Upwind Sailing Fantasy
Capt. Neal®
The following is a copy of an email I found on a floppy.
This was posted several months ago the first time the
discussion of sailing directly into the eye of the wind was
was brought up by some idiot (Pete 32) who claimed his
windmill contraption could sail straight upwind. Since many
of you are new to the group, I thought I would post it again
as it debunks, in simple language, the fantasy of sailing
straight upwind with a windmill-type contraption.
I wrote:
Dear Group,
Sailing directly upwind in a contraption such as exhibited
by Pete32 is a fantasy. I have tried over and over again in
the most simple ways possible to convince some of you
hydrochepalic imbeciles of that fact but I may as well be
talking to lead ballast or a blonde. How can there be so
many brains and so miserably few of the lot functioning?
Throw up web site with a few lame sketches, a fake postage
stamp-sized movie of a model powered by batteries, and some
other gobbledygook along with unbelievable excuses about
trees blocking the wind, slipping and forgotten belts, etc.
and people believe. These are the same people who flock to
various religious artifacts, icons that allegedly weep tears
or drip blood, looking for some miracle. It is no wonder
that snake oil salesmen prosper. The only true miracle would
be if these same people suddenly became sane people.
Having to deal with such rabble in this group is fast
becoming an onerous task but, being a man of stout
constitution with an abiding concern for truth, justice and
the American way, I shall never cease to persevere against
them. (Thank you, Sir Winston!)
Pete32 would have you believe that a wing creates up to
fifty times more lift than it causes drag. He claims to use
this abundant lift to overcome the drag of the wing and the
drag of the vessel's superstructure, etc. It sounds
plausible to most of you clowns, doesn't it? Admit it,
doesn't it?
If you said, 'Yes!', then you are gullible. Stupid and
gullible. Pathetic, stupid and gullible. Why? Because you,
like Pete32, are putting the cart before the horse.
Let's take a nice streamlined Lear jet. It has long slender
wings capable of providing enough lift to suspend tons of
airplane in the air. The wings and the aircraft produce drag
but the lift is obviously greater or it would not fly. Let's
say Pete32 is correct and this aircraft produces fifty times
more lift than it has drag. Let us also say that the
aircraft weighs two tons. It follows that the wings produce
at least two tons of lift. That converts to 4000 pounds of
lift. Are you following me so far?
Let us now compute the drag. Four thousand pounds of lift
divided by fifty equals eighty pounds of drag.
Now, here is where the 'cart before the horse' comes into
play. The Lear jet is just sitting on the runway. The Lear
has eighty pounds of drag and ZERO pounds of lift. A
little wind blowing across the wings does not produce
measurable lift. Now, fire up about 2000 horsepower's worth
of turbines which are spun up by utilizing the energy
released by the burning of kerosene and direct the thrust
towards the rear. The drag is quickly overcome, even though
it increases with the increasing speed, and the aircraft
moves off smartly down the runway. Eventually enough forward
speed is gained so sufficient lift is generated to raise the
aircraft off the ground. If the engines should happen to run
out of kerosene and stall, the Lear jet would quickly loose
altitude and touch down again on the runway. In this
instance, a wee bit of drag quickly overcame fifty times
more lift. How is this possible??? According to Pete32's
fantasies, the Lear should just keep going as the drag is
insignificant compared to the lift.
Pete32 is guilty of putting the cart before the horse. One
cannot overcome drag with lift as lift does not exist until
drag is overcome. You cannot overcome drag only with the
very same device that causes the drag in the first place.
You cannot create energy out of nothing. You must have a
powerful external source. In his spinning air propeller,
there is indeed lift but the lift is doing no useful work
and is only causing the propeller to spin. The wind blowing
across it is providing enough external energy to create
enough lift to overcome the small initial amount of drag,
but the drag quickly increases until the propeller's rpms
stabilize. At this point lift and drag are equal. If this
were not the case, the propeller would continue to turn
faster and faster until it self-destructed. So you do NOT
have fifty times more lift than drag. You have EQUAL lift
and drag at constant rpm.
Let's put the contraption in gear! What happens? Suddenly
drag increases drastically! Pulleys are spinning, belts are
turning, rubbing and heating up, bearings are loosing energy
to friction; a water propeller starts to turn resulting in
even more friction loss. In short, somebody just stepped on
the brake. There is now MORE drag than lift. This brake will
rob the system of energy faster than the wind can input
energy. The air propeller will slow down. Lift will
decrease. Drag will remain the greater force and the air
propeller will slow down even more. Pretty soon it will
simply grind to a halt.
Like I have been saying all along, you cannot create energy
out of nothing. Lift may well be POTENTIALLY fifty times
more than drag but drag is persistent, pervasive and
increases to become equal to lift at some point and it
always wins by virtue of the fact that it exists all the
time whereas lift must be created by overcoming the drag.
Lift cannot overcome drag without external sources of power.
Head on wind cannot be considered a viable external source
of power because it causes drag which acts directly against
itself. Drag fights back until it is just as powerful as the
lift or the propeller would just continue to spin faster and
faster and faster as stated above.
Is this explantation finally clear enough for you synapsely
challenged simpletons to grasp??? You should all be ashamed
of yourselves and bow down and pay homage to the Captain for
looking after your interests. Why, if it wasn't for me, the
next thing you know, you will all be buying SAIL LOCO's junk
to install on your brand new MAC26Xs. PUTZES!
Respectfully,
Capt. Neal
~~~~~~~~~~~~~
James H. E. Maugham
138 lines of absolutely NOTHING! Whoops, my fault. New newsreader and I
haven't set the filters properly.
"Plonk"
There, that's MUCH better.
James
Bill Bannon
produce a windmill that will propel the boat faster than the wind
holding it back, you would increase the apparent wind against the
windmill, causing it to catch more wind, and thus go faster. This
effect would continue until the boat's hull integrity was exceeded, or,
if its trilithium powered external shield array is working properly,
until the vessel reaches warp 9.99999999 repeating, which all good
trekkers know is the fastest you can go.
SR Bill Bannon
Starfleet Academy
New London, MN (not CT, unfortunately)
The only thing I can't tolerate is intolerance.
Roger Wollin
<Capt...@Bigfoot.com> kerfuffled thusly:
>Dear Group,
>
>The following is a copy of an email I found on a floppy.
>This was posted several months ago the first time the
>discussion of sailing directly into the eye of the wind was
>was brought up by some idiot (Pete 32) who claimed his
>windmill contraption could sail straight upwind. Since many
>of you are new to the group, I thought I would post it again
>as it debunks, in simple language, the fantasy of sailing
>straight upwind with a windmill-type contraption.
Garbage snipped
That's right, I remember that letter. I fell about laughing the first
time I read it too.
Regards
Roger
Mark Weaver
Yes, I remember your 'proof by lack of imagination'. Somebody pointed out
that, if you can make progress into the wind by tacking back and forth, it is
clearly possible in principle to build a vessel that does so by doing
'micro-tacking' within the vessel itself, but that wasn't simple enough for
you. So, how about this for a proof-in-principle of a vessel that goes
straight into the wind.
1. Drop anchor
2. Charge batteries with wind generator
3. Raises anchor
4. Use electric motor to power into wind until battery dies.
5. Goto #1
If the use of an anchor seems like cheating to you, then substitute a large
sea anchor instead. Note that this is not a perpetual motion machine because
it relies on the fact that the air is moving relative to the water -- it won't
work in a dead calm (even if try to get it started by giving it a push).
Do I expect this explanation, in simple language, to convince you? Of course
not, but there may be hope for others...
Mark
Capt. Neal®
1) the use of an anchor of any type for that is adding
energy to the system invalidates my claim that you cannot
use a force alone to move an object directly against that
force.
2) the storage of energy in a battery is even more blatant a
cheat and invalidates your entire argument if you have to
rely on it.
That idiot Pete32 still claims he can sail his contraption
directly into the eye of the wind using no stored energy. I
believe he claims to run a water propeller from an electric
motor which is energized by a generator run by the windmill.
Nonsense! If this were possible (and I wrote a sarcastic
post about it), one could use the same rig mounted on an
engineless automobile, head the automobile into the wind so
the windmill would spin, engage the electric motor and off
you would go. Since the faster you went, the more apparent
wind you would have, the faster the windmill would spin and
the more electricity it would generate, the faster your
forward speed would be until you were soon independent of
the actual wind and in danger of being ticketed for speeding
(provided the officers could catch you).
The big petroleum companies are quaking in their boots
hoping Pete32 never adapts his sailing contraption to land
use as they would soon be put out of business. Ha ha aha
haha hhaha ah ahhah a h hahahahahha! Lord, you people are
so stupid and gullible.
Don't you see how ludicrous such a perpetual motion machine
is? Why are you willing to believe it will work on water.
Respectfully,
Capt. Neal
~~~~~~~~~~~~~
Mark Weaver wrote in message ...
JAXAshby
>I object to at least two points.
>
>1) the use of an anchor of any type for that is adding
>energy ........
WHAAAAAAATTTT?????!!!!!!!!!!!!!!!!!
How much gasoline (or diesel fuel, as the case may be) to hold an anchor to the
bottom???
Roger Wollin
<Advo...@midstate.tds.net> kerfuffled thusly:
Oh dear Bill, you've fallen into the same traps of illogic as the
Crapton always does.
1) Just because because you've thought of a way to make it work better
than claimed, it doesn't mean that it cannot work at all.
2) If you could convert the energy of the wind 100% into propulsion,
and you were on a frictionless surface and there was no air drag you
have described exactly what would happen, but what happens in real
life is, an increase in apparent wind speed *will* produce an increase
in propulsive power, but it also increases the aerodynamic drag, and
under The Immutable Law of Sod we all know which eventually wins.
3) Your reasoning can also be used to demonstrate that a sail boat
cannot go to windward at all. As the boat speed increases the apparent
wind also increases, which increases the power generated by the sail,
which increases the speed, which increases the apparent wind...
Regards
Roger
Capt. Neal®
As foolish as you looked in that female underwear, you sound
even more foolish when you wrote:
JAXAshby wrote in message
<19990916175238...@ng-fk1.aol.com>...
------------------------------
Use your head for something other than perusing women's
underwear catalogs, sweetheart. When anchored or tied to a
dock whatever force is on the lines that hold the vessel in
place is a force being added to the system.
You know, like when you strap the garters to your hose,
there is a certain amount of force required to hold up the
hose and this causes the garters to stretch. If you cannot
figure it out, I'm sure Loree could tell you all about it.
Respectfully,
Capt. Neal
~~~~~~~~~~~~~
JAXAshby
>JAXAshby wrote in message
><19990916175238...@ng-fk1.aol.com>...
>>cappy states:
>>
>>>I object to at least two points.
>>>
>>>1) the use of an anchor of any type for that is adding
>>>energy ........
>>
>>
>>WHAAAAAAATTTT?????!!!!!!!!!!!!!!!!!
>>
>>How much gasoline (or diesel fuel, as the case may be) to
>hold an anchor to the
>>bottom???
>------------------------------
>
>..... When anchored or tied to a
>dock whatever force is on the lines that hold the vessel in
>place is a force being added to the system.
>
>
will someone who was listening in JrHS science class explain it to the genius?
Mike Pupeza VE3EQP
Picture this, Oh Wise One!
And I DEFY you to rebut it's possibillity!
I have a 4 wheel vehicle, with latches on the wheels to prevent the wind
from blowing it backward (Anchor - sideways keel - whatever).
Then, my big propellor, which is spinning with the wind, is spinning up my
big centifugal storage device, a 'flywheel', which then obtains awsome
stored energy! WOW!
I then engage this 'Flywheel', to drive some gearing to the wheels, and,
simultaneously, release the brakes!
Capt. Neal - this 'device' will MOVE FORWARD into the wind!!!!!!! Trust me,
or PHYSICS!
As it slows, I then apply the 'brakes, wait, store up some more energy, then
move forward again!
It is NOT 'Perpetual Motion', because the efficiencies are fall lower than
100%. AND a LOT of energies are being used, in 'Time Dependant' modes, as
needed.
It IS POSSIBLE, and so are 'SOME' types of 'Sailing' vessels. This is NOT
Rocket Science, but YOU should see that there is more than one way to 'skin
a cat'! (Not yours, he looks like a nice one!)
Don't come on strong about anchors, sea anchors, underwater parachutes,
blockers, etc., to slow down drift, etc., because that is EXACTLY what
allows a Sailboat to move to windward. We only have to be MORE AGRESSIVE
than a Keel, in the way it's done to move a boat - STRAIGHT INTO THE WIND!!
This just came to me, while sailing off the wind, using the SAME big
propellor, and Flywheel, store up energy until the wheel is humming, point
into the wind while engaging the prop, and POINT INTO THE WIND, until energy
drops off, Then back off he wind and recharge the Flywheel.
IT CAN ALL BE DONE, but not yet practically!
How about 'Venetian Blind, type keels, that pulse open when driving forward,
but close while charging the Flywheel!
Hey Cappy, you can use my analogy, get a patent, develop it, and reap the
Royalties.
I release you from any responsibilities to ensure that I get any of those
Monies - however, with your 6 Mil, you don't need it, so I would like some
back. You know, Tuck Store cash (For those of you who went to Camp as
kids!).
Cappy, open your mind! These things ARE POSSIBLE!
Capt, Crew, and Bottle washer - Mikey!
Capt. Neal® <Capt...@Bigfoot.com> wrote in message
news:QodE3.4761$d71.1...@news4.giganews.com...
> I object to at least two points.
>
> 1) the use of an anchor of any type for that is adding
Bill Bannon
contraption that used the wind directly for propulsion. If we are going to use
it for building up and storing energy, or use solar cells as someone else
suggested, why not use gasoline. With a bit of that and triple 200 HP Johnsons
on the tail end of a Mastercraft, I could "sail" into the wind pulling a four
level pyramid. And I wouldn't even need a mast or mainsail.
Becoming a bit more serious about it, though, don't you think tacking would get
you to your destination more quickly than starting and stopping while your
flywheel was charged by the wind?
Bill Bannon
New London, MN
Marcus G Bell
> Sorry, I thought we were talking about "sailing," or atleast
> some type of contraption that used the wind directly for
> propulsion. If we are going to use it for building up and
> storing energy, or use solar cells as someone else suggested,
> why not use gasoline. With a bit of that and triple 200 HP
> Johnsons on the tail end of a Mastercraft, I could "sail" into
> the wind pulling a four level pyramid. And I wouldn't even need
> a mast or mainsail.
If the wind could be used to "create" gasoline from water and
carbon dioxide recycled from the exhaust of your johnson, then I
don't see why this should be strictly disallowed, provided it was
happening in more or less real time. Solar cells are a cheat,
unless illuminated by lights powered by a wind generator.
But you are correct, storage of energy via springs,
petrochemistry, redox potential, rotational inertia, and so on
seems to violate the spirit of the venture.
> Becoming a bit more serious about it, though, don't you think
> tacking would get you to your destination more quickly than
> starting and stopping while your flywheel was charged by the
> wind?
I rather do think so, yes.
Though it is an interesting idea nonetheless, I think the flywheel
is not necessary if the windmill drives a waterscrew directly. So
the pauses at anchor while the flywheel charges could be
eliminated. The flywheel could allow fast bursts between the
pauses, whereas without the energy storage it would be slower but
more steady progress. Tortoise and hare.
As to whether a windmill/propeller boat would have a better VMG
than would a sailboat, it depends a lot on the efficiency of both
boats in question.
-- -- Marcus. ( be...@mail.med.upenn.edu )
Cin...@home.com
more. Are you intentionally coming across as a blithering idiot?
"Capt. NealŽ" wrote:
>
> JAX,
>
> As foolish as you looked in that female underwear, you sound
> even more foolish when you wrote:
>
> JAXAshby wrote in message
> <19990916175238...@ng-fk1.aol.com>...
> >cappy states:
> >
> >>I object to at least two points.
> >>
> >>1) the use of an anchor of any type for that is adding
> >>energy ........
> >
> >
> >WHAAAAAAATTTT?????!!!!!!!!!!!!!!!!!
> >
> >How much gasoline (or diesel fuel, as the case may be) to
> hold an anchor to the
> >bottom???
> ------------------------------
>
> Use your head for something other than perusing women's
> underwear catalogs, sweetheart. When anchored or tied to a
> dock whatever force is on the lines that hold the vessel in
> place is a force being added to the system.
>
Bob Walters
You sir, are what we call a nit-wit savant. Yes, you can type, but you
certainly don't know much about what makes a sailboat operate. Your so
called proof sounds even more stupid this time than the last time you
offered it up for our ridicule.
It re-confirms that you are completely confused about basic physics.
The point you continue to miss is that sailboats operate in two fluids
(namely water and air) with very different properties . Sailboats "work"
because of the difference in density and speed between the two.
For you, that means you can sail when the wind is blowing OR the water is
moving. (Remember how silly you sounded some weeks back when you argued
about sailing in a dead calm on a moving river?)
Please notice that neither submarines or aircraft are normally equipped with
sails and keels. It's only SAILBOATS that have such devices. This fact
should be a clue.
Your lack of understanding of sailing is exceeded only by your lack of
understanding about how airplanes fly. Thank God you don't claim to have a
pilots license.
In the future please limit your scientific tirades to the wonderful workings
of your cedar bucket.
Bob Walters
Peter Moore
Capt. NealŽ wrote in message ...
>Dear Group,
>
>The following is a copy of an email I found on a floppy.
>This was posted several months ago the first time the
>discussion of sailing directly into the eye of the wind was
>was brought up by some idiot (Pete 32) who claimed his
>windmill contraption could sail straight upwind. Since many
>of you are new to the group, I thought I would post it again
>as it debunks, in simple language, the fantasy of sailing
>straight upwind with a windmill-type contraption.
>
>I wrote:
Despite my earlier doubts about this wind turbine contraption I concede that
it does *work* but only in controlled conditions. These conditions are in
dead flat water with constant wind direction, and of course all we true,
blue water sailors (and Neal) would say this surely is not practical.
From my extensive experience in flying tail dragging airplanes, I have
experienced at first hand the gyroscopic effect known as precession. In the
airplane just before takeoff the pilot "picks' the tail up and at the same
time applies a bootfull of left rudder to compensate for the gyroscopic
precession caused by the propellor as the tail is lifted.
The same effect would happen with this ridiculous wind turbine thing, every
time the nose of the boat dropped into a wave trough, the wind turbine would
precess to one side, when the nose of the boat rose on a wave crest the wind
turbine would precess to the other side. The total effect of the bows rising
and dropping would be an uncontrollable oscillation side to side and before
long the whole apparutus would self destruct.
Back to the drawing board boys....oops sorry Loree, shouldnt you be
concerning yourself these days with the more important feminine things such
as the color of nail polish or lipstick? and leave the importance of physics
to us mere males?
Saludos
Peter
Capt. Neal®
made more sense to you.
Respectfully,
Capt. Neal
~~~~~~~~~~~~~
Cin...@home.com wrote in message
<37E1C515...@home.com>...
Capt. Neal®
but storage devices are not allowed. We are talking about a
direct harvesting, redirecting, and use of the energy of the
wind to push an object directly against the flow of this
energy. Pete32 is trying to use available energy directly
against itself and come up with a net gain. This is
impossible according to accepted laws of physics.
Respectfully,
Capt. Neal
~~~~~~~~~~~~~~
Mike Pupeza VE3EQP wrote in message ...
>> I object to at least two points.
>>
>> 1) the use of an anchor of any type for that is adding
Ed Chell
If ever a contraption is available to move me directly into the wind at a respectable pace whenever in whatever conditions exist at
the time, I may look into it.
I am sure however that this day will never come.
I will continue to use _my_time to get the most from more conventional methods of wind power.
A much more enjoyable pastime than wading thru the constant drivel of mini wars waged here.
Phil, looks like a great day coming tomorrow. Hope your paint is dry.
--
Saludos,
Ed Chell
Capt. Neal® <Capt...@Bigfoot.com> wrote in message news:oGpE3.6502$wr5.1...@news6.giganews.com...
Capt. Neal®
ice is but frozen water.
An automobile works the interface between two mediums
(provided you put a sail on it).
Why not put Pete32's rig on a special lightweight automobile
that is powered by an electric motor? If Pete's fantasy is
real and works for a sailboat it would work for an
automobile. So, then the auto could be pointed into the
wind, proceed to move forward at a faster and faster pace
until the real wind was insignificant with respect to the
apparent wind and soon the auto would be cruising the
freeways in need of some way to slow it down because, as the
apparent wind increased, so would the power, as the power
increased so would the apparent wind, etc. etc. etc. ad
nauseum.
It can't be done or it would have been done already.
Believe it!
Respectfully,
Capt. Neal
~~~~~~~~~~~~~
Bob Walters wrote in message
<7rt6od$t0b$1...@bgtnsc02.worldnet.att.net>...
Bob Walters
Let's take the example you mention......an ice boat.
It is common knowledge that high performance ice boats can travel several
times the speed of the true wind. By the way, lately some high performance
land vehicles have been setting new speed records, also at many times the
speed of the true wind.
This is NOT black magic. It is NOT perpetual motion.
In fact, they do this by just the mechanism you mention. As they
accelerate, the apparent wind increases. They accelerate further, and the
apparent wind increases further. Before long, the apparent wind speed is
several times the speed of the true wind.
The ice boat does not simply keep going faster and faster "etc. etc. etc. ad
nauseum". This fact does NOT mean that ice boats are impossible.
There is an upper speed limit which is dependent primarily upon the sum of
the aerodynamic drag and friction drag relative to the efficiency of the
sail rig.
These vehicles, like sailboats, are simply extracting energy from the air,
(by re-directing the flow) and by virtue of their very low drag, are able to
attain surprisingly high speeds. Sailboats are handicapped by their higher
drag, so don't generally go as fast as ice boats, but the idea is the same.
There is a natural speed limit to all these devices. Observing (or just
figuring out in your mind) that an ice boat has a top speed limit does not
mean that ice boats are somehow impossible.
A greatly more complicated system for extracting energy from the moving wind
(like a windmill and prop) would suffer (it seems obvious to me) greater
losses than that of an ordinary sailing rig, plus it's expensive, and
somewhat dangerous; however, just because you don't see lots of these
vehicles buzzing around does NOT mean that it's impossible to do such a
thing.
It seems to me that anyone who's had a bit of education would not imagine
that a windmill/prop or windmill/driven-wheel vehicle would just keep going
faster and faster directly into the wind.
Realizing that going faster and faster "etc. etc. etc. ad nauseum" is
impossible, does NOT automatically mean that simply going must also be
impossible.
It seem likely that such a device would quickly reach a state of
equilibrium, and I suppose most would guess that top speed would be rather
low.
But at the end of the day, the idea of using a windmill to extract energy
from wind and then convert this energy to propulsive thrust in a different
medium is not automatically impossible just on it's face value, as you seem
to claim.
Bob Walters
Marcus G Bell
> Why not put Pete32's rig on a special lightweight automobile
> that is powered by an electric motor? If Pete's fantasy is real
> and works for a sailboat it would work for an automobile. So,
> then the auto could be pointed into the wind, proceed to move
> forward at a faster and faster pace until the real wind was
> insignificant with respect to the apparent wind and soon the
> auto would be cruising the freeways in need of some way to slow
> it down because, as the apparent wind increased, so would the
> power, as the power increased so would the apparent wind, etc.
> etc. etc. ad nauseum.
This has been explained at least twice.
The vehicle would not continue to accellerate ad infinitum because
as the speed of the vehicle increases over the road, wind drag on
the auto body increases more rapidly than does the power available
from the apparent wind. Therefore, a steady-state speed is reached
where all forces and energy fluxes are in balance, and this is a
finite speed.
James H. E. Maugham
>
> From my extensive experience in flying tail dragging airplanes, I have
> experienced at first hand the gyroscopic effect known as precession. In the
> airplane just before takeoff the pilot "picks' the tail up and at the same
> time applies a bootfull of left rudder to compensate for the gyroscopic
> precession caused by the propellor as the tail is lifted.
> The same effect would happen with this ridiculous wind turbine thing, every
> time the nose of the boat dropped into a wave trough, the wind turbine would
> precess to one side, when the nose of the boat rose on a wave crest the wind
> turbine would precess to the other side. The total effect of the bows rising
> and dropping would be an uncontrollable oscillation side to side and before
> long the whole apparutus would self destruct.
I don't think anyone is suggesting that a windmill powered vessel is
going to head for the open seas in the near future. They're a toy and
they're best kept for use in and on protected waters, but that doesn't
change the fact that they do exist and they do sail directly into the
eye of the wind, all without benefit of hidden power sources such as
batteries, inertialess flywheels, etc.
You'd have to be significantly pitching and rolling for precession to
become an issue, but you're correct that it could become a problem for a
vessel on the open seas. Perhaps that would be the time to switch to
your upset cycloidal windmill?
Same for the arguments about torque from the rotor, it's a non-issue as
the power source is external.
Regards,
James
Cin...@home.com
make some out of hand sexual remark about men in their underwear or
naked men? Apparently you have thoroughly studied and enjoyed the "pix
of JAX in his underwear" and presumably other men as well. De gustibus
non dubitantes est. (Taste ought not to be disputed.) Hey Monkey Boy
whatever gets you through the night.
Now since you have wayyyyyyyyy too much time on your hands, why not pick
up a copy of Chapmans or some other basic book on sailing. And yes get
off the boat every now and again. In the meantime, let me introduce you
to my kill file.
"Capt. NealŽ" wrote:
>
> Had you seen the pic of JAX in his underwear, it would have
> made more sense to you.
>
> Respectfully,
> Capt. Neal
> ~~~~~~~~~~~~~
>
> Cin...@home.com wrote in message
> <37E1C515...@home.com>...
> >You have convinced me that the only way you could say less
> is to write
> >more. Are you intentionally coming across as a blithering
> idiot?
> >
> >"Capt. NealŽ" wrote:
> >>
> >> JAX,
> >>
> >> As foolish as you looked in that female underwear, you
> sound
> >> even more foolish when you wrote:
> >>
> >> JAXAshby wrote in message
> >> <19990916175238...@ng-fk1.aol.com>...
> >> >cappy states:
> >> >
> >> >>I object to at least two points.
> >> >>
> >> >>1) the use of an anchor of any type for that is adding
Loree Thomas
>
> Back to the drawing board boys....oops sorry Loree, shouldnt you be
> concerning yourself these days with the more important feminine things such
> as the color of nail polish or lipstick? and leave the importance of physics
> to us mere males?
It's ok Peter... men just can't seem to help themselves, so I forgive
you you ignorance/arrogance.
I let my boy friend pick the color of my nails and lips... much the same
way I let him pick the color (not the make/model) of our car. He choose
red in all three cases.
About the precession problem.... seems there are a couple of things you
could do... counter rotating flywheel being the first one that springs
to mind... but I never claimed to be any kind of engineer and that is an
engineering problem. I wouldn't have gotten involved in the thread at
all except it was about whether it was possible theoretically.
I certainly never claimed it was practical at any point!
Hugs,
Loree
Thomas Stewart
setting and waying anchor?
JAXAshby
>From my extensive experience in flying tail dragging airplanes, I have
>experienced at first hand the gyroscopic effect known as precession. In the
>airplane just before takeoff the pilot "picks' the tail up and at the same
>time applies a bootfull of left rudder to compensate for the gyroscopic
>precession caused by the propellor as the tail is lifted.
Very little of that is precession. Some comes from the asymetrical thrust of
the advancing blade of your propellor having a higher angle of attack than the
retreating blade because your propellor is canted back while the tail wheel is
on the ground (this is a genuine problem in very high performance, propellor
driven airplanes with small rudders, i.e. a P-51). Most comes from the
asymetrical prop wash hitting one side of your rudder/stablizer more than the
other.
There was a WW One fighter plane with a serious precession problem (so bad, in
fact, the plane generally could turn only in one direction), but that was
because the engine crankshaft was fixed to the aircraft while the (very heavy)
engine rotated with the prop.
Capt. Neal®
Cin...@home.com wrote in message
<37E26883...@home.com>...
>Now listen up Monkey Boy <snipped> In the meantime, let me
introduce you
>to my kill file.
------
"Plonk!" Ah, the sweet sound of success. Now, if only I
could get rid of Bobsprit so easily!
Respectfully,
Capt. Neal
~~~~~~~~~~~~~
Capt. Neal®
be wrong because the auto will never start going on its own
any more than Pete's fantasy boat will start going directly
into the wind on its own.
Hey, I just had an idea where I can easily win the cross
country solar powered automobile race. I will mount one
teensy weensy speck of a solar cell on the hood of the car
and wire it to an electric engine so it will qualify as a
solar powered auto. Then I will sneak over to England and
steal Pete32's windmill contraption and mount it on the car
as well and rig it so it will also power the electric motor.
Rain or shine, day or night, my little solar car will cruise
all the way across America and I will be the hero of the
day. There will simply be no stopping me as once the
windmill/solar auto reaches about, say 30 mph, and reaches
this equilibrium you talk about, it will just go and go and
go and even put the Everready Bunny to shame.
Hey, Keywestwym, how 'bout another hit off that bong!
HHssssssssssssssss! . . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . .. . . . . . . . . . . .
.. AAhhhhhhhhhhhhh!
Let's see what else I can 'invent.' Apparently there are
plent of fools out there who are willing to believe
ANYTHING.
Respectfully,
Capt. Neal
~~~~~~~~~~~~~
Marcus G Bell wrote in message
<7rtesj$25$2...@netnews.upenn.edu>...
Capt. Neal®
address the issue of sailing directly into the eye of the
wind. Ice boats, for all their remarkable efficiency, cannot
sail directly into the eye of the wind any more than
Pete32's fantasy boat can. We need to stick to the main
point here, otherwise we stand in danger of sounding like a
gaggle of women.
Respectfully,
Capt. Neal
~~~~~~~~~~~~~
Bob Walters wrote in message
<7rtefm$cro$1...@bgtnsc03.worldnet.att.net>...
Roger Wollin
kerfuffled thusly:
>Dear fellow sailors and Neal,
>Despite my earlier doubts about this wind turbine contraption I concede that
>it does *work* but only in controlled conditions. These conditions are in
>dead flat water with constant wind direction, and of course all we true,
>blue water sailors (and Neal) would say this surely is not practical.
Well done Peter, you are beginning to see the light.
If you look at the posts in this discussion you will find that most,
if not all, of those supporting Pete Worsley & Co make no claim that a
wind turbine type vessel will offer world beating performance, or even
be practical. I think I was the person who fired these threads up
again, not to *prove* that such a craft would work (I am agnostic on
this aspect myself, though I am becoming more certain that they do),
but to discredit those windbags such as Crapton who claim that they
are *totally impossible*as a knee jerk reaction, based on their
knowledge that sailboats cannot travel head to wind, and on some vague
memory that energy is conserved, or entropy always increases.
Regards
Roger
Roger Wollin
<Capt...@Bigfoot.com> kerfuffled thusly:
>That idiot Pete32 still claims he can sail his contraption
>directly into the eye of the wind using no stored energy. I
>believe he claims to run a water propeller from an electric
>motor which is energized by a generator run by the windmill.
>Nonsense! If this were possible (and I wrote a sarcastic
>post about it), one could use the same rig mounted on an
>engineless automobile, head the automobile into the wind so
>the windmill would spin, engage the electric motor and off
>you would go. Since the faster you went, the more apparent
>wind you would have, the faster the windmill would spin and
>the more electricity it would generate, the faster your
>forward speed would be until you were soon independent of
>the actual wind and in danger of being ticketed for speeding
>(provided the officers could catch you).
Crapton
Your stupidity never fails to astound me. If you think that
sarcastically exaggerating the claims for a device acts as proof that
it cannot work, then your brain must be residing in the bottom of your
cedar bucket with the rest of the shit.
If you want a more polite rebuttal to your nonsense see my reply to
Bill Bannon earlier in this thread.
Disrespectfully
Roger
Thomas Stewart
Which direction to the wind is a ice boat sailing? It seems anyone with
any eduction that would use it for an example
would know. Are they sailing upwind or downwind?
HOW'S THAT, JAX, for making a statement a question as you suggested. You
can answer and explain how it applies to a wind prop, please?
Thom
Bob Walters
can sailboats or sail cars (or whatever you call wheeled vehicles). And
while they can't sail directly into the wind, they are able to easily travel
faster than the wind, something that a simple mind may have trouble
understanding.
You see, they extract wind energy by simply re-directing the air flow (when
sailing on a beat or reach. Downwind sailing is a different matter, and of
no relevance to this discussion.)
As the sail captures and bends the wind, there is a component that tries to
make the boat slip sideways. This is opposed by the keel, runner, wheel, or
what-have-you operating (and this is important) in a medium other than the
moving air (wind).
The other important (and generally smaller) component is what you might call
"thrust", and it is this component which drives the vehicle forward.
The geometry of the situation limits most vehicles to something like 45
degrees to the true wind, or slightly less in high performance versions of
boats, ice boats, etc. However, none of them can operate directly into the
wind. Any good book on sailing theory discusses this point in some detail.
Picture a boat on a beat, turning into the eye of the wind, and attempting
to sail upwind. Think about what the sheeting angle would be in such a
situation. You'd have to have the main hauled up to "windward" plus about
15 or 20 degrees in an attempt to deflect the wind, and thereby extract
useful energy to drive the boat.
However, sketching a quick force diagram would show that when the wind is
re-directed in this situation, there is no component of the force diagram
(thrust) acting in the direction of travel and you would slow down even
faster than if you left the main strapped in amidships.
All this is because these vehicles use sails to extract wind energy. If you
understand how sails work, you can understand why they won't work directly
upwind. My point is to try to get you to understand that the limitation
about direct upwind sailing is, for most of us, a fundamental problem with
the way a sail works, NOT a fundamental problem of physics in general.
OTOH, if you use a completely different mechanism which is not simply
re-directing the air flow, it is certainly possible to capture this wind
energy (with a windmill for example), direct it to a propeller operating in
the water, and drive the boat directly into the wind. It's not worth the
expense and effort, but it can be done.
Of course, trying to convince the uneducated is not always easy. It's sort
of trying to convince a fast, but unsophisticated foot runner that you can
go faster using a bicycle. If you have a cave man mentality and if you've
never seen a bike, and if you've never studied bikes in school, you might
naturally argue that a man dragging along 20 to 50 pounds of machinery
couldn't possibly go faster than a man running with only a pair of shorts
on, or in your case ladies underwear.
In summery, just because sail driven craft can't sail directly upwind, does
not mean that a boat with a completely different energy extraction scheme
couldn't do so.
Bob Walters
Now when
Capt. Neal® wrote in message ...
Scott Vernon
Of course this was after he ate his spinach. Does this count?
Scott?
Capt. NealŽ wrote in message ...
>It can't be done or it would have been done already.
Capt. Neal®
look at it.
Popeye could blow on his sails but he would not make the
vessel proceed forward because he was standing on the deck
at the time and any force the he expelled forward into the
sails would be negated by an equal force exerted backwards
by his feet on the deck.
I think everybody in his right mind would agree with that.
Same thing would then apply to a fan mounted on deck and
blowing into the sails to make the boat proceed forward. It
will not work because just as much thrust is pushing the
vessel backwards as forwards.
Now lets put Pete32's windmill on the deck. There is no real
difference between it and the fan mentioned above other than
the fact that rather that turn the wind around and blow it
on the sail, it attempts to turn the wind around and use it
to power a water propeller. It won't work any more than the
fan will work because just as much force is pushing the
vessel backwards as can be developed to push the vessel
forward.
This is with 100 percent efficiency and we all agree 100
percent efficiency is not possible so the vessel will not
even keep its station but will slowly be pushed backwards.
Respectfully,
Capt. Neal
~~~~~~~~~~~~~
Scott Vernon wrote in message
<#CdvOneA$GA.302@cpmsnbbsa05>...
Roger Wollin
<boban...@worldnet.att.net> kerfuffled thusly:
>There was no claim that ice boats could sail directly into the wind, neither
>can sailboats or sail cars (or whatever you call wheeled vehicles). And
>while they can't sail directly into the wind, they are able to easily travel
>faster than the wind, something that a simple mind may have trouble
>understanding.
And if ice-yachts and land-yachts didn't exist there be would a lot of
people saying that sailors of high power skiffs are liars, just
because they claim to exceed wind speed!
Regards
Roger
Capt. Neal®
One can NEVER exceed the APPARENT wind speed in a sailing
craft of any sort. TRUE or actual wind as felt by a
stationary observer--yes, apparent wind--no. The windmill
contraption claims to exceed the apparent wind. I cannot be
done.
Respectfully,
Capt. Neal
~~~~~~~~~~~~~
Roger Wollin wrote in message
<1a=jNySIwMaU2pI...@4ax.com>...
Scott Vernon
Capt. NealŽ wrote ...
Ed Chell
--
Saludos,
Ed Chell
Scott Vernon <SBVE...@email.msn.com> wrote in message news:OvOyq9eA$GA.302@cpmsnbbsa05...
Mike Pupeza VE3EQP
Let's flog this horse one more time, and MAYBE, I can clear it up so that
you CAN understand!
It IS POSSIBLE to have a boat sail DIRECTLY into the wind!
Picture this - a wagon with wheels with a small windmill on it, driving a
very low ratio worm screw drive to the wheels. We can have that wind sucker
spinning at hundreds of RPM, with gearing that'll run over a flea in about
2 minutes, and it'll do it! If the ratio is right, DO YOU DENY that this
contraption CAN MOVE DIRECTLY forward into the wind? If NO, then we can stop
here! We can go away, have a few Beers, and get back to the Crosswords - 3
letter word for Japanese Waist Sash?
If yes, then, at what viscosity, or type of medium, WOULD it be impossible?
Why assuming that we use a PROPELLOR, instead of the geared wheels when the
efficiency of the wheels is less than a prop, then ANY VISCOSITY thicker
than the AIR, driving the Windmill, SHOULD have an optimum ratio, for a
given set of circumstances, and WILL ALSO DRIVE this Vehicle Forward -
DIRECTLY into the wind! If the Vehicle is on a same or lower viscosity
material than the air, then - YES - YOU ARE RIGHT! Is that what you wanted
to hear?
I hope this helps.
Very respectfully,
Mike - crew, cook, sometimes Capt., if I get permission first!
>
Jim - SBSC
>letter word for Japanese Waist Sash
Obi
Jim
Visit the Southern Bay Sailing Club website:
http://hometown.aol.com/winchkid/myhomepage/sports.html
To reply to my postings, you must remove "NOSPAM" from my e-mail address.
Marcus G Bell
Capt. Neal® (Capt...@Bigfoot.com) wrote:
> Nonsense, you can explain it 2000 times and you will still be
> wrong because the auto will never start going on its own any
> more than Pete's fantasy boat will start going directly into the
> wind on its own.
Upon what principles of physics do you base these
statements?
And, it's a red herring anyway. Even a sailboat does not start
going upwind on its own. It requires a sailor to adjust the angles
of the rudder and sails.
> Hey, I just had an idea where I can easily win the cross country
> solar powered automobile race. I will mount one teensy weensy
> speck of a solar cell on the hood of the car and wire it to an
> electric engine so it will qualify as a solar powered auto. Then
> I will sneak over to England and steal Pete32's windmill
> contraption and mount it on the car as well and rig it so it
> will also power the electric motor.
Yeah, yeah, there you go again in your typical fashion with some
attempt at proof counter to truth, using faulty logic rather than
simple laws of physics.
Sorry, but just because nobody has yet found that such a vehicle
would outrace a solar car in a competition with specific rules for
entry, is in no way a disproof that such an entity could exist and
function as stated.
Bob Walters
Capt. NealŽ wrote in message ...
>One can NEVER exceed the APPARENT wind speed in a sailing
>craft of any sort. TRUE or actual wind as felt by a
>stationary observer--yes, apparent wind--no. The windmill
>contraption claims to exceed the apparent wind. I cannot be
>done.
Huh? I missed that post. Please refer me. I think we all agree that, by
definition, you can't exceed the apparent wind. Who's claiming to do so?
I thought the argument was that a windmill extracting energy from the moving
air (wind) and transferring this energy to a water prop could not proceed
directly upwind.
Assume a 10kt North breeze. Your heading is 360. Assume the course and
speed through the water is 360 degrees at 1kt, and the windmill proponents
prevail in their argument.
Any sailor who understands what true and apparent wind are would say that
the true wind is 10 kts, the speed is 1 knot and the apparent wind is 11
knots. Follow? It's simple stuff. Boat speed nowhere near the apparent
wind speed, yet if you could do this, the windmill guys would win the
argument, right?
I don't see where anyone here is arguing that the windmill-craft is claiming
to exceed the apparent wind.
Tell me more about your confusion and I'll try to help you. Unlike lots of
folks lurking at this NG, I don't think you're stupid or dull, merely
uneducated and there's no shame in that.
Unless of course you refuse to be educated.
I get the idea that you're actually quite sharp and easily have the mental
capacity to understand this rather simple concept.
Capt Neal you're crying out for help. Let us give it to you.
Bob Walters
Marcus G Bell
> Apples and oranges, apples and oranges, apples and oranges! One
> can NEVER exceed the APPARENT wind speed in a sailing craft of
> any sort. TRUE or actual wind as felt by a stationary
> observer--yes, apparent wind--no. The windmill contraption
> claims to exceed the apparent wind. I cannot be done.
Let's see. Craft moving 1 knot upwind. True windspeed, 9 knots.
Apparent wind, 10 knots. 1 < 10. The craft does not exceed the
apparent wind.
Care to tell us where the apparent wind comes from on a craft
moving downwind, at an angle of course, but with a VMG faster than
the true wind?
jlrogers
condition for disproving the argument.
Marcus G Bell <be...@mail.med.upenn.edu> wrote in message
news:7s2lbe$4se$1...@netnews.upenn.edu...
jlrogers
Bob Walters <boban...@worldnet.att.net> wrote in message
news:7s2m00$r1q$2...@bgtnsc01.worldnet.att.net...
>
> Assume a 10kt North breeze. Your heading is 360. Assume the course
and
> speed through the water is 360 degrees at 1kt. Any sailor who
Roger Wollin
<Capt...@Bigfoot.com> kerfuffled thusly:
>Apples and oranges, apples and oranges, apples and oranges!
>One can NEVER exceed the APPARENT wind speed in a sailing
>craft of any sort. TRUE or actual wind as felt by a
>stationary observer--yes, apparent wind--no.
Sorry Crappy, when your Coronado 27 was doing 6.5 knots DDW in a 7
knot wind the APPARENT wind would have been 0.5 knots. Once again you
have proved yourself a complete and utter PUTZ!
Disrespectfully
Roger
>The windmill
>contraption claims to exceed the apparent wind. * I * cannot be
>done.
I think you have made a first class job of doing yourself.
Roger Wollin
kerfuffled thusly:
>If you can add 10+(-1) and get 11, he's better off listening to himself.
Um - I know you said a while back that you haven't been sailing for
some time, but your brain has gone severely rusty. If you are heading
360 you are travelling due North. The wind is coming *from* the North,
so if you go due North at 1 knot *into* a 10 knot wind, the apparent
wind *is* 11 knots.
Regards
Roger
Roger Wollin
kerfuffled thusly:
>Carrying an argument to its illogical extreme is sometimes a sufficient
>condition for disproving the argument.
Reductio ad absurdum only works in very limited circumstances, and
making exagarated claims which were not in the original argument is
not one of them.
Roger
Roger Wollin
<Capt...@Bigfoot.com> kerfuffled thusly:
>Now lets put Pete32's windmill on the deck. There is no real
>difference between it and the fan mentioned above other than
>the fact that rather that turn the wind around and blow it
>on the sail, it attempts to turn the wind around and use it
>to power a water propeller. It won't work any more than the
>fan will work because just as much force is pushing the
>vessel backwards as can be developed to push the vessel
>forward.
Oh dear, this is such a masterpiece of illogic that there is no way to
rebut it without entering into the same realms of insanity as its
originator, except to state that the windmill does *not* 'attempt to
turn the wind around' and blow it forward, it merely extracts power
from the wind passing through it, (see Loree Thomas' posts for
explanation), and to remind you that exactly the same conditions apply
to a sail boat, which also could not make progress to windward under
the same theory.
Roger
Marcus G Bell
> Carrying an argument to its illogical extreme is sometimes a
> sufficient condition for disproving the argument.
Of course. It's called reductio ad absurdum.
Inflating the traits of something by ignoring several truths along
the way, and then saying the outcome is impossible based on known
truths, is quite another thing.
Let's try this:
If the Coronado 27 were such a great vessel, Jeff Gordon would
surely have stuck wheels on one and raced it against other wheeled
vehicles in high speed timed events, and NASA would surely have
affixed rocket boosters to one and used it in space exploration.
These things haven't happened, therefore the Coronado 27 must suck
as a boat.
jlrogers
Roger Wollin <mot...@nildram.co.uk> wrote in message
news:DTTlN0TBgNr4Jb...@4ax.com...
> On Sun, 19 Sep 1999 11:49:45 -0500, "jlrogers" <jlr...@hotmail.com>
> kerfuffled thusly:
>
Thomas Stewart
Praise to the prop drive mode and thrusting keel;
Marcus's ideas, he thinks their real!!!
(chorus)
It may be true for all we know
Your solutions sound quite queer.
We hate like hell to dought your word
but your Bull Shit won't go here!!!!!!!!
I'll drink to that also, as this is my last response to this other
tired thread
TO THE WIND THAT BLOWS AND A BOAT THAT GOES,
AND THE LASS WHO LOVES A SAILOR!!!!!
Thanks Capt Keywest-----Btms up
Thom
Philip Allum
<Capt...@Bigfoot.com> writes
>
>Now lets put Pete32's windmill on the deck. There is no real
>difference between it and the fan mentioned above other than
>the fact that rather that turn the wind around and blow it
>on the sail, it attempts to turn the wind around and use it
>to power a water propeller. It won't work any more than the
>fan will work because just as much force is pushing the
>vessel backwards as can be developed to push the vessel
>forward.
>
>percent efficiency is not possible so the vessel will not
>even keep its station but will slowly be pushed backwards.
>
If more than 50% of the total energy hitting the boat can be converted
into thrust through the propeller in the water, the boat will move
forward when pointing directly into the wind.
You are making the wrong assumption that the fan causes windage and,
therefore, resistance to movement. It doesn't. The blades of the
turbine, windmill, call it what you will, are sails and are trimmed for
"reaching".
The only wind resistance to forward movement is the windage of the
structure holding the fan in place, ie the mast.
No one will disagree that the setup we are discussing will move a boat
across the wind. If it can move a boat at 90 degrees to the wind, what
immutable law of physics says that it will not sail at 89 degrees to the
wind, or 88 or 87? If it will move at 87, then why not at 47 or 27 or
07, or 0 degrees? If it is indeed IMPOSSIBLE to sail directly into the
wind, there must be a scientific explanation and it must be possible to
calculate at exactly how many degrees off the true wind, the boat will
cease to move ahead.
We await your calculations.
Personally, I'm not holding my breath.
--
Philip Allum
jlrogers
Philip Allum <p...@eurogrove.demon.co.uk> wrote in message
news:ClloaAAl...@eurogrove.demon.co.uk...
> If more than 50% of the total energy hitting the boat can be converted
> into thrust through the propeller in the water, the boat will move
> forward when pointing directly into the wind.
59% of the energy applied to the turbine can be converted, theoretically
at least. None of the wind applied to the boat and mast is converted.
Capt. Neal®
Philip Allum wrote in message ...
><snipped some>
>
>You are making the wrong assumption that the fan causes
windage and,
>therefore, resistance to movement. It doesn't. The
blades of the
>turbine, windmill, call it what you will, are sails and are
trimmed for
>"reaching".
>
>The only wind resistance to forward movement is the windage
of the
>structure holding the fan in place, ie the mast.
>
Totally incorrect. Anyone who has ever flown an aircraft
knows that a freewheeling propeller creates a very great
amount of drag compared to one that cannot spin.
Respectfully,
Capt. Neal
~~~~~~~~~~~~~
Philip Allum
<Capt...@Bigfoot.com> writes
>
snipped
>Totally incorrect. Anyone who has ever flown an aircraft
>knows that a freewheeling propeller creates a very great
>amount of drag compared to one that cannot spin.
>
>Respectfully,
>Capt. Neal
>~~~~~~~~~~~~~
>
a mechanical link. It's not a problem of physics, its a mechanical
problem - can it be constructed to work in a sufficiently efficient
manner for the propeller in the water to develop enough thrust to
overcome windage and water resistance. It can and has been done.
I'll concede the point, as others have done, that no one has yet managed
to build a rig which will take a boat dead to windward, I mean the
fastest route from point (a) to another point dead to windward of it,
and probably on any other point of sailing, more efficiently than a
conventional (in its broadest sense) mast and sail(s).
If you want to argue that it's probably a futile exercise and that a
large rigid contraption of sufficient size to drive a boat is inherently
unseaworthy, I'll agree with you 100% but that doen't mean it can't work
at all.
I repeat my last post - if there is some law physical law that says it
can't work and we all know that it does work on other points of sailing,
you must be able to produce a formula which calculates at exactly how
many degrees off the wind it will cease to work.
--
Philip Allum
jlrogers
jlrogers
approaches zero?
Philip Allum
<jlr...@hotmail.com> writes
>Would it not just get slower and slower as the angle into the wind
>approaches zero?
>
>
>
>
--
Philip Allum
Marcus G Bell
> > says it can't work and we all know that it does work on other
> > points of sailing, you must be able to produce a formula which
> > calculates at exactly how many degrees off the wind it will
> > cease to work.
jlrogers (jlr...@hotmail.com) wrote:
> Would it not just get slower and slower as the angle into the
> wind approaches zero?
Well, that's a reasonable supposition. In that case, it should be
possible to produce a formula or calculation which has power
available from the wind decreasing as angle from the wind
approaches zero.
We have no trouble accepting that there is power to drive the
vessel across the wind at a 90 degree angle. Not so much trouble
to decrease the angle to 60, then maybe 45, which gives an upwind
component of the velocity. So there is power available to drive
the vessel against the wind, albeit at an angle from the wind. Is
this power somehow affected by the angle the vessel makes with
respect to the wind? I guess it depends on that exctracts the
power from the wind.
Let's set up the opposite scenario. You've ripped your sails and
have to fire up the outboard. Home and beer are upwind from you.
The 5 HP outboard can just hold your position running dead into
the eye of the stiff breeze. To what minimum angle do you have to
bear off before you start to attain some VMG to weather?
Marcus G Bell
> If more than 50% of the total energy hitting the boat can be
> converted into thrust through the propeller in the water, the
> boat will move forward when pointing directly into the wind.
Actually, there is no arbitrary percentage of *energy* which must
be converted to thrust. Energy = thrust X distance, so *thrust*
can be arbitrarily high with a tradoff of distance. Effective
thrust is the quantity which must exceed the force of the wind on
the hull, rigging, and windmill, if the vessel is to accellerate
into the wind. The boat stops accellerating when all forces are
balanced. If there is 100 hp available and I only convert 1% of
it, I can still make enough thrust to push a boat into an
arbitrarily strong headwind. Percentages come in when we start to
assign sizes to things, such that the thing can be realized in
practical dimensions.
JAXAshby
>Let's set up the opposite scenario. You've ripped your sails and
>have to fire up the outboard. Home and beer are upwind from you.
>The 5 HP outboard can just hold your position running dead into
>the eye of the stiff breeze. To what minimum angle do you have to
>bear off before you start to attain some VMG to weather?
Guess what?? You can't make it home. For if the wind and the waves apply the
force of a 5hp motor propeller churning in the water (and on a boat pointed
with its least wind/water resistance in the direction your want to go), no
amount of turning off wind will give more than the thrust the 5hp engine is
capable of (let alone make up for the extra windage of the sideways boat). You
goin' downwind, mon.
Pete Sykes
system on a boat can go pretty much wherever it wants with
the exception of downwind at wind speed.
I wonder how efficient you can make this.
Pete Sykes
Marcus G Bell
> > Let's set up the opposite scenario. You've ripped your sails
> > and have to fire up the outboard. Home and beer are upwind
> > from you. The 5 HP outboard can just hold your position
> > running dead into the eye of the stiff breeze. To what minimum
> > angle do you have to bear off before you start to attain some
> > VMG to weather?
JAXAshby (jaxa...@aol.com) wrote:
> Guess what?? You can't make it home. For if the wind and the
> waves apply the force of a 5hp motor propeller churning in the
> water (and on a boat pointed with its least wind/water
> resistance in the direction your want to go), no amount of
> turning off wind will give more than the thrust the 5hp engine
> is capable of (let alone make up for the extra windage of the
> sideways boat). You goin' downwind, mon.
That's exactly my point.
Therefore, if you are able to make progress upwind running at an
angle to the wind with the outboard whining flat out, you would
make BETTER progress running dead into the wind.
Now, the propeller on the outboard doesn't know whether the wind
drag is coming from a 4 x 8 sheet of plywood or a windmill. Nor
does the prop know if the power comes from an internal combustion
engine or from a windmill, just 'long as it gets its power
somewhere.
So, just like the case of the outboard, the windmill propsailer
probably makes its best progress to weather running dead into the
wind.
Marcus G Bell
> Actually if you think about it. A windmill powering a propulsion
> system on a boat can go pretty much wherever it wants with the
> exception of downwind at wind speed.
Hmmm. What would limit its downwind speed to disallow the speed of
the true wind?
> I wonder how efficient you can make this.
As a practical matter, I'd guess probably not as efficient as a
real sailboat.
Philip Allum
<be...@mail.med.upenn.edu> writes
My last formal Physics and Mechanics lessons are more than 45 years back
and I don't have the jargon any more. I have no problems with what you
say, though.
I was also about to remark that no one has mentioned the size of the
turbine or windmill (sail area) as a factor, assuming that the larger it
is, the more efficient it will be.
Branching of at a slight tangent, do any of those people who have cited
literature, know whether there have been any experiments and published
results of a windmill driving a generator to run an electric motor to
power the propeller?
--
Philip Allum
Douglas King
> > Marcus G Bell writes:
>
> > > Let's set up the opposite scenario. You've ripped your sails
> > > and have to fire up the outboard. Home and beer are upwind
> > > from you. The 5 HP outboard can just hold your position
> > > running dead into the eye of the stiff breeze. To what minimum
> > > angle do you have to bear off before you start to attain some
> > > VMG to weather?
>
> JAXAshby (jaxa...@aol.com) wrote:
>
> > Guess what?? You can't make it home. For if the wind and the
> > waves apply the force of a 5hp motor propeller churning in the
> > water (and on a boat pointed with its least wind/water
> > resistance in the direction your want to go), no amount of
> > turning off wind will give more than the thrust the 5hp engine
> > is capable of (let alone make up for the extra windage of the
> > sideways boat). You goin' downwind, mon.
Marcus G Bell wrote:
> That's exactly my point.
Umm, it grieves me to interject a note of reality here, but that's not
the case.
If 5hp is exactly enough to keep a sailboat in place against a headwind,
that sailboat CAN gain some VMG to windward by turning at an angle.
That's what the underwater foils are for. If the boat is head-to-wind
and sitting still, then there is only the thrust of the motor resists
the drag of the wind. If the boat turns away, the drag vector shifts,
it's straight-astern component shortens, the keel and/or centerboard
provide some resistance to the sideways component of the drag vector;
meanwhile the motors thrust vector is exactly the same relative to the
boat. It is not true that any sailboat will do this, but one with foils
of X efficiency can.
IMHO this does not at all prove it is impossible for a
wind-turbine/propellor driven boat to go directly into the wind. It just
shows that the vectors need to be summed up correctly.
Fresh Breezes- Doug King
--
This is what we look like when we're at our best:
http://freehosting.at.webjump.com/ei/eisboch-webjump/45.htm
Marcus G Bell
> If 5hp is exactly enough to keep a sailboat in place against a
> headwind, that sailboat CAN gain some VMG to windward by turning
> at an angle.
> That's what the underwater foils are for. If the boat is
> head-to-wind and sitting still, then there is only the thrust of
> the motor resists the drag of the wind. If the boat turns away,
> the drag vector shifts, it's straight-astern component shortens,
> the keel and/or centerboard provide some resistance to the
> sideways component of the drag vector; meanwhile the motors
> thrust vector is exactly the same relative to the boat. It is
> not true that any sailboat will do this, but one with foils of X
> efficiency can.
Thanks, Doug.
Both Jax and I were discussing a situation where hull drag in the
water is not greatly dependent on which direction the craft is
pointed as it is blown downwind, or where any increased hull/keel
drag arising from bearing off the wind would be overshadowed by
greatly increased windage. I think what we said holds true for
boats that lack a significant keel (or centerboard), it was
unfurtunate that I set us up with a sailbloat which would probably
have a keel, but this is after all a.s.asa ;-)
I should have said "your keel fell off" instead of "you've ripped
your sails", since upwind progress by sail and outboard would then
both be similarly afflicted ;-)
When running partly across the wind instead of straight into it,
as the keel pushes water downwind, the water resists and pushes
back on the keel with an equal and opposite upwind force. Above
merely resisting leeway, the keel moving through the water may
provide lift in the upwind direction if its angle of attack in the
water is appropriate. These upwind forces just might exceed the
available static thrust of the outboard. If this "newfound" upwind
force is able to match the increased wind drag on the hull, the
boat could make upwind progress by running at an angle instead of
into the wind.
So don't haul in your centerboard thinking its drag slows you down
if you are having trouble motoring into the wind. The centerboard
may actually speed your windward progress if you run at an angle
to the wind.
As for the windmill/propsailer, it was assumed to lack a keel.
Douglas King
> Both Jax and I were discussing a situation where hull drag in the
> water is not greatly dependent on which direction the craft is
> pointed as it is blown downwind, or where any increased hull/keel
> drag arising from bearing off the wind would be overshadowed by
> greatly increased windage. I think what we said holds true for
> boats that lack a significant keel (or centerboard), it was
> unfurtunate that I set us up with a sailbloat which would probably
> have a keel, but this is after all a.s.asa ;-)
Ah, so. Sorry I butted in.
You are correct about this no-keel scenario. And by inference, so is
JAXAshby.
> As for the windmill/propsailer, it was assumed to lack a keel.
Hmm- it seems to me that a wind-propelled boat should have underwater
foils. They may be small, or high-aspect ratio, or or even retractable
like a centerboard. But it's obvious that they will improve it's
efficiency and speed under many conditions, once you start looking at
the vectors involved.
Marcus G Bell
> > I think what we said holds true for boats that lack a
> > significant keel (or centerboard), it was unfurtunate that I
> > set us up with a sailbloat which would probably have a keel,
> > but this is after all a.s.asa ;-)
Douglas King (doug...@mindspring.com) wrote:
> Ah, so. Sorry I butted in. You are correct about this no-keel
> scenario. And by inference, so is JAXAshby.
Apology unnecessary, as your "butt[ing] in" was necessary to clear
up confusion, which furthermore and brought new things to light.
> > As for the windmill/propsailer, it was assumed to lack a
> > keel.
> Hmm- it seems to me that a wind-propelled boat should have
> underwater foils. They may be small, or high-aspect ratio, or or
> even retractable like a centerboard. But it's obvious that they
> will improve it's efficiency and speed under many conditions,
> once you start looking at the vectors involved.
Indeed. It would seem that a bit of a keel to hinder leeway and
provide lift would be most beneficial.
Roger Wollin
<p...@eurogrove.demon.co.uk> kerfuffled thusly:
>You are making the wrong assumption that the fan causes windage and,
>therefore, resistance to movement. It doesn't. The blades of the
>turbine, windmill, call it what you will, are sails and are trimmed for
>"reaching".
>
>The only wind resistance to forward movement is the windage of the
>structure holding the fan in place, ie the mast.
You're wrong there Philip. If you look at the forces on a tubine blade
you can resolve them into two forces at right angles, one at right
angles to the shaft of the turbine, and one parallel to the shaft. The
couple generated by the force at right angles is obviously what makes
the turbine spin and that extracts the power from the wind, but the
force parallel to the shaft is parasitic and, when the boat is head to
wind, adds to the total drag attempting to push the boat backwards.
Regards
Roger
JAXAshby
>Douglas King wrote:
>
>> If 5hp is exactly enough to keep a sailboat in place against a
>> headwind.....
>.....When running partly across the wind instead of straight into it,
>as the keel pushes water downwind, the water resists and pushes
>back on the keel with an equal and opposite upwind force...
The keel makes no difference. The original assumption was that the 5hp
outboard could only produce enough thrust (call thust "X" if you like) to hold
against the force of the wind (call that "Minus X" for it is equal and opposite
X). That means Minus X force from the wind must be overcome by the boat engine
to move anything in the direction of the wind. Point the boat in any
direction, you still need to overcome Minus X. And that means, point in any
direction other than straight into the wind the boat will go down wind because
less than X is opposing Minus X. A sailboat on a windward tack is absorbing
*more* horsepower to go in the direction it is going than it needs to go
straight into the wind. Some of the power goes to push the boat upwind, some
goes to overcome movement and drag sideways.
jlrogers
Roger Wollin <mot...@nildram.co.uk> wrote in message
news:1=nnNy7WfWcxTTE...@4ax.com...
> On Tue, 21 Sep 1999 08:56:18 +0100, Philip Allum
> <p...@eurogrove.demon.co.uk> kerfuffled thusly:
>
> >Branching of at a slight tangent, do any of those people who have
cited
> >literature, know whether there have been any experiments and
published
> >results of a windmill driving a generator to run an electric motor to
> >power the propeller?
>
> The first part is easy, any battery charger manufacturer will give the
> power output for his rig at a given wind speed. I've got a URL
> somewhere, I'll look it up later if you're interested. At the output
> end, the model boat boys would be the ones to contact. Just ask about
> the thrust that is developed by a typical motor/prop combination for a
> given power input. I've already thought about this, just never got
> round to following it up.
>
>
>
>
> Cheers
>
> Roger
Roger Wollin
Roger Wollin
kerfuffled thusly:
>Pete Sykes (pe...@sias.com) wrote:
>
>> Actually if you think about it. A windmill powering a propulsion
>> system on a boat can go pretty much wherever it wants with the
>> exception of downwind at wind speed.
>
>Hmmm. What would limit its downwind speed to disallow the speed of
>the true wind?
>
DDW the wind over the deck would drop to zero at wind speed, hence no
power for the turbine.
Marcus G Bell
> > .....When running partly across the wind instead of straight
> > into it, as the keel pushes water downwind, the water resists
> > and pushes back on the keel with an equal and opposite upwind
> > force...
JAXAshby (jaxa...@aol.com) wrote:
> The keel makes no difference. The original assumption was that
> the 5hp outboard could only produce enough thrust (call thust
> "X" if you like) to hold against the force of the wind (call
> that "Minus X" for it is equal and opposite X). That means Minus
> X force from the wind must be overcome by the boat engine to
> move anything in the direction of the wind. Point the boat in
> any direction, you still need to overcome Minus X.
> And that means, point in any direction other than straight into
> the wind the boat will go down wind because less than X is
> opposing Minus X.
The outboard pushes from stern to bow. When we're running dead to
weather, the wind pushes from bow to stern. When we fall off, the
bow-to-stern push decreases, till at 90 degrees to the wind this
push is zero and all wind force is across the beam. Therefore, the
thrust (X) of the outboard can push the boat through the water,
with some positive component of stern-to-bow velocity, when we
fall off enough.
Is the boat making progress to weather by falling off thus, or is
it simply running at 90 degrees to the wind, regardless of where
it is pointed? Only if there's sufficient resistance to "sideways"
motion of the boat will upwind progress be made. A keel would
provide such resistance, and lift to boot. So the upwind force
vectors are X*sine(theta), lift*cosine(theta), and simple
hull/keel drag. The sum of these can be greater than X, in which
case it can overcome the -X of the wind.
This is just like how an airscrew with insufficient thrust to pull
an airplane straight up from tail to nose, can nevertheless
provide enough thrust that the plane can attain sufficient
airspeed to use lift from the wings to climb. That does work,
right?
> A sailboat on a windward tack is absorbing *more* horsepower to
> go in the direction it is going than it needs to go straight
> into the wind. Some of the power goes to push the boat upwind,
> some goes to overcome movement and drag sideways.
The loss of power to hull drag is certainly more if in addition to
the upwind component, a "crosswind" component is introduced.
However, the cross component allows for upwind lift by a foil,
such as a keel. If the magnitude of lift is greater than its drag,
then it may be advantagous to use the lift to help overcome the
force of the wind, with the tradoff that now we waste power to
moving the hull in the wrong direction.
JAXAshby
>The outboard pushes from stern to bow. When we're running dead to
>weather, the wind pushes from bow to stern. When we fall off, the
>bow-to-stern push decreases, till at 90 degrees to the wind this
>push is zero and all wind force is across the beam. Therefore, the
>thrust (X) of the outboard can push the boat through the water,
>with some positive component of stern-to-bow velocity, when we
>fall off enough.
>
>Is the boat making progress to weather by falling off thus, or is
>it simply running at 90 degrees to the wind, regardless of where
>it is pointed? Only if there's sufficient resistance to "sideways"
>motion of the boat will upwind progress be made. A keel would
>provide such resistance, and lift to boot. So the upwind force
>vectors are X*sine(theta), lift*cosine(theta), and simple
>hull/keel drag. The sum of these can be greater than X, in which
>case it can overcome the -X of the wind.
>
>
Assumptions made: 1.) the outboard pushes directly inline with the keel, and
2.) the keep is symetrical in shape. Therefore, the keel can produce no lift
towards the wind (because the keel must be tilted towards the desired movement
and the driving force (the outboard) must be tilted away.
Marcus G Bell
> Assumptions made: 1.) the outboard pushes directly inline with
> the keel, and 2.) the keep is symetrical in shape. Therefore,
> the keel can produce no lift towards the wind (because the keel
> must be tilted towards the desired movement and the driving
> force (the outboard) must be tilted away.
Assumption 2 I'll buy, but no matter because symmetric foils
nevertheless provide lift. Assumption 1 may or may not be true,
but is of less consequense than the actual angle of attack of the
keel on the water moving past it.
Add the velocity vector of the boat cutting the water dead ahead
with the vector of the wind pushing it sideways a bit, and you get
a vector pointing at an angle with respect to the keel's
centerline. Voila, the keel is moving through the water at an
angle, and therefore it makes lift. Is it enough lift? That's
another question.
Philip Allum
<mot...@nildram.co.uk> writes
>On Mon, 20 Sep 1999 09:14:29 +0100, Philip Allum
><p...@eurogrove.demon.co.uk> kerfuffled thusly:
>
>>You are making the wrong assumption that the fan causes windage and,
>>therefore, resistance to movement. It doesn't. The blades of the
>>turbine, windmill, call it what you will, are sails and are trimmed for
>>"reaching".
>>
>>The only wind resistance to forward movement is the windage of the
>>structure holding the fan in place, ie the mast.
>
>You're wrong there Philip. If you look at the forces on a tubine blade
>you can resolve them into two forces at right angles, one at right
>angles to the shaft of the turbine, and one parallel to the shaft. The
>couple generated by the force at right angles is obviously what makes
>the turbine spin and that extracts the power from the wind, but the
>force parallel to the shaft is parasitic and, when the boat is head to
>wind, adds to the total drag attempting to push the boat backwards.
>
>Regards
>
>Roger
>
What I was thinking of is that the ratio power:windage doesn't change as
the turbine is always at optimum trim, unlike a conventional sail where
the drive:drag ratio decreases as the boat comes closer to the wind.
Regards
--
Philip
Marcus G Bell
<p...@eurogrove.demon.co.uk> wrote:
> > Branching of at a slight tangent, do any of those people who
> > have cited literature, know whether there have been any
> > experiments and published results of a windmill driving a
> > generator to run an electric motor to power the propeller?
Roger Wollin (mot...@nildram.co.uk) wrote:
> The first part is easy, any battery charger manufacturer will
> give the power output for his rig at a given wind speed. I've
> got a URL somewhere, I'll look it up later if you're interested.
> At the output end, the model boat boys would be the ones to
> contact. Just ask about the thrust that is developed by a
> typical motor/prop combination for a given power input. I've
> already thought about this, just never got round to following it
> up.
Electric trolling motor manufacturers make the relation that 36 lb
of thrust is roughly equivalant to a 1 HP gas outboard. But if you
look at the amperage draw and voltage of a 36# thrust trolling
motor, it is not drawing 1 HP of power from the battery. The
trolling motor is propped for efficient thrust, with a big, slow
turning prop, whereas a gas outboard typically has a smaller,
faster turning prop more suited for speed. Here's a link for an
idea of what's out there
http://www.trollmotors.com/mkprices.htm
The specs tell you what to expect in terms of reasonable
thrust/power figures. However, you're not going to get a great
deal of speed from these things, and going through the conversion
of wind->electricity->thrust will cut down on efficiency, and
hence speed.