Author Topic: EM Drive Developments - related to space flight applications - Thread 2  (Read 2098284 times)

Offline zlspradlin

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Like most here I'm fascinated and intrigued. However, I'm terrible at this type of math and better at making things. The device seems kind of simple on the surface, but I must assume I'm missing something (many things).

Have any science hobbyists built their own machine yet? I can't imagine that only three people have done this so far, and I'm working with a peer to design our own and build it this summer.

I'm still reading and re-reading this thread, and I'm not too many pages into it. So if someone has posted their experiments I'm sure I'll run across them sooner or later, but if anyone knows of any build logs or hobbyists making a drive I'd love to see what they did and how it worked.

I do have a question for those who may know, what do you think is the biggest hurdle to building a functioning EM Drive?
« Last Edit: 05/06/2015 03:42 PM by zlspradlin »

Like most here I'm fascinated and intrigued. However, I'm terrible at this type of math and better at making things. The device seems kind of simple on the surface, but I must assume I'm missing something (many things).

Have any science hobbyists built their own machine yet? I can't imagine that only three people have done this so far, and I'm working with a peer to design our own and build it this summer.

I'm still reading and re-reading this thread, and I'm not too many pages into it. So if someone has posted their experiments I'm sure I'll run across them sooner or later, but if anyone knows of any build logs or hobbyists making a drive I'd love to see what they did and how it worked.

I do have a question for those who may know, what do you think is the biggest hurdle to building a functioning EM Drive?
How about some open source design? openscad has been mentioned before. We could put the STL files on the wiki.

Offline TheTraveller

Like most here I'm fascinated and intrigued. However, I'm terrible at this type of math and better at making things. The device seems kind of simple on the surface, but I must assume I'm missing something (many things).

Have any science hobbyists built their own machine yet? I can't imagine that only three people have done this so far, and I'm working with a peer to design our own and build it this summer.

I'm still reading and re-reading this thread, and I'm not too many pages into it. So if someone has posted their experiments I'm sure I'll run across them sooner or later, but if anyone knows of any build logs or hobbyists making a drive I'd love to see what they did and how it worked.

I do have a question for those who may know, what do you think is the biggest hurdle to building a functioning EM Drive?
DO NOT reinvent the wheel.

Follow Shawyer as close as you can.

Plenty of clues but you need to do a lot of reading.

Checkout Mulletron's device & photos:
https://drive.google.com/folderview?id=0B4PCfHCM1KYoTXhSUTd5ZDN2WnM&usp=sharing

Mulletron has links where you can buy a cavity the same size as used by EW. PM him for details.

Read all of Mulletron & Star-Drives posts and attachments:
http://forum.nasaspaceflight.com/index.php?action=profile;area=showposts;u=45378
http://forum.nasaspaceflight.com/index.php?action=profile;area=showposts;u=2074

Be a KISS replicator (Keep It Simple Stupid)

Read the Wiki:
http://emdrive.echothis.com/index.php/Main_Page

I'm also in the early planning stage of replicating the 1st Shawyer test rig and cavity. Will put up a log, photos & drawings as I progress.

Good luck
"As for me, I am tormented with an everlasting itch for things remote. I love to sail forbidden seas.
Herman Melville, Moby Dick

Offline LasJayhawk

...

I do have a question for those who may know, what do you think is the biggest hurdle to building a functioning EM Drive?
Funding.  :(

Offline TheTraveller

Like most here I'm fascinated and intrigued. However, I'm terrible at this type of math and better at making things. The device seems kind of simple on the surface, but I must assume I'm missing something (many things).

Have any science hobbyists built their own machine yet? I can't imagine that only three people have done this so far, and I'm working with a peer to design our own and build it this summer.

I'm still reading and re-reading this thread, and I'm not too many pages into it. So if someone has posted their experiments I'm sure I'll run across them sooner or later, but if anyone knows of any build logs or hobbyists making a drive I'd love to see what they did and how it worked.

I do have a question for those who may know, what do you think is the biggest hurdle to building a functioning EM Drive?
How about some open source design? openscad has been mentioned before. We could put the STL files on the wiki.
Could add Mulletron's GDrive:
https://drive.google.com/folderview?id=0B4PCfHCM1KYoTXhSUTd5ZDN2WnM&usp=sharing
Cavity specs there plus he can point you to a cavity source/supplier if you wish to buy ready made. His photos of his progress are excellent.
"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

...

I do have a question for those who may know, what do you think is the biggest hurdle to building a functioning EM Drive?
Funding.  :(
My budget is $500. Should be enough but I have a good workshop & cabinet load of electronics. Plus a lot of self build & many hours of blood, sweat and tears.
"As for me, I am tormented with an everlasting itch for things remote. I love to sail forbidden seas.
Herman Melville, Moby Dick

Offline Rodal

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...
DO NOT reinvent the wheel.

Follow Shawyer as close as you can.

Plenty of clues but you need to do a lot of reading.

....

You are writing that in reference to Shaywer's experiments, I presume, but a number of Shawyer's prescriptions are tied to his theoretical model.  I read the paper that Shawyer sent to Mulletron, to support Shawyer's theoretical model.

I wrote a review of this paper here:  http://forum.nasaspaceflight.com/index.php?topic=36313.msg1369861#msg1369861

Showing that there is nothing in that paper (by Cullen) supporting Shawyer's theoretical model.  On the contrary, it follows the same Maxwell's equations and laws followed by Greg Egan http://gregegan.customer.netspace.net.au/SCIENCE/Cavity/Cavity.html  who concludes that the EM Drive should have no thrust force.

« Last Edit: 05/06/2015 04:17 PM by Rodal »

Offline zlspradlin

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Awesome, such fantastic responses so quickly! Thanks for the great links TheTraveller.

As for budget, I think that I might be ok in that regard, I'm afforded a few resources that a lot of hobbyists aren't, and thanks to my wife I have a great network of makers & craftsmen of all types from fine artists to industrial designers.

And I will absolutely provide STLs and anything else we create during this venture to the community. And of course I'll provide many updates whenever we get started.

I don't want to get too terribly off topic, but I just had a thought... will microwaves work with the boundary layer effect? Could a microwave rotate a Tesla Turbine?

Offline TheTraveller

...
DO NOT reinvent the wheel.

Follow Shawyer as close as you can.

Plenty of clues but you need to do a lot of reading.

....

You are writing that in reference to Shaywer's experiments, I presume, but a number of Shawyer's prescriptions are tied to his theoretical model.  I read the paper that Shawyer sent to Mulletron, to support Shawyer's theoretical model.

I wrote a review of this paper here:  http://forum.nasaspaceflight.com/index.php?topic=36313.msg1369861#msg1369861

Showing that there is nothing in that paper (by Cullen) supporting Shawyer's theoretical model.  On the contrary, it follows the same Maxwell's equations and laws followed by Greg Egan http://gregegan.customer.netspace.net.au/SCIENCE/Cavity/Cavity.html  who concludes that the EM Drive should have no thrust force.

Did Shawyer send the paper by Cullen by mistake, and he meant to send another paper instead to support his theory?

Do you know of any paper supporting Shawyer's theoretical model ?
I'm an engineer that designs, builds, commissions & teaches others how to maintain what I designed and built, while being very willing to pick up a tool bag and get grease up to my arm pits to get things back working and into service.

I look at tests of stuff that are claimed to work. If they pass my gut test, I may used them to guide my replication and test process. I try to limit reinventing the wheel.

Everything I read from Shawyer about how the devices interact with / work in the physical world, supports his many & various claims & statements & builds a strong model that they do indeed work.

To settle the matter if the EM Drive works or not, for me, demands that I do a replication, as close to the work Shawyer has done as possible. Which is what I'm planning to do.
"As for me, I am tormented with an everlasting itch for things remote. I love to sail forbidden seas.
Herman Melville, Moby Dick

Offline Rodal

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...
DO NOT reinvent the wheel.

Follow Shawyer as close as you can.

Plenty of clues but you need to do a lot of reading.

....

You are writing that in reference to Shaywer's experiments, I presume, but a number of Shawyer's prescriptions are tied to his theoretical model.  I read the paper that Shawyer sent to Mulletron, to support Shawyer's theoretical model.

I wrote a review of this paper here:  http://forum.nasaspaceflight.com/index.php?topic=36313.msg1369861#msg1369861

Showing that there is nothing in that paper (by Cullen) supporting Shawyer's theoretical model.  On the contrary, it follows the same Maxwell's equations and laws followed by Greg Egan http://gregegan.customer.netspace.net.au/SCIENCE/Cavity/Cavity.html  who concludes that the EM Drive should have no thrust force.
I'm an engineer that designs, builds, commissions & teaches others how to maintain what I designed and built, while being very willing to pick up a tool bag and get grease up to my arm pits to get things back working and into service.

I look at tests of stuff that are claimed to work. If they pass my gut test, I may used them to guide my replication and test process. I try to limit reinventing the wheel.

Everything I read from Shawyer about how the devices interact with / work in the physical world, supports his many & various claims & statements & builds a strong model that they do indeed work.

To settle the matter if the EM Drive works or not, for me, demands that I do a replication, as close to the work Shawyer has done as possible. Which is what I'm planning to do.

OK, here is one practical thing that researchers can adopt, based on Cullen's paper (and 140 years since Maxwell, with people trying to perform experimental measurements of radiation pressure, which are plagued by air convection currents), to avoid getting false-positives:

It was impossible to obtain a stable baseline, even on a relatively short-term basis of a minute's duration.  This continual drifting of the baseline was found to be due to air convection currents set up by small and changing temperature gradients within the microwave waveguides.  The remedy was to reduce the air resistance of the reflecting end plate so that the convection currents would have no appreciable effect.  The reflecting end plate was replaced by a system of concentric wire rings (shown on Fig. 12 of Cullen's paper).  The rings acted as an almost perfect reflector of the electromagnetic waves but at the same time had a small effective cross-section to air currents.  NASA, Shawyer, Yang, and other EM Drive researchers would be well advised to experiment with replacing the end plates of the EM Drive with this system of concentric rings, in order to address the problem of air convection currents that has plagued radiation pressure experiments in ambient conditions ever since Maxwell 140 years ago.
« Last Edit: 05/06/2015 05:03 PM by Rodal »

Offline PaulF

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Question to all:

Has quantum tunneling been incorporated in any calculations? I read once that at least some photons will tunnel through the medium of the cavity walls. Hope this sparks something in someone's mind.

Offline TheTraveller

OK, here is one practical thing that researchers can adopt, based on Cullen's paper (and 140 years since Maxwell, with people trying to perform experimental measurements of radiation pressure, which are plagued by air convection currents), to avoid getting false data:

It was impossible to obtain a stable baseline, even on a relatively short-term basis of a minute's duration.  This continual drifting of the baseline was found to be due to air convection currents set up by small and changing temperature gradients within the microwave waveguides.  The remedy was to reduce the air resistance of the reflecting end plate so that the convection currents would have no appreciable effect.  The reflecting end plate was replaced by a system of concentric wire rings (shown on Fig. 12 of Cullen's paper).  The rings acted as an almost perfect reflector of the electromagnetic waves but at the same time had a small effective cross-section to air currents.  NASA, Shawyer, Yang, and other EM Drive researchers would be well advised to experiment with replacing the end plates of the EM Drive with this system of concentric rings, in order to address the problem of air convection currents that has plagued radiation pressure experiments in ambient conditions ever since Maxwell 140 years ago.
Thanks for the feedback.

My replication plan is to build a Teeter-Totter balance system as Shawyer used in his 1st Feasibility device tests.

Cavity will be a copper replication of the narrow band Flight Thruster, with spherical concave/convex end plates.

RF frequency control will be via multiple stub antenna internal sense feedbacks loops (as Shawyer used with his Flight Thruster, 1 RF generator not 2), multiple on device / ambient temp sensors and RF power amp current, will all data logged including variations in the reference 250g preset downward force.

If after several months and much consulting with other replicators, there is not the slightest indication of thrust from any of the replicators, then time to consider other pathways.

If significant thrust is detected, a transparent box will be built around the test device and balance rig and the test protocols repeated. If there is still significant thrust detected, discussion will proceed to obtain, at my cost, independent verification. I do believe EarthTech and other such test labs may be interested.

I feel there is enough info now available to do a series of independent tests and draw a line in the sand. Either it works or not. If the independent lab results shows thrust, it is time to "Engage" and grow well beyond this dirt ball.

Of course, assuming it works, someone needs to figure out how it works.

Full plans and BOM (Bill of Material & suppliers) will be progressively be made available over the internet.
« Last Edit: 05/06/2015 05:38 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 zlspradlin

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The concentric rings at the end plates has sparked an idea for me. Perhaps there is a "perfect" shape for these waves to create the most thrust, couldn't this be manipulated with a holographic film? Could you not pass microwaves through a hologram to reshape the waves into the most efficient form? I suppose we need to know more about how this thing actually works before we can know the best methods/shapes. This doesn't address the air currents, but could address reflecting the waves in a more efficient way.

Holograms are not inaccessible, I've made plenty of them and even took a course on lasers & holography in college. The cost of a microwave hologram, however, I've no idea.

Offline Rodal

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.....

Please see the following reference (https://www.osapublishing.org/oe/fulltext.cfm?uri=oe-17-1-34&id=175583, click "Get PDF" to download the paper for free):

It is shown that all modes run continuously from travelling waves through a transition to an evanescent  (exponentially decaying) wave region and the value of the attenuation increases as they approach the cone vertex.

A strict distinction between pure travelling waves and pure evanescent  (exponentially decaying) waves cannot be achieved for conical waveguide.

One mode after the other reaches cutoff in the tapered hollow metallic waveguide as they approach the cone vertex.


.....

Thank you Dr. Rodal for a very informative post!

I've been studying the reference you provided, to Zeng and Fan. You cannot imagine how coincidental it is, but sometimes the universe works that way. Their equations 8 thru 11, are simple enough to understand without too much difficulty. These are "effectively" the same equations that govern gravity in the Engineering model of GR I work with, which is based on the PV Model. Gravity, as a refractive index, appears as the Damping function that governs the attenuation of the wave functions, and the ZPF acts as the Driving function that keeps it all afloat at "our" relative vacuum energy level. The two are in equilibrium, in what QED calls the fluctuation-dissipation relationship, and gravity is the asymmetry between the two that occurs wherever you have matter that filters the modes. It's pretty simple and intuitive to understand, but nobody seems to get it.

You asked about the truncated cones. From an engineering perspective, if it is not truncated it will have a difficult time resonating at any mode. The convex-concave end plates would seem to be necessary to maximize energy storage as spherical harmonics. So then, what modes do we want to attenuate? That would depend on what modes we can inject that will sustain resonance. It won't resonate when the angle is increased too much, but if we have attenuation factor equations from this paper, then I believe it can be modeled.

Getting back to the paper, based on their graphs for attenuation, it would seem a small angle is preferred. A large angle approximates a flat plate. Anything greater than pi/6 is not much better than bouncing photons off of a flat plate. However, for theta = pi/24, the attenuation is very high at much shorter wavelengths, and very high at longer wavelengths. It needs to strike a balance between energy storage and thrust at the modes available to us.

Again, gravity acts on the wave functions through the metric, transforming the (E,p) 4-vector. The metric is a refractive index. The effect on the wave function is equivalent to a Damping factor, in the damped harmonic oscillator equation. I see the attenuation factor in their plots as "similar" to that effect, acting on the microwaves in the cavity near the cut-offs. As the waves are attenuated, their momentum is absorbed as wave velocity goes to zero, just like light falling into a black hole. The result is propulsion. The bonus is that in such a space-time where the speed of light is variable, momentum conservation is dependent on the group velocity. It's not Newtonian anymore, because velocity is not a constant.

The light is being squeezed by the slowing of the group velocity, and since Energy is conserved, momentum must increase to compensate for reduced wave velocity. Another way to look at it is, photons in the waveguide "gain" an "effective mass". 

I see a lot of people arguing over photon rockets, despite the evidence that the thrust is orders of magnitude larger. No rocket nozzle is going to change that as long as the speed of light is considered to be constant, even if it captured all the energy from all the reflections produced. In order to get the thrust values they are seeing you must consider the reduction in wave velocity inside the waveguide, and that attenuation is asymmetrical, just like it is in a gravitational field.

Thanks again, for some very interesting new information.

Best Regards,
Todd D.

in the following quotation

Quote
Getting back to the paper, based on their graphs for attenuation, it would seem a small angle is preferred. A large angle approximates a flat plate. Anything greater than pi/6 is not much better than bouncing photons off of a flat plate. However, for theta = pi/24, the attenuation is very high at much shorter wavelengths, and very high at longer wavelengths. It needs to strike a balance between energy storage and thrust at the modes available to us.

Concerning Fig. 2 in the reference,  the attenuation is a very nonlinear function of kr.  For large kr (kr>20) the attenuation is small and it is also independent of the cone angle.

For small values of kr, the attenuation rapidly increases.  As you state,  for theta = pi/24, the attenuation is very high at much shorter wavelengths, and very high at longer wavelengths. 

Unfortunately, Pi/24 is the smallest angle for which they calculate the eigenvalues: there is no data shown for cone angles smaller than Pi/24.

Pi/24 = 7.5 degrees

Now, examining the following cone angles for the experiments:

Example (and geometry)                    { Tan[thetaw],thetaw (degrees) }

Shawyer Experimental                        {0.104019,   5.93851}
Shawyer Fligth Thruster                      {0.19086,   10.8055}
Shawyer Demo                                   {0.219054, 12.3557}
NASA Eagleworks frustum                   {0.263889, 14.7827}
Egan's example                                  {0.36397 ,  20}
Prof. Juan Yang  (2014)                      {0.4538,     24.4 }
Shawyer Superconducting 2014          {0.7002,     35}

It would appear that the optimum geometries were the Shawyer Experimental  and the Shawyer Fligth Thruster designs, that bracket that value (7.5 degrees) for the cone angle.

The next cone angle, examined by the authors was Pi/12 = 15 degrees, which is very close to the angle of NASA's  truncated cone.  This would show that NASA's truncated cone, Prof. Yang's and the new Superconducting design by Shawyer are non-optimal, and that Shawyer has actually been increasing the cone angle too much, if your theory would explain the measured thrust.




Concerning the statement

Quote
I see the attenuation factor in their plots as "similar" to that effect, acting on the microwaves in the cavity near the cut-offs. As the waves are attenuated, their momentum is absorbed as wave velocity goes to zero, just like light falling into a black hole. The result is propulsion.


Concerning light falling into a Black Hole, have you seen McCulloch's explanation, based on Unruh radiation ?


http://www.ptep-online.com/index_files/2015/PP-40-15.PDF

http://physicsfromtheedge.blogspot.com/2015/04/light-in-box-emdrive.html

http://physicsfromtheedge.blogspot.com/2015/03/one-wave-approximation-of-mihsc.html

http://physicsfromtheedge.blogspot.com/2015/02/mihsc-vs-emdrive-data-3d.html

http://physicsfromtheedge.blogspot.com/2014/10/mihsc-vs-emdrive-updated-table.html


« Last Edit: 05/06/2015 06:37 PM by Rodal »

Offline zen-in

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Wired has a piece today on the em-drive.   Sorry I can't quote the title; that would be too disruptive.   

http://www.wired.com/2015/05/nasa-warp-drive-yeah-still-poppycock/

Offline WarpTech

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...
DO NOT reinvent the wheel.

Follow Shawyer as close as you can.

Plenty of clues but you need to do a lot of reading.

....

You are writing that in reference to Shaywer's experiments, I presume, but a number of Shawyer's prescriptions are tied to his theoretical model.  I read the paper that Shawyer sent to Mulletron, to support Shawyer's theoretical model.

I wrote a review of this paper here:  http://forum.nasaspaceflight.com/index.php?topic=36313.msg1369861#msg1369861

Showing that there is nothing in that paper (by Cullen) supporting Shawyer's theoretical model.  On the contrary, it follows the same Maxwell's equations and laws followed by Greg Egan http://gregegan.customer.netspace.net.au/SCIENCE/Cavity/Cavity.html  who concludes that the EM Drive should have no thrust force.

The conclusions of Egan are correct when only considering radiation pressure at wavelength's that are short compared to the cut-off modes. They are incorrect because he did not take into consideration the variable speed of light inside the waveguide for wavelengths close to the cut-off modes. He used eps0 and mu0 as the permittivity and permeability of free vacuum in all his calculations of energy density and force. That is an error!

The space inside the waveguide is not free vacuum, it is constrained by the waveguide. Near the cut-ff modes, his calculations are invalidated because the speed of light is not the same throughout the cavity.

Best Regards,
Todd D.

Offline Rodal

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...
DO NOT reinvent the wheel.

Follow Shawyer as close as you can.

Plenty of clues but you need to do a lot of reading.

....

You are writing that in reference to Shaywer's experiments, I presume, but a number of Shawyer's prescriptions are tied to his theoretical model.  I read the paper that Shawyer sent to Mulletron, to support Shawyer's theoretical model.

I wrote a review of this paper here:  http://forum.nasaspaceflight.com/index.php?topic=36313.msg1369861#msg1369861

Showing that there is nothing in that paper (by Cullen) supporting Shawyer's theoretical model.  On the contrary, it follows the same Maxwell's equations and laws followed by Greg Egan http://gregegan.customer.netspace.net.au/SCIENCE/Cavity/Cavity.html  who concludes that the EM Drive should have no thrust force.

The conclusions of Egan are correct when only considering radiation pressure at wavelength's that are short compared to the cut-off modes. They are incorrect because he did not take into consideration the variable speed of light inside the waveguide for wavelengths close to the cut-off modes. He used eps0 and mu0 as the permittivity and permeability of free vacuum in all his calculations of energy density and force. That is an error!

The space inside the waveguide is not free vacuum, it is constrained by the waveguide. Near the cut-ff modes, his calculations are invalidated because the speed of light is not the same throughout the cavity.

Best Regards,
Todd D.

There is a better way to state it.  There is nothing mathematically incorrect in Greg Egan's analysis.  Egan's analysis is a restatement of well-known exact solutions to the truncated cone (going back to the 1930's).
The validity of these solutions have been confirmed during the last 80 years again and again, and they are confirmed again by the COMSOL FEA analysis and the frequencies and mode shapes measured at NASA Eagleworks.

As an example, the mathematical solution for a plane wave is exact.  One may say that anyone using a plane wave solution is not accurately representing nature because there cannot be plane waves in nature (since they extend to infinity).  Similarly, one can state that Greg Egan is using an approximation that is valid to calculate frequencies and mode shapes but perhaps not for calculating microNewton level thrust forces.

The correct statement is that any solution solely based on Maxwell's equations (like Greg Egan's analysis) predicts no thrust, and that therefore the measurements at NASA Eagleworks are due to something else not addressed by Maxwell's equations.

Todd, your explanation uses General Relativity and the Quantum Vacuum, which are explicitly not addresed by Greg Egan.  His solution is still mathematically exact (solution of Maxwell's equations), it may just not be representing the actual physical tests. Either because the tests are an artifact or because they represent some form of propulsion that may be explained by your model or other alternative models.

On the other hand what is mathematically incorrect would be to state that a solution solely based on Maxwell's equation and special relativity (without invoking GR, or the QV, or something else) can predict a thrust in a closed cavity: that is plainly mathematically incorrect.  Something else is needed besides Maxwell's equations and special relativity.

I hope yours (or another theory) succeeds in explaining the measurements as something that can be used for space propulsion, or that it is an artifact.  But the experimental measurements cannot be explained solely based on Maxwell's equations and special relativity.

 :)

Quote from: Von Neumann
The sciences do not try to explain, they hardly even try to interpret, they mainly make models. By a model is meant a mathematical construct which, with the addition of certain verbal interpretations, describes observed phenomena. The justification of such a mathematical construct is solely and precisely that it is expected to work.

« Last Edit: 05/06/2015 07:11 PM by Rodal »

Offline TheTraveller

...
DO NOT reinvent the wheel.

Follow Shawyer as close as you can.

Plenty of clues but you need to do a lot of reading.

....

You are writing that in reference to Shaywer's experiments, I presume, but a number of Shawyer's prescriptions are tied to his theoretical model.  I read the paper that Shawyer sent to Mulletron, to support Shawyer's theoretical model.

I wrote a review of this paper here:  http://forum.nasaspaceflight.com/index.php?topic=36313.msg1369861#msg1369861

Showing that there is nothing in that paper (by Cullen) supporting Shawyer's theoretical model.  On the contrary, it follows the same Maxwell's equations and laws followed by Greg Egan http://gregegan.customer.netspace.net.au/SCIENCE/Cavity/Cavity.html  who concludes that the EM Drive should have no thrust force.
I did read your review that there should be no thrust. But there seems to be thrust, of a level and direction which agrees with Shawyer's theory. Which is why the Shawyer and Chinese thrust claims need to be experimentally verified or not.

I believe there is enough data in the public domain to experimentally replicate their test setups, cavity designs and RF generation / feed methods, starting with the RF narrow band, spherical end plate Flight Thruster, feed via coax, which I plan to replicate in copper and if necessary in Alumininum.

EW is said to be replicating another cavity design, which I believe is Alumininum based, has flat end plates and is planning to blast it with wide band magnetron RF via a waveguide. Is that correct?
"As for me, I am tormented with an everlasting itch for things remote. I love to sail forbidden seas.
Herman Melville, Moby Dick

Offline Rodal

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...
DO NOT reinvent the wheel.

Follow Shawyer as close as you can.

Plenty of clues but you need to do a lot of reading.

....

You are writing that in reference to Shaywer's experiments, I presume, but a number of Shawyer's prescriptions are tied to his theoretical model.  I read the paper that Shawyer sent to Mulletron, to support Shawyer's theoretical model.

I wrote a review of this paper here:  http://forum.nasaspaceflight.com/index.php?topic=36313.msg1369861#msg1369861

Showing that there is nothing in that paper (by Cullen) supporting Shawyer's theoretical model.  On the contrary, it follows the same Maxwell's equations and laws followed by Greg Egan http://gregegan.customer.netspace.net.au/SCIENCE/Cavity/Cavity.html  who concludes that the EM Drive should have no thrust force.
I did read your review that there should be no thrust. But there seems to be thrust, of a level and direction which agrees with Shawyer's theory. Which is why the Shawyer and Chinese thrust claims need to be experimentally verified or not.

I believe there is enough data in the public domain to experimentally replicate their test setups, cavity designs and RF generation / feed methods, starting with the RF narrow band, spherical end plate Flight Thruster, feed via coax, which I plan to replicate in copper and if necessary in Alumininum.

...

No, my review never states that there should be no thrust in the experimental results. 

My review instead states (and shows, carefully, point by point) that the reference given by Shawyer to support his theoretical model, does NOT support his model at all.

Therefore I do not understand why Shawyer references Cullen's paper.

As a reductio ad absurdum, it would be almost like Shawyer referencing Greg Egan, and sending Greg Egan's analysis as support for Shawyer's theoretical explanation.
« Last Edit: 05/06/2015 07:29 PM by Rodal »

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Out of interest have any of Eagleworks results appeared on arXiv?

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