Author Topic: EM Drive Developments Thread 1  (Read 762358 times)

Offline aceshigh

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Re: EM Drive Developments
« Reply #3220 on: 11/14/2014 03:53 PM »
A careful reading of your line of questioning reveals to me some inaccuracy in your approach.

You ask, "bcause they donīt KNOW how to do it or because of budget constraints".  Budget is not the cause for lack of results.  If they do know how to do it  (not that "do it") they have not so demonstrated the phenomena.

if I was making a question, there was no inaccuracy in my line of approach. That's why it was a question. You just answered my question there, thus I donīt understand why you think there was an inaccuracy in my question. If there was innacuracy in a QUESTION you wouldnīt know how to answer it (but you did)


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The potential economic stakes are very high, but the theoretical costs, if you will, are also very high.

that's what I was wanting to know.

Online aero

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Re: EM Drive Developments
« Reply #3221 on: 11/14/2014 04:32 PM »
Later, if the EM Drive is demonstrated to produce thrust, then what kind of test could be done to detect the source of the momentum, the reaction mass? With a chemical rocket you can see the reaction mass, fire, and similarly for an ion thruster. Would a "Cloud chamber" allow visualization of the EM thruster reaction mass?

Knowing the character of the reaction mass would go a long way toward developing the correct theory of operation.
Retired, working interesting problems

Offline Rodal

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Re: EM Drive Developments
« Reply #3222 on: 11/14/2014 04:51 PM »
Later, if the EM Drive is demonstrated to produce thrust, then what kind of test could be done to detect the source of the momentum, the reaction mass? With a chemical rocket you can see the reaction mass, fire, and similarly for an ion thruster. Would a "Cloud chamber" allow visualization of the EM thruster reaction mass?

Knowing the character of the reaction mass would go a long way toward developing the correct theory of operation.
That's why Dr. White proposed (in his August 2014 NASA Ames lecture) to measure "the wake in the Quantum Vacuum" left by the EM Drive as one of his future experimental steps. 

Recall that Dr. White proposes that the EM Drive is like a submarine using a propeller to push against the Quantum Vacuum (that acts according to Dr. White as the surrounding water in a submarine's propeller).



Dr. White said at the conference he had discussions with other scientists at Ames, probably the idea to use "another EM Drive behind the thrusting EM Drive to measure the wake left in the Quantum Vacuum" came as a result of those discussions.

____
PS: I think that the idea that the EM Drive is using Quantum Vacuum electron-positron virtual-particles proposed by Dr. White and that the EM Drive is like a submarine propeller is non-viable and negated by the measured response that shows time constants exceeding by several orders of magnitude the electromagnetic and particle physics wave periods.  Also virtual particles are called virtual for good reason and there is nothing in the EM Drives with enough energy to make them real to be used as water is used by a submarine to propel itself.   (   http://profmattstrassler.com/articles-and-posts/particle-physics-basics/virtual-particles-what-are-they/   )
« Last Edit: 11/14/2014 05:14 PM by Rodal »

Offline Ron Stahl

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Re: EM Drive Developments
« Reply #3223 on: 11/14/2014 05:45 PM »
One really wants to find a separate test for each of the proposed models, just as one looks for a separate test for each of the possible spurious sources.  For QVF, the fact that these thrusters do not function with DC applied seems to me ample falsification of the QVF model.  I have not seen any sort of response to this challenge and it's been years since the first challenges to QVF came in from lack of DC instigated thrust.

To check for M-E as the source, one wants to use a laser dopper vibrometer of sufficient frequency such as the Polytech UHF120:

http://www.polytec.com/us/products/vibration-sensors/microscope-based-systems/uhf-120-ultra-high-frequency-vibrometer/

If the source of thrust is M-E, then we should find 2 separate and distinct acoustic vibrations, one the second harmonic of the other.  Note that twice the drive frequency (what would be produced through electrostriction) of the E-M thruster is above the frequency of the above device, and it is probably cheaper to drive a new resonator at lower frequency than try to build your own microwave vibrometer, though the Materials Physics Lab in Helsinki has one that operates up to 40 Ghz, and I believe MIT has a very fast one good for microwave application as well.  The main trouble with this method for the E-M thruster is peering inside the truncated cone while it's operating.  I think you'd have to put in some sort of window but not sure how that would work.  Honestly, it might be easier to just test a real M-E design rather than something producing thrust by accident, which is what the Shawyer device may be doing.
« Last Edit: 11/14/2014 05:49 PM by Ron Stahl »

Offline Rodal

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Re: EM Drive Developments
« Reply #3224 on: 11/14/2014 06:28 PM »
One really wants to find a separate test for each of the proposed models, just as one looks for a separate test for each of the possible spurious sources.  For QVF, the fact that these thrusters do not function with DC applied seems to me ample falsification of the QVF model.  I have not seen any sort of response to this challenge and it's been years since the first challenges to QVF came in from lack of DC instigated thrust.

To check for M-E as the source, one wants to use a laser dopper vibrometer of sufficient frequency such as the Polytech UHF120:

http://www.polytec.com/us/products/vibration-sensors/microscope-based-systems/uhf-120-ultra-high-frequency-vibrometer/

If the source of thrust is M-E, then we should find 2 separate and distinct acoustic vibrations, one the second harmonic of the other.  Note that twice the drive frequency (what would be produced through electrostriction) of the E-M thruster is above the frequency of the above device, and it is probably cheaper to drive a new resonator at lower frequency than try to build your own microwave vibrometer, though the Materials Physics Lab in Helsinki has one that operates up to 40 Ghz, and I believe MIT has a very fast one good for microwave application as well.  The main trouble with this method for the E-M thruster is peering inside the truncated cone while it's operating.  I think you'd have to put in some sort of window but not sure how that would work.  Honestly, it might be easier to just test a real M-E design rather than something producing thrust by accident, which is what the Shawyer device may be doing.

Dr. White predicted (in his papers) a thrust force (from the Quantum Vacuum) acting perpendicular to both the Electric (E) and Magnetic (B) fields.  However, the measured thrust force in the Eagleworks tests is perpendicular to Dr. White's prediction: in the TE mode the measured force is parallel to the magnetic (B) axial field and in the TM mode the measured force is parallel to the electric (E) axial field.  In both resonant mode cases (TE and TM) the measured force occurs in the axial direction of the truncated cone and of the Cannae device.

Ron, don't you see a problem with  Paul March's and Dr. White's methodology in that their measured response always occurs in the axial direction of both the Cannae and truncated cone, regardless of mode (TE and TM) and that in all cases this measured force is perpendicular to Dr. White's prediction? .  The fact that Brady, March, White, et.al do not point out this huge discrepancy is very disturbing. Measuring a force response that is perpendicular to their theoretical prediction should be enough of a test to disqualify their theories.

___
PS: Note that Dr. White mentions Dr. Woodward's "similar physical construct" to back up his prediction that the force should be perpendicular to both the electric and magnetic fields, but this prediction is negated by the experimental results that show the measured (Cannae and Truncated Cone) force to be perpendicular to their predictions.
« Last Edit: 11/14/2014 06:56 PM by Rodal »

Offline Ron Stahl

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Re: EM Drive Developments
« Reply #3225 on: 11/14/2014 07:21 PM »
Ron, don't you see a problem with  Paul March's and Dr. White's methodology in that their measured response always occurs in the axial direction of both the Cannae and truncated cone, regardless of mode (TE and TM) and that in all cases this measured force is perpendicular to Dr. White's prediction?

Yes, it's a very serious problem.  Is the fact the thrust is in the wrong direction any more a problem than there is no thrust with DC?  Obviously the model is broken.  On getting the angle wrong. . .I dunno what to think.  The ARC Lite was constructed so that the thruster can be easily reoriented on the end of the balance arm, to do certain kinds of tests.  The thruster itself is really the best dummy load one can hope for, if it is pointed vertically, and both Sonny and Paul are completely familiar with this protocol and were when they designed the Eagle balance, which is based on the ARC Lite.  Obviously, this requires one know what direction the thrust ought to be in.  How they could have gotten the thrust direction incorrect is beyond me.  I have never focused much on the Shawyer resonator, but I did ask Paul about this back in 2007, as I noted the thrust was parallel with the e-field rather than orthogonal/radial.  I never got an answer back then either.  And this is why I say, that QVF is pathological science--it does not matter to those involved how wrong they are.  They just continue on anyway.  No screw up, no data, no embarrassment is enough to dissuade them.  Same with ZPF theory.   Is it 20 years now since Haisch, Rueda and Puttoff published their landmark ZPF paper in Physical Review?  In all that time, no one has ever explained what to do about the obvious violations of EEP, conservation and that it gives the wrong mass for the proton by many orders of magnitude.  It is a BROKEN theory, yet it is the thing most in the advanced propulsion field cling to.  And I hate to say this but what the heck--I'm on a roll.  The REASON these crappy theories survive is they were created by people who have the right credentials.  This is a failure of the peer system.

I should probably read the paper again to be more familiar but as I'm not a believer, it's hard to muster up the energy.  It still annoys when I see pics like what you have posted up of the MLT, a decade after it was tested then renamed the QPT by Sonny to gather funding for his lab.  Sonny was the one who complained for years that Paul's test series was invalid because he never provided vacuum.  So how is it Sonny a decade later, renames that same device and pretends he had tested it at Eagle, when the tests were done in Paul's extra bedroom a decade before?  This kind of shenanigans just boils my blood. 

BTW, the thrust from the MLT design was orthogonal to the e and b fields--axial--and was recorded on the ARC Lite but it was a very small thrust.  Just 5uN or so.  I built the 12 item test series that put the end to the MLT program, as it enabled Jim to see what was wrong with that design.
« Last Edit: 11/14/2014 07:31 PM by Ron Stahl »

Offline Mulletron

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Re: EM Drive Developments
« Reply #3226 on: 11/14/2014 07:39 PM »
Found another theory on how EMdrives might work.

http://arxiv.org/abs/1302.5690

Challenge your preconceptions, or they will challenge you. - Velik

Offline IslandPlaya

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Re: EM Drive Developments
« Reply #3227 on: 11/14/2014 07:43 PM »
Well...
What is one to make of all this?
Does anyone know about the status/existence of ongoing experiments?
Homebrew setups seem perhaps able with the knowledge on this thread to be able to answer lots of questions. However I do not have a garage.
Anyone with an idea what the next step will be?

Offline Mulletron

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Re: EM Drive Developments
« Reply #3228 on: 11/14/2014 07:44 PM »
A very scathing rebuttal of EMdrives...

http://johncostella.webs.com/shawyerfraud.pdf
Challenge your preconceptions, or they will challenge you. - Velik

Offline IslandPlaya

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Re: EM Drive Developments
« Reply #3229 on: 11/14/2014 07:46 PM »
Found another theory on how EMdrives might work.

http://arxiv.org/abs/1302.5690
Dr Rodal, Frobnicat...
If you can make sense of this well done!
I'm afraid it's above me...

Offline Rodal

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Re: EM Drive Developments
« Reply #3230 on: 11/14/2014 07:47 PM »
Found another theory on how EMdrives might work.

http://arxiv.org/abs/1302.5690
Dr Rodal, Frobnicat...
If you can make sense of this well done!
I'm afraid it's above me...



We discussed this paper earlier in this thread.  This Argentinean's (compatriot of Brito, Marini and Galian) coupling theory is negated by the unphysical, non-existent, effects predicted, as the author himself admits:

Quote
The weakest part of the theory seems to be that there is no clear way of preventing large gravitational effects due to the magnetic field of the Earth,

The nonlinear "fix" the author speculates with (and does not mathematically pursue) at the end of his paper is unlikely to work as such "nonlinear" messing up with General Relativity invariable ends up messing up Relativity's successful predictions and contradicting astrophysical results.

______________

PS: Note that the author writes:

Quote
Such claims were criticized by the scientific community mainly due to the proposed theoretical explanation, as Maxwell equations and Special Relativity clearly indicate that no force is possible without the emission of radiation from the cavity.

Recall that Dr. McCulloch's proposal satisfies this condition: McCulloch force is produced by Unruh radiation.
« Last Edit: 11/14/2014 07:58 PM by Rodal »

Offline Rodal

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Re: EM Drive Developments
« Reply #3231 on: 11/14/2014 08:08 PM »
This (Fernando O. Minotti) statement bears repeating:

the scientific community (universallly-accepted physics) ... Maxwell equations and Special Relativity clearly indicate that no (electromagnetic drive) force is possible without the emission of radiation from the cavity.
« Last Edit: 11/14/2014 08:11 PM by Rodal »

Offline Mulletron

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Re: EM Drive Developments
« Reply #3232 on: 11/14/2014 08:16 PM »
I went back to the Egan analysis and I note that for the heat locations he came up with for TE in particular, the direction of thrust would be opposite the measured thrust, if the measured thrust were due to radiation or convection. The signs are reversed. The sloping walls are hotter than the end plates.

http://www.gregegan.net/SCIENCE/Cavity/Cavity.html
What do you think?

I didn't go looking for this. I was there looking at radiation pressure plots for use with the "transfer of momentum from the QV to dielectrics" (QV sail) approach I'm championing (as opposed to White's thrusting against something that isn't there to push on or otherwise manipulate, or trying to make virtual particles "real"), and I needed to see if Shawyer's assertions of uneven radiation pressure inside the cavity held water or not. Because if Shawyer's asymmetric radiation pressure postulate is true, this boils down to simple(not so) momentum vector addition.

Challenge your preconceptions, or they will challenge you. - Velik

Offline Mulletron

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Re: EM Drive Developments
« Reply #3233 on: 11/14/2014 08:18 PM »
This (Fernando O. Minotti) statement bears repeating:

the scientific community (universallly-accepted physics) ... Maxwell equations and Special Relativity clearly indicate that no (electromagnetic drive) force is possible without the emission of radiation from the cavity.

I'm not championing Minotti's paper, just posting it. I'm full QV and thermal all the way baby! Those are the only ways I know of to conserve momentum.
« Last Edit: 11/14/2014 08:20 PM by Mulletron »
Challenge your preconceptions, or they will challenge you. - Velik

Offline Ron Stahl

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Re: EM Drive Developments
« Reply #3234 on: 11/14/2014 08:23 PM »
QV does not conserve momentum.  This is why, in the paper, Sonny specifically calls this a violation of conservation.  M-E conserves momentum.

Offline Mulletron

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Re: EM Drive Developments
« Reply #3235 on: 11/14/2014 08:26 PM »
It does the way I'm approaching it.
Challenge your preconceptions, or they will challenge you. - Velik

Offline IslandPlaya

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Re: EM Drive Developments
« Reply #3236 on: 11/14/2014 08:38 PM »
Well...
What is one to make of all this?
Does anyone know about the status/existence of ongoing experiments?
Homebrew setups seem perhaps able with the knowledge on this thread to be able to answer lots of questions. However I do not have a garage.
Anyone with an idea what the next step will be?
Thank you for answering about http://arxiv.org/abs/1302.5690
How about my broader question?

Offline Rodal

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Re: EM Drive Developments
« Reply #3237 on: 11/14/2014 09:09 PM »
Well...
What is one to make of all this?
Does anyone know about the status/existence of ongoing experiments?
Homebrew setups seem perhaps able with the knowledge on this thread to be able to answer lots of questions. However I do not have a garage.
Anyone with an idea what the next step will be?
Thank you for answering about http://arxiv.org/abs/1302.5690
How about my broader question?
This is what I recall:

1) The "Anomalous..." paper ends with "The current plan is to support an IV&V test campaign at the (NASA) Glenn Research Center (GRC) using their low thrust torsion pendulum followed by a repeat campaign at the Jet Propulsion Laboratory (JPL) using their low thrust torsion pendulum. The Johns Hopkins University Applied Physics Laboratory has also expressed an interest in performing a Cavendish Balance style test with the IV&V shipset."

2) At the NASA Ames August conference Dr. White states that one of his future steps is to measure the quantum vacuum wake left by the EM Drive by positioning another EM Drive behind it to measure the wake. 

3) Dr. White also stated that he is planning to conduct measurements with the truncated cone pointing up and also pointing down, to verify that the measured force is null under those orientations.

4) Dr. White also stated that he is planning to conduct tests in a vacuum.

Offline IslandPlaya

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Re: EM Drive Developments
« Reply #3238 on: 11/14/2014 09:11 PM »
Awesome Dr Rodal... Just what I asked, thank you.
Now,
Is this enough? Results when? Still DIY job could provide data....

Offline Rodal

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Re: EM Drive Developments
« Reply #3239 on: 11/14/2014 09:15 PM »
I went back to the Egan analysis and I note that for the heat locations he came up with for TE in particular, the direction of thrust would be opposite the measured thrust, if the measured thrust were due to radiation or convection. The signs are reversed. The sloping walls are hotter than the end plates.

http://www.gregegan.net/SCIENCE/Cavity/Cavity.html
What do you think?
...


1) Greg Egan does not show (in his plots) the Axial Magnetic field for the TE (transverse electric) modes.  Did he compute it?  Why doesn't he show it? 




Eagleworks computed the axial magnetic field and does show it (see attached picture below)

2) Consistent with #1 above, Greg Egan does not discuss the axial magnetic field heating of the ends (by eddy currents produced by the changing alternating magnetic field), in his discussion of the transverse electric mode heating.  Greg Egan wrote " for the TM modes we need to subtract the tension on the walls due to the Coulomb force acting on the charge distribution induced by the electric field meeting the walls" but for the TE modes Egan does not seem to have similarly taken into account eddy-current heating of the ends produced by the axial magnetic field perpendicular to the ends.

3) Consistent with #1 and #2 above Greg Egan shows the heated areas in TE and TM modes by the TRANSVERSE fields, but shows no heating from the axial field.



This seems wrong to me.  I expect much more significant heating from eddy currents produced by the axial magnetic field (not taken into account by Egan) than heating of the cone's round wall by the electric field which never contacts the round walls (Egan admits this, so he computes the heating as a result of the energy density instead).  This seems a wrong way to compute the heat.

4) Greg Egan considered hemispherical ends instead of the flat ends that the actual EM Drive truncated cone and the Shayer demonstrator. experimental and flight demos have.  Greg Egan does not discuss the difference caused by this assumption except that he adopted this assumption in order to obtain a closed-form solution.


Electric Field (red)

Magnetic Field (blue)

COMSOL FE solutions by Eagleworks for TE mode of truncated cone
« Last Edit: 11/14/2014 11:38 PM by Rodal »

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