----- Original Message ----
> From: Abd ul-Rahman Lomax <a...@lomaxdesign.com>
> To: "vortex-l@eskimo.com" <vortex-l@eskimo.com>
> Cc: "vortex-l@eskimo.com" <vortex-l@eskimo.com>
> Sent: Mon, January 18, 2010 12:55:23 PM
> Subject: Re: [Vo]:Back EMF: Sean may be right
>
> At 02:46 PM 1/17/2010, Abd ul-Rahman Lomax wrote:
>
> > On Jan 17, 2010, at 12:06 PM, Harry Veeder wrote:
> >> How do you know? With regular bearings it may require more energy
> >> then the system can
> >> generate.
> >
> > Isn't that my point? They are drawing relatively high power from the
> > battery. If all of that ends up as heat, and twice as much is going
> > into rotational energy, there should be no problem with bearings. But
> > hey , if I have the math wrong, let's say they haven't given us the
> > info to show it. I didn't do actual calculations, just seat of the
> > pants estimation.
>
> Suppose that Sean is right. So, they put a controllable brake on the rotor.
> It
> could be done by using an induction coil to extract rotational energy from
> the
> rotor and dump it into a resistor to generate heat. They let the thing fire
> up,
> then move the induction coil in until rotor acceleration is zero. Or lower
> the
> resistance value until that point.
>
> How much power is being extracted from the battery? How much heat is being
> generated there (mostly in the toroids)?
>
> And how much heat, in this steady-state situation, constant RPM, is being
> generated in the resistor?
>
> If Sean's claim of 2:1 is correct, say at some rotational rate, then twice as
> much power would be dissipated in the brake resistor. Very easy to measure
> the
> resistor dissipation, the waveform would be simple, no complications at all.
>
> But this is what classical understanding would predict: the resistor would be
> dissipating only a small fraction of the energy being dissipated in the
> toroid
> circuit, representing some small deviation from the claim of 100% generation
> of
> heat of the current in that circuit. Some (small) fraction of that current is
> converted into rotor energy. And that's why very low friction bearings are
> required. It's a very low percentage, and being so low, it's not easy to see,
> the measurement accuracy would have to be high, and with transients, which is
> where it's happening (during the turn-on and turn-off of the circuit), such
> measurement is quite difficult.
>
> This is what I'd predict if careful analysis is done: the continuous energy
> that
> can be extracted from the rotor, by the induction pickup, is within the noise
> in
> the measurement of energy input from the battery, minus energy dissipation in
> the toroid circuit, or it is observable as a deficit from that circuit,
> missing
> energy there, as would exist with a "classic pulse motor."
>
> There would be a smaller missing component of energy, so the efficiency isn't
> actually 100%, because some energy will be radiated as RF. So (work in the
> toroid circuit) minus (work in the induction circuit) will be positive, if
> measured accurately enough, or will be in the noise, if not. If Sean's claim
> is
> true, this difference will be very negative, the dissipation in the pickup
> coil
> will be double that in the toroid circuit.
>
> Simple hypothesis to test. Now, obvious question that will be asked, and this
> kind of question has been asked many times. "Why haven't they thought of
> this?"
>
I noticed on the Steorn forum there is talk of a "punch line" that Steorn will
give at the end of the month. Perhaps the test you describe is it.
> Well, I assume that they have thought of it, if fact, the alternative is to
> assume that in spite of having the money to bring in serious expertise, they
> are
> seriously stupid. And I rather doubt that.
>
> Abd's version of an old maxim:
>
> Never ascribe to stupidity what may be effective marketing.
Harry
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