Author Topic: EM Drive Developments Thread 1  (Read 764627 times)

Offline aero

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Re: EM Drive Developments
« Reply #2160 on: 10/16/2014 07:39 PM »
Yes, Applause for your great effort. --- now, if it could only talk ...

I'll try to convert these to conventional nomenclature.

Quote
a^-2 b^-2 L^2  Q^1  P^1  F^-1 c^-1   (a^-2 + L^-2)^-1   0.15   0.61 *
a^-1 b^-2 L^1  Q^1  P^1  F^-1 c^-1   (a^-1 + L^-1)^-2   0.13   0.58 *

compared to McCulloch's

a^0  b^0  L^1  Q^1  P^1  F^-1 c^-1   |a^-1 - b^-1|^1    0.46   0.61 <-


AIUI - a = w_big, b = w_small and the others are as always, so:

a^-2 b^-2 L^2  Q^1  P^1  F^-1 c^-1   (a^-2 + L^-2)^-1   0.15   0.61 *
force = QP/fc * (L^2/ab^2)/(a^2 + L^2)

and

a^-1 b^-2 L^1  Q^1  P^1  F^-1 c^-1   (a^-1 + L^-1)^-2   0.13   0.58 *
force = QP/fc * (L/a*b^2)/(1/a + 1/L)^2

and McCulloch's formula,
a^0  b^0  L^1  Q^1  P^1  F^-1 c^-1   |a^-1 - b^-1|^1    0.46   0.61 <-
force = QP/fc * L * (1/a - 1/b) which is not what you wrote.

and this is interesting, but I'm still wondering about the effect of L = cavity height, which this doesn't address.
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Offline JohnFornaro

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Re: EM Drive Developments
« Reply #2161 on: 10/16/2014 07:43 PM »
Great frobnicating

This is a family wave site, buddy.  Don't make me come back from the future and tell you again.
Sometimes I just flat out don't get it.

Online Rodal

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Re: EM Drive Developments
« Reply #2162 on: 10/16/2014 07:47 PM »
Yes, Applause for your great effort. --- now, if it could only talk ...

I'll try to convert these to conventional nomenclature.

Quote
a^-2 b^-2 L^2  Q^1  P^1  F^-1 c^-1   (a^-2 + L^-2)^-1   0.15   0.61 *
a^-1 b^-2 L^1  Q^1  P^1  F^-1 c^-1   (a^-1 + L^-1)^-2   0.13   0.58 *

compared to McCulloch's

a^0  b^0  L^1  Q^1  P^1  F^-1 c^-1   |a^-1 - b^-1|^1    0.46   0.61 <-


AIUI - a = w_big, b = w_small and the others are as always, so:

a^-2 b^-2 L^2  Q^1  P^1  F^-1 c^-1   (a^-2 + L^-2)^-1   0.15   0.61 *
force = QP/fc * (L^2/ab^2)/(a^2 + L^2)

and

a^-1 b^-2 L^1  Q^1  P^1  F^-1 c^-1   (a^-1 + L^-1)^-2   0.13   0.58 *
force = QP/fc * (L/a*b^2)/(1/a + 1/L)^2

and McCulloch's formula,
a^0  b^0  L^1  Q^1  P^1  F^-1 c^-1   |a^-1 - b^-1|^1    0.46   0.61 <-
force = QP/fc * L * (1/a - 1/b) which is not what you wrote.

and this is interesting, but I'm still wondering about the effect of L = cavity height, which this doesn't address.

No, F=experimentally measured force.  F not equal frequency, kernosabe

Kernosabe not allowed to include frequency (f) in the denominator of any of these formulas if also simultaneously including c/L

The cat already prescribed MeasuredFrequency = c/L; therefore L = c / MeasuredFrequency;

f not allowed here. And JohnFornaro coming from the future with his time machine warned that

frobnicating not allowed either
« Last Edit: 10/16/2014 08:15 PM by Rodal »

Offline JohnFornaro

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Re: EM Drive Developments
« Reply #2163 on: 10/16/2014 07:52 PM »
It is even a mystery why NASA Eagleworks chose to test at those particular frequencies, as remarked by Ludwick.

Somebody must think that there's some kind of "sweet spot" around those two frequencies.  Why they apparently did not see to it that their bancdwidth was better controlled, I have no idea.
Sometimes I just flat out don't get it.

Offline aero

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Re: EM Drive Developments
« Reply #2164 on: 10/16/2014 08:03 PM »
Try again.
AIUI - a = w_big, b = w_small and the others are as always, so:

a^-2 b^-2 L^2  Q^1  P^1  F^-1 c^-1   (a^-2 + L^-2)^-1   0.15   0.61 *
force = QP/c * (L^2/ab^2)/(a^2 + L^2)

and

a^-1 b^-2 L^1  Q^1  P^1  F^-1 c^-1   (a^-1 + L^-1)^-2   0.13   0.58 *
force = QP/c * (L/a*b^2)/(1/a + 1/L)^2

and McCulloch's formula,
a^0  b^0  L^1  Q^1  P^1  F^-1 c^-1   |a^-1 - b^-1|^1    0.46   0.61 <-
force = QP/c * L * (1/a - 1/b) which is not what you wrote.

and this is interesting, but I'm still wondering about the effect of L = cavity height, which this doesn't address.

Quote
MeasuredFrequency = c/L; therefore L = c / MeasuredFrequency;

But I don't buy that. L need only have units of length. That's why I asked you to test L =  cavity height .

And by the way, I am not kernosabe. Or kemosabe either .
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Online Rodal

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Re: EM Drive Developments
« Reply #2165 on: 10/16/2014 08:09 PM »
Quote
MeasuredFrequency = c/L; therefore L = c / MeasuredFrequency;

But I don't buy that. L need only have units of length. That's why I asked you to test L =  cavity height .
OK, but that becomes @aero's formula then. McCulloch's formula has MeasuredFrequency = c/L; therefore L = c / MeasuredFrequency

@frobnicat is best to explore L as floating parameter, with his Infinite number of formulas exploration

And by the way, I am not kernosabe. Or kemosabe either .
Oh, OK, I fixed that  :)
« Last Edit: 10/16/2014 08:11 PM by Rodal »

Offline frobnicat

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Re: EM Drive Developments
« Reply #2166 on: 10/16/2014 08:32 PM »
Try again.
AIUI - a = w_big, b = w_small and the others are as always, so:

a^-2 b^-2 L^2  Q^1  P^1  F^-1 c^-1   (a^-2 + L^-2)^-1   0.15   0.61 *
force = QP/c * (L^2/ab^2)/(a^2 + L^2)

er, try again ?
force = QP/c * (L^2/ab^2)/(1/a^2 + 1/L^2)
        = QP/c * (L^2/ab^2) (aL)^2/(a^2 + L^2)
        = QP/c * (L^4/b^2)/(a^2 + L^2)
        = QP/c * L^4/((ab)^2 + (Lb)^2)

Is that it ?
My system isn't hooked to symbolic automation like mathematica, sorry.

Quote

a^-1 b^-2 L^1  Q^1  P^1  F^-1 c^-1   (a^-1 + L^-1)^-2   0.13   0.58 *
force = QP/c * (L/a*b^2)/(1/a + 1/L)^2


seems ok

Quote
and McCulloch's formula,
a^0  b^0  L^1  Q^1  P^1  F^-1 c^-1   |a^-1 - b^-1|^1    0.46   0.61 <-
force = QP/c * L * (1/a - 1/b) which is not what you wrote.

I wrote
F = P Q L/c (1/b - 1/a)
because there is an absolute value and I know what makes that positive and didn't wrote the 4 lines of code to automatise the process in quick and dirty mode. Program is already a mess and needs refactoring.

Quote
and this is interesting, but I'm still wondering about the effect of L = cavity height, which this doesn't address.

Quote
MeasuredFrequency = c/L; therefore L = c / MeasuredFrequency;

But I don't buy that. L need only have units of length. That's why I asked you to test L =  cavity height .


For me L is just a convenient way to input the frequency. The conversion factor, c, is unlikely to see great changes soon, and taking the inverse makes no difference further than negating the exponents. It is convenient precisely because it has natural units of length and can mix easily with a and b.

edit: I like to see  F = P/c  times dimensionless_factor  because for the only both experimentally proven and theoretically understood propellantless propulsion (you know, my friend, the photon rocket) we have this beautiful (but also hopelessly scant) formula F = P/c times one.
« Last Edit: 10/16/2014 08:44 PM by frobnicat »

Offline frobnicat

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Re: EM Drive Developments
« Reply #2167 on: 10/16/2014 09:42 PM »
I'm surprised nobody bites on this nice looking one

F = 13100 P/c ab(1/b-1/a)^2
or
F = 13100 P/c (a-b)^2/(ab)

( a^1  b^1  L^0  Q^0  P^1  F^-1 c^-1   |a^-1 - b^-1|^2 ) / mean value (without log)
 -> 1.16   1.05   1.05   0.71   1.35   2.42   0.34

For comparison, McCulloch's (which is great, I don't contest)
(a^0  b^0  L^1  Q^1  P^1  F^-1 c^-1   |a^-1 - b^-1|^1 ) / mean value (without log)
->  0.50   1.16   0.81   0.87   0.89   3.95   0.70

(as per the order of the seven rows tabulated data)

Alright there is a big fudge factor of 13100, that looks like the ballpark of Q values, but note that it doesn't move, it is still 13100 even with Q values going from 5900 to 50000. First and fourth values 1.16 and 0.71 ratio 1.63, no more relative deviation than MiHsC 0.50 and 0.87 ratio 1.74

To me this is indicative that this former formula is as good at predicting an effect independent of Q than the later at indicating a linear dependency on Q. Introducing a constant is a lot of information added to fit the data (considering the sparsity of data the risk of overfitting is great) but it also discards two parameters Q and Lambda (or frequency) so is simpler in this respect. What would 13100 stand for ? Let me see... something vaguely around the squared inverse of the fine structure constant for instance ?

Do I have an agenda ? Of course I have an agenda. But this isn't numerology.
And this can wait until tomorrow.

Online Rodal

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Re: EM Drive Developments
« Reply #2168 on: 10/16/2014 09:56 PM »
I'm surprised nobody bites on this nice looking one

F = 13100 P/c ab(1/b-1/a)^2
or
F = 13100 P/c (a-b)^2/(ab)

( a^1  b^1  L^0  Q^0  P^1  F^-1 c^-1   |a^-1 - b^-1|^2 ) / mean value (without log)
 -> 1.16   1.05   1.05   0.71   1.35   2.42   0.34

For comparison, McCulloch's (which is great, I don't contest)
(a^0  b^0  L^1  Q^1  P^1  F^-1 c^-1   |a^-1 - b^-1|^1 ) / mean value (without log)
->  0.50   1.16   0.81   0.87   0.89   3.95   0.70

(as per the order of the seven rows tabulated data)

Alright there is a big fudge factor of 13100, that looks like the ballpark of Q values, but note that it doesn't move, it is still 13100 even with Q values going from 5900 to 50000. First and fourth values 1.16 and 0.71 ratio 1.63, no more relative deviation than MiHsC 0.50 and 0.87 ratio 1.74

To me this is indicative that this former formula is as good at predicting an effect independent of Q than the later at indicating a linear dependency on Q. Introducing a constant is a lot of information added to fit the data (considering the sparsity of data the risk of overfitting is great) but it also discards two parameters Q and Lambda (or frequency) so is simpler in this respect. What would 13100 stand for ? Let me see... something vaguely around the squared inverse of the fine structure constant for instance ?

Do I have an agenda ? Of course I have an agenda. But this isn't numerology.
And this can wait until tomorrow.

Well, obviously

 (a-b)^2/(ab)  = ( (a/b -1) + (b/a -1)) 

or

 (a-b)^2/(ab)  = ( (RR - 1) + (1/RR - 1))

which is a symmetrized measure of the distance from unity of the relative ratio (RR = a / b) between the two diameters of the bases of the truncated cone.  (This measure is zero for RR =1 and it goes to Infinity either as RR --> Infinity or as RR --> 0)

But how can the photons produce a net thrust force ?

and a force exceeding the one of a photon rocket ?

« Last Edit: 10/16/2014 10:26 PM by Rodal »

Offline RotoSequence

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Re: EM Drive Developments
« Reply #2169 on: 10/16/2014 10:07 PM »
I guess memetic replies aren't appreciated by the mods.

I don't trust the photon thrust explanation when the measured thrust is larger than that of a photon rocket.
« Last Edit: 10/16/2014 10:07 PM by RotoSequence »

Offline aero

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Re: EM Drive Developments
« Reply #2170 on: 10/16/2014 10:26 PM »
I'm surprised nobody bites on this nice looking one

F = 13100 P/c ab(1/b-1/a)^2
or
F = 13100 P/c (a-b)^2/(ab)

( a^1  b^1  L^0  Q^0  P^1  F^-1 c^-1   |a^-1 - b^-1|^2 ) / mean value (without log)
 -> 1.16   1.05   1.05   0.71   1.35   2.42   0.34

For comparison, McCulloch's (which is great, I don't contest)
(a^0  b^0  L^1  Q^1  P^1  F^-1 c^-1   |a^-1 - b^-1|^1 ) / mean value (without log)
->  0.50   1.16   0.81   0.87   0.89   3.95   0.70

(as per the order of the seven rows tabulated data)

Alright there is a big fudge factor of 13100, that looks like the ballpark of Q values, but note that it doesn't move, it is still 13100 even with Q values going from 5900 to 50000. First and fourth values 1.16 and 0.71 ratio 1.63, no more relative deviation than MiHsC 0.50 and 0.87 ratio 1.74

To me this is indicative that this former formula is as good at predicting an effect independent of Q than the later at indicating a linear dependency on Q. Introducing a constant is a lot of information added to fit the data (considering the sparsity of data the risk of overfitting is great) but it also discards two parameters Q and Lambda (or frequency) so is simpler in this respect. What would 13100 stand for ? Let me see... something vaguely around the squared inverse of the fine structure constant for instance ?

Do I have an agenda ? Of course I have an agenda. But this isn't numerology.
And this can wait until tomorrow.

Well, obviously

 (a-b)^2/(ab)  = ( (a/b -1) + (b/a -1)) 

or

 (a-b)^2/(ab)  = ( (AR - 1) + (1/AR - 1))

which is a symmetrized measure of the distance from unity of the aspect ratio (AR = a / b) between the two diameters of the bases of the truncated cone.  (This measure is zero for AR =1 and it goes to Infinity either as AR --> Infinity or as AR --> 0)

But how can the photons produce a net thrust force ?

and a force exceeding the one of a photon rocket ?

Well Prof. M told us, but we threw it out with this.

Quote
The cat already prescribed MeasuredFrequency = c/L; therefore L = c / MeasuredFrequency;

And I am sorry, but I don't see anything here but someone quoting someone else. Can you show me the original source statement, or better, proof? I can show you the original source statement that L is the Unruh wavelength here:

http://physicsfromtheedge.blogspot.it/2014/10/mihsc-vs-emdrive-data-1.html

Quote
In MiHsC the inertial mass (mi) is modified as mi=m(1-L/4T) where m is the unmodified mass, L is the Unruh wavelength determined by the acceleration, and T is the Hubble distance

snip

What if the resonant cavity walls acted like a Hubble horizon, especially for Unruh waves of a similar length (as they are in this case)? Then the inertial mass of the photons would increase towards the cavity's wide end, since more Unruh waves would fit there, since mi=m(1-L/2w), where w is the cavity width. The force carried by the photons then increases by this factor as they go from the narrow end (width w_small) towards the wide end (width w_big). The force difference between ends is

 dF = (PQ/c)*((L/w_big)-(L/w_small)) = (PQ/f)*((1/w_big)-(1/w_small)).

If we consider L to be the RF drive wavelength, then how do we justify talking about the Unruh effect and how it may interact with the photons to cause the excessive thrust? If L is not the RF wavelength then it could be just about anything although it seems that it could be related to cavity dimensions. Ask Prof. M, but I think it doesn't have to be.
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Online Rodal

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Re: EM Drive Developments
« Reply #2171 on: 10/16/2014 10:51 PM »
If we consider L to be the RF drive wavelength, then how do we justify talking about the Unruh effect and how it may interact with the photons to cause the excessive thrust? If L is not the RF wavelength then it could be just about anything although it seems that it could be related to cavity dimensions. Ask Prof. M, but I think it doesn't have to be.
OK point well taken.  You are correct, that is the Unruh wavelength explanation.

Here is the practical problem. 

There are an infinite number of Unruh wavelengths, and they have an energy spectrum.

I imagine that there is an Unruh wavelength that best fits.  Which Unruh wavelength to take?  Assume that the longest wavelength that fits is the most energetic?  That fits in what lengh?  (Which way do the wavelengths fit in the cavity? along the longitudinal axis of revolution of the cone?)

How do we decide what "L" to use in the analysis?  For NASA Eagleworks? For Shawyer?

I understand these are the Shawyer dimensions calculated:


@aero                                                                McCulloch's table

w_big = 0.28 meters                                          0.28  meters        AGREE
w_small = 0.18375 meters                                 0.04 meters         DISAGREE
height = 0.2975 meters

w_big    0.2800  meters                                      0.16 meters         DISAGRE
w_small    0.0778 meters                                    0.08 meters         AGREE
height 0.3811 meters

which are discrepant as noted

and what are the L's to use?
« Last Edit: 10/16/2014 11:38 PM by Rodal »

Offline aero

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Re: EM Drive Developments
« Reply #2172 on: 10/16/2014 11:44 PM »
If it is an Unruh wave, it is initiated by acceleration of the cavity walls. Which walls are accelerated by the RF photons? I think it is the end circular walls. That is, the RF waves resonate parallel to the axis of symmetry. So the Unruh waves also propagate parallel to the axis of symmetry.

What are the Unruh wave wavelengths? They are either constrained by the cavity end separation or they are unique to the end from which they propagate. They need not propagate from both ends, that is, one end could act as a horizon and emit a wave while the other does not but this seems unlikely. It seems more likely that the ends emit Unruh waves of different wavelength. If they are not coupled to each other, that is. But if they are coupled then cavity dimensions play a role in fixing the wavelength?

But don't get to hung up on the actual value of the wavelength. If it exists at all, then imagine what the photon must see as it approached the wall. Nothing of course, the photon is moving at the speed of light so can only see behind and to angles to the rear. But from the Unruh effect, that wall is hot so like a blind cat on a hot stove, the photon departs with more energy than it arrived with. Its frequency or its mass is up-shifted as is its momentum. How much? I think that gets us back to the Unruh effect. And what is really up-shifted? Its inertial mass of course because that is what put us on this path in the first place.
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Offline aero

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Re: EM Drive Developments
« Reply #2173 on: 10/17/2014 12:25 AM »
@aero                                                                McCulloch's table
Demonstrator by ratio
w_big = 0.28 meters                                          0.28  meters        AGREE
w_small = 0.18375 meters                                 0.04 meters         DISAGREE
height = 0.2975 meters

Demonstrator by photo
w_big = 0.28 meters                                          0.28  meters        AGREE
w_small = 0.0778 meters                                 0.04 meters         DISAGREE Whatever works
height = 0.381 meters

Experimental by photo
w_big    0.16 meters                                      0.16 meters         DISAGRE Agree
w_small    0.0778 meters                                    0.08 meters         AGREE
height    0.177 meters


You don't think Shawyer just extended the big end of the Experimental model to make the Demonstrator model, do you?
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Offline JohnFornaro

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Re: EM Drive Developments
« Reply #2174 on: 10/17/2014 12:55 AM »
And by the way, I am not kernosabe. Or kemosabe either.

He knoweth not for whom the bell tolleth.

If we consider L to be the RF drive wavelength, then how do we justify talking about the Unruh effect and how it may interact with the photons to cause the excessive thrust? If L is not the RF wavelength then it could be just about anything although it seems that it could be related to cavity dimensions. Ask Prof. M, but I think it doesn't have to be.

OK point well taken.  You are correct, that is the Unruh wavelength explanation.

In my equationless style, I'm still not on board with the HYPOTHETICAL Unruh wave explanation.  Further, since there must be an integral number of these faith based waves in the cavity, and since resonance is THE operative factor, there should have been, from the summa cavea arachis at any rate, much tighter control over the bandwidth of the wavelength sent to the device.

What you guys are talking about is not making sense.  Not sayin' you're talking nonsense.  You're still talking about the copper geometry as having some special refractive index which works at 1.9xxx GHz, using waves which have not been seen.

It's rough being me.  But somebody has to do it.
« Last Edit: 10/17/2014 01:03 AM by JohnFornaro »
Sometimes I just flat out don't get it.

Online Rodal

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Re: EM Drive Developments
« Reply #2175 on: 10/17/2014 01:18 AM »
And by the way, I am not kernosabe. Or kemosabe either.

He knoweth not for whom the bell tolleth.

If we consider L to be the RF drive wavelength, then how do we justify talking about the Unruh effect and how it may interact with the photons to cause the excessive thrust? If L is not the RF wavelength then it could be just about anything although it seems that it could be related to cavity dimensions. Ask Prof. M, but I think it doesn't have to be.



OK point well taken.  You are correct, that is the Unruh wavelength explanation.

In my equationless style, I'm still not on board with the HYPOTHETICAL Unruh wave explanation.  Further, since there must be an integral number of these faith based waves in the cavity, and since resonance is THE operative factor, there should have been, from the summa cavea arachis at any rate, much tighter control over the bandwidth of the wavelength sent to the device.

What you guys are talking about is not making sense.  Not sayin' you're talking nonsense.  You're still talking about the copper geometry as having some special refractive index which works at 1.9xxx GHz, using waves which have not been seen.

It's rough being me.  But somebody has to do it.

Kernosabe, the drums go ooompah ooompah ooompah,  the bongos go bonga bonga bonga



and the cavity goes something like this


« Last Edit: 10/17/2014 01:51 AM by Rodal »

Offline aero

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Re: EM Drive Developments
« Reply #2176 on: 10/17/2014 05:35 AM »
Quote
OK point well taken.  You are correct, that is the Unruh wavelength explanation.

Here is the practical problem. 

There are an infinite number of Unruh wavelengths, and they have an energy spectrum.

I can't find Prof. M's equation with Q*L replaced with a constant, but this equation

F = 13100 P/c ab(1/b-1/a)^2

gives us an idea of how to find the values of L. First find them numerically, then relate them to the dimensions of the device, if they relate.

Replace the number, 13100 in the equation with the product Q*L then the values of L that satisfy the equations for each experiment are:

     "Shawyer (2008) a"    1.913 m
     "Shawyer (2008) b"    0.277 m
       "Juan (2012) TE011"    0.390 m
       "Juan (2012) TE012"    0.367 m
       "Brady et al. (2014) a"    1.326 m
       "Brady et al. (2014) b"    0.298 m
     "Brady et al. (2014) c"    1.742 m

As can be seen, Shawyer b and both Jauns have L values that fit the within cavity dimensions, which is around 0.38 m. Unfortunately by forcing the fit above I have forced all of the errors from the experiments and the analysis into the values of L.

I wonder if this advances our search. Two of the 7 experiments are satisfied with L = cavity height, and one has L < cavity height. The only other one that is close is the Brady outlier. I don't know what to make of that. I do know that I should use Prof. M's original formula, not the one with the constant factor. Maybe later.

Its later. Prof. M's 1-D equation is not satisfied with L chosen to force fit the experimental data. That is, of course the numbers are calculated but the values of L are all to small to relate to the cavity. In fact, except for Shawyer a, they are all smaller than the RF wavelength. Close, but smaller. Well, the Brady outlier is much smaller, not even close to the RF wavelength.

Is there a chance that the formula above, using ab(1/b-1/a)^2, an area like expression, could end up being similar to Prof. M's 3-D model that he is working on? That is, could

dF = Q*L* P/c ab(1/b-1/a)^2

be a 3-D representation of the MiHsC model. I guess I should ask Prof. M himself.
« Last Edit: 10/17/2014 06:22 AM by aero »
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Re: EM Drive Developments
« Reply #2177 on: 10/17/2014 12:04 PM »
....
I wrote a small program to generate some exhaustive search on formulas upon the relevant factors then sieving those formulas that fit the available data. This is completely theoretically agnostic but it does check for dimensional consistency (as far as kg m s units are concerned). The search goes on for any product of the terms a  b  L  Q  P  F  c  (respectively w_big   w_small   wavelength=c/Freq   Power   Thrust    Speed_of_light) with all possible whole exponents from -2 to +2 (going through 0) and tries to equal 1 (with the experimental data). It also tries an "extended" term (exterm) that is a combination of 2 homogeneous terms ( that is  a  b  or L ) at any power -2 to +2 through any of the operators  sum  difference  geometrical_average, and then to any power -2 to +2.
This does cover the formula by McCulloch but not Shawyer's.

Example of understanding the following dumps : McCulloch's formula reads
a^0  b^0  L^1  Q^1  P^1  F^-1 c^-1   |a^-1 - b^-1|^1  =  1
or said otherwise  F = P Q L/c (1/b - 1/a)
Note that the difference operator for the extended term is enclosed in absolute value (manual permutation needed to remove it).

The sieve goes like that : use the formula on each of the seven data points to generate a value hopefully close to 1. If it is not close to 1 but close to a given value (say 2) for all the data points then we have a constant fudge factor, but if the standard deviation around it is small this is still interesting : a strong relation still holds between the terms in such formula. The mean and deviation are calculated in log space, that is a mean of 0 is a best result (formula gives values around 1) while a mean of -1 or +1 says the formula gives values e (=2.72) times too low or too big.

Data input :


/// With maxes for ranges
t_data data_in[Nrec] =
{
    //                                 w_big  w_small  lambda      Q     power   force
    {"Shawyer (2008) a",        1.0 ,  16    ,  8    , C/2.45  ,  5900 ,  850   , 16       },
    {"Shawyer (2008) b",        1.0 ,  28    ,  4    , C/2.45  , 45000 , 1000   , 214      },
    {"Juan (2012) TE011",       1.0 ,  28    ,  4    , C/2.5   , 32000 , 1000   , 214      },
    {"Juan (2012) TE012",       1.0 ,  28    ,  4    , C/2.45  , 50000 , 1000   , 315      },
    {"Brady et al. (2014) a",   1.0 ,  24.75 , 16.5  , C/1.933 ,  7320 ,   16.9 ,   0.0912 },
    {"Brady et al. (2014) b",   1.0 ,  24.75 , 16.5  , C/1.937 , 18100 ,   16.7 ,   0.0501 },
    {"Brady et al. (2014) c",   1.0 ,  24.75 , 16.5  , C/1.88  , 22000 ,    2.6 ,   0.0554 },
};
...

Could you please re-run all the cases with the same input except to take this outlier out ?:

   {"Brady et al. (2014) b",   1.0 ,  24.75 , 16.5  , C/1.937 , 18100 ,   16.7 ,   0.0501 }

In other words, please re-run with:

Data input :

{
    //                                 w_big  w_small  lambda      Q     power   force
    {"Shawyer (2008) a",        1.0 ,  16    ,  8    , C/2.45  ,  5900 ,  850   , 16       },
    {"Shawyer (2008) b",        1.0 ,  28    ,  4    , C/2.45  , 45000 , 1000   , 214      },
    {"Juan (2012) TE011",       1.0 ,  28    ,  4    , C/2.5   , 32000 , 1000   , 214      },
    {"Juan (2012) TE012",       1.0 ,  28    ,  4    , C/2.45  , 50000 , 1000   , 315      },
    {"Brady et al. (2014) a",   1.0 ,  24.75 , 16.5  , C/1.933 ,  7320 ,   16.9 ,   0.0912 },

    {"Brady et al. (2014) c",   1.0 ,  24.75 , 16.5  , C/1.88  , 22000 ,    2.6 ,   0.0554 },
};

I would like to see how the formula parameters behave with this outlier taken out.

Thanks

Offline aero

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Re: EM Drive Developments
« Reply #2178 on: 10/17/2014 04:06 PM »
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I would like to see how the formula parameters behave with this outlier taken out.

Yes. The Brady outlier certainly shows us something but it doesn't show us how the thruster works ideally. It shows how it works when something goes wrong. That's important to know but not useful in the context of discovering the ideal operational model and parameters.

For our purposes now of discovering the ideal operational model and parameters, we should avoid outliers when they have been identified. Once the data is evaluated with Brady b" removed we can consider if perhaps Shawyer a" isa  less than ideal case as well.
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Re: EM Drive Developments
« Reply #2179 on: 10/17/2014 04:44 PM »
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I would like to see how the formula parameters behave with this outlier taken out.

Yes. The Brady outlier certainly shows us something but it doesn't show us how the thruster works ideally. It shows how it works when something goes wrong. That's important to know but not useful in the context of discovering the ideal operational model and parameters.

For our purposes now of discovering the ideal operational model and parameters, we should avoid outliers when they have been identified. Once the data is evaluated with Brady b" removed we can consider if perhaps Shawyer a" isa  less than ideal case as well.

I think that placing this outlier in the data masks the importance of Q.
Taking it out of the data may show again the importance of Q.

As @aero states, imagine that this thruster works based on resonance (as was the expectation by all the researchers in the US, UK and China) and that one cannot control the bandwidth adequately at high Q (as pointed out by Ludwick).

Due to frequency drift, one ends up with tests that are in resonance and tests (like the outlier) that drift out of resonance and produce very low experimental force.

To understand the mechanism we have to look at the data with the outlier included (done) and with the outlier excluded.

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