Metalworking (rec.crafts.metalworking) Discuss various aspects of working with metal, such as machining, welding, metal joining, screwing, casting, hardening/tempering, blacksmithing/forging, spinning and hammer work, sheet metal work.

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  #21   Report Post  
Old March 18th 08, 04:02 PM posted to rec.crafts.metalworking
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Default New electrical generator

On Tue, 18 Mar 2008 05:25:23 GMT, "Leo Lichtman"
wrote:
"Ed Huntress" wrote:


Efficiency of large power-plant generators runs
around 98%, shaft input power to electrical output.

^^^^^^^^^^^^^^^^^^
Do you have any kind of ballpark figure of the efficiency of the
distributionn grid, from the generator terminals to the average consumer? I
would like to know this, because when people talk about the cleanliness of
electric cars, they frequently forget that there is CO2 coming out the
stacks at the power plant. Steam generation plants run MUCH cleaner than
automotive IC engines, but how much of that advantage do we lose in the
grid?


I've seen figures thrown around in the 40% to 50% range to get the
energy from the burning coal or oil or gas in the powerplant to your
wall socket. The generator at the power plant might be 98% by itself
(2% loss), but the prime mover is a huge loss. The excess heat going
up the stack and out the cooling towers, and all the little motors and
fans keeping the big motor running that do all the pumping and blowing
and cooling and lubricating and stack filtering...

Then you have the transmission lines, with little bits siphoned off
in resistive loss and flash-over of insulators and dielectric losses
in underground cables. And every transformer along the way taking a
small bite, whether it's stepping voltage up or down.

A nibble here, a bite there, and suddenly it's half gone.

The only real exception is hydroelectric, wind turbines, geothermal,
and the like. There are still losses, but gravity and wind and magma
are free (in limited quantities). And building the facilities to
exploit them safely (Hoover Dam) costs quite a bit, and has to be
figured into the 'cost' of that power.

(Versus the cost of exploiting them *un*safely - St. Francis Dam,
Saugus CA, built 1926 failed 1928, killed thousands when it did...)

This is why when you need bulk heat for hot water or cooking or
space heat, you buy the fuel (coal, oil, propane, natural gas, wood)
and burn it yourself on site. You have to deal with the equipment,
sure, but you also cut out that 50% loss middleman that is always
involved with electric heat.

-- Bruce --

  #22   Report Post  
Old March 18th 08, 06:51 PM posted to rec.crafts.metalworking
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Default New electrical generator


"Bruce L. Bergman" wrote in message
...
On Tue, 18 Mar 2008 05:25:23 GMT, "Leo Lichtman"
wrote:
"Ed Huntress" wrote:


Efficiency of large power-plant generators runs
around 98%, shaft input power to electrical output.

^^^^^^^^^^^^^^^^^^
Do you have any kind of ballpark figure of the efficiency of the
distributionn grid, from the generator terminals to the average consumer?
I
would like to know this, because when people talk about the cleanliness of
electric cars, they frequently forget that there is CO2 coming out the
stacks at the power plant. Steam generation plants run MUCH cleaner than
automotive IC engines, but how much of that advantage do we lose in the
grid?


I've seen figures thrown around in the 40% to 50% range to get the
energy from the burning coal or oil or gas in the powerplant to your
wall socket. The generator at the power plant might be 98% by itself
(2% loss), but the prime mover is a huge loss.


The simplex prime movers, steam or gas turbine, typically run from 37% up to
45% or so efficiency. The newer, "combined cycle" turbines run around 56% -
58%. GE has one that has topped 60%. These are gas turbines that use the
turbine's exhaust to heat a steam boiler, then a steam turbine operating as
the second stage.

So the overall efficiency of these systems run around 0.98 x 0.56, or 55%.
Slightly higher is possible. I see that Wikipedia claims that the overall US
distribution/transmission efficiency, as of 1995, was 92.8% (they report it
as a loss of 7.2%).

(BTW, on a related topic, a solar Stirling at Sandia (I think) just topped
31% efficiency, which is a new record. That's twice the efficiency of the
best photovoltaic cells.)

--
Ed Huntress


  #23   Report Post  
Old March 18th 08, 09:13 PM posted to rec.crafts.metalworking
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Posts: 48
Default New electrical generator

On Mar 17, 11:14*am, "Phil Kangas" wrote:
Yah, this guy claims to have invented a new form of
generator and claims it is not a perpetual motion
device! I'm a skeptic but here is the link so you
can decide for yourself. I'm going to keep my wallet
in my pocket......phil

http://www.nullgrav.com/index.htm

--
The right of the people to keep and bear
arms shall not be infringed.


This looks to be a variation of the Farady Disk generator.
This was discovered, and promptly ignored, about 150 years ago.

It is a very strange phenomenon, and easy to really get tangled up in
the implications of it.

Basically, all common generators, and motors, use a rotor and a
stator. The electrical load currents will create an opposing magnetic
force between the rotor and the stator.
That is why a genreator takes more power as you load it heavier.

The Farady Disk, aka homopolar generator, aka acyclical generator, aka
space machine etc. does not have a rotor, and a stator. Only a rotor.
That's right, only a rotor. The whole things works "sideways" to how
you always thought a generator should work.
It is Very confusing to think about, since adding a load to the
generator cannot create a torque reaction in the conventional way we
all understand generators to work. Note 1.

So, many experimentors start thinking, that if we build it, and spin
it up, we can add a load to it, and it won't take power to keep it
spinning, since it won't react against the motor driving it.

Experiments show anomolous results, and building a model to play with
is truely trivial.
I challenge any of you to build a model to prove that it IS confusing
to think about.

Here is a simple experiment to try..
http://jnaudin.free.fr/html/farhom.htm



Here is a test result of the Sunburst Machine.

http://www.rexresearch.com/kinchelo/kinche~1.htm

This nullgrav machine looks very much like a variation of the Farady
disk experiment.


And to illustrate just how confusing this sort of thing can be...
Here is a lab demonstration from MIT, that WILL blow your mind, if
you follow it, and all of it's implication. It blows Kirchoff right
out of the water. ..

http://youtube.com/watch?v=eqjl-qRy71w

Watch both parts of this demo. Prof. Levin is really amazing.... Look
for the rest of his lectures.

Have Fun. !!

Note 1.
The operation of the device can lead you to believe that a magnet
cannot "produce" a magnetic field, but can only distort the magnetic
field lines inherent on space itself.
If a magnet did produced a magnetic field, than rotating a magnet, and
a conductor together could not produce any net electrical generation.
However, if the magnet is distorting the feild lines of the
surrounding space, then a moving conductor (which is not moving
relative to the magnet) can produce an electric field.


I don't beleive in "Perpetual Commotion" But, here is a wonderful trap
for the unwary to fall in to, and in all honesty be completley
befuddled.
Be sure and wathc the MIT video. It's is one of the greatest
electrical demonstrations I've ever seen.
  #24   Report Post  
Old March 19th 08, 03:28 AM posted to rec.crafts.metalworking
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Posts: 19
Default New electrical generator


"Half-Nutz" wrote in messageOn Mar 17, 11:14 am,
"Phil Kangas" wrote:
Yah, this guy claims to have invented a new form of
generator and claims it is not a perpetual motion
device! I'm a skeptic but here is the link so you
can decide for yourself. I'm going to keep my wallet
in my pocket......phil

http://www.nullgrav.com/index.htm

--
The right of the people to keep and bear
arms shall not be infringed.


This looks to be a variation of the Farady Disk generator.
This was discovered, and promptly ignored, about 150 years
ago.

It is a very strange phenomenon, and easy to really get
tangled up in
the implications of it.

Basically, all common generators, and motors, use a rotor
and a
stator. The electrical load currents will create an opposing
magnetic
force between the rotor and the stator.
That is why a genreator takes more power as you load it
heavier.

The Farady Disk, aka homopolar generator, aka acyclical
generator, aka
space machine etc. does not have a rotor, and a stator. Only
a rotor.
That's right, only a rotor. The whole things works
"sideways" to how
you always thought a generator should work.
It is Very confusing to think about, since adding a load to
the
generator cannot create a torque reaction in the
conventional way we
all understand generators to work. Note 1.

So, many experimentors start thinking, that if we build it,
and spin
it up, we can add a load to it, and it won't take power to
keep it
spinning, since it won't react against the motor driving it.

Experiments show anomolous results, and building a model to
play with
is truely trivial.
I challenge any of you to build a model to prove that it IS
confusing
to think about.

Here is a simple experiment to try..
http://jnaudin.free.fr/html/farhom.htm



Here is a test result of the Sunburst Machine.

http://www.rexresearch.com/kinchelo/kinche~1.htm

This nullgrav machine looks very much like a variation of
the Farady
disk experiment.


And to illustrate just how confusing this sort of thing can
be...
Here is a lab demonstration from MIT, that WILL blow your
mind, if
you follow it, and all of it's implication. It blows
Kirchoff right
out of the water. ..

http://youtube.com/watch?v=eqjl-qRy71w

Watch both parts of this demo. Prof. Levin is really
amazing.... Look
for the rest of his lectures.

Have Fun. !!

Note 1.
The operation of the device can lead you to believe that a
magnet
cannot "produce" a magnetic field, but can only distort the
magnetic
field lines inherent on space itself.
If a magnet did produced a magnetic field, than rotating a
magnet, and
a conductor together could not produce any net electrical
generation.
However, if the magnet is distorting the feild lines of the
surrounding space, then a moving conductor (which is not
moving
relative to the magnet) can produce an electric field.


I don't beleive in "Perpetual Commotion" But, here is a
wonderful trap
for the unwary to fall in to, and in all honesty be
completley
befuddled.
Be sure and wathc the MIT video. It's is one of the greatest
electrical demonstrations I've ever seen.

--------------------------

Thanks for the explanation, half-nutz. I'll bet the dude in
question fell
into that trap........and we learned something too!
phil


  #25   Report Post  
Old March 19th 08, 09:25 PM posted to rec.crafts.metalworking
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First recorded activity by DIYBanter: Aug 2007
Posts: 48
Default New electrical generator

On Mar 18, 10:28*pm, "Phil Kangas" wrote:
"Half-Nutz" wrote in messageOn Mar 17, 11:14 am,

*"Phil Kangas" wrote:

Yah, this guy claims to have invented a new form of
generator and claims it is not a perpetual motion
device! I'm a skeptic but here is the link so you
can decide for yourself. I'm going to keep my wallet
in my pocket......phil


http://www.nullgrav.com/index.htm


--
The right of the people to keep and bear
arms shall not be infringed.


This looks to be a variation of the Farady Disk generator.
This was discovered, and promptly ignored, about 150 years
ago.

It is a very strange phenomenon, and easy to really get
tangled up in
the implications of it.

Basically, all common generators, and motors, use a rotor
and a
stator. The electrical load currents will create an opposing
magnetic
force between the rotor and the stator.
That is why a genreator takes more power as you load it
heavier.

The Farady Disk, aka homopolar generator, aka acyclical
generator, aka
space machine etc. does not have a rotor, and a stator. Only
a rotor.
That's right, only a rotor. The whole things works
"sideways" to how
you always thought a generator should work.
It is Very confusing to think about, since adding a load to
the
generator cannot create a torque reaction in the
conventional way we
all understand generators to work. Note 1.

So, many experimentors start thinking, that if we build it,
and spin
it up, we can add a load to it, and it won't take power to
keep it
spinning, since it won't react against the motor driving it.

Experiments show anomolous results, and building a model to
play with
is truely trivial.
I challenge any of you to build a model to prove that it IS
confusing
to think about.

Here is a simple experiment to try..http://jnaudin.free.fr/html/farhom.htm

Here is a test result of the Sunburst Machine.

http://www.rexresearch.com/kinchelo/kinche~1.htm

This nullgrav machine looks very much like a variation of
the Farady
disk experiment.

And to illustrate just how confusing this sort of thing can
be...
Here is a lab demonstration from MIT, that *WILL blow your
mind, if
you follow it, and all of it's implication. It blows
Kirchoff right
out of the water. ..

http://youtube.com/watch?v=eqjl-qRy71w

Watch both parts of this demo. Prof. Levin is really
amazing.... Look
for the rest of his lectures.

Have Fun. !!

Note 1.
The operation of the device can lead you to believe that a
magnet
cannot "produce" a magnetic field, but can only distort the
magnetic
field lines inherent on space itself.
If a magnet did produced a magnetic field, than rotating a
magnet, and
a conductor together could not produce any net electrical
generation.
However, if the magnet is distorting the feild lines of the
surrounding space, then a moving conductor (which is not
moving
relative to the magnet) can produce an electric field.

I don't beleive in "Perpetual Commotion" But, here is a
wonderful trap
for the unwary to fall in to, and in all honesty be
completley
befuddled.
Be sure and wathc the MIT video. It's is one of the greatest
electrical demonstrations I've ever seen.

--------------------------

Thanks for the explanation, half-nutz. I'll bet the dude in
question fell
into that trap........and we learned something too!
phil


Phil,

It is not clear what is going on with that type of device.
The evaluation of the Sunburst machine did have some faily confusing
results, as to weather or not they were measuring excessive power
compared to the input.

- IF - this is some sort of way to harness some sort of overlooked
source of energy, then the controversy surrounding it keeps anybody
from looking into it, and not getting thrown out of the mainstream
community.
Bruce DePalma was a prof. at MIT, and left after he got controversial
results from his experiments with gyroscopes.
Eric Laithwaite, who invented the Maglev train, was thown out of the
scientific community once he started doing experiments on gyroscopes,
along a similar line.

I once met the machinist that built the machine for Bruce DePalma. He
was Convinced that Bruce was killed for working on it.

This whole line of experiments might yield some interesting results,
but since the results are "anomolous" to mainstream thinking, no one
dares to look into it.


I am reminded of the Hall effect, Hall himself dismised it as being of
no interest, since the effect was so weak. And here we are, many years
later, using millions of Hall Effect switches and sensors.
The enabler to utilize what seemed like a discovery of little
consequence, was the later invention of electronic op amps, many years
later.
So, sometimes we get important results from something that mainstream
thinking will throw away. It is not always immediately usefull, but
any crazy phenomonon should be looked into a little farther,
typically.


So, this controversial "sideways" motor/generator might be revealing
something very important to us, but no one dares to look into it.
A shame, really.


  #26   Report Post  
Old March 20th 08, 12:31 AM posted to rec.crafts.metalworking
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First recorded activity by DIYBanter: Apr 2007
Posts: 3,138
Default New electrical generator

On Tue, 18 Mar 2008 14:13:13 -0700 (PDT), Half-Nutz
wrote:

On Mar 17, 11:14*am, "Phil Kangas" wrote:
Yah, this guy claims to have invented a new form of
generator and claims it is not a perpetual motion
device! I'm a skeptic but here is the link so you
can decide for yourself. I'm going to keep my wallet
in my pocket......phil

http://www.nullgrav.com/index.htm

--
The right of the people to keep and bear
arms shall not be infringed.


This looks to be a variation of the Farady Disk generator.
This was discovered, and promptly ignored, about 150 years ago.

It is a very strange phenomenon, and easy to really get tangled up in
the implications of it.

Basically, all common generators, and motors, use a rotor and a
stator. The electrical load currents will create an opposing magnetic
force between the rotor and the stator.
That is why a genreator takes more power as you load it heavier.

The Farady Disk, aka homopolar generator, aka acyclical generator, aka
space machine etc. does not have a rotor, and a stator. Only a rotor.
That's right, only a rotor. The whole things works "sideways" to how
you always thought a generator should work.
It is Very confusing to think about, since adding a load to the
generator cannot create a torque reaction in the conventional way we
all understand generators to work. Note 1.


I won't presume to know how we all "conventionally understand"
generators to work... but if you examine Faraday's sketch
thoughtfully, you will see that radial current in the disc (in the
presence of the axial B-field) will indeed produce countertorque, and
an opposite torque will act upon the radial lead to the center. The
confusion arises because these torques are so small compared to the
residual losses in such systems that they are easily overlooked.

In the Sunburst experiment, residual losses were relatively enormous
when the thing was generating no power at all, and losses did increase
when power was drawn.
  #27   Report Post  
Old March 20th 08, 12:40 AM posted to rec.crafts.metalworking
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First recorded activity by DIYBanter: Apr 2007
Posts: 3,138
Default New electrical generator

On Tue, 18 Mar 2008 14:13:13 -0700 (PDT), Half-Nutz
wrote:




And to illustrate just how confusing this sort of thing can be...
Here is a lab demonstration from MIT, that WILL blow your mind, if
you follow it, and all of it's implication. It blows Kirchoff right
out of the water. ..

http://youtube.com/watch?v=eqjl-qRy71w

Watch both parts of this demo. Prof. Levin is really amazing.... Look
for the rest of his lectures.


This guy is more performer than docent. Kirchoff's law does not
presume lumped sources of EMF, it states merely that EMF's and drops
in a closed circuit or mesh sum to zero.

It is true that many engineering texts present circuits (and
Kirchoff's law) with lumped EMFs, because in real circuits that is
most often the dominant case.

At one point in his lecture he leads (or at least allows with a bit of
nudge) his "audience" to think that the induced EMF should be thought
of as being lumped at the location where the battery was, which of
course is false. Later he shows a line integral suggesting that the
EMF is indeed distributed, but he still prefers to discredit Kirchoff
in favor of Faraday. The line integral of induced EMF around the
circuit or mesh would and does indeed equal the former battery EMF.

He may be a great mentor for academists, perhaps not for engineers.
  #28   Report Post  
Old March 20th 08, 03:06 AM posted to rec.crafts.metalworking
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Posts: 3,138
Default New electrical generator

On Tue, 18 Mar 2008 22:28:04 -0500, "Phil Kangas"
wrote:


So, many experimentors start thinking, that if we build it,
and spin
it up, we can add a load to it, and it won't take power to
keep it
spinning, since it won't react against the motor driving it.

Experiments show anomolous results, and building a model to
play with
is truely trivial.
I challenge any of you to build a model to prove that it IS
confusing
to think about.

Here is a simple experiment to try..
http://jnaudin.free.fr/html/farhom.htm


The cited experiment sez it generates 0.5 volts, 1.5 mA or 0.75 mW at
2600 RPM. This power level at this speed represents a torque of about
..0004 ozf-in (.00275 Newton-mm to y'all unit purists) regardless of
how the current was generated. It ain't zero, but it's easy to see
why an observer might think so. Compared to countertorque due to
parasitic losses like windage, bearing losses and brush drag it's a
fleafart at a rock concert.

I suggest the following modification to the experiment:

Rather than continuously powering rotation with an electric drill, use
a flywheel. With brushes in place but external wires disconnected,
spin up the flywheel (perhaps with a tangential air jet), then
release it and note the time it takes to slow to a given rate as
measured with a photo tachometer. Could use a hole in the disc, LED
and photosensor from surplus store or discarded mouse and oscilloscope
-- or perhaps just a pattern of radial lines on the disc viewed with
fluorescent or neon light and watch for the "strobe stop".
Now repeat the experiment with external leads connected.

Parasitic losses are the same in both cases if both experiments start
at the same speed.

If the flywheel slows more quickly when the external leads are
connected, there is clearly countertorque due to the rather small
generated current.

  #29   Report Post  
Old March 20th 08, 04:23 AM posted to rec.crafts.metalworking
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Posts: 3,138
Default New electrical generator

On Tue, 18 Mar 2008 22:28:04 -0500, "Phil Kangas"
wrote:


This nullgrav machine looks very much like a variation of
the Farady
disk experiment.


I don't think it does. The Faraday disc experiment has constant flux
while the nullgrav device uses commutated flux reversals thru coils.
It is functionally very similar to an automotive alternator. The
geometry is different, but they both rely on flux commutation to make
an essentially-constant MMF (magnetomotive force) produce
time-variant flux linking fixed coils.
  #30   Report Post  
Old March 20th 08, 07:36 AM posted to rec.crafts.metalworking
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Posts: 3,138
Default New electrical generator

On Tue, 18 Mar 2008 22:28:04 -0500, "Phil Kangas"
wrote:


"Half-Nutz" wrote in messageOn Mar 17, 11:14 am,
"Phil Kangas" wrote:
Yah, this guy claims to have invented a new form of
generator and claims it is not a perpetual motion
device! I'm a skeptic but here is the link so you
can decide for yourself. I'm going to keep my wallet
in my pocket......phil

http://www.nullgrav.com/index.htm

--
The right of the people to keep and bear
arms shall not be infringed.


This looks to be a variation of the Farady Disk generator.
This was discovered, and promptly ignored, about 150 years
ago.


If opportunity presents, I highly recommend a visit to Faraday's
laboratory in London. It's in the basement of a building near the
A&E, British Science Museum and others. Same tube stop.

This guy was a no-**** researcher and an artful artificer as well, no
doubt with the help of a skilled technician who is now forgotten but
shouldn't be. The discoveries he made are most impressive when one
sees what he had to work with and what he was able to do with it.


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