At 04:37 PM 12/30/2009, Stephen A. Lawrence wrote:
On 12/30/2009 03:31 PM, Abd ul-Rahman Lomax wrote:
> At 12:14 PM 12/30/2009, Craig Haynie wrote:
>> Here are two more replications:
>
>> The first link shows no apparent current increase as the speed of the
>> rotor picks up, and tends to really display the effect that is
>> perplexing all of these people.
>>
>> http://www.youtube.com/user/m1a9r9s9#p/u/2/nDABKqdB538
>
> Rather, the key to the effect is the transitions. It is the switching
> of the response of the toroid to the permanent magnets that produces
> the acceleration of the rotor. Steady-state on, the rotor is
> freewheeling. Constant current, independent of rotor speed.
> Steady-state off, likewise, no effect on current (zero) from rotor speed.
Wait -- after reading your descriptions (and others), if I understand
what the descriptions describe, it looks like the "key" is somewhere else.
Depends on key to "what." But sure, I like Mr. Lawrence's
explanation, in some ways. But I'm not sure it's accurate yet.
Look at what we've got: We have a magnetic core in a coil, and a
separate movable magnet, which can move past the core/coil combination.
Ferrite core. (I'm very weak in this field, something whacked me over
the head when the right-hand rule was introduced. Right hand? Why
right hand? Does the universe have something against lefties?
Apparently!) Characteristic of ferrites: the magnetic field can be
easily reversed with relatively low energy losses as heat.
Switch the coil on, the field of the core is canceled. A while later,
switch it off, the field in the core comes back.
Right.
You put energy in when
you switch it on, you get it back when you switch it off; to the extent
that the system gets warm in between you get back less than you put in.
Yes, the back-EMF represents getting the energy back as the magnetic
field collapses. Collapse it quickly, the voltage can go very high,
burning out the switches, unless you dump enough current that the
voltage doesn't rise that high.
However, note, it only takes a certain amount of current to establish
the toriod magnetic field that cancels the ferrite's field. Only that
energy, stored in setting up the toroid field, is returned when
shutting the thing off. The current, however, must be continuous
during the freewheeling phase, or else the ferrite will retard the
rotation of the rotor, by attracting the permanent magnet in the
reverse direction, slowing the rotor down.
That energy is not going to be recovered, it does not get stored in
the rotation, it is pure heat loss.
Fine, but that's not where the "motor" part comes in. The "motor" part
is the interaction between the "other" magnet and the coil. The full
system is apparently this:
1) A magnet moves close to the magnetic core. It's attracted to the
core, so it gains mechanical energy during this phase.
Yes. Now, without the switching system, the rotor will oscillate if
it starts out with the magnet to one side of the ferrite. This will
continue and slow down only due to friction, because whatever is
gained in one direction is exactly subtracted in the reverse direction.
2) At closest approach, the coil turns on, energy goes into the system,
and the core is quenched.
Yes.
3) The magnet moves away from the core AND coil. Since the field of the
core is canceled, this apparently takes no work.
And it doesn't take work. That is, at that point, the rotor is freewheeling.
But notice, the core has a certain field. That field could be
reproduced by an electromagnet. In this configuration, the permanent
magnet on the rotor would be attracted by the electromagnet, which,
when the permanent magnet passes it, would be shut off, awaiting the
next cycle of approach. In this situation, we have one kind of motor.
We are attracting a part of the rotor with an electromagnet, it takes
energy to set up that attraction, which then does the work.
The Steorn motor appears to be symmetrically the reverse. Instead of
the work being done when the coil is energized, it's done when the
coil is de-energized.
But, it seems, or we would expect, the energy is the same either way,
it's simply that the arrangement operates inversely. It appears that
Steorn claims some anomaly in this. *How much of an anomaly?* If the
anomaly is near noise levels, difficult to measure, compared to the
energy already being dumped into the system, we can easily consider
it artifact.
However, Steorn is claiming 300%. I.e., that for every watt-second
going into the coil, there are two watt-seconds of power going into
the rotational energy of the rotor. This, if true, would not be
marginal. But it would then also be easy to recover that energy and
use it to maintain or increase the battery charge (or, much nicer, a
supercapacitor charge, which then would provide a very convenient and
direct measure of energy storage, not complicated). The generator
would have to be only 50% efficient at converting rotary energy to
charge. My sense is that this is quite doable, anyone know better? (I
expect quite a few readers here will know the engineering much better than I).
4) At maximum separation the coil is turned off.
Or something like that.
The only interaction between a live electrical circuit and a physical
object on which it can do work is in step (3). In that step, the coil
is energized in such a way that it would REPEL the magnet, which is
moving away from it.
Well, *the combination* doesn't repel, but, yes, you can think of the
coil as repelling while the core is attracting, and the repulsion and
attraction cancel each other out. I'm not at all certain of this
description, though, because I'm not clear on the special qualities
of ferrites.
Think about it -- the core attracts the other
magnet, and the coil is canceling that attraction, so the coil is
repelling the other magnet. In essence, the coil is pushing the magnet
away, working against the attractive force of the coil.
against the attractive force of the core that would otherwise exist.
And that effectively repulsive force must be maintained continuously
during this phase. Whereas if we were operating in the reverse mode,
attracting the permanent magnet with an electromagnet, we'd be doing
work directly instead of indirectly. Looks symmetrical to me.
Suppose I have a magnet on a rotor. I hold another magnet on my hand,
and move it with the same pole toward the magnet rotor, repelling it.
This takes work. Similar work is involved if I set up a magnetic
field to do the same thing in an electromagnet. Then, when my held
magnet would be in position to retard the permanent magnet coming
around on the rotor, I pull it back, and only replace it when the
position is such that it will again repel.
My work is done by my moving the magnet, against a repulsive field
(plus work done to move the magnet back and forth, which simply
dissipates heat). The same work is done if I don't move the magnet
but instead energize an electromagnet at the appropriate times.
If we could find a way to move the held magnet back and forth without
doing work, we'd have a perpetual motion machine. Steorn has found a
trick that *looks like* we aren't doing any work on the rotor, and we
are merely expending what is considered to be "a little" work on
setting up and shutting down a magnetic field. It turns out to be a
lot of work, actually, which is why the batteries run down as quickly
as they do. It would be much more efficient, I suspect, to directly
transfer current to rotational energy; but ferrite cores may reduce
the wasted heat from this negative approach.
None of what I've written proves that there is no anomaly. But it
does mean that no anomaly has been demonstrated, at all. Most of the
power generated by the battery is going into heat. Steorn simply
claims "all." But only a small part of that energy would be
sufficient to accelerate the rotor. Nothing that you'd necessarily
see on an oscilloscope, and certainly not with a 5A meter simply
measuring current flow of 100 mA stated. A tiny deflection! (and
transient currents wouldn't be shown).
So, the phase where work is being done by the battery is the phase when
the coil is energized and the magnet and coil are moving apart.
Yes. And that work must be maintained during this phase, or the rotor
is slowed. It's simply upside-down.
To see where and how much energy is being pumped into the system to do
useful work, look at the induced voltage in the coil during that phase.
Mmmmm.... This is obviously the only place where energy can be dumped
into the rotor. And I think that the description is intuitively correct.
Say it again, louder: Linear superposition! Sure, the magnetization of
the core changes, but to a very large extent, when you "cancel" the
field of the core, you're looking at the coil and core fields adding
linearly. The field of the coil is still there, still interacting with
the environment, but it's hidden by the superposed field of the core.
I think this is correct. One proof that the field is still there, by
the way, is what happens when you open the switch and the field
collapses? Pop! -- if you haven't set up some device to handle the
back-EMF, you will burn out the switch. What is the diode for in the
Steorn demo?
