| Topic: |
Science > Physics |
| User: |
"habshi" |
| Date: |
25 Jul 2005 04:07:32 PM |
| Object: |
Quieter more efficinet wind mill |
excerpt and photo
http://www.netcomposites.com/news.asp?3152
Helical ‘Wind Wandler’ Turbine Provides Quieter Domestic Wind Energy
A novel wind turbine named 'Wind Wandler' by its German designers, is
offering a more feasible domestic wind energy option for urban areas
due to its silent operation.
The helical turbine designed in contrast to the more common bladed
design is claimed to be a more efficient form of developing wind
energy for domestic users. The wind turbine has been given the name
the 'Wind Wandler' and was developed by a small German company called
MatroW based in Ladenburg.
The company's managing director Wilhelm Hermann Josef designed the
Wind Wadler as a means of increasing the efficiency of bladed wind
turbines utlilising modern advances in materials.
The form the developers picked was originally conceived to work in
water, but the availability of modern composites allowed it to be made
somewhat larger and lighter than would previously have been possible.
The first production units consist of two spiral vanes of glass fibre
reinforced materials which are 1m in diameter, 1.39m long and sit in a
hemispherical yoke so they are supported at both ends. Output at 14m/s
is about 1 kW. The disk armature generator is rated at 3.5kW and,
unlike bladed turbines, they do not have to be stopped in high winds.
Rotation speed at 24m/s wind is 1,400 rpm, but remains the same at
30m/s because surplus high speed air then tends to spill round the
rotating turbine. The turbines turn naturally into the wind.
Herr Josef explained that they are 53% efficient, as opposed to 46%
for conventional bladed turbines, and the theoretical maximum
efficiency that can be attained is 59%.
The turbines are designed to be quieter when they rotate, which he
says, is because they have no blade tips to shed vortices. Total
weight of turbine and generator without mast is 39kg. Noise level at
1400 rpm is 42 dBA. The company is selling the units at a price of
6,300 euros each.
When the turbine is operating at high speed, the turbine not only
turns the load but also increases the flywheel speed through the eddy
current coupling. However, when the flywheel is going faster than the
turbine, the flywheel continues to turn the load through the eddy
current coupling, but the mechanical clutch is disengaged so that it
does not try to turn the turbine as well. Coupling the flywheel
through an eddy current coupling greatly reduces peak loads on input
and output shafts and gears.
The wings, stretching out curved in the axial plane and a radial
direction. Because of its light induced resistance, and in comparison
with ordinary systems the effectiveness is much higher.
The special shape of the spiral wings produces a strong reduction in
stream wind loss. Furthermore, it is possible to obtain high rotation
speeds. Different wind directions are no obstacles because WiNDuS
automatically turns into the wind. It is also possible to use the wind
converter outside the specific wind areas. It derives advantage of
weak and turbulent winds. The ‘silent runner’ (about 46 dBA with 1.400
r/min) allows locations in more populated areas.
The Wind Waddler follows a number of recent developments in promoting
wind energy for domestic use. British Gas, the UK energy supplier
recently announced details of its plans to develop domestic energy for
the UK.
Publication Date: 22/07/2005
WWW Link: http://www.windwandler.de
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| User: "habshi" |
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| Title: Re: Quieter more efficinet wind mill |
27 Jul 2005 04:47:40 PM |
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Doesnt a jet engine compress air ? And does that not raise its
tempeature? So if the flying machine is fast enough would that not
cause a plasma to form which is all ions and then as they go through
magnets they generate electricity which is beamed down as microwaves
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| User: "" |
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| Title: Re: Quieter more efficinet wind mill |
27 Jul 2005 08:28:08 PM |
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In sci.physics habshi <habshi@anony.com> wrote:
Doesnt a jet engine compress air ? And does that not raise its
tempeature? So if the flying machine is fast enough would that not
cause a plasma to form which is all ions and then as they go through
magnets they generate electricity which is beamed down as microwaves
Yes, a jet engine compresses air.
Yes, the temperature rises, but mostly from the burning fuel.
No, you do not get a plasma in a jet engine.
The only aircraft that generates a plasma is the space shuttle and
it isn't because of the engines.
Ions going through magnets is babble.
You are a moron.
Post to the correct group, idiot.
--
Jim Pennino
Remove .spam.sux to reply.
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| User: "habshi" |
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| Title: Re: Quieter more efficinet wind mill |
27 Jul 2005 12:21:57 PM |
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What about a radioactive source to ionize the jet stream as it rushes inside the flying
machines , and then beam the microwaves. Let not negativity afflict sci.physics. There is a HUGE
source of energy in the jet stream , more than 100 times what the USA uses each year and surely we
have brains to extract one hundredth of it ??
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| User: "tj Frazir" |
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| Title: Re: Quieter more efficinet wind mill |
27 Jul 2005 03:25:59 PM |
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USA has more water flowing than they know what to do with.
3 terrawatts easy.
BUT the GOV don't want anything that works.
That wount fit the corupt addjendas.
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| User: "T Wake" |
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| Title: Re: Quieter more efficinet wind mill |
27 Jul 2005 03:35:39 PM |
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"tj Frazir" <GravityPhysics@webtv.net> wrote in message
news:6594-42E7EDD7-74@storefull-3217.bay.webtv.net...
boring nonsense
Think of something new. You are now a boring, fantasising fool.
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| User: "" |
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| Title: Re: Quieter more efficinet wind mill |
25 Jul 2005 08:34:20 PM |
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In sci.physics habshi <habshi@anony.com> wrote:
Nothing appropriate for any of the groups posted to because habshi
is an idiot.
Post your windmill crap to sci.energy where someone might care.
Ignorant moron.
--
Jim Pennino
Remove .spam.sux to reply.
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| User: "tj Frazir" |
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| Title: Re: Quieter more efficinet wind mill |
26 Jul 2005 02:24:52 PM |
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Slow speeds work better.
I dont use a gear box. I put a rim out 10 feet in dia and a wheel rides
on it wile its at the end of the gen ac.
4 poles 30 feet long and cloth sails work the best for the buck.
4 sails and any amount of wind is cheep and strong.
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| User: "T Wake" |
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| Title: Re: Quieter more efficinet wind mill |
26 Jul 2005 02:42:04 PM |
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"tj Frazir" <GravityPhysics@webtv.net> wrote in message
news:581-42E68E04-970@storefull-3217.bay.webtv.net...
nothing
You are the slow thing around here. Dullard.
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| User: "Uncle Al" |
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| Title: Re: Quieter more efficinet wind mill |
25 Jul 2005 06:23:01 PM |
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habshi wrote:
excerpt and photo
http://www.netcomposites.com/news.asp?3152
Helical ‘Wind Wandler’ Turbine Provides Quieter Domestic Wind Energy
A novel wind turbine named 'Wind Wandler' by its German designers, is
offering a more feasible domestic wind energy option for urban areas
due to its silent operation.
The helical turbine designed in contrast to the more common bladed
design is claimed to be a more efficient form of developing wind
energy for domestic users. The wind turbine has been given the name
the 'Wind Wandler' and was developed by a small German company called
MatroW based in Ladenburg.
[snip]
Hey idiot wog, what shape are plane propellers? That is the optimum
shape for efficiency in rarefied media.
Hey idiot wog, what shape are boat propellers? That is the optimum
shape for efficiency in dense media.
Hey idiot wog, what shape are turbine rotor/stator blades? That is
the optimum shape for efficiency in intermediate density media.
Hey idiot wog, are any of them "wandlers"?
Hey idiot wog, what about centripetal distortion and disintegration of
the rotor?
Hey idiot wog, how about wholesale bird killing?
Hey idiot wog, yer gonna need two hubs.
--
Uncle Al
http://www.mazepath.com/uncleal/
(Toxic URL! Unsafe for children and most mammals)
http://www.mazepath.com/uncleal/qz.pdf
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| User: "Moose O" |
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| Title: Re: Quieter more efficinet wind mill |
25 Jul 2005 10:43:53 PM |
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"Uncle Al" <UncleAl0@hate.spam.net> wrote in message
news:42E57455.2D9DA3FE@hate.spam.net...
Hey idiot wog, what shape are plane propellers? That is the optimum
shape for efficiency in rarefied media.
Actualy, that's not true.
The most efficient "propeller" for rarified mediums is an infinite number of
infinitely thin blades.
A 2 or 3 or 4 bladed propeller is a compromise.
Mike
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| User: "" |
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| Title: Re: Quieter more efficinet wind mill |
26 Jul 2005 09:04:48 AM |
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Moose O wrote:
"Uncle Al" <UncleAl0@hate.spam.net> wrote in message
news:42E57455.2D9DA3FE@hate.spam.net...
Hey idiot wog, what shape are plane propellers? That is the optimum
shape for efficiency in rarefied media.
Actualy, that's not true.
The most efficient "propeller" for rarified mediums is an infinite number of
infinitely thin blades.
A 2 or 3 or 4 bladed propeller is a compromise.
Mike
Mike--data would suggest that at higher blade wing tip speeds, thinner
and fewer blades might give a better compromise--at my nose level
anyway--but all compromises todate have been less than Betz's
calculated 59.3%. ;-))
For TSRs less than 2, your infinite number of blades idea seems to work
petty well.
Good luck
Tut
Tut
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| User: "Helmut Wabnig " |
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| Title: Re: Quieter more efficinet wind mill |
26 Jul 2005 02:31:55 AM |
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On Mon, 25 Jul 2005 16:23:01 -0700, Uncle Al <UncleAl0@hate.spam.net>
wrote:
habshi wrote:
excerpt and photo
http://www.netcomposites.com/news.asp?3152
Helical ‘Wind Wandler’ Turbine Provides Quieter Domestic Wind Energy
Hey idiot wog, how about wholesale bird killing?
I guess,
a one bladed rotor cuts a stork into 2 pieces
2 bladed rotor cuts a stork into 3 pieces
3 bladed rotor makes stork filets
Wind Wandler makes stork chips.
For me with dip, please
w.
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| User: "" |
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| Title: Re: Quieter more efficinet wind mill |
26 Jul 2005 03:02:32 AM |
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In article <vepbe1hr60n6632ok5s9i33p2k23gi7el6@4ax.com>, Helmut Wabnig <> writes:
On Mon, 25 Jul 2005 16:23:01 -0700, Uncle Al <UncleAl0@hate.spam.net>
wrote:
habshi wrote:
excerpt and photo
http://www.netcomposites.com/news.asp?3152
Helical ‘Wind Wandler’ Turbine Provides Quieter Domestic Wind Energy
Hey idiot wog, how about wholesale bird killing?
I guess,
a one bladed rotor cuts a stork into 2 pieces
2 bladed rotor cuts a stork into 3 pieces
3 bladed rotor makes stork filets
Wind Wandler makes stork chips.
For me with dip, please
Hmm, mind if I join? There should be enough meat there for both of
us.
Mati Meron | "When you argue with a fool,
meron@cars.uchicago.edu | chances are he is doing just the same"
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| User: "Strange Indeed" |
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| Title: Re: Quieter more efficinet wind mill |
25 Jul 2005 08:00:05 PM |
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Uncle Al <UncleAl0@hate.spam.net> wrote in
news:42E57455.2D9DA3FE@hate.spam.net:
habshi wrote:
excerpt and photo
http://www.netcomposites.com/news.asp?3152
Helical ‘Wind Wandler’ Turbine Provides Quieter Domestic Wind Energy
snip
Hey idiot wog, what shape are plane propellers? That is the optimum
shape for efficiency in rarefied media.
snip
I want to see independent testing before I embrace or dismiss this
sort of thing despite the fact that gut feel agrees with your take
on the technical aspects.
"Believe but verify" has never let me down.
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| User: "Autymn D. C." |
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| Title: Re: Quieter more efficinet wind mill |
26 Jul 2005 07:38:20 PM |
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Uncle Al wrote:
Hey idiot wog, what shape are plane propellers? That is the optimum
shape for efficiency in rarefied media.
Hey idiot wog, what shape are boat propellers? That is the optimum
shape for efficiency in dense media.
Hey idiot wog, what shape are turbine rotor/stator blades? That is
the optimum shape for efficiency in intermediate density media.
Hey idiot wog, are any of them "wandlers"?
Hey idiot Schwartz sheep, what's wrong with your head? You can't take
enough of a beating from me that you had to call for more? You must be
too stupid to even know how to do the many efficiency evaluations.
Yes, there are more than one! They are by blade inner room, blade
outer room, blade length, blade swath, blade width, blade pitch, blade
depth, blade speed, blade heft, blade weight, blade ward, blade seek,
blade cost, and blade prop. Those propellors were built for efficient
inner room, length, pitch, speed, heft, weight, ward, cost, and prop,
disregarding everything else as long as the output power overcame their
crappy overall efficiency. They don't even put a ring or funnel around
the blades to reduce the air's catastrofic spill off the tips. More
swath and depth mean more wind, dumbass! Why don't you ever give
numbers with your uppity messages? Because you'd be forced to delete
your own.
Hey idiot wog, what about centripetal distortion and disintegration of
the rotor?
Hey idiot wog, how about wholesale bird killing?
Hey idiot wog, yer gonna need two hubs.
You couldn't read or count high enough to deal with the next-to-last
paragraf:
The special shape of the spiral wings produces a strong reduction in
stream wind loss. Furthermore, it is possible to obtain high rotation
speeds. Different wind directions are no obstacles because WiNDuS
automatically turns into the wind. It is also possible to use the wind
converter outside the specific wind areas. It derives advantage of weak
and turbulent winds. The 'silent runner' (about 46 dBA with 1.400
r/min) allows locations in more populated areas.
Those who would set up the generator in tornado country are too poor
and dumb to try. The blind and dumb birds who fly into whirling blades
can be catfood. Behold mine. They should pay me for pest control.
-Aut
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| User: "tj Frazir" |
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| Title: Re: Quieter more efficinet wind mill |
26 Jul 2005 10:17:48 PM |
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Sheet sail mills turn slow and birds like them .
They are dirt cheep , and strong .
If the wind blows a sail out its one tie to fix it.
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| User: "RichD" |
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| Title: Propellor vs. paddle, was Re: Quieter more efficinet wind mill |
26 Jul 2005 11:23:12 PM |
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Uncle Al wrote:
http://www.netcomposites.com/news.asp?3152
Helical 'Wind Wandler' Turbine Provides Quieter Domestic Wind Energy
A novel wind turbine named 'Wind Wandler' by its German
designers, is offering a more feasible domestic wind energy
option for urban areas due to its silent operation.
Hey idiot wog, what shape are boat propellers? That is the
optimum shape for efficiency in dense media.
This brings up a question which has bugged me for a while.
What makes a screw prop superior to a paddle wheel, as
used on the old river boats? The paddle wheel pushes
directly against the water, it's Newton's 3rd Law in
the most direct form. How can you get more efficient than that?
--
Rich
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| User: "Richard Henry" |
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| Title: Re: Propellor vs. paddle, was Re: Quieter more efficinet wind mill |
26 Jul 2005 11:45:40 PM |
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"RichD" <r_delaney2001@yahoo.com> wrote in message
news:1122438192.574567.115860@g43g2000cwa.googlegroups.com...
Uncle Al wrote:
http://www.netcomposites.com/news.asp?3152
Helical 'Wind Wandler' Turbine Provides Quieter Domestic Wind Energy
A novel wind turbine named 'Wind Wandler' by its German
designers, is offering a more feasible domestic wind energy
option for urban areas due to its silent operation.
Hey idiot wog, what shape are boat propellers? That is the
optimum shape for efficiency in dense media.
This brings up a question which has bugged me for a while.
What makes a screw prop superior to a paddle wheel, as
used on the old river boats? The paddle wheel pushes
directly against the water, it's Newton's 3rd Law in
the most direct form. How can you get more efficient than that?
It's all part of the vast energy-wasting conspiracy.
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| User: "N:dlzc D:aol T:com \dlzc\ N: dlzc1 D:cox" |
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| Title: Re: Propellor vs. paddle, was Re: Quieter more efficinet wind mill |
27 Jul 2005 12:48:03 AM |
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Dear RichD:
"RichD" <r_delaney2001@yahoo.com> wrote in message
news:1122438192.574567.115860@g43g2000cwa.googlegroups.com...
....
This brings up a question which has bugged me for a while.
What makes a screw prop superior to a paddle wheel, as
used on the old river boats? The paddle wheel pushes
directly against the water, it's Newton's 3rd Law in
the most direct form. How can you get more efficient than
that?
A screw prop (and a turbine, and a fan) directs flow for the
entire rotation, with "little" air lost off the tips (depending
on loading etc.). A paddle wheel directs flow for only one
direction, for about 1/3 the total rotation, has to be removed
from the fluid to be driven for the rest of the time, and loses
fluid off of *at least* three sides.
The paddle wheel has slow speed, and large area going for it, so
is good as a "cave man" effort... however graceful and beautiful
they might be.
Additionally, I don't think they carve up wildlife quite as
randomly as props do, but I don't know if that is due to the
prevalence of props...
David A. Smith
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| User: "G=EMC^2 Glazier" |
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| Title: Re: Propeller vs. paddle, was Re: Quieter more efficinet wind mill |
27 Jul 2005 01:09:46 PM |
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Having built a paddle boat from scratch I like it for these reasons. It
is always half out of water.Very efficient because it works like a
turbine. very quite. Can rub into the lake bottom and not damage itself.
all its mechanism is above the water line. Its great for trolling.
I geared it to a ten speed bike,and it goes fast with little effort.
Show you picture of me and the boat at no charge;. Gave the planes to
the Florida Sea Scouts Costs $40 to build and is a nice family Summer
project. Can't sink Bert
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| User: "John Popelish" |
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| Title: Re: Propellor vs. paddle, was Re: Quieter more efficinet wind mill |
27 Jul 2005 12:15:08 AM |
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RichD wrote:
Uncle Al wrote:
http://www.netcomposites.com/news.asp?3152
Helical 'Wind Wandler' Turbine Provides Quieter Domestic Wind Energy
A novel wind turbine named 'Wind Wandler' by its German
designers, is offering a more feasible domestic wind energy
option for urban areas due to its silent operation.
Hey idiot wog, what shape are boat propellers? That is the
optimum shape for efficiency in dense media.
This brings up a question which has bugged me for a while.
What makes a screw prop superior to a paddle wheel, as
used on the old river boats? The paddle wheel pushes
directly against the water, it's Newton's 3rd Law in
the most direct form. How can you get more efficient than that?
It is all about the edges, the dipping in and rising back out.
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| User: "tj Frazir" |
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| Title: Re: Propellor vs. paddle, was Re: Quieter more efficinet wind mill |
27 Jul 2005 12:39:04 AM |
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Its hard to steer a paddle boat.
A prop is easyer and stays under water more.
Its less drag .
Thier outputs are exsacty the same.
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| User: "RichD" |
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| Title: Re: Propellor vs. paddle, was Re: Quieter more efficinet wind mill |
27 Jul 2005 01:23:29 AM |
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John Popelish wrote:
http://www.netcomposites.com/news.asp?3152
Helical 'Wind Wandler' Turbine Provides Quieter Domestic Wind Energy
Hey idiot wog, what shape are boat propellers? That is the
optimum shape for efficiency in dense media.
This brings up a question which has bugged me for a while.
What makes a screw prop superior to a paddle wheel, as
used on the old river boats? The paddle wheel pushes
directly against the water, it's Newton's 3rd Law in
the most direct form. How can you get more efficient than that?
It is all about the edges, the dipping in and rising back out.
Something about vortices and turbulence?
--
Rich
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| User: "N:dlzc D:aol T:com \dlzc\ N: dlzc1 D:cox" |
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| Title: Re: Propellor vs. paddle, was Re: Quieter more efficinet wind mill |
27 Jul 2005 09:11:48 PM |
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Dear RichD:
"RichD" <r_delaney2001@yahoo.com> wrote in message
news:1122445409.799375.304960@g44g2000cwa.googlegroups.com...
John Popelish wrote:
http://www.netcomposites.com/news.asp?3152
Helical 'Wind Wandler' Turbine Provides Quieter Domestic
Wind Energy
Hey idiot wog, what shape are boat propellers? That is the
optimum shape for efficiency in dense media.
This brings up a question which has bugged me for a while.
What makes a screw prop superior to a paddle wheel, as
used on the old river boats? The paddle wheel pushes
directly against the water, it's Newton's 3rd Law in
the most direct form. How can you get more efficient than
that?
It is all about the edges, the dipping in and rising back out.
Something about vortices and turbulence?
The directed force trying to lift the boat on paddle entry, and
trying to pull it under on paddle exit. The significant
differences between paddle speed and water speed at entry and
exit.
Because props have vortices and turbulence at work as well.
David A. Smith
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| User: "John Popelish" |
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| Title: Re: Propellor vs. paddle, was Re: Quieter more efficinet wind mill |
27 Jul 2005 11:23:12 PM |
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N:dlzc D:aol T:com (dlzc) wrote:
Dear RichD:
"RichD" <r_delaney2001@yahoo.com> wrote in message
news:1122445409.799375.304960@g44g2000cwa.googlegroups.com...
John Popelish wrote:
http://www.netcomposites.com/news.asp?3152
Helical 'Wind Wandler' Turbine Provides Quieter Domestic
Wind Energy
Hey idiot wog, what shape are boat propellers? That is the
optimum shape for efficiency in dense media.
This brings up a question which has bugged me for a while.
What makes a screw prop superior to a paddle wheel, as
used on the old river boats? The paddle wheel pushes
directly against the water, it's Newton's 3rd Law in
the most direct form. How can you get more efficient than
that?
It is all about the edges, the dipping in and rising back out.
Something about vortices and turbulence?
The directed force trying to lift the boat on paddle entry, and
trying to pull it under on paddle exit. The significant
differences between paddle speed and water speed at entry and
exit.
Because props have vortices and turbulence at work as well.
I was just having a bit of fun with my answer.
Keep in mind that, according to Newton's 3rd, you produce force when
you accelerate a mass. The paddle wheel is moving with an essentially
constant speed with respect to the water, so it accelerates the water
caught between the blades, only as it slaps the surface (with lots of
useless splashing). From then on, the blades and water are moving at
a nearly constant speed, so no acceleration, no force (except for the
outside surfaces dragging against slower moving water.) Then the
paddles lift a lot of water and it pours and splashes around, none of
which energy absorbing stuff produces force to move the boat.
A well designed prop, on the other hand, knifes into a mass of water
without much disturbance (the angle of attack nearly matching the
angle produced by forward motion of the boat and rotary motion of the
prop blade), then the water slides along a changing attack of angle of
attack that sweeps that water backward in a smooth acceleration,
throwing it behind the next blade's wash. That smooth acceleration
given to packets of water produce a smooth and efficient force.
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| User: "Strange Indeed" |
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| Title: Re: Propellor vs. paddle, was Re: Quieter more efficinet wind mill |
28 Jul 2005 06:57:44 AM |
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John Popelish <jpopelish@rica.net> wrote in
news:EMqdnYYvRO-8x3XfRVn-og@adelphia.com:
I was just having a bit of fun with my answer.
Keep in mind that, according to Newton's 3rd, you produce force when
you accelerate a mass.
"Produce force"?
The paddle wheel is moving with an essentially
constant speed with respect to the water, so it accelerates the water
caught between the blades, only as it slaps the surface
I think you better revisit your thinking. In addition to gleaning a
better understanding what "acceleration" is you might also take a
look at centrifugal pumps and consider all the modes in which a
paddle wheel moves water. Consider also the volume of water being
moved by a paddle boat.
(with lots of useless splashing).
Inefficiency prevails in all mechanical devices. Paddle wheels
are rather primitive but they did represent an acceptable low
tech solution in their heyday. For extra points calculate the
number of Roman slaves at oars they could have replaced using
one paddle boat. For social science class discuss the
ramifications to European timber had paddle boats been in use
from early Roman times onward. Would shipboard slaves have been
replaced one for one by land based slaves in the timber and
firewood transport industry or would steam driven paddle boats
created a manpower disadvantage if the paddle boat was the only
comparatively advanced technology available to early Romans?
From then on, the blades and water are moving at
a nearly constant speed, so no acceleration, no force (except for the
outside surfaces dragging against slower moving water.)
Please define acceleration.
Then the
paddles lift a lot of water and it pours and splashes around, none of
which energy absorbing stuff produces force to move the boat.
A well designed prop, on the other hand, knifes into a mass of water
without much disturbance (the angle of attack nearly matching the
angle produced by forward motion of the boat and rotary motion of the
prop blade), then the water slides along a changing attack of angle of
attack that sweeps that water backward in a smooth acceleration,
throwing it behind the next blade's wash. That smooth acceleration
given to packets of water produce a smooth and efficient force.
Look at variable pitch (aircraft) props and the reason for them. Air
and water are both fluids. Consider the efficiency of a properly
used oar. Would a paddle holding the paddles (consider tank tracks)
in a vertical position been more efficient?
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| User: "N:dlzc D:aol T:com \dlzc\ N: dlzc1 D:cox" |
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| Title: Re: Propellor vs. paddle, was Re: Quieter more efficinet wind mill |
28 Jul 2005 08:15:21 PM |
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Dear Strange Indeed:
"Strange Indeed" <strange@none.com> wrote in message
news:Xns96A15F43F40Dstrangenonecom@63.223.5.248...
John Popelish <jpopelish@rica.net> wrote in
news:EMqdnYYvRO-8x3XfRVn-og@adelphia.com:
I was just having a bit of fun with my answer.
Keep in mind that, according to Newton's 3rd, you
produce force when you accelerate a mass.
"Produce force"?
"Equal and opposite reaction"
The paddle wheel is moving with an essentially
constant speed with respect to the water, so it
accelerates the water caught between the blades,
only as it slaps the surface
I think you better revisit your thinking. In addition
to gleaning a better understanding what
"acceleration" is you might also take a look at
centrifugal pumps and consider all the modes in
which a paddle wheel moves water.
Have you actually seen how a centrifugal pump works? It has much
more in common with a propeller than a paddle wheel. Now the
silly little pumps that are used to circulate domestic hot
water... those *are* like paddle wheels.
Consider also the volume of water being
moved by a paddle boat.
And how much of that volume (per paddle stroke) is actually
directed rearwards...
....
From then on, the blades and water are moving at
a nearly constant speed, so no acceleration, no force
(except for the outside surfaces dragging against
slower moving water.)
Please define acceleration.
I assumed he meant the water adjacent to the paddle had the same
relative speed as the paddle. A very large "boundary layer", if
you will.
Then the
paddles lift a lot of water and it pours and splashes
around, none of which energy absorbing stuff
produces force to move the boat.
A well designed prop, on the other hand, knifes into
a mass of water without much disturbance (the
angle of attack nearly matching the angle produced
by forward motion of the boat and rotary motion of the
prop blade), then the water slides along a changing
attack of angle of attack that sweeps that water
backward in a smooth acceleration, throwing it behind
the next blade's wash. That smooth acceleration
given to packets of water produce a smooth and
efficient force.
Look at variable pitch (aircraft) props and the reason for
them. Air and water are both fluids. Consider the
efficiency of a properly used oar. Would a paddle
holding the paddles (consider tank tracks) in a
vertical position been more efficient?
Yes, assuming the mechanism that keeps the vertical alignment,
and uniform "just a little more than boat speed when in liquid"
didn't eat all your gains.
David A. Smith
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| User: "Strange Indeed" |
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| Title: Re: Propellor vs. paddle, was Re: Quieter more efficinet wind mill |
28 Jul 2005 08:07:47 PM |
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"N:dlzc D:aol T:com \(dlzc\)" <N: dlzc1 D:cox T:net@nospam.com> wrote in
news:CqfGe.178927$Qo.53699@fed1read01:
Have you actually seen how a centrifugal pump works? It has much
more in common with a propeller than a paddle wheel.
Men and monkeys have things in common too, some more than others.
Now the
silly little pumps that are used to circulate domestic hot
water... those *are* like paddle wheels.
It is apparent that you felt qualified to respond although that
fact, standing alone, isn't very interesting. You have this
characteristic in common with many others, some of whom actually
are qualified.
Having something in common is often not worthy of notice, possibly
more often than not.
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| User: "N:dlzc D:aol T:com \dlzc\ N: dlzc1 D:cox" |
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| Title: Re: Propellor vs. paddle, was Re: Quieter more efficinet wind mill |
28 Jul 2005 10:44:36 PM |
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Dear Strange Indeed:
"Strange Indeed" <strange@none.com> wrote in message
news:Xns96A1E51D69FCFstrangenonecom@63.223.5.248...
"N:dlzc D:aol T:com \(dlzc\)" <N: dlzc1 D:cox T:net@nospam.com>
wrote in
news:CqfGe.178927$Qo.53699@fed1read01:
Have you actually seen how a centrifugal pump works?
It has much more in common with a propeller than a
paddle wheel.
Men and monkeys have things in common too, some
more than others.
Ah, so you say "I was trying to get John's goat, and I don't like
interruptions". Got it.
Now the
silly little pumps that are used to circulate domestic hot
water... those *are* like paddle wheels.
It is apparent that you felt qualified to respond although that
fact, standing alone, isn't very interesting. You have this
characteristic in common with many others, some of whom
actually are qualified.
I see that you imagine those qualities in others, that you refuse
to see in yourself. How sad.
Having something in common is often not worthy of notice,
possibly more often than not.
Yeah.
David A. Smith
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| User: "John Popelish" |
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| Title: Re: Propellor vs. paddle, was Re: Quieter more efficinet wind mill |
28 Jul 2005 11:38:13 PM |
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N:dlzc D:aol T:com (dlzc) wrote:
Dear Strange Indeed:
(snip)
Men and monkeys have things in common too, some
more than others.
Ah, so you say "I was trying to get John's goat, and I don't like
interruptions". Got it.
(snip)
I've never owned a goat.
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