wheel cover turbine

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A tire drags air along it's rim, this airstream becomes thicker and
more violent when you go faster. I was thinking perhaps it is possible
to find a way to cut this Mohawk of air into a more useful shape.

I've some what illustrated my idea here.

http://gabydewilde.googlepages.com/wheel-cover-turbine

Please share me your thoughts on this.

Thank you.

:-)

On Dec 21, 12:29�pm, "gdewi...@gmail.com" <gdewi...@gmail.com> wrote:
> A tire drags air along it's rim, this airstream becomes thicker and
> more violent when you go faster. I was thinking perhaps it is possible
> to find a way to cut this Mohawk of air into a more useful shape.

The air pumping effect is at its worst with slick tires because of the
boundary layer.

Tread patterns will break up the boundary layer and cause turbulent
flow.

Another way to break up the boundary layer is by using a strategically
positioned
"trip wire" such as model airplane pylon racers employ.

Sportsracing cars using treadless tires will have louvers in the tops
of the fenders to reduce drag caused by the tires acting as air pumps.

On Dec 21, 11:20 pm, Buteo lineatus <Buteo.linea...@gmail.com> wrote:
> On Dec 21, 12:29�pm, "gdewi...@gmail.com" <gdewi...@gmail.com> wrote:
>
> > A tire drags air along it's rim, this airstream becomes thicker and
> > more violent when you go faster. I was thinking perhaps it is possible
> > to find a way to cut this Mohawk of air into a more useful shape.
>
> The air pumping effect is at its worst with slick tires because of the
> boundary layer.
>
> Tread patterns will break up the boundary layer and cause turbulent
> flow.
>
> Another way to break up the boundary layer is by using a strategically
> positioned
> "trip wire" such as model airplane pylon racers employ.
>
> Sportsracing cars using treadless tires will have louvers in the tops
> of the fenders to reduce drag caused by the tires acting as air pumps.

Hello,

Thanks for the references. I confess I don't know much about the
topic.

To me it seems like a simple flexible extension at the front of the
rear wheel cover (like in my illustration) would suffer a downwards
force. As this would tend to bend the extension forwards it should
create some trust. The boundary layer flow is already squashed into
the ground, I don't think it can get much worse application as that.

I imagine the extension can fit around the tire quite tightly. If it
makes contact it should just bend forwards a bit without touching the
ground. Could even put a small wheel on it to push against the tire.

By gradually making the circle smaller the air accelerates around the
rim. Like a ballerina pulling her arms in.

What do you think?

Would that make the boundary layer drag go faster as the tire?

If so, would it create any note-worthy trust?

http://gabydewilde.googlepages.com/wheel-cover-turbine
gabydewilde - wheel cover turbine

On Dec 21, 5:01 pm, "gdewi...@gmail.com" <gdewi...@gmail.com> wrote:

> If so, would it create any note-worthy trust?

Dear Gaby,

No, the last noteworthy trust in bicycling was laid to rest long
before 1900 when Gormully won its lawsuit (involving whale-oil lamps,
to show how the legal mind works) against Pope:

http://velonews.com/news/fea/7550.0.html

http://velonews.com/news/fea/7573.0.html

http://www.velonews.com/news/fea/7608.0.html

However, if you meant "thrust" (but not as Mr. Dooley meant), then the
answer is that of course you can hook up a fan to a bicycle crank and
produce thrust. That's how the Gossamer Condor managed to fly. But you
can't produce as much thrust as the power required to run the fan.

Cheers,

Carl Fogel

On Dec 21, 4:01�pm, "gdewi...@gmail.com" <gdewi...@gmail.com> wrote:

> Thanks for the references. I confess I don't know much about the
> topic.

I think you should study up on boundary layer, Reynolds numbers,
laminar flow, turbulent flow, Coanda effect, and Tesla boundary layer
pumps before considering any technological solutions if you're trying
to set some kind of record with a bicycle.
>
> To me it seems like a simple flexible extension at the front of the
> rear wheel cover (like in my illustration) would suffer a downwards
> force. As this would tend to bend the extension forwards it should
> create some trust.

Yes, it could create some small amount of thrust, but you have to
realize that the dynamic pressure of air = density ratio X mass of air
X velocity in ft/sec^2 X cross-sectional area pf the stream

The mass of air is so low and the velocity of the air pumped by the
tire is very low,
so the dynamic pressure will be small.

The boundary layer flow is already squashed into
> the ground, I don't think it can get much worse application as that.

No, the boundary layer is viscous and stays attached to the rotating
tire as long as flow in laminar. The larger stream of air outside the
boundary layer would be moving slower than the air stuck in the
boundary layer.

> By gradually making the circle smaller the air accelerates around the
> rim. Like a ballerina pulling her arms in.

You're thinking of angular momentum, and I doubt if the polar moment
of inertia of a mass of air amounts to anything. You can google up
"flywheel" at Wikipedia to study that subject.

> Would that make the boundary layer drag go faster as the tire?
>
> If so, would it create any note-worthy trust?

I doubt it. The fastest dustbin-faired downhill bicycle I ever saw
only went about 130 mph. With 32-inch diameter wheels, the RPM at 130
is only 1365 RPM.

But, if you study Tesla boundary layer pumps you can get some idea of
how fast the disks have turn to move an appreciable amount of air.

On Dec 22, 1:22 am, carlfo...@comcast.net wrote:
> On Dec 21, 5:01 pm, "gdewi...@gmail.com" <gdewi...@gmail.com> wrote:
>
> > If so, would it create any note-worthy trust?
>
> Dear Gaby,
>
> No, the last noteworthy trust in bicycling was laid to rest long
> before 1900 when Gormully won its lawsuit (involving whale-oil lamps,
> to show how the legal mind works) against Pope:
>
Hello Carl,

I love reading old patents. Some how the grammar doesn't disturb me at
all. (lol) Today "pope" makes for an excellent bicycle patent search
keyword.

Reading around those it seems the chain drive defeated the axle driven
system though production cost? We have 100 years worth of patents
claiming an axle is more efficient? How hilarious?

> http://velonews.com/news/fea/7550.0.html
>
> http://velonews.com/news/fea/7573.0.html
>
> http://www.velonews.com/news/fea/7608.0.html
>
> However, if you meant "thrust" (but not as Mr. Dooley meant), then the
> answer is that of course you can hook up a fan to a bicycle crank and
> produce thrust. That's how the Gossamer Condor managed to fly. But you
> can't produce as much thrust as the power required to run the fan.
>

Oh but you are wrong, the energy output of the thrust depends mainly
on the speed and direction of the wind.

So with the wind in your back we can divert energy straight from the
wheels onto a propeller and you will go faster. Having the wind in
your face on the other hand will make thrust increasingly less
interesting. Here it would be smarter to convert the wind energy
(back) onto the wheels.

In the case of our wheel case it could have a valve to take in extra
air when it's desirable. I guess I'm wondering if a wheel can be a
good propeller.

http://gabydewilde.googlepages.com/wheel-cover-turbine
gabydewilde - wheel cover turbine

On Fri, 21 Dec 2007 19:26:13 -0800 (PST), "gdewilde@gmail.com"
<gdewilde@gmail.com> wrote:

> I guess I'm wondering if a wheel can be a
>good propeller.

Dear Gaby,

Nope.

Cheers,

Carl Fogel

On Dec 22, 2:02 am, Buteo lineatus <Buteo.linea...@gmail.com> wrote:
> On Dec 21, 4:01�pm, "gdewi...@gmail.com" <gdewi...@gmail.com> wrote:
>
> > Thanks for the references. I confess I don't know much about the
> > topic.
>
> I think you should study up on boundary layer, Reynolds numbers,
> laminar flow, turbulent flow, Coanda effect, and Tesla boundary layer
> pumps before considering any technological solutions if you're trying
> to set some kind of record with a bicycle.
>

You are of course right but I'm just being curious. Who knows what we
can come up with.

> > To me it seems like a simple flexible extension at the front of the
> > rear wheel cover (like in my illustration) would suffer a downwards
> > force. As this would tend to bend the extension forwards it should
> > create some trust.
>
> Yes, it could create some small amount of thrust, but you have to
> realize that the dynamic pressure of air = density ratio X mass of air
> X velocity in ft/sec^2 X cross-sectional area pf the stream
>
> The mass of air is so low and the velocity of the air pumped by the
> tire is very low,
> so the dynamic pressure will be small.
>
> > The boundary layer flow is already squashed into
> > the ground, I don't think it can get much worse application as that.
>
> No, the boundary layer is viscous and stays attached to the rotating
> tire as long as flow in laminar. The larger stream of air outside the
> boundary layer would be moving slower than the air stuck in the
> boundary layer.
>

I didn't word that correctly. The layer closest to the tire would go
almost as fast as the tire. The first one is glued onto the tire,
every next layer goes a bit slower.

I was suggesting to gradually compress the slowest part so that it
goes faster as the medium flow. In stead of having a solid frame
around the wheel it would then be sealed in (some what) moving air.

> > By gradually making the circle smaller the air accelerates around the
> > rim. Like a ballerina pulling her arms in.
>
> You're thinking of angular momentum, and I doubt if the polar moment
> of inertia of a mass of air amounts to anything. You can google up
> "flywheel" at Wikipedia to study that subject.
>

Only the fastest moving layer should remain on the tire. The slower
layers create drag on the ground and cross the air flowing around the
bike.(underneath)

So it would be thrust in exchange for drag.

If it's really worth it we should investigate how to create additional
drag with the wheel.

So far I found this patent from Mr Barefoot, not entirely sure how it
works but the toy makes lift from spin and the patent makes
interesting citations from sailing and flying machines.
http://www.google.com/patents?vid=USPAT4051622

> > Would that make the boundary layer drag go faster as the tire?
>
> > If so, would it create any note-worthy trust?
>
> I doubt it. The fastest dustbin-faired downhill bicycle I ever saw
> only went about 130 mph. With 32-inch diameter wheels, the RPM at 130
> is only 1365 RPM.
>
> But, if you study Tesla boundary layer pumps you can get some idea of
> how fast the disks have turn to move an appreciable amount of air.

I started thinking about this when I saw the wind coming from the rear
wheel of a bicycle riding in front of me.

The owner had covered the back seat in aluminum foil (as a joke) but
the foil was blowing upwards from the tire. He wasn't going that fast
and there was at least 15 cm of space between the wheel and the
spontaneously self assembled measurement apparatus. :-)

As that was just a slow moving bike I became curious how much wind
motor cycles blow into the ground. The tire isn't quite flat like a
Tesla turbine.

Still that doesn't mean there is note worthy action to be exploited.

I'm just curious :-)

http://gabydewilde.googlepages.com/wheel-cover-turbine
gabydewilde - wheel cover turbine

On Dec 22, 4:39 am, carlfo...@comcast.net wrote:
> On Fri, 21 Dec 2007 19:26:13 -0800 (PST), "gdewi...@gmail.com"
>
> <gdewi...@gmail.com> wrote:
> > I guess I'm wondering if a wheel can be a
> >good propeller.
>
> Dear Gaby,
>
> Nope.
>

This is an interesting answer.

We both know you are guessing Carl.

This is actually the main reason I look at things like this.

No offence but your guess is so vastly inaccurate it's just silly. I
can think of a hundred ways to make a wheel that is also a propeller.
It's just not possible for you to make claims about any of those
designs before you see them.

The "nope" you talk of drains the effort going towards such
investigation.

It gives away how you have never tried to design one.

Don't get me wrong.

I'm not claiming such a thing is possible. I indeed can't provide one
that works jet. But could you explain on what you base your
impossibility claim?

In some way I'm grateful there are so much treasures buried at the
surface. Honestly, the more amazing things I wouldn't even dare
talking about. 100 to 1 the only replies will be of the "nope" kind.

My personal favorite are people who say you cant sail up the wind. lol

If your answer is "it's never been tried", how does that mean it's
impossible? If it's never been looked into, is it therefor
impossible?

It's so ironic?

But thanks for your comment.

http://gabydewilde.googlepages.com/wheel-cover-turbine
gabydewilde - wheel cover turbine

On Fri, 21 Dec 2007 20:17:47 -0800 (PST), "gdewilde@gmail.com"
<gdewilde@gmail.com> wrote:

>On Dec 22, 4:39 am, carlfo...@comcast.net wrote:
>> On Fri, 21 Dec 2007 19:26:13 -0800 (PST), "gdewi...@gmail.com"
>>
>> <gdewi...@gmail.com> wrote:
>> > I guess I'm wondering if a wheel can be a
>> >good propeller.
>>
>> Dear Gaby,
>>
>> Nope.
>>
>We both know you are guessing Carl.

Dear Gaby,

Nope.

Cheers,

Carl Fogel

On Dec 21, 9:29 pm, "gdewi...@gmail.com" <gdewi...@gmail.com> wrote:
> A tire drags air along it's rim, this airstream becomes thicker and
> more violent when you go faster. I was thinking perhaps it is possible
> to find a way to cut this Mohawk of air into a more useful shape.
>
> I've some what illustrated my idea here.
>
> http://gabydewilde.googlepages.com/wheel-cover-turbine
>
> Please share me your thoughts on this.
>
> Thank you.
>
> :-)


http://en.wikipedia.org/wiki/Voith-Schneider
"The Voith Schneider propeller (VSP), also known as a cycloid drive is
a specialized marine propulsion system. It is highly maneuverable,
being able to change the direction of its thrust almost
instantaneously. It is widely used on tugs and ferries."

http://en.wikipedia.org/wiki/Helicopter_flight_controls#Cyclic
"The control is called the cyclic because it changes the pitch of the
rotor blades cyclically. That is, the pitch or feathering angle of the
rotor blades change depending upon their position as they rotate
around the hub so that all blades will change their angle the same
amount at the same point in the cycle. The change in cyclic pitch has
the effect of changing the angle of attack and thus the lift generated
by a single blade as it moves around the rotor disk. This in turn
causes the blades to fly up or down in sequence, depending on the
change in lift."

http://www.car16.info/2007/10/14/motorcycle-rear-wheel-propeller-adapter/
"Many motorcycles can travel up to 165 mph in sixth gear. The average
Cessna private airplane, which has a single-engine takes off at about
40 miles per hour. So why can t a motorcycle fly? Only one reason it
does not have wings and it does not have a propeller."

On Dec 21, 7:56�pm, "gdewi...@gmail.com" <gdewi...@gmail.com> wrote:

> You are of course right but I'm just being curious. Who knows what we
> can come up with.

One never knows where curiousity may lead, but it helps to focus your
search by
getting involved in some kind of project with a goal. Sudent projects
often involve attempts to exploit the essence of some pet theory,
without ever finding out how the
idea translates into reality.

> If it's really worth it we should investigate how to create additional
> drag with the wheel.

Motor vehicle braking technology being quite adequate, I can't imagine
any use for
additional wheel drag due to aerodynamic effects.

> So far I found this patent from Mr Barefoot, not entirely sure how it
> works but the toy makes lift from spin and the patent makes
> interesting citations from sailing and flying machines.http://www.google.com/patents?vid=USPAT4051622

It works like an end-plated airfoil, creating "lift" by a combination
of Bernoulli principle, Newtonian reaction and circulation theory.

> The owner had covered the back seat in aluminum foil (as a joke) but
> the foil was blowing upwards from the tire. He wasn't going that fast
> and there was at least 15 cm of space between the wheel and the
> spontaneously self assembled measurement apparatus. :-)

How do you know that the lift on the aluminum foil wasn't caused by
air under the foil trying to move into the low pressure region behind
the rider's butt?

> I'm just curious :-)

Curiousity is a sign of an active mind.

On Dec 21, 10:56 pm, "gdewi...@gmail.com" <gdewi...@gmail.com> wrote:
> On Dec 22, 2:02 am, Buteo lineatus <Buteo.linea...@gmail.com> wrote:
>
> > On Dec 21, 4:01?pm, "gdewi...@gmail.com" <gdewi...@gmail.com> wrote:
>
> > > Thanks for the references. I confess I don't know much about the
> > > topic.
>
> > I think you should study up on boundary layer, Reynolds numbers,
> > laminar flow, turbulent flow, Coanda effect, and Tesla boundary layer
> > pumps before considering any technological solutions if you're trying
> > to set some kind of record with a bicycle.
>
> You are of course right but I'm just being curious. Who knows what we
> can come up with.
>
>
>
>
>
> > > To me it seems like a simple flexible extension at the front of the
> > > rear wheel cover (like in my illustration) would suffer a downwards
> > > force. As this would tend to bend the extension forwards it should
> > > create some trust.
>
> > Yes, it could create some small amount of thrust, but you have to
> > realize that the dynamic pressure of air = density ratio X mass of air
> > X velocity in ft/sec^2 X cross-sectional area pf the stream
>
> > The mass of air is so low and the velocity of the air pumped by the
> > tire is very low,
> > so the dynamic pressure will be small.
>
> > > The boundary layer flow is already squashed into
> > > the ground, I don't think it can get much worse application as that.
>
> > No, the boundary layer is viscous and stays attached to the rotating
> > tire as long as flow in laminar. The larger stream of air outside the
> > boundary layer would be moving slower than the air stuck in the
> > boundary layer.
>
> I didn't word that correctly. The layer closest to the tire would go
> almost as fast as the tire. The first one is glued onto the tire,
> every next layer goes a bit slower.
>
> I was suggesting to gradually compress the slowest part so that it
> goes faster as the medium flow. In stead of having a solid frame
> around the wheel it would then be sealed in (some what) moving air.
>
> > > By gradually making the circle smaller the air accelerates around the
> > > rim. Like a ballerina pulling her arms in.
>
> > You're thinking of angular momentum, and I doubt if the polar moment
> > of inertia of a mass of air amounts to anything. You can google up
> > "flywheel" at Wikipedia to study that subject.
>
> Only the fastest moving layer should remain on the tire. The slower
> layers create drag on the ground and cross the air flowing around the
> bike.(underneath)
>
> So it would be thrust in exchange for drag.
>
> If it's really worth it we should investigate how to create additional
> drag with the wheel.
>
> So far I found this patent from Mr Barefoot, not entirely sure how it
> works but the toy makes lift from spin and the patent makes
> interesting citations from sailing and flying machines.http://www.google.com/patents?vid=USPAT4051622
>
> > > Would that make the boundary layer drag go faster as the tire?
>
> > > If so, would it create any note-worthy trust?
>
> > I doubt it. The fastest dustbin-faired downhill bicycle I ever saw
> > only went about 130 mph. With 32-inch diameter wheels, the RPM at 130
> > is only 1365 RPM.
>
> > But, if you study Tesla boundary layer pumps you can get some idea of
> > how fast the disks have turn to move an appreciable amount of air.
>
> I started thinking about this when I saw the wind coming from the rear
> wheel of a bicycle riding in front of me.
>
> The owner had covered the back seat in aluminum foil (as a joke) but
> the foil was blowing upwards from the tire. He wasn't going that fast
> and there was at least 15 cm of space between the wheel and the
> spontaneously self assembled measurement apparatus. :-)
>
> As that was just a slow moving bike I became curious how much wind
> motor cycles blow into the ground. The tire isn't quite flat like a
> Tesla turbine.
>
> Still that doesn't mean there is note worthy action to be exploited.
>
> I'm just curious :-)
>
> http://gabydewilde.googlepages.com/wheel-cover-turbine
> gabydewilde - wheel cover turbine- Hide quoted text -
>
> - Show quoted text -

Put an inlet on one side of the wheel in front and an outlet on the
other side of the wheel toward the back. The spoke area of the wheel
should be compleatly enclosed. Make the spokes into blades of a fan.

Notice that on GP bikes and many race replicas they have a close
fitting rear fender attached to the swingarm to maintain the close
spacing.

Bruce

On 2007-12-22, bsr3997@my-deja.com <bsr3997@my-deja.com> wrote:
> On Dec 21, 10:56 pm, "gdewi...@gmail.com" <gdewi...@gmail.com> wrote:
[...]
>> As that was just a slow moving bike I became curious how much wind
>> motor cycles blow into the ground. The tire isn't quite flat like a
>> Tesla turbine.
>>
>> Still that doesn't mean there is note worthy action to be exploited.
>>
>> I'm just curious :-)
>>
>> http://gabydewilde.googlepages.com/wheel-cover-turbine
>> gabydewilde - wheel cover turbine- Hide quoted text -
>>
>> - Show quoted text -
>
> Put an inlet on one side of the wheel in front and an outlet on the
> other side of the wheel toward the back. The spoke area of the wheel
> should be compleatly enclosed.

I cannot rule out the possibility that that kind of thing might have
some beneficial effect.

> Make the spokes into blades of a fan.

But I'm sure this is going too far. If you make the wheel into a fan,
then in effect you're propelling the bike partly by swimming through the
air rather than by pushing against the road. This is certainly going to
be much less efficient.

You could connect the cranks not to the back wheel at all but to a big
propeller on the front or rear. But I would bet dollars to doughnuts
that would be much less efficient than if you did just connect it to the
wheel.

It's one thing to try to improve the overall drag of a vehicle with some
solution involving moving parts-- this is quite an interesting question.
It's quite another to actually increase the work you're doing in
stirring up the air as a means of pushing the vehicle along. I doubt
that's ever going to be as efficient as turning a wheel against a road.

On Dec 22, 2:19�pm, Ben C <spams...@spam.eggs> wrote:

> It's one thing to try to improve the overall drag of a vehicle with some
> solution involving moving parts-- this is quite an interesting question.
> It's quite another to actually increase the work you're doing in
> stirring up the air as a means of pushing the vehicle along. I doubt
> that's ever going to be as efficient as turning a wheel against a road

Using a propellor to drive a land vehicle is a dumb idea.

The aerodynamic thrust that comes off a propellor is sensitive to the
square of the air velocity passing over the blades, so fixed pitch
propellors work best over a narrow speed range and variable pitch
propellors are used for high speed aircraft.

Imagine varying the angle of your wheel spokes to get more thrust to
go faster and the idea gets ridiculous. A wheel is a wheel, it
transmits mechanical power, not aerodynamic thrust.

Gas turbine engines have many blades, while a propeller might have
from 2 to 5 blades. Gas turbines produce so little power at lower RPM,
80% throtlle is idle speed.

On Dec 22, 10:22 am, Buteo lineatus <Buteo.linea...@gmail.com> wrote:
> On Dec 21, 7:56�pm, "gdewi...@gmail.com" <gdewi...@gmail.com> wrote:
>
> > You are of course right but I'm just being curious. Who knows what we
> > can come up with.
>
> One never knows where curiousity may lead, but it helps to focus your
> search by
> getting involved in some kind of project with a goal. Sudent projects
> often involve attempts to exploit the essence of some pet theory,
> without ever finding out how the
> idea translates into reality.
>
> > If it's really worth it we should investigate how to create additional
> > drag with the wheel.
>
> Motor vehicle braking technology being quite adequate, I can't imagine
> any use for
> additional wheel drag due to aerodynamic effects.
>
> > So far I found this patent from Mr Barefoot, not entirely sure how it
> > works but the toy makes lift from spin and the patent makes
> > interesting citations from sailing and flying machines.http://www.google..com/patents?vid=USPAT4051622
>
> It works like an end-plated airfoil, creating "lift" by a combination
> of Bernoulli principle, Newtonian reaction and circulation theory.
>
> > The owner had covered the back seat in aluminum foil (as a joke) but
> > the foil was blowing upwards from the tire. He wasn't going that fast
> > and there was at least 15 cm of space between the wheel and the
> > spontaneously self assembled measurement apparatus. :-)
>
> How do you know that the lift on the aluminum foil wasn't caused by
> air under the foil trying to move into the low pressure region behind
> the rider's butt?
>
> > I'm just curious :-)
>
> Curiousity is a sign of an active mind.

ALL HAIL STEVE FOSSETT

On Dec 22, 4:22 pm, Buteo lineatus <Buteo.linea...@gmail.com> wrote:
> How do you know that the lift on the aluminum foil wasn't caused by
> air under the foil trying to move into the low pressure region behind
> the rider's butt?
>

Yes, but of course, that has to be it. The pressure is there but that
vacuum is obviously much bigger. To move air we need both a high and a
low pressure zone. So my weird observation was that air flows from the
back end of the tire to the back of the rider. It's still weird to
see.


> Motor vehicle braking technology being quite adequate, I can't imagine
> any use for additional wheel drag due to aerodynamic effects.
>

Yeah, but I'm sure you can imagine creating drag is possible. Just
treat it like an ability to create something. Drag doesn't sound very
useful but it's work to move air? Have to use the tire because there
isn't any room on a bike for devices that size.

> > So far I found this patent from Mr Barefoot, not entirely sure how it
> > works but the toy makes lift from spin and the patent makes
> > interesting citations from sailing and flying machines.http://www.google.com/patents?vid=USPAT4051622
>
> It works like an end-plated airfoil, creating "lift" by a combination
> of Bernoulli principle, Newtonian reaction and circulation theory.
>

Even tho it sounds impossible I was trying to figure out how to fit
the wheel into the rim under an angle. We have flexible couplings, it
should be possible to have the rim move under a different angle from
the rest of the wheel and put blades on the spokes so that the drag
accelerates the wheel as if sailing up the wind.

I put a new turbine design on the page. Nothing has the right size,
it's just an illustration of a thought.

http://gabydewilde.googlepages.com/wheel-cover-turbine
gabydewilde - wheel cover turbine

I was drawing to slow it was already described by Bruce in the
meantime.

On Dec 22, 10:07 pm, "bsr3...@my-deja.com" <bsr3...@my-deja.com>
wrote:
> On Dec 21, 10:56 pm, "gdewi...@gmail.com" <gdewi...@gmail.com> wrote:
>
>
>
> > On Dec 22, 2:02 am, Buteo lineatus <Buteo.linea...@gmail.com> wrote:
>
> > > On Dec 21, 4:01?pm, "gdewi...@gmail.com" <gdewi...@gmail.com> wrote:
>
> > > > Thanks for the references. I confess I don't know much about the
> > > > topic.
>
> > > I think you should study up on boundary layer, Reynolds numbers,
> > > laminar flow, turbulent flow, Coanda effect, and Tesla boundary layer
> > > pumps before considering any technological solutions if you're trying
> > > to set some kind of record with a bicycle.
>
> > You are of course right but I'm just being curious. Who knows what we
> > can come up with.
>
> > > > To me it seems like a simple flexible extension at the front of the
> > > > rear wheel cover (like in my illustration) would suffer a downwards
> > > > force. As this would tend to bend the extension forwards it should
> > > > create some trust.
>
> > > Yes, it could create some small amount of thrust, but you have to
> > > realize that the dynamic pressure of air = density ratio X mass of air
> > > X velocity in ft/sec^2 X cross-sectional area pf the stream
>
> > > The mass of air is so low and the velocity of the air pumped by the
> > > tire is very low,
> > > so the dynamic pressure will be small.
>
> > > > The boundary layer flow is already squashed into
> > > > the ground, I don't think it can get much worse application as that.
>
> > > No, the boundary layer is viscous and stays attached to the rotating
> > > tire as long as flow in laminar. The larger stream of air outside the
> > > boundary layer would be moving slower than the air stuck in the
> > > boundary layer.
>
> > I didn't word that correctly. The layer closest to the tire would go
> > almost as fast as the tire. The first one is glued onto the tire,
> > every next layer goes a bit slower.
>
> > I was suggesting to gradually compress the slowest part so that it
> > goes faster as the medium flow. In stead of having a solid frame
> > around the wheel it would then be sealed in (some what) moving air.
>
> > > > By gradually making the circle smaller the air accelerates around the
> > > > rim. Like a ballerina pulling her arms in.
>
> > > You're thinking of angular momentum, and I doubt if the polar moment
> > > of inertia of a mass of air amounts to anything. You can google up
> > > "flywheel" at Wikipedia to study that subject.
>
> > Only the fastest moving layer should remain on the tire. The slower
> > layers create drag on the ground and cross the air flowing around the
> > bike.(underneath)
>
> > So it would be thrust in exchange for drag.
>
> > If it's really worth it we should investigate how to create additional
> > drag with the wheel.
>
> > So far I found this patent from Mr Barefoot, not entirely sure how it
> > works but the toy makes lift from spin and the patent makes
> > interesting citations from sailing and flying machines.http://www.google.com/patents?vid=USPAT4051622
>
> > > > Would that make the boundary layer drag go faster as the tire?
>
> > > > If so, would it create any note-worthy trust?
>
> > > I doubt it. The fastest dustbin-faired downhill bicycle I ever saw
> > > only went about 130 mph. With 32-inch diameter wheels, the RPM at 130
> > > is only 1365 RPM.
>
> > > But, if you study Tesla boundary layer pumps you can get some idea of
> > > how fast the disks have turn to move an appreciable amount of air.
>
> > I started thinking about this when I saw the wind coming from the rear
> > wheel of a bicycle riding in front of me.
>
> > The owner had covered the back seat in aluminum foil (as a joke) but
> > the foil was blowing upwards from the tire. He wasn't going that fast
> > and there was at least 15 cm of space between the wheel and the
> > spontaneously self assembled measurement apparatus. :-)
>
> > As that was just a slow moving bike I became curious how much wind
> > motor cycles blow into the ground. The tire isn't quite flat like a
> > Tesla turbine.
>
> > Still that doesn't mean there is note worthy action to be exploited.
>
> > I'm just curious :-)
>
> >http://gabydewilde.googlepages.com/wheel-cover-turbine
> > gabydewilde - wheel cover turbine- Hide quoted text -
>
> > - Show quoted text -
>
> Put an inlet on one side of the wheel in front and an outlet on the
> other side of the wheel toward the back. The spoke area of the wheel
> should be compleatly enclosed. Make the spokes into blades of a fan.
>
> Notice that on GP bikes and many race replicas they have a close
> fitting rear fender attached to the swingarm to maintain the close
> spacing.
>
> Bruce

I was thinking of just that, thanks for pointing out the GP bikes.

My drawing of what you describe is on the page.

http://gabydewilde.googlepages.com/wheel-cover-turbine
gabydewilde - wheel cover turbine

On Dec 22, 11:19 pm, Ben C <spams...@spam.eggs> wrote:
> On 2007-12-22, bsr3...@my-deja.com <bsr3...@my-deja.com> wrote:
>
>
>
> > On Dec 21, 10:56 pm, "gdewi...@gmail.com" <gdewi...@gmail.com> wrote:
> [...]
> >> As that was just a slow moving bike I became curious how much wind
> >> motor cycles blow into the ground. The tire isn't quite flat like a
> >> Tesla turbine.
>
> >> Still that doesn't mean there is note worthy action to be exploited.
>
> >> I'm just curious :-)
>
> >>http://gabydewilde.googlepages.com/wheel-cover-turbine
> >> gabydewilde - wheel cover turbine- Hide quoted text -
>
> >> - Show quoted text -
>
> > Put an inlet on one side of the wheel in front and an outlet on the
> > other side of the wheel toward the back. The spoke area of the wheel
> > should be compleatly enclosed.
>
> I cannot rule out the possibility that that kind of thing might have
> some beneficial effect.
>
> > Make the spokes into blades of a fan.
>
> But I'm sure this is going too far. If you make the wheel into a fan,
> then in effect you're propelling the bike partly by swimming through the
> air rather than by pushing against the road. This is certainly going to
> be much less efficient.
>

Imagine each blade as a sail sailing close to the wind. If the blade
is not spinning forwards the "wind" from the drag is not coming from
the direction the blade is traveling in.

Even tho it sounds impossible I was trying to figure out how to fit
the wheel into the rim under an angle. We have flexible couplings, it
should be possible to have the rim move under a different angle from
the rest of the wheel.

But it would still require blade shaped spokes so it would be easier
to change the wind direction in the first place.

> You could connect the cranks not to the back wheel at all but to a big
> propeller on the front or rear. But I would bet dollars to doughnuts
> that would be much less efficient than if you did just connect it to the
> wheel.
>
> It's one thing to try to improve the overall drag of a vehicle with some
> solution involving moving parts-- this is quite an interesting question.
> It's quite another to actually increase the work you're doing in
> stirring up the air as a means of pushing the vehicle along. I doubt
> that's ever going to be as efficient as turning a wheel against a road.

Yes, more parts = bad need to use the same parts for everything and
even eliminate them where we can. This makes the wheel an interesting
candidate to become a propeller.

Drag is mainly caused by frontal surface area if we put the wheel
inlet at the front it would remove the drag from that surface and put
a vacuum there.

It all sounds a bit Battle star galactica but that is from 1980

600 internet years ago.

hehehe

http://gabydewilde.googlepages.com/wheel-cover-turbine
gabydewilde - wheel cover turbine

On Dec 21, 5:20 pm, Buteo lineatus <Buteo.linea...@gmail.com> wrote:
> On Dec 21, 12:29�pm, "gdewi...@gmail.com" <gdewi...@gmail.com> wrote:
>
> > A tire drags air along it's rim, this airstream becomes thicker and
> > more violent when you go faster. I was thinking perhaps it is possible
> > to find a way to cut this Mohawk of air into a more useful shape.
>
> The air pumping effect is at its worst with slick tires because of the
> boundary layer.
>
> Tread patterns will break up the boundary layer and cause turbulent
> flow.
>
> Another way to break up the boundary layer is by using a strategically
> positioned
> "trip wire" such as model airplane pylon racers employ.
>
> Sportsracing cars using treadless tires will have louvers in the tops
> of the fenders to reduce drag caused by the tires acting as air pumps.

tires pump air? is this why disc brakes come with heater elements for
those long straights?