Author Topic: EM Drive Developments - related to space flight applications - Thread 2  (Read 2099708 times)

Offline TheTraveller

@TheTraveller - you are nothing if not pragmatic :D

Quote
Shawyer & Chinese conic frustums provide thrust that matches their equations predictions.
Please cite an example set of numbers that instantiates this:
1. frustum big diameter & curvature
2. frustum small diameter & curvature
3. frustum vertical height
4. operating frequency
5. predicted thrust
6. measured thrust

Can you do this?
(no dielectric please, and preferably flat ends)

Before I came on board, no one understood the Df equation, nor guide wavelength nor cutoff wavelength as used by Shawyer. It was all about classic physics and the tools derived from them showing NO THRUST will be generated. The pathway seemed to be:

If there is thrust then as our tools say no thrust, there must be new physics involved, despite Shawyer and the Chinese saying there is thrust and it can be predicted by a non classical use of the existing physics.

Instead of trying to understand what Shawyer and the Chinese are saying about how they successfully use existing physics to predict the thrust, the forum goes off to left field and dreams up ways to not need to try to understand what Shawyer and the Chinese are saying.

Which leave me, who wishes to build a Flight Thruster and have an excel spreadsheet that predicts thrust as the dimensions and frequency are varied in right field, far away from most on this thread who have chosen to play in left field and think what I'm doing is, well a sign of madness, as I will not Hi Five the desire to play in left field and ignore what Shawyer and the Chinese have shared.

Bottom line is both Shawyer and the Chinese have measured thrust on dozens of devices and that thrust is predictable from their equations. Yet those equations are totally ignored. So who is mad? Those who ignore what Shawyer and the Chinese have shared or those who ignore their results and the predictive equation they share?

For me, the pathway is to continue to talk with Shawyer, as he gives me a pat on the head and offers another bread crumb and to continue to put together a spreadsheet that allows me to calc Df and frustum length as per Shawyers shared info and equations so as to get optimal thrust at my desired operational wavelength.

With the greatest respect to others on the forum, why should I engage with equations that predict no thrust as they give me NO feedback to produce an excel spreadsheet to model what I'm attempting to do.

It is ALL about the THRUST (non dielectric) and how to model it so as I change big end and small end diameters, the Df calcs properly and from that, the length calcs properly as per the internal effective wavelength.
« Last Edit: 05/23/2015 08:10 AM by TheTraveller »
"As for me, I am tormented with an everlasting itch for things remote. I love to sail forbidden seas.
Herman Melville, Moby Dick

Offline TheTraveller

???
Starting to wonder if I'm reading an updated version of Hansel and Gretel.... with all those bread crumb references ?

Seriously TheTraveler, I'd rather see you start building your setup instead of getting entangled in endless debates about R.Shawyer's merits.
With your insights and eye for detail, I'm sure your test will be much more informative then the crude (but very interesting/promising) test Iullian made.

So please man, stop digging trenches and go for what you originally planned to do : build a working model...

All this ping-pong stuff about what or what not Shawyer said/did/might have said/ could have meant...sigh... you should not take the criticism on Shawyer's texts as personal "insult"(maybe a big word).... it is all a distraction...let it go...and focus again...

You started so well... :-\

TheTraveller is doing his due-dilligence to get the dimensions correct - otherwise there will be no thrust (or there will be by just dumb luck). Verification against what has been done before is all part of the process.  It's engineering and art, and I'm very impressed by what he's doing.

Comments appreciated.

Another bread crumb is Shawyer's mention in this EM Drive patent and in several of his papers that he excited the frustum at TM01. Originally not knowing what that meant, I googled it and found:

1) TM = the frustum is excited in a way to obtain, inside the frustum, a transverse magnetic field and a electric field that propagates from end plat to end plate. If you excite at the axial centre of the frustum, the e field is centered in the middle of the frustum.

2) 01 = there is a 1/2 wavelength that resonates between the 2 end plates.

I really don't think that going deeper is needed.
"As for me, I am tormented with an everlasting itch for things remote. I love to sail forbidden seas.
Herman Melville, Moby Dick

Offline Left Field

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@TheTraveller - you are nothing if not pragmatic :D

Quote
Shawyer & Chinese conic frustums provide thrust that matches their equations predictions.
Please cite an example set of numbers that instantiates this:
1. frustum big diameter & curvature
2. frustum small diameter & curvature
3. frustum vertical height
4. operating frequency
5. predicted thrust
6. measured thrust

Can you do this?
(no dielectric please, and preferably flat ends)

Before I came on board, no one understood the Df equation, nor guide wavelength nor cutoff wavelength as used by Shawyer. It was all about classic physics and the tools derived from them showing NO THRUST will be generated. The pathway seemed to be:

If there is thrust then as our tools say no thrust, there must be new physics involved, despite Shawyer and the Chinese saying there is thrust and it can be predicted by a non classical use of the existing physics.

Instead of trying to understand what Shawyer and the Chinese are saying about how they successfully use existing physics to predict the thrust, the forum goes off to left field and dreams up ways to not need to try to understand what Shawyer and the Chinese are saying.

Which leave me, who wishes to build a Flight Thruster and have an excel spreadsheet that predicts thrust as the dimensions and frequency are varied in right field, far away from most on this thread who have chosen to play in left field and think what I'm doing is, well a sign of madness, as I will not Hi Five the desire to play in left field and ignore what Shawyer and the Chinese have shared.

Bottom line is both Shawyer and the Chinese have measured thrust on dozens of devices and that thrust is predictable from their equations. Yet those equations are totally ignored. So who is mad? Those who ignore what Shawyer and the Chinese have shared or those who ignore their results and the predictive equation they share?

For me, the pathway is to continue to talk with Shawyer, as he gives me a pat on the head and offers another bread crumb and to continue to put together a spreadsheet that allows me to calc Df and frustum length as per Shawyers shared info and equations so as to get optimal thrust at my desired operational wavelength.

With the greatest respect to others on the forum, why should I engage with equations that predict no thrust as they give me NO feedback to produce an excel spreadsheet to model what I'm attempting to do.

It is ALL about the THRUST (non dielectric) and how to model it so as I change big end and small end diameters, the Df calcs properly and from that, the length calcs properly as per the internal effective wavelength.
You need to reverse the polarity captain! Unconventional thinking is definitely left field - hence my monicker.

Offline Chris Bergin

Right, that's over a million views for this thread. Let's consider a new, fresh, centralized thread, lead by a post to the relevant links here and with some ground rules.

That'll provide focus (long threads tend to lose that), updates (if and when they arrive) and discussion (which is the meat on the bones of any thread) - moderated to keep any silly posts out of the debate (this site's forum will always put signal before noise). It'll also avoid the potential of lots of threads on this, which is where the conversation becomes diluted and threatens to take over a section that - which advanced - wasn't really set up to cover this subject of EM Drive (ironic, given it became a subject resulting in 1.5 million views on its related threads and a 600,000 read article).

Also, I've had two e-mails worried about folk getting overexcited about setting up their own experiments (which can be hazardous). This subject is being debated on several sites, but we can at least show some responsibility with the guidance to people visiting this site.

So, Dr. Rodal - I'll PM you later about setting this new thread up, but this post is to give a heads up to all that we're going to be efforting this over the coming days.

Offline SeeShells

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You got it  :)
Yes, if the thrust is real (and the avalanche of replications like Iulian's make it feel more and more real) it looks to be produced by an uncoupled process.

Uncoupled processes are not uncommon, as you know actually more physical problems involve uncoupled physics or negligible amounts of coupling.  Strongly coupled processes are more unusual.  For example, most heat-transfer  effects on structures are essentially uncoupled: thermal expansion, thermal stress, etc.  The coupling in the equations of thermoelasticity is usually negligible.  One can solve Fourier's equations separately, figure out the temperature distribution and from the temperature distribution calculate a thermal stress analysis.  No coupling (with the exception of very thin shells, etc.).

Notsosureofit's formula is an uncoupled formula (notsosureofit please correct me if I'm wrong).  The thrust force is dependent on the mode shapes.  One can first calculate the mode shapes based on standard Maxwell's equations, and from them calculate the thrust force.  I suppose that if the theory matures one can then refine it and explore different types of coupling and nonlinearities like in every theory (publish of perish  :) ) but the main effect, to first order appears uncoupled, based on the experimental frequency and mode shape data.



For comparison (stronger nonlinearity) here's an acoustic case:

http://www.zainea.com/lowresonances.htm
So many things are connected. I just finished scanning this interesting paper, not a new unknown effect (pretty pictures  8) ) and some correlations to what we're doing in harmonics and the effects they can have in a localized environment.
http://xlab.me.berkeley.edu/pdf/245.pdf
I have some reading to do and some coffee to wash it all down with.

Offline Notsosureofit

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So many things are connected. I just finished scanning this interesting paper, not a new unknown effect (pretty pictures  8) ) and some correlations to what we're doing in harmonics and the effects they can have in a localized environment.
http://xlab.me.berkeley.edu/pdf/245.pdf
I have some reading to do and some coffee to wash it all down with.

Great find !  Yes, that's an acoustic analog.

"As pointed out in previous studies, the self-bending beam represents an
envelope of rays and there exists a singular gradient mapping between the ray
surface (wavefront) and the self-bending beams (caustics)23. As shown in Fig. 6, the
geometric representation of such a condition is that all the rays forming a caustic
are tangents of the caustic trajectory. As the geometric wavefront is always
perpendicular to the rays, one can construct a unique wavefront family from the
tangential rays of the caustic trajectory. Once the wavefront is determined, the
phase map on a planar source plane can be generated by tracing each point on the
wavefront to the source plane along the ray and calculating the phase retardation28.
To formulate our recipe, let us consider a phased array located in x–z plane
emitting acoustic rays according to a certain phase profile j(x), as illustrated in
Fig. 6. During the propagation along the positive z axis, the rays construct a desired
self-bending wave packet at x f(z), where the single-valued function f depicts an
arbitrary convex curve. Next we shall use Legendre transformations to construct
the geometric wavefront from a preset beam trajectory."

  In the EM tapered cavity case the phase map (3D this time) is the dispersion profile of the cavity interior.  To get the expected curvature, we must imagine the cavity structure to be massless.  The force arises as the reaction to the (ordinary) inertial mass of the real cavity structure.  That's it in a nutshell.

  To further the analogy, each point in the cavity volume can be considered as a "loudspeaker" w/ a determined amplitude and phase.  (hope that helps to visualize)

As an aside, they only need use the first of the three acoustic wave equations here as the viscous and thermal transport coefficients are small in this case.
« Last Edit: 05/23/2015 01:41 PM by Notsosureofit »

Offline StrongGR

...

By contrast, in a closed cavity, there is a reflection at the walls, there is nothing coming out (unless we consider quantum tunneling, or heat dissipation like radiative heat transfer in a vacuum or convective heat transfer in air)

Or gravity maybe?

Offline Notsosureofit

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  They are making an acoustic hologram.

Great references.
« Last Edit: 05/23/2015 02:35 PM by Notsosureofit »

Offline Notsosureofit

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  They are making an acoustic hologram.
Yes, but the topology  seems to be different: the correct hologram should be of a completely enclosed cavity, while the hologram in the paper has two open holes: an entry hole and an exit hole that are not present in the EM Drive (unless one invokes radiation heat transfer, convective heat transfer, perhaps general relativity, etc.)

The topology is different.  The wave packet in the EM case has the shape and phase distribution set by the cavity.  If the cavity walls disappeared the trajectory of the wave packet would curve in 4-space (accelerate).  It can't do that because the cavity is still there and has much more mass-equivalent than the wavepacket, so all you see is the reaction force.
« Last Edit: 05/23/2015 02:42 PM by Notsosureofit »

Offline Rodal

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  They are making an acoustic hologram.
Yes, but the topology  seems to be different: the correct hologram should be of a completely enclosed cavity, while the hologram in the paper has two open holes: an entry hole and an exit hole that are not present in the EM Drive (unless one invokes radiation heat transfer, convective heat transfer, perhaps general relativity, etc.)

The topology is different.  The wave packet in the EM case has the shape and phase distribution set by the cavity.  If the cavity walls disappeared the trajectory of the wave packet would curve.  It can't do that because the cavity is still there and has much more mass-equivalant than the wavepacket, so all you see is the reaction force.
OK, I would have to work out the math to convince myself that the "walls dissapeared".  If they dissapeared we are in agreement. But to get there I need a proof, as you said  :)

Offline Notsosureofit

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  They are making an acoustic hologram.
Yes, but the topology  seems to be different: the correct hologram should be of a completely enclosed cavity, while the hologram in the paper has two open holes: an entry hole and an exit hole that are not present in the EM Drive (unless one invokes radiation heat transfer, convective heat transfer, perhaps general relativity, etc.)

The topology is different.  The wave packet in the EM case has the shape and phase distribution set by the cavity.  If the cavity walls disappeared the trajectory of the wave packet would curve.  It can't do that because the cavity is still there and has much more mass-equivalant than the wavepacket, so all you see is the reaction force.
OK, I would have to work out the math to convince myself that the "walls dissapeared".  If they dissapeared we are in agreement. But to get there I need a proof, as you said  :)

You are still too quick for me !
4-D "curve" is acceleration.  The "holographic" representation is 3-D in the EM cavity.  The fixed plane is time.

It should be reducible to a x,y version w/ z,t in the propagation direction (?) but again the walls must disappear for it to propagate.  ??  does the Poynting vector satisfy that condition if the walls are removed ?  Probably not when I try to visualize it. ? although the standing waves are then propagating waves.  Still sounds like you need to integrate all point spherical waves over the cavity volume using their instantaneous amplitude and phase when the walls disappear.

(Sorry about thinking out loud)
« Last Edit: 05/23/2015 03:14 PM by Notsosureofit »

Offline Rodal

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...
You are still too quick for me !
4-D "curve" is acceleration.  The "holographic" representation is 3-D in the EM cavity.  The fixed plane is time.

It should be reducible to a x,y version w/ z,t in the propagation direction (?) but again the walls must disappear for it to propagate.  ??  does the Poynting vector satisfy that condition if the walls are removed ?  Probably not when I try to visualize it. ?
The only way I can see having a non-zero period-time-averaged Poynting vector in a cavity is either through a nonlinearity (example: Marco Frasca's second order nonlinearity due to GR, or van Tiggelen's 4th order nonlinearity due to magneto-chiral effect), or through an energy gradient (radiative heat transfer, etc.).

The example you gave with the "backbone curve" (as it is known in the literature, where one has a nonlinear spring) is a nonlinearity.
« Last Edit: 05/23/2015 03:33 PM by Rodal »

Offline TheTraveller

@TheTraveller - you are nothing if not pragmatic :D

Quote
Shawyer & Chinese conic frustums provide thrust that matches their equations predictions.
Please cite an example set of numbers that instantiates this:
1. frustum big diameter & curvature
2. frustum small diameter & curvature
3. frustum vertical height
4. operating frequency
5. predicted thrust
6. measured thrust

Can you do this?
(no dielectric please, and preferably flat ends)

Before I came on board, no one understood the Df equation, nor guide wavelength nor cutoff wavelength as used by Shawyer. It was all about classic physics and the tools derived from them showing NO THRUST will be generated. The pathway seemed to be:

If there is thrust then as our tools say no thrust, there must be new physics involved, despite Shawyer and the Chinese saying there is thrust and it can be predicted by a non classical use of the existing physics.

Instead of trying to understand what Shawyer and the Chinese are saying about how they successfully use existing physics to predict the thrust, the forum goes off to left field and dreams up ways to not need to try to understand what Shawyer and the Chinese are saying.

Which leave me, who wishes to build a Flight Thruster and have an excel spreadsheet that predicts thrust as the dimensions and frequency are varied in right field, far away from most on this thread who have chosen to play in left field and think what I'm doing is, well a sign of madness, as I will not Hi Five the desire to play in left field and ignore what Shawyer and the Chinese have shared.

Bottom line is both Shawyer and the Chinese have measured thrust on dozens of devices and that thrust is predictable from their equations. Yet those equations are totally ignored. So who is mad? Those who ignore what Shawyer and the Chinese have shared or those who ignore their results and the predictive equation they share?

For me, the pathway is to continue to talk with Shawyer, as he gives me a pat on the head and offers another bread crumb and to continue to put together a spreadsheet that allows me to calc Df and frustum length as per Shawyers shared info and equations so as to get optimal thrust at my desired operational wavelength.

With the greatest respect to others on the forum, why should I engage with equations that predict no thrust as they give me NO feedback to produce an excel spreadsheet to model what I'm attempting to do.

It is ALL about the THRUST (non dielectric) and how to model it so as I change big end and small end diameters, the Df calcs properly and from that, the length calcs properly as per the internal effective wavelength.
You need to reverse the polarity captain! Unconventional thinking is definitely left field - hence my monicker.

I follow Shawyer.

No need to reverse anything. His equations and explanations cover how this works. He uses conventional physics, just applied a bit different to normal.
"As for me, I am tormented with an everlasting itch for things remote. I love to sail forbidden seas.
Herman Melville, Moby Dick

Offline Notsosureofit

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You are still too quick for me !
4-D "curve" is acceleration.  The "holographic" representation is 3-D in the EM cavity.  The fixed plane is time.

It should be reducible to a x,y version w/ z,t in the propagation direction (?) but again the walls must disappear for it to propagate.  ??  does the Poynting vector satisfy that condition if the walls are removed ?  Probably not when I try to visualize it. ?
The only way I can see having a non-zero Poynting vector in a cavity is either through a nonlinearity (example: Marco Frasca's second order nonlinearity due to GR, or van Tiggelen's 4th order nonlinearity due to magneto-chiral effect), or through an energy gradient (radiative heat transfer, etc.)

Of course, if the Poynting vector stays zero then momentum is conserved.  Is that the case in a self-accelerating wavefunction ?  I havn't seen it explicitly mentioned but they do claim CoM.

Offline Rodal

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You are still too quick for me !
4-D "curve" is acceleration.  The "holographic" representation is 3-D in the EM cavity.  The fixed plane is time.

It should be reducible to a x,y version w/ z,t in the propagation direction (?) but again the walls must disappear for it to propagate.  ??  does the Poynting vector satisfy that condition if the walls are removed ?  Probably not when I try to visualize it. ?
The only way I can see having a non-zero Poynting vector in a cavity is either through a nonlinearity (example: Marco Frasca's second order nonlinearity due to GR, or van Tiggelen's 4th order nonlinearity due to magneto-chiral effect), or through an energy gradient (radiative heat transfer, etc.)

Of course, if the Poynting vector stays zero then momentum is conserved.  Is that the case in a self-accelerating wavefunction ?  I havn't seen it explicitly mentioned but they do claim CoM.
To be specific, let's point out that we are talking about the time-average (over an integer number of periods) of the Poynting vector being zero, as the Poynting vector itself is a non-zero harmonic function of time even as a solution of Maxwell's equations (the Poynting vector in that case having twice the frequency of the electromagnetic field frequency).
« Last Edit: 05/23/2015 03:26 PM by Rodal »

Offline Notsosureofit

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Yes, only the "disappearance" of the wall for mathematical reasons would be instantaneous.
« Last Edit: 05/23/2015 03:31 PM by Notsosureofit »

Offline SeeShells

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  They are making an acoustic hologram.
Yes, but the topology  seems to be different: the correct hologram should be of a completely enclosed cavity, while the hologram in the paper has two open holes: an entry hole and an exit hole that are not present in the EM Drive (unless one invokes radiation heat transfer, convective heat transfer, perhaps general relativity, etc.)

The topology is different.  The wave packet in the EM case has the shape and phase distribution set by the cavity.  If the cavity walls disappeared the trajectory of the wave packet would curve.  It can't do that because the cavity is still there and has much more mass-equivalant than the wavepacket, so all you see is the reaction force.
OK, I would have to work out the math to convince myself that the "walls dissapeared".  If they dissapeared we are in agreement. But to get there I need a proof, as you said  :)

You are still too quick for me !
4-D "curve" is acceleration.  The "holographic" representation is 3-D in the EM cavity.

Consider this, let's turn on the acoustic wave guide. Then close off the exit, closing off the Acoustic chamber.  The waves entering into the closed area in the chamber would be reflected back creating another set of set of interference harmonics and possibly destructive to the pattern of the first mode. But let's say I dampened the acoustic waves on the exit door, turning them into a pattern of heat? I see heat in the patterns of the thermal images even though they are RF dissipation in the copper.
So tell me, what is the difference in a system thinking this way? We still maintain the desired mode, whether acoustic or em wave.
Notsosureofit I think we are seeing the same thing but you have a much more eloquent way of stating it, I'm more nuts... well and bolts kinda gal.

Offline Notsosureofit

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Consider this, let's turn on the acoustic wave guide. Then close off the exit, closing off the Acoustic chamber.  The waves entering into the closed area in the chamber would be reflected back creating another set of set of interference harmonics and possibly destructive to the pattern of the first mode. But let's say I dampened the acoustic waves on the exit door, turning them into a pattern of heat? I see heat in the patterns of the thermal images even though they are RF dissipation in the copper.
So tell me, what is the difference in a system thinking this way? We still maintain the desired mode, whether acoustic or em wave.
Notsosureofit I think we are seeing the same thing but you have a much more eloquent way of stating it, I'm more nuts... well and bolts kinda gal.

In this case we are ignoring the dissipation by inputting constant power to make up for it.  The EM and (pressure) acoustic systems are similar in many ways.

When I try to do a thermodynamic calculation all bets are off.
« Last Edit: 05/23/2015 03:47 PM by Notsosureofit »

Offline TheTraveller

By contrast, in a closed cavity, there is a reflection at the walls, there is nothing coming out (unless we consider quantum tunneling, or heat dissipation like radiative heat transfer in a vacuum or convective heat transfer in air)

Yes nothing is expelled from the frustum.

However in both the Shawyer and Chinese test data thrust is generated, which should say to you that what Shawyer is saying about his theory and what the Chinese are saying about their theory is correct and your and other conventional application of theory is not correct.

I refer to Feynman:


"If it [theory] disagrees with experiment it is wrong."

Yet the trust of this forum seems to be to reject Shawyer and Chinese theory, which matches their experimental results, and seek some new theory outside physics when all that is needed is to listen to Shawyer and the Chinese and apply existing theory in a non conventional way.

For an engineer, seeking to model in excel what is happening as dimensions and frequency are varied, the blue sky theories on this forum provide no help, as none can take frustum dimensions and frequency and predict thrust per power applied. In fact most say there is NO THRUST.

However Shawyer's theory and equations does appear to model the thrust but those equations and explanations seem to be almost universally rejected.

Which going back to Feynman, with respect, is about as unscientific as it can get. Others claiming sloppy measurement protocols are just trying to find excuses to deal with reality and avoiding needing to accept the Shawyer and Chinese applications of current theory and thrust measurements are correct.

For me I'll follow what Boyd Bushman & Paul March advised:
http://forum.nasaspaceflight.com/index.php?topic=36313.msg1356062#msg1356062

Quote
Follow the data, theory be dammed
« Last Edit: 05/23/2015 03:50 PM by TheTraveller »
"As for me, I am tormented with an everlasting itch for things remote. I love to sail forbidden seas.
Herman Melville, Moby Dick

Offline skrock

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Hi, I hope this is ok. Just found this interview with Shawyer on youtube

This thread is very interesting, still deciding what to study later on and this is inspirational stuff.
Greetings from Sweden.

/Marcus

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