 Giacomo Caprotti designed a bicycle.
In 1790 Monsieur Sivrac made the first bicycle.
In 50 Hero of Alexandria described A wind wheel operating an organ
In 700 windmills were used in Iran.
Everything has already been done. They are more then worthy
technologies.
If I put the windmill on the bike. You want to pretend it stops
working??
Be specific, what stops working. The bike or the windmill?
They don't just continue to work but they actually compliment another.
Just look at the spammers trying to obfuscate the topic. That should
say enough.
:-)
R.H. Allen
> On Dec 12, 6:03 pm, "Leo Lichtman" <l.licht...@worldnet.att.net>
> wrote:
>> I took the change out of my left pocket and put it in my right pocket.
>> Question: what effect did that have on my net worth?
>
> Hello Leo,
>
> Lets say there is a big hole in your left pocket.
>
> Drag presented by the rider is not useful for anything, it's an
> annoyance.
>
> The surface area of the rider and the fan placed in series is not the
> same thing as when placed parallel. The drag per cm2 has it's
> maximum.
>
> It's like a screen blocking the wind. You know how a wind screen
> works.
A wind screen spares the person behind it the annoyance of having to
face into a stiff wind, but it creates a lot of drag.
> It's just like cycling behind someone or driving behind a truck.
Is it, now? Try attaching a garage door to the front of your car and
tell me if it improves your gas mileage the way drafting behind a truck
would. (Hint: It won't, because the drag on the garage door will be
transmitted to your car -- unlike a drafting situation, where the drag
on the truck in front of you is *not* transmitted to your car.)
> The rotors make drag but this drag is not slowing the vehicle down.
It most certainly is, unless the windmill is not attached to the bicycle.
> The rider is riding in the slipstream of the windmill.
But the drag on the windmill acts on the bicycle, and since the rider is
mechanically connected to the bicycle (i.e., sitting on it), it slows
the rider down too. The windmill might make it a little more comfortable
for the rider, the way a windshield would, but it won't help the rider
go any faster.
> five thousand years ago, the Egyptians made sailboats.
>
> In 1493 Giacomo Caprotti designed a bicycle.
>
> In 1790 Monsieur Sivrac made the first bicycle.
>
> In 50 Hero of Alexandria described A wind wheel operating an organ
>
> In 700 windmills were used in Iran.
>
> Everything has already been done.
I don't know about that, but I DO know that you're not the first person
to come up with this idea. It's been done to death (though as a concept
it has its pedagogical uses, namely demonstrating the laws of
thermodynamics).
> If I put the windmill on the bike. You want to pretend it stops
> working??
>
> Be specific, what stops working. The bike or the windmill?
>
> They don't just continue to work but they actually compliment another.
As another person already pointed out, if you put a windmill on the
front of a bicycle it will increase the drag on the bicycle. (For
instance, the air pressure behind the windmill will be less than in
front of it, creating a net force opposing the motion of the bicycle.)
The best you could hope to do is use some of the energy from the fan to
offset the effects of the drag. You will not, however, be able to offset
all of the drag you add, so the net effect will be that the bicyclist
will have to pedal harder to maintain the same speed as without the
windmill.
If you don't believe me, try your idea out in a wind tunnel. I guarantee
the drag coefficient increases enough to negate the energy you extract
from the airstream and then some.
> Just look at the spammers trying to obfuscate the topic. That should
> say enough.
Oh, that's an *old* chestnut -- if enough people say it doesn't work,
why then they're covering something up and it MUST work, right?
A Muzi
>> I took the change out of my left pocket and put it in my right pocket.
>> Question: what effect did that have on my net worth?
I'll put some cash on a bet that anything you add to your bicycle's
frontal area reduces speed for any given constant effort. Magic fans,
ducts, rotors, ouija boards, windscreens and sails included. Name it.
How's $100 sound to you??
Although the Patent Office won't accept applications for perpetual
motion devices, you'd have bragging rights and my $100 if you succeed.
p.s. you intended 'complement'
A Muzi
>>> I took the change out of my left pocket and put it in my right pocket.
>>> Question: what effect did that have on my net worth?
> gdew...@gmail.com wrote:
>> Lets say there is a big hole in your left pocket.
>> Drag presented by the rider is not useful for anything, it's an
>> annoyance.
>> The surface area of the rider and the fan placed in series is not the
>> same thing as when placed parallel. The drag per cm2 has it's
>> maximum.
>> It's like a screen blocking the wind. You know how a wind screen
>> works.
R.H. Allen wrote:
> A wind screen spares the person behind it the annoyance of having to
> face into a stiff wind, but it creates a lot of drag.
> gdew...@gmail.com wrote:
>> It's just like cycling behind someone or driving behind a truck.
R.H. Allen wrote:
> Is it, now? Try attaching a garage door to the front of your car and
> tell me if it improves your gas mileage the way drafting behind a truck
> would. (Hint: It won't, because the drag on the garage door will be
> transmitted to your car -- unlike a drafting situation, where the drag
> on the truck in front of you is *not* transmitted to your car.)
> gdew...@gmail.com wrote:
>> The rotors make drag but this drag is not slowing the vehicle down.
R.H. Allen wrote:
> It most certainly is, unless the windmill is not attached to the bicycle.
> gdew...@gmail.com wrote:
>> The rider is riding in the slipstream of the windmill.
R.H. Allen wrote:
> But the drag on the windmill acts on the bicycle, and since the rider is
> mechanically connected to the bicycle (i.e., sitting on it), it slows
> the rider down too. The windmill might make it a little more comfortable
> for the rider, the way a windshield would, but it won't help the rider
> go any faster.
> gdew...@gmail.com wrote:
>> five thousand years ago, the Egyptians made sailboats.
>> In 1493 Giacomo Caprotti designed a bicycle.
>> In 1790 Monsieur Sivrac made the first bicycle.
>> In 50 Hero of Alexandria described A wind wheel operating an organ
>> In 700 windmills were used in Iran.
>> Everything has already been done.
R.H. Allen wrote:
> I don't know about that, but I DO know that you're not the first person
> to come up with this idea. It's been done to death (though as a concept
> it has its pedagogical uses, namely demonstrating the laws of
> thermodynamics).
> gdew...@gmail.com wrote:
>> If I put the windmill on the bike. You want to pretend it stops
>> working??
>> Be specific, what stops working. The bike or the windmill?
>> They don't just continue to work but they actually compliment another.
R.H. Allen wrote:
> As another person already pointed out, if you put a windmill on the
> front of a bicycle it will increase the drag on the bicycle. (For
> instance, the air pressure behind the windmill will be less than in
> front of it, creating a net force opposing the motion of the bicycle.)
> The best you could hope to do is use some of the energy from the fan to
> offset the effects of the drag. You will not, however, be able to offset
> all of the drag you add, so the net effect will be that the bicyclist
> will have to pedal harder to maintain the same speed as without the
> windmill.
> If you don't believe me, try your idea out in a wind tunnel. I guarantee
> the drag coefficient increases enough to negate the energy you extract
> from the airstream and then some.
> gdew...@gmail.com wrote:
>> Just look at the spammers trying to obfuscate the topic. That should
>> say enough.
R.H. Allen wrote:
> Oh, that's an *old* chestnut -- if enough people say it doesn't work,
> why then they're covering something up and it MUST work, right?
Every kid who had a Molor Products "Cosmic Whirl" just _knew_ it made
the bike go faster:
http://www.deltiology.com/00000images/cosmic.gif
(discontinued product AFAIK)
Leo Lichtman
<gdew...@gmail.com> wrote: clip) It's just like cycling behind someone or
driving behind a truck. (clip)
^^^^^^^^^^^^^^^^^^
Then please do this thought experiment and report the results:
Mount your bicycle behind a truck, so that when you pedal you push the
truck. ;-) I don't know why I am continuing in this argument--every
proposal to achieve perpectual motion can be put away with this simple
statement: "It's against the law."
tadchem
If *you* had to power an array of windmills with your own legs
pedaling the bike, you wouldn't think that the energy was "free".
Tom Davidson
Richmond, VA
gdew...@gmail.com
wrote:
> I don't know why I am continuing in this argument-
Hello Leo,
You posting has words in it but there is not one argument Leo
Lichtman.
I'm reading nonsense and you are making me read it.
http://gabydewilde.googlepages.com/negative-drag
gabydewilde - negative drag
Werehatrack
I'd swear I saw a contraption like that in an old 16mm film about
loony inventions that people came up with back around World War One.
TANSTAAFL! Particularly in physics.
--
My email address is antispammed; pull WEEDS if replying via e-mail.
Typoes are not a bug, they're a feature.
Words processed in a facility that contains nuts.
gdew...@gmail.com
On Dec 13, 12:55 am, tadchem <tadc...@comcast.net> wrote:
> If *you* had to power an array of windmills with your own legs
> pedaling the bike, you wouldn't think that the energy was "free".
>
A windmill with pedals?
wow........
ehhhhhh.... Well Tom Davidson, it takes a lot but I'm speechless!
http://en.wikipedia.org/wiki/Windmill
"A windmill is a machine that is powered by the energy of the wind."
http://www.answers.com/windmill&r=67
"A machine that runs on the energy generated by a wheel of adjustable
blades or slats rotated by the wind."
but ok I guess you have 6 percent oxygen in the atmosphere I cant
blame you for mind farting in public.
Could you please in stead of picturing me in your intentionally
dismissive unworkable test setup try to think towards the goal of the
invention?
I claim a windmill spins by the power of the wind. DUH!!
I further claim diverting drag to propulsion removes that drag. You
wont get 1:1 but you wont have the full drag remaining behind the
rotors.
You claim you can magically increase the drag without increasing the
surface area.
And you claim to be able to increase the drag by using a rotating
windmill that doesn't generate propulsion.
NOW THAT'S MAGIC MAN!!
You are to increase drag so much in fact that both propulsion from
drag and propulsion from wind stop working at any speed of either wind
or bike.
You explain how the windmill cant possibly do any work and how the
wind replenishing it self back to it's full force right behind the
rotor.
This is such extreme nonsense that I think you know it is nonsense.
But please explain away I beg of you.
How does this magic of yours work?
______
Elmo
A Muzi
>> I don't know why I am continuing in this argument-
gdew...@gmail.com wrote:
> You posting has words in it but there is not one argument Leo
> Lichtman.
> I'm reading nonsense and you are making me read it.
Here's what you snipped:
<gdew...@gmail.com> wrote: (clip)
It's just like cycling behind someone or driving behind a truck. (clip)
"Leo Lichtman" <l.licht...@worldnet.att.net> wrote:
Then please do this thought experiment and report the results:
Mount your bicycle behind a truck, so that when you pedal you push the
truck. ;-) I don't know why I am continuing in this argument--every
proposal to achieve perpectual motion can be put away with this simple
statement: "It's against the law."
If Leo's responses to your troll were incomprehensible to you, the
problem is not with Leo, nor the rest of us.
Vince Morgan
> gdew...@gmail.com wrote:
> > Hello Tom Davidson,
> >
> > On Dec 13, 12:55 am, tadchem <tadc...@comcast.net> wrote:
> >> If *you* had to power an array of windmills with your own legs
> >> pedaling the bike, you wouldn't think that the energy was "free".
Wow! That is amazing. So easy and simple. Makes you wonder how so many
clever and resourcefull persons have missed this energy source previously.
The implications are enormous! The engines in airplanes are completely
redundant, and always have been apparently. If you put a propeller on your
head and jump from an airplane you could end up in orbit before you had a
chance to rip it off! Perhaps you could go for the "Unpowered flight around
the world" record if there is one, using my propeller-head idea. It would
be an absolute head turner (especialy if the bearing suddenly siezed) and
the publicity would virtualy gaurantee further funds for devellopment.
However, being so easily achieved you had better hurry before someone else
does it, and the skies become filled with propeller-heads to the point of
dangerous congestion.
I'll have another look at that video, but first I need to put some timber up
to give the nails a reason to be there.
Vince
Tim McNamara
<78e9def8-4dd1-4b15...@s8g2000prg.googlegroups.com>,
"gdew...@gmail.com" <gdew...@gmail.com> wrote:
> How does this magic of yours work?
That's the question we have been asking you. You haven't answered it in
any sensible way yet. At this point I can only conclude that you are a
troll.
NoEinstein
> Hello all,
>
> I'm happy to announce that the drag generated by a vehicle may be used
> by a windmill as if it was wind. This of course creates extra drag but
> this drag is partially shared with the rider.
>
> We thus have a free energy situation on our hands here. :-)
>
> Drag is limited by the size of the vehicle. If any amount of this drag
> is turned into propulsion then that percentage (just) wont be
> available for slowing the vehicle down. It's not-there anymore.
>
> I have illustrated the concept here.
>
> http://gabydewilde.googlepages.com/negative-drag
>
> Let me think what you hear ok?
>
>
> gaby de wilde
Of course, if cars drove on a circular track, one right after the
other, the "breeze" would be like a very large fan. But why use a gas-
guzzling fan to power a fan? Where is the energy advantage there?
But if you happened to live beside a freeway, you could erect a
windmill and "sap" the wind energy to power your computer, etc. Don't
brag about it as "science", just do it and laugh! -- NoEinstein --
gdew...@gmail.com
by a windmill as if it was wind. This of course creates extra drag but
this drag is partially shared with the rider.
We thus have a free energy situation on our hands here. :-)
Drag is limited by the size of the vehicle. If any amount of this drag
is turned into propulsion then that percentage (just) wont be
available for slowing the vehicle down. It's not-there anymore.
I have illustrated the concept here.
http://gabydewilde.googlepages.com/negative-drag
Let me think what you hear ok?
Regards,
gaby de wilde
gdew...@gmail.com
by a windmill as if it was wind. This of course creates extra drag but
this drag is partially shared with the rider.
We thus have a free energy situation on our hands here. :-)
Drag is limited by the size of the vehicle. If any amount of this drag
is turned into propulsion then that percentage (just) wont be
available for slowing the vehicle down. It's not-there anymore.
I have illustrated the concept here.
http://gabydewilde.googlepages.com/negative-drag
Let me think what you hear ok?
Regards,
gaby de wilde
datakoll
CWatters
> Of course what would really happen is that the wind would initially blow
> you backwards slightly, the backwards motion causing the fan to rotate
> backwards which would cause you to go backwards faster, causing the fan
> to rotate faster and so on. The effect would snowball until you were
> going backwards at the speed of sound.
>
> elmo
One of these can sail dead into wind....
http://i.treehugger.com/images/2007-2-21/Windmill-Sailboat.jpg
CWatters
> gdew...@gmail.com wrote:
> Here is one on Utube.
> http://www.youtube.com/watch?v=aJpdWHFqHm0
>
> Elmo
This one is bigger...
http://i.treehugger.com/images/2007-2-21/Windmill-Sailboat.jpg
peter
>
> Every kid who had a Molor Products "Cosmic Whirl" just _knew_ it made
> the bike go faster:http://www.deltiology.com/00000images/cosmic.gif
> (discontinued product AFAIK)
Of course no one here, incl. gaby, ever claimed that the Cosmic Whirl
(CW) would make a bicycle faster. But if it's mounted in front of the
rider in such a way that it doesn't add any frontal area then it won't
make the bike have any more wind resistance either. I.e. there's added
drag on the CW but correspondingly less drag on the rider right behind
it so the sum remains the same. So making the CW spin takes nothing
away from the speed of the bike.
If you now use the energy of its spinning to provide mechanical energy
it would be possible, at least in principle, to make the bike just a
bit faster. In practice I doubt that you could extract enough energy
to make up for the added weight and assorted frictional losses, but
what's proposed is not any kind of perpetual motion or other device
that is prohibited by basic conservation principles. Adding a fairing
to reduce the wind resistance is clearly far easier and more
effective.
A Muzi
That was funny once. Your post seems to have achieved the perpetual
motion you're finding elusive in the real word.
carl...@comcast.net
wrote:
>On Dec 12, 2:34 pm, A Muzi <a...@yellowjersey.org> wrote:
>>
>> Every kid who had a Molor Products "Cosmic Whirl" just _knew_ it made
>> the bike go faster:http://www.deltiology.com/00000images/cosmic.gif
>> (discontinued product AFAIK)
>
>Of course no one here, incl. gaby, ever claimed that the Cosmic Whirl
>(CW) would make a bicycle faster. But if it's mounted in front of the
>rider in such a way that it doesn't add any frontal area then it won't
>make the bike have any more wind resistance either. I.e. there's added
>drag on the CW but correspondingly less drag on the rider right behind
>it so the sum remains the same. So making the CW spin takes nothing
>away from the speed of the bike.
Dear Peter,
You're falling into the same perpetual motion mistake.
Where does the power come from to spin the Cosmic Whirl?
The rider's legs, of course.
Remember the three laws of thermodynamics, easy enough even for laymen
when described in terms of gambling against the devil in hell.
1) You can't win. (You never get more energy than you start with. You
can't get 101 watts out of a 100 watt system.)
2) You can't break even. (You always lose some energy. You can't even
get 100 watts out of that 100 watt system--frictional losses are
losses.)
3) You can't even quit. (Just sitting there, a closed system tends
toward entropy.)
You _can_ improve the aerodynamics to reduce drag, often in a
non-intuitive fashion, but the propeller isn't likely to function that
way--it will likely just create more chaotic turbulence and increase
drag.
The classic example is the trip wire on the face of a sphere, which
seems as if it ought to increase drag, but actually reduces drag by
clothing the sphere with a thin layer of turbulent air that in crude
terms greases the trailing part of the sphere.
The effect is shown in the two famous photos at the bottom of this
page:
http://www.princeton.edu/~asmits/Bicycle_web/blunt.html
The flow is from left to right. The left-hand sphere has no trip wire
and shows a large flare of turbulence, corresponding to drag. The
right-hand sphere has a trip wire (just a wire circle stuck on the
left side of the sphere) that creates a thin boundary layer of
turbulence that "greases" the surface and greatly reduces drag.
The same principle is used on golf balls. No matter which way the ball
flies and spins, the dimples provide the tiny layer of turbulence to
reduce the drag.
A propeller, on the other hand, doesn't provide a thin layer of useful
turbulence. It just kicks up a chaotic storm--which requires more
energy than smooth flow.
The ideal aerodynamic effect is a tapered double-ended knitting needle
that pushes as little air as possible gently and slowly outward and
then lets the same air close again just as gently and slowly, leaving
no eddies or turbulence behind--any turbulence means that power has
been wasted accelerating the mass of the air, not the vehicle.
That's why canoes and kayaks are double-ended--the pointy front end
parts the water gently, and the pointy back end lets the water close
gently, leaving scarcely any wake. Put a propeller on the front or
back, and it would just add to the drag, spinning the water into
useless swirls.
That said, I believe that a Cosmic Whirl would indeed make a bicycle
faster, but Einstein died before he could complete the proof. :-)
Cheers,
Carl Fogel
artmichalek
That only works if you believe that drag is only a function of frontal
area. Even if we approximate the windmill as a flat plate, it's going
to have a drag coefficient approximately ten times higher than the
cyclist drafting behind it. A windmill will generate less drag than a
flat plate, but the more drag it creates the more efficient it is. It
doesn't matter if the windmill is connected to the drivetrain. The
power that's turning the windmill is additional power that you've
already put into the system in order to move the bicycle and generate
air flow. Under the ideal, lossless case you'll break even, but
you'll never get anything out of it. What's being proposed is
prohibited by basic conservation principles. You simply cannot get
more energy out of a system than you put into it.
Leo Lichtman
"peter" wrote: (clip) But if it's mounted in front of the
> rider in such a way that it doesn't add any frontal area then it won't
> make the bike have any more wind resistance either. I.e. there's added
> drag on the CW but correspondingly less drag on the rider right behind
> it so the sum remains the same. So making the CW spin takes nothing
> away from the speed of the bike.
If it were not for the friction in the bearing, that might be true.
However, if it disrupts the lines of flow, it probably would increase the
drag.
^^^^^^^^^^^^^^^^^
If you now use the energy of its spinning to provide mechanical energy
> it would be possible, at least in principle, to make the bike just a
> bit faster.
This is completely wrong. Any power that is drawn from the spinning
propeller will increase its drag. It's the law. There is no free lunch.
Do you think a generator can run a headlight without taking power from the
rider?
gdew...@gmail.com
> That was funny once. Your post seems to have achieved the perpetual
> motion you're finding elusive in the real word.
> --
ok thanks for the feedback, I will try a bit harder as to say
nothing. :-)
gdew...@gmail.com
wrote:
> Wow! That is amazing. So easy and simple. Makes you wonder how so many
> clever and resourcefull persons have missed this energy source previously.
I read quite a bit of old patents. I'm always amazed how resourceful
people use to be. Humans are like way unpredictable. It actually is
quite a sad topic. The majority of patents didn't have an application
in their days. Their inventors did advance our tech but we gave them
shit for reward. And loads of shit. We continue to do so till this
very day.
They evidently had so much shit it's safe to say the current
scientific mindset is the embodiment of this very horse manure. Oh how
hard we laugh at the things we so desperately need? Laughing is very
healthy but ignorant laughter could be fatal up to a global scale.
To force your own ignorance down the throat of others is a whole
different chapter.
Who are you to call the World of war craft and Briney Spears
generation creative and resourceful?
Are you making a joke here?
"...have missed this energy source.."
Oh, if only that was all "they" had missed nothing would be wrong.
It's how they keep on intentionally missing things. You cant really
call it "missing something" because missing something suggest some
kind of looking was done. Specially the more knowledgeable people try
avoid anything involving a gain in energy.
I cant wait for people to claim this isn't so. That would be
hilarious!
If you want more power out of a windmill you need to make it bigger.
If you want more drag out of a bicycle you need to make it bigger.
You can generate more power by using bigger blades on a windmill.
You can increase drag by increasing the frontal surface area of a
bicycle.
If the area making contact with the moving air is increased drag will
increase.
If the area making contact with the moving air is replaced drag will
not increase.
I cant find ways to justify using energy for an aeroelastic face
fluttering effect. What is with this desire to have this facial
fluttering vector?
The kind mixed with rain is specially nice. ROFL!
Yes, I'm afraid it's exactly as funny as you make it out to be.
:-)
R.H. Allen
>
> I cant wait for people to claim this isn't so. That would be
> hilarious!
There's one way that's guaranteed to shut everybody up: Build it and
prove that you get a net energy gain. Until then, you can hardly blame
us for choosing to believe laws of physics that we have seen
successfully tested time and time again over some guy in a newsgroup who
is all talk and no action.
> If the area making contact with the moving air is increased drag will
> increase.
> If the area making contact with the moving air is replaced drag will
> not increase.
Not necessarily. Yes, drag is proportional to frontal area, but it is
also proportional to drag coefficient. You can change the drag
coefficient without changing the frontal area. In fact, with a
sufficient reduction in drag coefficient you can *increase* frontal area
and still *reduce* drag. However, adding a windmill to the front of an
object is guaranteed to increase the drag coefficient regardless of what
it does (or doesn't do) to frontal area.
datakoll
due due due due due due please allow me...
http://www.washingtonpost.com/wp-dyn/content/article/2007/12/13/AR2007121300966.html
peter
> On Thu, 13 Dec 2007 11:13:59 -0800 (PST), peter <prath...@comcast.net>
> wrote:
>
> >On Dec 12, 2:34 pm, A Muzi <a...@yellowjersey.org> wrote:
>
> >> Every kid who had a Molor Products "Cosmic Whirl" just _knew_ it made
> >> the bike go faster:http://www.deltiology.com/00000images/cosmic.gif
> >> (discontinued product AFAIK)
>
> >Of course no one here, incl. gaby, ever claimed that the Cosmic Whirl
> >(CW) would make a bicycle faster. But if it's mounted in front of the
> >rider in such a way that it doesn't add any frontal area then it won't
> >make the bike have any more wind resistance either. I.e. there's added
> >drag on the CW but correspondingly less drag on the rider right behind
> >it so the sum remains the same. So making the CW spin takes nothing
> >away from the speed of the bike.
>
> Dear Peter,
>
> You're falling into the same perpetual motion mistake.
>
> Where does the power come from to spin the Cosmic Whirl?
>
> The rider's legs, of course.
Obviously, and again, this is by no means a perpetual motion machine
since no one is claiming that the bicycle will somehow move by itself
- just that in principle a tiny bit of the energy that would normally
go into overcoming wind resistance anyway can instead by harnessed to
give back a bit of useful work. That's not perpetual motion - just a
minor reduction in the efective drag from air resistance.
>
> Remember the three laws of thermodynamics, easy enough even for laymen
> when described in terms of gambling against the devil in hell.
>
> 1) You can't win. (You never get more energy than you start with. You
> can't get 101 watts out of a 100 watt system.)
>
> 2) You can't break even. (You always lose some energy. You can't even
> get 100 watts out of that 100 watt system--frictional losses are
> losses.)
>
> 3) You can't even quit. (Just sitting there, a closed system tends
> toward entropy.)
I've had plenty of thermodynamics courses and the suggested proposal
does nothing to violate the laws of thermo or even the distorted
version you give above.
>
> You _can_ improve the aerodynamics to reduce drag, often in a
> non-intuitive fashion, but the propeller isn't likely to function that
> way--it will likely just create more chaotic turbulence and increase
> drag.
Nothing I wrote above indicated that the propellor was reducing the
drag - note that I specifically indicated that the total drag remains
the same. There's no particular reason why a small windmill located
so that it is directly in front of the rider needs to increase the
total drag force.
Non-relevant golf ball example deleted.
> The ideal aerodynamic effect is a tapered double-ended knitting needle
> that pushes as little air as possible gently and slowly outward and
> then lets the same air close again just as gently and slowly, leaving
> no eddies or turbulence behind--any turbulence means that power has
> been wasted accelerating the mass of the air, not the vehicle.
>
> That's why canoes and kayaks are double-ended--the pointy front end
> parts the water gently, and the pointy back end lets the water close
> gently, leaving scarcely any wake. Put a propeller on the front or
> back, and it would just add to the drag, spinning the water into
> useless swirls.
A more relevant example would be the streamlined shapes used by the
HPV cycles. And, as I stated before, adding such a fairing would be
both easier and more effective than the windmill suggestion. But
we're not talking about adding the windmill to a properly faired and
streamlined bicycle, but instead to one with a decidedly non-
aerodynamic upright cyclist. That cyclist is already leaving lots of
turbulent air swirls in his wake.
peter
My car has a coefficient of drag of 0.35, and it has a much more
streamlined shape than a regular upright cyclist. Where did your
factor of 10 (implying a Cd of 0.1) come from? Figures I've seen for
normal cyclists have been more around 0.6 or 0.7. As long as the
windmill is right in front of the cyclist and smaller than him then I
don't see why it couldn't be designed so that it doesn't increase the
coefficient of drag - it might even be possible to reduce it a bit.
> A windmill will generate less drag than a
> flat plate, but the more drag it creates the more efficient it is. It
> doesn't matter if the windmill is connected to the drivetrain. The
> power that's turning the windmill is additional power that you've
> already put into the system in order to move the bicycle and generate
> air flow.
It's not additional - it's power that the cyclist is already providing
to overcome air resistance even if he didn't have the little windmill
in front.
> Under the ideal, lossless case you'll break even, but
> you'll never get anything out of it. What's being proposed is
> prohibited by basic conservation principles. You simply cannot get
> more energy out of a system than you put into it.
And no one here has proposed any system which would do that. The
bicyclist is still the source of all the power that is propelling the
bike.
But energy is being wasted to air resistance and turned into heat and
turbulence of the air in the rider's wake. There's no conservation
law that says you can't instead use a portion of that energy in a more
useful way.
As I said before, I don't think the proposal is at all practical. But
objections based on thermodynamic and conservation law principles are
not valid against it because it doesn't violate these.
datakoll
Kid at the library started a conversation on communicating with "alien
civilizations." Whaddya think about it,? he asked after devolving his
idea.
I said, The "aliens" are so far away, the communicating wave form is
lost over the distance. What is needed is what you see: stars. Blank
out a star's emission or particular wavelength band: blink blink blink
zzzzzzzzzzzzzzzzzzzzzzzzzzzzz blink blink blink zzzzzzzzzzzzzzzzzzzz
blink.... And what hath God wrought?
A D cell flashlight isn't enough.
He was speechless.
?
datakoll
Uncle Al's quote of the day:
Innovation is not the product of logical thought, even though the
final product is tied to a logical structure.
gdew...@gmail.com
http://www.canosoarus.com/08LSRbicycle/LSR%20Bike01.htm
http://images.google.com/images?q=bicycle+speed+records
On Dec 13, 7:32 am, Elmo <E...@mo.com> wrote:
http://www.youtube.com/watch?v=aJpdWHFqHm0
On Dec 13, 7:46 pm, "CWatters" <colin.watt...@turnersoak.plus.com>
wrote:
"One of these can sail dead into wind"
http://i.treehugger.com/images/2007-2-21/Windmill-Sailboat.jpg
On Dec 13, 7:48 pm, "CWatters" <colin.watt...@turnersoak.plus.com>
wrote:
"This one is bigger"
http://i.treehugger.com/images/2007-2-21/Windmill-Sailboat.jpg
On October 27, 2006 "http://cyclesantamonica.blogspot.com" wrote:
"This is a video clip of the finish of the Nissan One Hour Challenge,
in which Fast Freddie Markham, Olympic cyclist, riding a bicycle of
his own design, achieves world record speed of over 60 miles per
hour."
http://blog.360.yahoo.com/Factuurexpress?p=6842
"Forever Electric car ( by wind force generator)"
http://blog.360.yahoo.com/factuurexpress?p=6802
I put the links here.
http://gabydewilde.googlepages.com/negative-drag-suggested-reading
The practical designs will need to evolve but that can only happen if
we know there is useful energy there for the taking.
http://sketchup.google.com/3dwarehouse/search?q=wind+powered+bicycle&btnG=Search&styp=m
gdew...@gmail.com
> That's not even among the more humorous and entertaining 'perpetual
> motion' follies. Get rid of the silly red-line animations and draw in a
> few complex mechanical distractions maybe?
>
This good enough for a start?
http://sketchup.google.com/3dwarehouse/search?q=wind+powered+bicycle&btnG=Search&styp=m
Vince Morgan
"CWatters" <colin....@turnersoak.plus.com> wrote in message
news:13m2vdu...@corp.supernews.com...
Vince
datakoll
more, excuse multiple posts asa the product of a cluttered mind.
the internet bloomed in time when I began looking to integrate "my
science" into the general scientific body of knowledge. And what did I
find?
NOTHING
almost nothing. not a van roof mounted toliet seat anywhere.
I did find several, a handful of self publicizing fellow travelers who
were following traditonal paths selling you know CD's, herbal and non
herbal remedies, various self help or self destruction manuals-the
usual.
Irene Pepperberg and Alex were a remarkable exception
BUT no applicable science.
another indication of finding something useful and original.
then Google tuned in. Imagining several clots of Googlers in Mt View
software sifting thru cyberspace to the leading edge is not difficult,
right? So when im would get THERE in cyberspace, Google would
sometimes be waiting for me like Selden himself to say hi and welcome
to this platform.
But my idea, which is kinda like your idea, requires a normal energy
source: THE SUN
That's what Newton said from his cold stone farm house: IT'S THE SUN
STUPID.
So my functional explaination of reality, taken to it's logical
conclusion rattle rattle rattle is to degrade the Universe expansion a
bit and place that degrade into a battery.
I assume this leads to eternal life.
read Ann Rand.
carl...@comcast.net
wrote:
[snip]
>Obviously, and again, this is by no means a perpetual motion machine
>since no one is claiming that the bicycle will somehow move by itself
>- just that in principle a tiny bit of the energy that would normally
>go into overcoming wind resistance anyway can instead by harnessed to
>give back a bit of useful work.
[snip]
Dear Peter,
Think about that some more.
Basically, you end up arguing that adding more and more tiny
propellers to the front of a bicycle will somehow make it go faster
and faster because they're "harnessing" something.
More power is required to move the bicycle _and_ spin the propeller
than can be recovered from propeller.
It's about the same as arguing that the store loses a dime on every
widget that they sell, but they make it up through increased volume.
Cheers,
Carl Fogel
gdew...@gmail.com
> Basically, you end up arguing that adding more and more tiny
> propellers to the front of a bicycle will somehow make it go faster
> and faster because they're "harnessing" something.
>
Yes, I think you almost understand it now.
> More power is required to move the bicycle _and_ spin the propeller
> than can be recovered from propeller.
>
Yes, exactly right. But you are forgetting something here.
If we can replace say 10% of the drag by say a 50% regenerative
system.
Then the rider suffers 5% less drag.
The remaining 95% of the drag is suffered by the rider and it
decelerates the vehicle.
On Dec 14, 1:10 am, "Vince Morgan" <vinharAtHereoptusnet.com.au>
wrote:
> "CWatters" <colin.watt...@turnersoak.plus.com> wrote in message
> > One of these can sail dead into wind....
>
> >http://i.treehugger.com/images/2007-2-21/Windmill-Sailboat.jpg
>
> It can? How is that possible?
> Vince
yes
Leo Lichtman
bicycle with NO INCREASE IN POWER INPUT. I wound up with a propeller that
had no moving parts, and whose blades were shaped like a fairing.
peter
> On Thu, 13 Dec 2007 14:09:44 -0800 (PST), peter <prath...@comcast.net>
> wrote:
>
> [snip]
>
> >Obviously, and again, this is by no means a perpetual motion machine
> >since no one is claiming that the bicycle will somehow move by itself
> >- just that in principle a tiny bit of the energy that would normally
> >go into overcoming wind resistance anyway can instead by harnessed to
> >give back a bit of useful work.
>
> [snip]
>
> Dear Peter,
>
> Think about that some more.
>
> Basically, you end up arguing that adding more and more tiny
> propellers to the front of a bicycle will somehow make it go faster
> and faster because they're "harnessing" something.
Not at all. I'm arguing that if you start with something that's about
as aerodynamic as a slightly rounded brick (i.e. the typical upright
cyclist), that it isn't all that hard to place something smaller right
in front of it that will 1) at least not make the aerodynamics any
worse, and 2) allow some small, but non-zero amount of energy to be
extracted from the windstream.
>
> More power is required to move the bicycle _and_ spin the propeller
> than can be recovered from propeller.
Sure, that's why the cyclist has to keep pedaling - no one here is
denying that. But in principle he might be able to pedal just a
little less vigorously for a given speed than if he had the same air
resistance and didn't get any energy from the propellor.
For example, the object we put out in front of the cyclist could be in
the shape of an aerodynamic nose cone. Let's say a fairing of that
type cuts his wind resistance by 20%. Now we add some bearings and
little fins to the nose cone so it'll start rotating in the wind. The
fins will obviously add back some air resistance, but by keeping them
small we can make sure that the overall result is still no worse than
the unfaired cyclist. Any energy we can extract from the spinning
cone and use for propulsion is now a net plus if we're only interested
in power needed to overcome air resistance.
Now does this make any practical sense? No. The fairing without fins
is undoubtedly a better way to go and far less complex. And for
overall utility it's probably best to stick with the original unfaired
bike for less weight and greater convenience.
>
> It's about the same as arguing that the store loses a dime on every
> widget that they sell, but they make it up through increased volume.
Analogies are only useful to the extent that the situations are truly
analogous.
carl...@comcast.net
wrote:
[snip]
>Now does this make any practical sense? No.
[snip]
Dear Peter,
You're getting closer.
You can extract useful energy by sticking a propeller into an
airstream to use onboard, just as you can extract useful energy
through a generator's roller to run a light.
You cannot, however, extract energy that is useful for propelling the
vehicle forward _faster_ because you lose more than you gain.
Cheers,
Carl Fogel
gdew...@gmail.com
wrote:
> I sat down and designed a propeller that would increase the speed of a
> bicycle with NO INCREASE IN POWER INPUT. I wound up with a propeller that
> had no moving parts, and whose blades were shaped like a fairing.
Me to.
A slight spiral shape should generate centrifugal force depending on
the speed and drag. Then have a recumbent slide down the vacuum in the
center of a vortex. It's that what Victor Schauberger calls light air.
But to smoothly pedal the air up to speed the bike would become much
to long.
That's why one would use a propeller I think. Or a rotating cone. :-)
I doubt efficiently gearing windmills to the wheels a bit.
It would be better to use the wind to further enhance the air flow.
Tom Sherman
> ...
> Now does this make any practical sense? No. The fairing without fins
> is undoubtedly a better way to go and far less complex. And for
> overall utility it's probably best to stick with the original unfaired
In the case of a long-wheelbase recumbent, the performance increase of a
front fairing is well worth the weight and expense (not to mention the
side benefit of greater comfort in cold and wet conditions).
--
Tom Sherman - Holstein-Friesland Bovinia
"Localized intense suction such as tornadoes is created when temperature
differences are high enough between meeting air masses, and can impart
excessive energy onto a cyclist." - Randy Schlitter
datakoll
> On Thu, 13 Dec 2007 17:56:16 -0800 (PST), peter <prath...@comcast.net>
> wrote:
>
> [snip]
>
> >Now does this make any practical sense? No.
>
> [snip]
>
> Dear Peter,
>
> You're getting closer.
>
> You can extract useful energy by sticking a propeller into an
> airstream to use onboard, just as you can extract useful energy
> through a generator's roller to run a light.
>
> You cannot, however, extract energy that is useful for propelling the
> vehicle forward _faster_ because you lose more than you gain.
>
> Cheers,
>
> Carl Fogel
proposing an expanding universe converts energy to dark matter?
the dark matter linking worm holes to seperate but connected
universes?
is that what you're trying to pull on us Fogel?
well, you'll not get away with it.
Tom Sherman
> ...
> My car has a coefficient of drag of 0.35, and it has a much more
> streamlined shape than a regular upright cyclist. Where did your
> factor of 10 (implying a Cd of 0.1) come from? Figures I've seen for
Here is what a bicycle with a coefficient of drag of slightly less than
0.1 looks like:
<http://www.ent.ohiou.edu/~et181/hpv/Andrea_64.7mph.jpg>. (Yes, she is
pedaling the bicycle in excess of 64 mph without wind or gravitational
assistance.)
Tom Sherman
>
> I'll put some cash on a bet that anything you add to your bicycle's
> frontal area reduces speed for any given constant effort. Magic fans,
> ducts, rotors, ouija boards, windscreens and sails included. Name it.
> How's $100 sound to you??...
Not a good bet. For example, the Varna Diablo II [1] has more frontal
area with the fairing on than off. Yet, Sam Whittingham's reported top
speed on an unfaired lowracer similar to the Diablo chassis is in the
low 40 mph range, while he has gone a verified 81 mph on the faired
Diablo without the benefit of wind or gravity assist.
I know from experience this bicycle [2] is much faster with the front
fairing and sock, which I have to believe increases frontal area.
[1] <http://www.varnahandcycles.com/gallery/varna_diablo_01.jpg>.
[2] <http://www.ransbikes.com/Gallery/Archive/images/Sherman1.jpg>.
gdew...@gmail.com
wrote:
> Peter Rathman wrote:
> > ...
> > My car has a coefficient of drag of 0.35, and it has a much more
> > streamlined shape than a regular upright cyclist. Where did your
> > factor of 10 (implying a Cd of 0.1) come from? Figures I've seen for
> > normal cyclists have been more around 0.6 or 0.7....
>
> Here is what a bicycle with a coefficient of drag of slightly less than
> 0.1 looks like:
> <http://www.ent.ohiou.edu/~et181/hpv/Andrea_64.7mph.jpg>. (Yes, she is
> pedaling the bicycle in excess of 64 mph without wind or gravitational
> assistance.)
>
The faster it goes the sharper the wind angle so a fixed sail has a
speed with each angle at which it works best, in a fixed position it
could work as a tail fin, stick a horizontal blade at the top (in a T
shape) and it would make the ride some what more stable I think.
http://www.evworld.com/evworld_audio/michael_lewis.mp3
http://www.evworld.com/article.cfm?storyid=922
peter
> On Thu, 13 Dec 2007 17:56:16 -0800 (PST), peter <prath...@comcast.net>
Tim McNamara
peter
> wrote:
>
> [snip]
>
> >Now does this make any practical sense? No.
>
> [snip]
>
> Dear Peter,
>
> You're getting closer.
No, I'm continuing to say exactly what I did in my original post since
that was correct. Note that in that post I also indicated that the
effect would be too small to be practical and that a passive fairing
makes much more sense if the goal is to reduce the effects of wind
resistance.
>
> You can extract useful energy by sticking a propeller into an
> airstream to use onboard, just as you can extract useful energy
> through a generator's roller to run a light.
>
> You cannot, however, extract energy that is useful for propelling the
> vehicle forward _faster_ because you lose more than you gain.
The obvious difference here, as compared to turning on the generator,
is that no additional drag is created by placing the propeller into a
part of the airstream that would otherwise generate just as much drag
by hitting the cyclist directly. Look at the example I gave in the
previous post where the propeller is a slightly modified fairing shape
and may actually have less air resistance than the cyclist alone. In
that case there's a slight gain even if the energy extracted from the
wind is thrown away - and a slightly larger gain if it's used to aid
the propulsion of the cycle.
But, as I've said all along, I don't think the magnitude of the gain
in practice would be sufficient to justify the added weight,
bulkiness, and complex mechanism. Nevertheless, it is in no way a
perpetual motion machine (of either the first or second kinds) and
there is no physics principle that prohibits obtaining small
mechanical benefits by utilizing part of the wind energy that would
otherwise be wasted upon hitting the cyclist.
Tom Sherman
> "... and it has a fiberglass engine and it runs on water, man!"
What are you talking about?
peter
wrote:
> Peter Rathman wrote:
> > ...
> > My car has a coefficient of drag of 0.35, and it has a much more
> > streamlined shape than a regular upright cyclist. Where did your
> > factor of 10 (implying a Cd of 0.1) come from? Figures I've seen for
> > normal cyclists have been more around 0.6 or 0.7....
>
> Here is what a bicycle with a coefficient of drag of slightly less than
> 0.1 looks like:
> <http://www.ent.ohiou.edu/~et181/hpv/Andrea_64.7mph.jpg>.
Agreed, and clearly for that kind of cycle adding any additional
external apparatus would add considerable extra drag since the shape
has already been optimized for minimum Cd. But the proposal in the
original post included illustrations that made it clear it was for a
regular upright cyclist - not even one in the drops or aero-bar
positions.
unforg...@juno.com
> For example, the object we put out in front of the cyclist could be in
> the shape of an aerodynamic nose cone. Let's say a fairing of that
> type cuts his wind resistance by 20%. Now we add some bearings and
> little fins to the nose cone so it'll start rotating in the wind. The
> fins will obviously add back some air resistance, but by keeping them
> small we can make sure that the overall result is still no worse than
> the unfaired cyclist. Any energy we can extract from the spinning
> cone and use for propulsion is now a net plus if we're only interested
> in power needed to overcome air resistance.
No. Starting with your initial nose cone, the cyclist is putting a
certain amount of power into the system. Once you add the fins, you
start transferring additional momentum from the air into spinning the
fairing. Recall that aerodynamic drag is a vector quantity, not a
scalar. Adding rotational drag to a body will not decrease drag in
the axial direction. In order for this additional rotation to
decrease the total power requirement from the cyclist, more power
needs to be extracted from the rotating fairing than is put into it.
This is simply not possible.
unforg...@juno.com
But where is this magical vortex coming from? Generating a vortex
from an axial flow consumes so much energy that the aeronautics
industry has spent decades developing wing tips specifically not to
create them. There are some very good fundamental reasons why
mainstream aerodynamic vehicle design has been focused on transferring
the minimum possible amount of momentum to the air. If your own study
of fluid dynamics had extended past reading crackpot theories on the
internet, it might be more clear to you.
Androcles
<unforg...@juno.com> wrote in message
news:bc73b6a8-49a9-46ba...@s19g2000prg.googlegroups.com...
: On Dec 13, 10:21 pm, "gdewi...@gmail.com" <gdewi...@gmail.com> wrote:
: > On Dec 14, 2:49 am, "Leo Lichtman" <l.licht...@worldnet.att.net>
: > wrote:
: >
: > > I sat down and designed a propeller that would increase the speed of a
: > > bicycle with NO INCREASE IN POWER INPUT. I wound up with a propeller
that
: > > had no moving parts, and whose blades were shaped like a fairing.
: >
: > Me to.
I sat down and designed a bicycle with no propeller.
I wound up with pedals that increased the speed by
pushing on them.
unforg...@juno.com
wrote:
I believe he's suggesting that our friend Gaby might be developing her
theories with some kind of herbal assistance.
peter
> On Dec 13, 8:56 pm, peter <prath...@comcast.net> wrote:
>
> > For example, the object we put out in front of the cyclist could be in
> > the shape of an aerodynamic nose cone. Let's say a fairing of that
> > type cuts his wind resistance by 20%. Now we add some bearings and
> > little fins to the nose cone so it'll start rotating in the wind. The
> > fins will obviously add back some air resistance, but by keeping them
> > small we can make sure that the overall result is still no worse than
> > the unfaired cyclist. Any energy we can extract from the spinning
> > cone and use for propulsion is now a net plus if we're only interested
> > in power needed to overcome air resistance.
>
> No. Starting with your initial nose cone, the cyclist is putting a
> certain amount of power into the system.
But we're *not* starting with an initial nose cone - we're starting
with a regular upright cyclist. We're then adding a reasonably
aerodynamic windmill right in front of him that consists of a nose
cone shape with fins along the side so it spins when in the wind. The
combination of original rider/bike plus the added windmill can be made
to have the same, or even slightly less, air resistance than the rider/
bike had. Therefore adding the windmill didn't add any extra drag.
But it does allow you to extract some small amount of power from the
wind - power that was wasted before in creating extra turbulence as
the wind hit the decidedly non-aerodynamic rider. Not enough to be at
all practical, but enough to show that in principle some energy can be
extracted.
Note that I had already explicitly said before that the windmill is
not as aerodynamic as the plain unfinned nose cone - but that's not
the comparison since we never actually have the unfinned nose cone.
We start with the plain rider/bike and we add the finned nose cone as
the windmill element.
unforg...@juno.com
You can't suggest a nose cone, and then say it was never there. Sure,
some finned, spinning, nose cone contraption might be more areodynamic
than the cyclist alone, but it's physically impossible for it the
system to be as efficient as the un-finned, non-spinning fairing. So
why make it spin and try to get the energy back out that you put into
it to make it spin in the first place?
datakoll
a reasonably aerodynamic windmill?
that's the point where creative writing enters from, well, use the
lift-stage center.
like magic tricks, right? gues which shell hides the pea? say look
over there at the naked cheerleader.. why there's the pea under shell
one.
distract the reader then write "reasonably aerodynamic windmill cited
by Pieere La Fountainblue, Academy la Marseille Vol 36 Letters
gdew...@gmail.com
> You can't suggest a nose cone, and then say it was never there. Sure,
> some finned, spinning, nose cone contraption might be more areodynamic
> than the cyclist alone, but it's physically impossible for it the
> system to be as efficient as the un-finned, non-spinning fairing.
I can accept a closed body being more efficient as just a propeller.
Still you are arguing about using only the drag. Sailing does not work
like that.
Here you have a picture again. I think you missed it before.
http://i.treehugger.com/images/2007-2-21/Windmill-Sailboat.jpg
The faster you go the more the wind turns into your face so one might
as well put the propeller at the front.
This is why it must spin.
> So
> why make it spin and try to get the energy back out that you put into
> it to make it spin in the first place?
I'm hoping the wind can buy us a sucking vortex.
I've made a new thread for the vortex cone here.
http://groups.google.com/group/rec.bicycles.tech/browse_frm/thread/921e418d6cffd70d
More rotary "excuses".
Enjoy.
:-)
Tom Sherman
With the proper lighting, a spinning nose cone would look really cool at
night.
gdew...@gmail.com
wrote:
You get extra points for this Tom.
lol
CWatters
"Vince Morgan" <vinharAtHereoptusnet.com.au> wrote in message
news:4761c9d0$0$26179$afc3...@news.optusnet.com.au...
>
> "CWatters" <colin....@turnersoak.plus.com> wrote in message
> news:13m2vdu...@corp.supernews.com...
> >
> > "Elmo" <E...@mo.com> wrote in message
> > news:475f8d82$1...@news.peopletelecom.com.au...
> > > Of course what would really happen is that the wind would initially
> blow
> > > you backwards slightly, the backwards motion causing the fan to rotate
> > > backwards which would cause you to go backwards faster, causing the
fan
> > > to rotate faster and so on. The effect would snowball until you were
> > > going backwards at the speed of sound.
> > >
> > > elmo
> >
> > One of these can sail dead into wind....
> >
> > http://i.treehugger.com/images/2007-2-21/Windmill-Sailboat.jpg
> >
> It can? How is that possible?
> Vince
>
Why is it impossible? What physical laws does it break?
A sailing boat can tack upwind. There is little difference. Think about two
sailing boats on opposite tacks towing the same barge. The sail boats go
back and forth but the barge can be towed directly up wind. Look down on a
windmill from above and you see one blade going left to right and the other
right to left.
I believe there was a you tube clip somewhere on the web once.
More examples and some discussion..
http://www.boatdesign.net/forums/showthread.php?t=14182
gdew...@gmail.com
wrote:
> "Vince Morgan" <vinharAtHereoptusnet.com.au> wrote in message
> news:4761c9d0$0$26179$afc3...@news.optusnet.com.au...
Hey hello,
That's a great topic Colin. There is so much to learn here. I bet you
will be crying from laughter when you figure out this negative drag
topic. :-)
I mean, almost everyone else is looking for excuses not to look? And
not looking equals not knowing. No matter how often one self proclaims
being an expert. At best they are experts at finding excuses not to
investigate things.
Down the wind the vehicle has contact with 2 mediums. We should
picture the vehicle as traveling inside the wind using the relatively
moving road as it's propulsion to be able to move down the wind
faster. Or move relative to the medium it sits in.
A poster in the topic above suggest the combination of going faster as
the wind and going directly up the wind. Apparently there are even a
lot of fly-cycles today. I've seen so much propeller driven crafts by
now I'm starting to think it would not require any extra parts to do a
little bit of both. One could both go twice as fast as the wind and
sail straight up the wind using the same rig.
I have a good idea how this guy's special windmill works.
http://www.sailwings.net
Peter Worsley - Wingsailing
http://www.sailwings.net/markone.html
Peter Worsley - Wingsailing Mark 1
http://www.sailwings.net/marktwo.html
Peter Worsley - Wingsailing
http://www.sailwings.net/tldescribed.html
Peter Worsley - Wingsailing
http://www.sailwings.net/wingelec.html
Peter Worsley - Wingsail/Electric
http://www.sailwings.net/article.html
Peter Worsley - Wingsailing
Nice stuff he has.
As a hint all I needed was to know we missed something rather foolish
while deploying the windmill in our imaginations. :-)
But.......
...... if you can sail 45 degrees up the wind faster as you can sail
down it. Then why would we put the windmill straight up the wind! The
thing can stand under an angle and tack the blade up wind half a
rotation then have it capture the full wind over the other half. The
wind is still coming from straight ahead but it's pushing against the
side of the boat now!
This is how the blades stand while sailing up the wind.
http://i.treehugger.com/images/2007-2-21/Windmill-Sailboat.jpg
It's not facing forwards as that would subtract the wind force from
the kinetic energy.
I had already half figured this out with the vortex recumbent cone.
http://gabydewilde.googlepages.com/vortex-recumbent
gabydewilde - vortex recumbent
use side wind rather then drag.
Now lets pretend the drag is side wind. :P
I conclude there are 2 mediums in contact with the vehicle but those 2
have 2 directions each. This gives us 4 directions to work in rather
then just having drag.
^_^
datakoll
Vince Morgan
> > Vince
> >
>
> Why is it impossible? What physical laws does it break?
>
> A sailing boat can tack upwind. There is little difference. Think about
two
> sailing boats on opposite tacks towing the same barge. The sail boats go
> back and forth but the barge can be towed directly up wind. Look down on
a
> windmill from above and you see one blade going left to right and the
other
> right to left.
>
> I believe there was a you tube clip somewhere on the web once.
>
> More examples and some discussion..
> http://www.boatdesign.net/forums/showthread.php?t=14182
>
>
recently.
However, as a thought experiment alone it has problems. Consider the
following.
I'll use a land vehical rather than a boat as an example so as to eliminate
some complexity.
I take a test vehical and mount upon it a wind turbine (as seen in the
video) facing directly into the wind. However, when I get to my test
location, there is no wind. Then I think for a moment. What is the wind
anyway? I soon realize that if I am moving into what is otherwise still air
I have the exact equivalence of wind.
Armed with my new realization I give my test bed a hard push, it finds
itself now apparently in wind, so it accelerates away from me. As it
accelerates there appears to be more wind, so it continues to accelerate.
The wheels I used have very good high speed bearings that offer very little
resistance to motion so the vehical just keeps accelerating until the tips
of the turbine blades hit Mach1?
Vince
datakoll
raise the jibs'l Mr Morgan
II. The relationship between an object's mass m, its acceleration a,
and the applied force F is F = ma. Acceleration and force are vectors
(as indicated by their symbols being displayed in slant bold font); in
this law the direction of the force vector is the same as the
direction of the acceleration vector.
This (preceeding) is the most powerful of Newton's three Laws, because
it allows quantitative calculations of dynamics: how do velocities
change when forces are applied. Notice the fundamental difference
between Newton's 2nd Law and the dynamics of Aristotle: according to
Newton, a force causes only a change in velocity (an acceleration); it
does not maintain the velocity as Aristotle held.
This is sometimes summarized by saying that under Newton, F = ma, but
under Aristotle F = mv, where v is the velocity. Thus, according to
Aristotle there is only a velocity if there is a force, but according
to Newton an object with a certain velocity maintains that velocity
unless a force acts on it to cause an acceleration (that is, a change
in the velocity). As we have noted earlier in conjunction with the
discussion of Galileo, Aristotle's view seems to be more in accord
with common sense, but that is because of a failure to appreciate the
role played by frictional forces. Once account is taken of all forces
acting in a given situation it is the dynamics of Galileo and Newton,
not of Aristotle, that are found to be in accord with the
observations.
III. For every action there is an equal and opposite reaction.
unless a force acts on it to cause an acceleration (that is, a change
in the velocity), as above to the extant of law lll
Otherwise, chaos
The overall theory, an expanding universe will collapse.
Vince Morgan
> There is a difference. In one there is no relative movement between air
and
> land.
>
I was including the wheeled thing going down the road in a video posted
earlier in this thread.
> Sailing boats also experience "apparent wind" and can sail faster than the
> real wind.
>
>
Yes, they do. But I can't see any sail arrangement that would do this if
the vessel is pointed directly into the wind.
However, water or land, the principal is the same actualy. If you view the
wheels as you would the keel. The wheels will resist sideways motion as
does the keel, and will redirect a tangential force either forward or
backward as long as the force is not directly inline with the axles. And it
would be possible to direct the output of the turbine to the wheels via
various means., making it equivalent to the boat I would think
Vince
gdew...@gmail.com
wrote:
> "CWatters" <colin.watt...@turnersoak.plus.com> wrote in message
>
> news:13m8sm7...@corp.supernews.com...
>
> > There is a difference. In one there is no relative movement between air
> and
> > land.
>
> I was including the wheeled thing going down the road in a video posted
> earlier in this thread.
>
> > Sailing boats also experience "apparent wind" and can sail faster than the
> > real wind.
> Yes, they do. But I can't see any sail arrangement that would do this if
> the vessel is pointed directly into the wind.
The sail arrangement is very simple.
We just change the direction of the wind.
ok ok .....
This we cant do so we have to change the direction of the boat !
...ok ok.... then we are not going straight up the wind.
Then....
What if we change the direction the sail is moving in? ^_^
I hear we may look at a sail boat as if it was a blade of a windmill
with earth as it's axle.
Looking at it the other way around the sails(blades) of our propeller
are NOT sailing (moving) directly up the wind at~all. :-)
The blades are sailing _sidewards_ relative to the boat.
The blades tack straight up~wind.
> However, water or land, the principal is the same actually. If you view the
> wheels as you would the keel. The wheels will resist sideways motion as
> does the keel, and will redirect a tangential force either forward or
> backward as long as the force is not directly inline with the axles. And it
> would be possible to direct the output of the turbine to the wheels via
> various means., making it equivalent to the boat I would think
> Vince
http://gabydewilde.googlepages.com/negative-drag
gabydewilde - negative drag
Dan Bloomquist
>> "CWatters" <colin....@turnersoak.plus.com> wrote in message
>> news:13m7q69...@corp.supernews.com...
>> video) facing directly into the wind. However, when I get to my test
>> location, there is no wind. Then I think for a moment. What is the wind
>> anyway? I soon realize that if I am moving into what is otherwise still
> air
>> I have the exact equivalence of wind.
>> Armed with my new realization I give my test bed a hard push, it finds
>> itself now apparently in wind, so it accelerates away from me. As it
>> accelerates there appears to be more wind, so it continues to accelerate.
>> The wheels I used have very good high speed bearings that offer very
> little
>> resistance to motion so the vehical just keeps accelerating until the tips
>> of the turbine blades hit Mach1?
>> Vince
>
> land.
And there isn't between the air and the water? To wit, that doesn't make
sense.
> Sailing boats also experience "apparent wind" and can sail faster than the
> real wind.
Yea, so?
http://en.wikipedia.org/wiki/Close_hauled
I have a hobbie 18, real fun. But if I don't tack quick enough I'll
loose all forward momentum and I'm screwed.
As for Vince's analogy of moving directly into the wind, spot on. I was
going to write such but have a day job.
As for that sail boat, if it is real and not a photo shop job, what a
waste of money. It can not possibly out perform a sail or wing. (And, if
you think it does, show me the paper.) Yet, it would cost a magnitude more.
Another worthless thread with very little critical thinking.....
gdew...@gmail.com
> On Dec 16, 3:17 am, "Vince Morgan" <vinharAtHereoptusnet.com.au>
> wrote:
>
> > "CWatters" <colin.watt...@turnersoak.plus.com> wrote in message
>
> >news:13m8sm7...@corp.supernews.com...
>
> > and
> > > land.
>
> > earlier in this thread.
>
> > > real wind.
gdew...@gmail.com
fascinating,
But I have this feeling as if this suggests Bach and Mozart would
describe the history of music.
I was looking at this just now.
http://youtube.com/watch?v=K5S__p4-AP0
CWatters
"Dan Bloomquist" <publ...@lakeweb.com> wrote in message
news:1719j.458$Sa1...@news02.roc.ny...
> I have a hobbie 18, real fun. But if I don't tack quick enough I'll
> loose all forward momentum and I'm screwed.
>
> As for Vince's analogy of moving directly into the wind, spot on. I was
> going to write such but have a day job.
Vince's analogy is interesting but can be applied to a conventional boat in
the same way. Your Hobbie wouldn't accelerate away if given an initial push
sideways would it.... but it can still sail upwind on a windy day.
Did you realise that on the windmill boat the mill turns a prop under water?
Try towing a barge on a very long rope with your hobbie. If you have someone
in the barge they can steer directly up wind while you tack from side to
side. The center of mass of the _combined system_ is travelling up wind in
the same way that the center of mass of a windmill powered boat does. The
blades on the mill are performing a kind of "rotary tacking". The under
water prop blades provides a force equivalent to the centerboard of a
conventional boat. Each blade on that underwater prop is working (in effect)
exactly in the same way as a centerboard.
> As for that sail boat, if it is real and not a photo shop job, what a
> waste of money. It can not possibly out perform a sail or wing. (And, if
> you think it does, show me the paper.) Yet, it would cost a magnitude
more.
Oh I agree, not the best thing since sliced bread, just an interesting
novelty. I can't vouch for that particular photo but there was a similar one
built in England a few decades ago and there are others photographed and
discused on the links I posted.
I've sailed a variety of boats upto about 40 foot and and I am (or rather
was) a solo rated glider pilot so I do know a bit about this :-)
CWatters
http://www.multihullcentre.co.uk/t36w01.jpg
http://www.multihullcentre.co.uk/t36w02.jpg
even a Hobbie 16 conversion..
http://home.triad.rr.com/boatbarn/jrwindm.htm
Quotes:
"The main advantage of a windmill boat is its ability to "sail" in any
direction, regardless of wind direction."
"Our test boat, a 16' Hobie Cat, achieves a speed of 50% to 60% of the
relative wind, at just about equal speed, in any direction. Speeds up to 10
knots have been achieved so far..."
A grainy video of another example going upwind. Not very convincing but best
I could dig up...
http://www.boatdesign.net/forums/showthread.php?t=1289
References from one of the above::
"Windmill Thrusters: A Comparison of Theory and Experiment",
Journal of Wind Engineering and Industrial Aerodynamics, 20(1985) 267-281
"Optimal Blade Design for Windmill Boats and Vehicles",
Journal of Ship Research, Vol.29, No.2, June 1985, pp. 139-149
"The Physics of a Push-Me Pull-You Boat", Am.J.Phys.,Vol.46,No.10,
Oct.1978, pp.1004-6
Dan Bloomquist
> "Dan Bloomquist" <publ...@lakeweb.com> wrote in message
> news:1719j.458$Sa1...@news02.roc.ny...
>> I have a hobbie 18, real fun. But if I don't tack quick enough I'll
>> loose all forward momentum and I'm screwed.
>>
>> As for Vince's analogy of moving directly into the wind, spot on. I was
>> going to write such but have a day job.
>
> the same way that the center of mass of a windmill powered boat does. The
> blades on the mill are performing a kind of "rotary tacking". The under
> water prop blades provides a force equivalent to the centerboard of a
> conventional boat. Each blade on that underwater prop is working (in effect)
> exactly in the same way as a centerboard.
http://www.physclips.unsw.edu.au/jw/sailing.html
Please use the link to explain "rotary tacking". Or find a paper.
Dan Bloomquist
I seem to have wasted 15 minutes looking for unavailable papers. That is
why usenet drives me nuts. Someone comes along with a claim and says,
'prove it wrong'. Well, science doesn't work that way.
This is real simple. In water you have no traction. The force on the
mill will have to be greater than the force developed by the prop. The
system will not be turbulent free which is what you would need to break
even, sit dead in the water.
CWatters
Ok here is why I called it rotary tacking...
Examine each blade on the windmill in isolation. They do not travel directly
upwind, they travel at an angle to the wind just like a conventional sail.
In effect each blade travels on an infinitely long "tack", one that is
circular or rotary. Hence Rotary tacking.
Consider the forces on one blade as it passes through vertical. In that
position it looks very much the same as a conventional sail and the forces
on it are similar.
What about the keel.... Consider a two bladed windmill with the blades
rotating past the vertical position. The sideways forces balance out so no
need for a keel to resist the sideways force.
CWatters
> This is real simple. In water you have no traction. The force on the
> mill will have to be greater than the force developed by the prop.
You forget something. The windmill extracts energy from the air by slowing
it down. Where does that energy go?
Vince Morgan
[snip]
> What about the keel.... Consider a two bladed windmill with the blades
> rotating past the vertical position. The sideways forces balance out so no
> need for a keel to resist the sideways force.
Actualy, this is only true while the turbine is facing the bow. If the wind
were coming from the side you have 3 forces to consider. 2 are the ones that
ballance out as you mention, and there is drag on the blades and mast that
must be considered too. Being a cat in all cases so far the keel is not
required anyway. On a mono it certainly would. Unless you are managing to
redirect the wind without any drag on the blades, that is a real
consideration.
In answer to where is the energy going, that is up to the user of the mill I
guess. However, if it is powering a proppeller it can only deliver as much
power to that propellor as it is develloping itself, less losses. The drag
that is being produced when you are going into the wind is the force you
need to overcome, and then some. The more power you take from the turbine
the more pitch on the blades, and more pitch means more drag.
Vince
Dan Bloomquist
> "Dan Bloomquist" <publ...@lakeweb.com> wrote in message
> news:LDa9j.469$Sa1...@news02.roc.ny...
>> CWatters wrote:
>>> "Dan Bloomquist" <publ...@lakeweb.com> wrote in message
>>> news:1719j.458$Sa1...@news02.roc.ny...
>>>> I have a hobbie 18, real fun. But if I don't tack quick enough I'll
>>>> loose all forward momentum and I'm screwed.
>>>>
>>>> As for Vince's analogy of moving directly into the wind, spot on. I was
>>>> going to write such but have a day job.
>>> The center of mass of the _combined system_ is travelling up wind in
>>> the same way that the center of mass of a windmill powered boat does.
> The
>>> blades on the mill are performing a kind of "rotary tacking". The under
>>> water prop blades provides a force equivalent to the centerboard of a
>>> conventional boat. Each blade on that underwater prop is working (in
> effect)
>>> exactly in the same way as a centerboard.
>> http://www.physclips.unsw.edu.au/jw/sailing.html
>>
>> Please use the link to explain "rotary tacking". Or find a paper.
>
> Ok here is why I called it rotary tacking...
Bzzzzzzzt!
Did you look at the link?
<snip hand waving>
Dan Bloomquist
I forgot nothing, I wrote, '...force developed by the prop.' But you
seem to be a believer. So, you win....
Vince Morgan
Using a boat rather than a land vehical sets the mood with regard to sails,
but makes the situation more complicated. It must be realized that a
proppeller is not as efficient as a wheel in contact with the ground, even
with transmision losses. You're not making some of the ground move away
from you when you use wheels.
So, using the land vehical makes it very simple I beleive. Put a flexible
drive onto the back of the turbine and feed the power to a wheel or two. If
you can get the vehical to move against the wind you realy have achieved
something. Ratios would be very important, and if you managed to get it
just right, I beleive you will may "almost" achieve equilibrium.
gdew...@gmail.com
> As for that sail boat, if it is real and not a photo shop job, what a
> waste of money
Ahhh, yes. Thank you for putting all the "well if you think it works
then build it" arguments to bed. It's not that you don't have a clue
about the topic but it's now a photoshop. ahhhhhh Well we cant beat
faith systems that stubborn and ignorant.
A rolling windmill is to complicated for you to debunk.
You are never going to succeed.
gdew...@gmail.com
wrote:
> More pictureshttp://www.multihullcentre.co.uk/t36w01.jpghttp://www.multihullcentre.co.uk/t36w02.jpg
>
> even a Hobbie 16 conversion..http://home.triad.rr.com/boatbarn/jrwindm.htm
>
> Quotes:
>
> "The main advantage of a windmill boat is its ability to "sail" in any
> direction, regardless of wind direction."
> "Our test boat, a 16' Hobie Cat, achieves a speed of 50% to 60% of the
> relative wind, at just about equal speed, in any direction. Speeds up to 10
> knots have been achieved so far..."
>
> A grainy video of another example going upwind. Not very convincing but best
>
> References from one of the above::
>
> "Windmill Thrusters: A Comparison of Theory and Experiment",
> Journal of Wind Engineering and Industrial Aerodynamics, 20(1985) 267-281
> "Optimal Blade Design for Windmill Boats and Vehicles",
> Journal of Ship Research, Vol.29, No.2, June 1985, pp. 139-149
>
> "The Physics of a Push-Me Pull-You Boat", Am.J.Phys.,Vol.46,No.10,
> Oct.1978, pp.1004-6
Now lets wait for the complaints again.
Ow here it is already!
On Dec 16, 3:48 pm, Dan Bloomquist <publi...@lakeweb.com> wrote:
> I seem to have wasted 15 minutes looking for unavailable papers.
Well look here!
You cant even convince us there is significant knowledge in the public
domain Dan.
Well, we already know the paper has references. The rest you can use
your imagination.
Even the abstract says it can move up the wind.
But after reading the abstract you say:
> This is real simple. In water you have no traction. The force on the
> mill will have to be greater than the force developed by the prop. The
> system will not be turbulent free which is what you would need to break
> even, sit dead in the water.
Could you stop talking bullshit?
gdew...@gmail.com
wrote:
> Oh I agree, not the best thing since sliced bread, just an interesting
> novelty.
That's nonsense.
This boat can sail where only motor boats can go, it's easy to
operate, it should also have a very comfortable living environment
with so much electricity to use and there is not much noise from
engines but most of all one can just remain in one place until the
food runs out.
This kind of boat you can live on.
Tommy
wrote:
> "Elmo" <E...@mo.com> wrote in message
>
> news:475f8d82$1...@news.peopletelecom.com.au...
> > Of course what would really happen is that the wind would initially blow
>
> > you backwards slightly, the backwards motion causing the fan to rotate
> > backwards which would cause you to go backwards faster, causing the fan
> > to rotate faster and so on. The effect would snowball until you were
> > going backwards at the speed of sound.
>
> > elmo
>
> One of these can sail dead into wind....
>
> http://i.treehugger.com/images/2007-2-21/Windmill-Sailboat.jpg
no it cant