Author Topic: EM Drive Developments - related to space flight applications - Thread 3  (Read 1877763 times)

Offline TheTraveller

Thks...since it early in my build, can you suggest measurements for 2.450 ghz resonance? Can change mechanicals not freq as easily...

TE013 with your big and small end diameters:

2.50GHz = length: 0.2603m
2.45GHz = length: 0.2739m
2.40GHz = length: 0.2906m

I would use 0.2603 as that puts the 2.45GHz length resonance point as being 1/2 way between the centre and the outside of the end plates. See the lower right chart (attached) which shows where the length resonance occurs (green vertical bar). That allows your frequency to wander around a bit but still stay in cavity length resonance. This is a nice feature of using flat end plates.
« Last Edit: 06/17/2015 02:07 AM by TheTraveller »
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Offline rfmwguy

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Thks...since it early in my build, can you suggest measurements for 2.450 ghz resonance? Can change mechanicals not freq as easily...

TE013 with your big and small end diameters:

2.50GHz = length: 0.2603m
2.45GHz = length: 0.2739m
2.40GHz = length: 0.2906m

Nice example of collaboration...many thanks!

Offline deltaMass

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This is probably easily debunked, but it does pertain to Conservation of Momentum.

Couple days ago, I was at a lake.  Glass calm, no waves, no current.

I loaded myself into a canoe for a little spin.  Got out into the water. Drifted to a complete or near complete halt.  Then...

while remaining seated AND hands holding on tight to the side of the canoe, I 'threw' my torso forward.  I never actually left the seat.  But the canoe did move in that direction.  I then straightened myself up (slowly) and repeated the process a few times.  Each time, the canoe would shoot forward (ok move forward at less than paddle speed) for about two yards or so...but there was never any corresponding 'back motion' when I straightened.

So...violation of CoM or something else?  And could what I was doing be used as an analogy for whatever is going on with the EM Drive?

Essentially, you are in an open system (the lake) and are relying on the friction (viscosity) of the water to hold the canoe as you come back to a full sitting position.

That said, I am gradually starting to wonder whether EM drives are operating in a similar fashion.  The issue is whether EM drives really are closed or are in fact doing something like your experiment.  The question here is what is the friction that the EM drives are using.  It could be magnetism or something related to the quantum vacuum (aka the propeller theory).  It could even be something like columbic potential..

My money, rightly or wrongly, is on something simple that is surprising.
Two words: Dean drive.

Offline TheTraveller

Thks...since it early in my build, can you suggest measurements for 2.450 ghz resonance? Can change mechanicals not freq as easily...

TE013 with your big and small end diameters:

2.50GHz = length: 0.2603m
2.45GHz = length: 0.2739m
2.40GHz = length: 0.2906m

Nice example of collaboration...many thanks!

Please review additions to that post.
"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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However, I do not see a direct connection yet between the article in Nature and the work of Igor Pikovski, about quantum decoherence to what Todd has been proposing. 

The microwave electromagnetic fields inside the EM Drive are carried by photons, which are quantum particles.  Photons are capable of displaying quantum coherence and decoherence.   The laser, superconductivity and superfluidity are examples of highly coherent quantum systems whose effects are evident at the macroscopic scale.

I know of nothing in the EM Drive experiments that has shown a state of quantum coherence, and therefore nothing that has shown that decoherence takes place in the EM Drive.  So where is the connection to the EM Drive?

Regarding Todd's papers, if he posited quantum coherence, I missed that in his papers.  My understanding is the contrary, that his emphasis is on geometric attenuation producing evanescent waves that can carry momentum.  Todd is not even looking for a super-high Q, but portrays the tug-of-war between Q storage and attenuation and evanescent waves as what could enable the EM Drive to work.

Jose,

If I were talking about gravity in atoms, their paper would be a a spot-on way to look at it. Equation's (5) & (6) are similar in form to the Zitterbewegung motion of the electron in the Dirac equation that I typically refer to. When 2 particles are coupled, they have coherent states. In a gravitational field, we have asymmetry in time.

In the case of the frustum, it is not "quantum" but the standing waves are still a coherent state, just as they are in a laser or a maser. We have 2 waves, "forward" and "backward" that are phase shifted due to the asymmetrical attenuation, i.e., asymmetrical wave velocity, guide wavelength, geometry, whatever. The two waves are out of phase and you can see in their Fig. 1c, that the phase shifted superposition has a component along the "real" Power axis, i.e, the Power Factor is not 0.

This action causes the center of mass between the two to shift. The "decoherence" they are referring to, is what I've been referring to as "constructive and destructive interference". This is the information contained in the Matrix terms they are referring to. I'm just saying it in my own Engineering-speak. If the frustum were replaced by a cylinder, this phase interference would not happen. The frustum is a nice conical-section representation of a spherically symmetric gravitational field, that only exists over a very narrow bandwidth. :)
Todd
Thank you for your explanation.  What I read in the paper by Igor Pikovski et.al. is an argument for the quantum decoherence problem: why is it that we don't see quantum behavior in macroscopic objects? What is responsible for decoherence?  They show that classical general relativity can account for the suppression of quantum behavior for macroscopic objects without introducing modi cations to quantum mechanics or to general relativity. 

 It is nice to have an explanation for quantum decoherence that resolves the correlation paradoxes of quantum theory, such as the Einstein Podolsky Rosen paradox and Schrödinger's cat. It is nice to know that decoherence can be resolved by general relativity, particular for people like me that don't like Everett's many world interpretation.

Having said that, as to how this relates to the EM Drive conservation of momentum problem, I don't yet see it.  The EM Drive could be a Maser, but none of the researchers have built it like a Maser. So to me the EM Drive as a macroscopic body, never achieves coherence.  Maybe I have to think some more about it :-)

« Last Edit: 06/17/2015 02:28 AM by Rodal »

Offline WarpTech

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 It is nice to have an explanation for quantum decoherence that resolves the correlation paradoxes of quantum theory, such as the Einstein Podolsky Rosen paradox and Schrödinger's cat. It is nice to know that decoherence can be resolved by general relativity, particular for people like me that don't like Everett's many world interpretation.

Having said that, as to how this relates to the EM Drive conservation of momentum problem, I don't yet see it.  The EM Drive could be a Maser, but none of the researchers have built it like a Maser. So to me the EM Drive as a macroscopic body, never achieves coherence.  Maybe I have to think some more about it :-)

Ahh.... What you seek is a theory of Quantum Gravity. None exists. I'm offering my engineering version of it as a way of bridging the classical and quantum behavior of electron "matter" waves. The "easiest" bridge I have found is through the Action of the wave functions. The EM field modifies the phase of the wave. The gravitational field is input through the metric tensor, when taking the product of the 4-vectors, <pu guv xv>. In a weak field approximation, it's simply adding a little bit more or less to the phase shift! There is no distinguishable way to know if the phase shift occurs due to gravity, or the EM potentials. Gauge transformations are also gravitational potential transformations. They have no effect on the local values of E or B because they differ only by a phase shift and a different coordinate speed of light of c/K.

Also, as Shell said, copper will not shield a magnetic field. I can emphasize that, by this she means a DC magnetic field. The AC field can't penetrate much beyond the skin depth. Correct? However, a DC magnetic field can pass right through it.

How about this proposal, conjecture.... that the evanescent waves are inducing persistent DC currents, precisely because their time average is not zero. The Volt-Seconds (magnetic flux) do not cancel! This allows mass to be stored as a DC offset in the current and the magnetic field. That DC offset can escape through the copper.

In fact, I know from experience when attempting to design DC to AC Inverters, it is very difficult to PREVENT DC offset from accumulating in a low impedance transformer. One must design special circuitry to control the reference and keep the oscillation in the flux density centered in the B/H curve of the transformer core. I was struggling to understand how the mass was increasing so significantly, now I understand that the stored current may be DC and the associated magnetic field, stored in the small end of the frustum and caused by the time-asymmetry of the evanescent wave's near-field induction effects. Along the walls of the frustum, the gauge potential has a divergence, offset by a change in the refractive index. This divergent field can escape and away we go!

Damn! I hope I said that right. Happy birthday to me!
Todd

EDIT: This supports my previous conjecture, that we don't need microwaves at all.
« Last Edit: 06/17/2015 04:43 AM by WarpTech »

Offline Abyss

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http://phys.org/news/2015-06-theory-reality-nonlinear-optical-metamaterials.html

Synopsis: metamaterials with negative index of refraction created in testable quantities for the first time.

Well metamaterials have been experimentally studied with negative index for more than a decade (See: http://www.sciencemag.org/content/292/5514/77) these materials are very resonant in nature so they only function in a narrow frequency region, and often for only a single polarization of light.  If something really wierd was going to happen they'd have seen it already.

It looks like in that paper they finally scaled the meta material down to optical frequencies, but negative index materials have been studied before.

For the frequencies we use with em drive we'd want the lower frequencies that have already been studied in the past.

Metamaterials are my area of research, although I don't work on negative index variants.

Offline ThinkerX

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Two words: Dean drive.

So you are arguing the EM Drive is a weird artifact then?  Or that there may actually be the proverbial 'grain of salt' to Dean's theory?

Here is another thought I had upon reading Miss Greene's initial post here a few pages back.

We have a space suited  astronaut in the cargo bay of a orbiting shuttle craft.  Cargo bay is in vacuum, but also sealed - a closed system.  Midpoint in the cargo bay walls are a series of powerful fans.  Astronaut is braced against forward bulkhead.

Astronaut fires gas gun back down center axis of the shuttle bay.  Normally, in those circumstances (weightlessness, vacuum), this would propel the shuttle craft forward...until the gas hit the far wall of the cargo bay, canceling the effect.  Except, this time, the fans in the side of the cargo bay kick to life, dispersing the gas jet at the midpoint.  The gas doesn't loose momentum, but the bulk of it strikes the sides of the cargo bay instead of the end. In that situation, the shuttle should move forward. 

Next thought I had, connected with the above:

A 'gun' firing hollow metal pellets down a long tube set inside the cargo bay.  Interior of the tube is lined with sequenced electromagnets - making it a sort of 'rail gun.'  Hence, pellets inside tube are greatly accelerated, striking the far wall with great force - outside the tube, transferring momentum.  AFTER this bounce, more powerful magnets yank the pellets sideways in different directions, while also slowing them down.  Hence, when they strike the sides, their momentum is likewise dispersed.  Yes, its fanciful.

With the EM Drive proper, though, I have another thought that keeps bugging me.  We keep talking about 'photons' - particles. Sometimes 'waves' get mentioned, and get treated as something entirely different.  But 'light' (EM Energy) is BOTH at the same time. 

Online demofsky

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This is probably easily debunked, but it does pertain to Conservation of Momentum.

Couple days ago, I was at a lake.  Glass calm, no waves, no current.

I loaded myself into a canoe for a little spin.  Got out into the water. Drifted to a complete or near complete halt.  Then...

while remaining seated AND hands holding on tight to the side of the canoe, I 'threw' my torso forward.  I never actually left the seat.  But the canoe did move in that direction.  I then straightened myself up (slowly) and repeated the process a few times.  Each time, the canoe would shoot forward (ok move forward at less than paddle speed) for about two yards or so...but there was never any corresponding 'back motion' when I straightened.

So...violation of CoM or something else?  And could what I was doing be used as an analogy for whatever is going on with the EM Drive?

Essentially, you are in an open system (the lake) and are relying on the friction (viscosity) of the water to hold the canoe as you come back to a full sitting position.

That said, I am gradually starting to wonder whether EM drives are operating in a similar fashion.  The issue is whether EM drives really are closed or are in fact doing something like your experiment.  The question here is what is the friction that the EM drives are using.  It could be magnetism or something related to the quantum vacuum (aka the propeller theory).  It could even be something like columbic potential..

My money, rightly or wrongly, is on something simple that is surprising.
Two words: Dean drive.
Three words: Open or Closed?

Offline SeeShells

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 It is nice to have an explanation for quantum decoherence that resolves the correlation paradoxes of quantum theory, such as the Einstein Podolsky Rosen paradox and Schrödinger's cat. It is nice to know that decoherence can be resolved by general relativity, particular for people like me that don't like Everett's many world interpretation.

Having said that, as to how this relates to the EM Drive conservation of momentum problem, I don't yet see it.  The EM Drive could be a Maser, but none of the researchers have built it like a Maser. So to me the EM Drive as a macroscopic body, never achieves coherence.  Maybe I have to think some more about it :-)

Ahh.... What you seek is a theory of Quantum Gravity. None exists. I'm offering my engineering version of it as a way of bridging the classical and quantum behavior of electron "matter" waves. The "easiest" bridge I have found is through the Action of the wave functions. The EM field modifies the phase of the wave. The gravitational field is input through the metric tensor, when taking the product of the 4-vectors, <pu guv xv>. In a weak field approximation, it's simply adding a little bit more or less to the phase shift! There is no distinguishable way to know if the phase shift occurs due to gravity, or the EM potentials. Gauge transformations are also gravitational potential transformations. They have no effect on the local values of E or B because they differ only by a phase shift and a different coordinate speed of light of c/K.

Also, as Shell said, copper will not shield a magnetic field. I can emphasize that, by this she means a DC magnetic field. The AC field can't penetrate much beyond the skin depth. Correct? However, a DC magnetic field can pass right through it.

How about this proposal, conjecture.... that the evanescent waves are inducing persistent DC currents, precisely because their time average is not zero. The Volt-Seconds (magnetic flux) do not cancel! This allows mass to be stored as a DC offset in the current and the magnetic field. That DC offset can escape through the copper.

In fact, I know from experience when attempting to design DC to AC Inverters, it is very difficult to PREVENT DC offset from accumulating in a low impedance transformer. One must design special circuitry to control the reference and keep the oscillation in the flux density centered in the B/H curve of the transformer core. I was struggling to understand how the mass was increasing so significantly, now I understand that the stored current may be DC and the associated magnetic field, stored in the small end of the frustum and caused by the time-asymmetry of the evanescent wave's near-field induction effects. Along the walls of the frustum, the gauge potential has a divergence, offset by a change in the refractive index. This divergent field can escape and away we go!

Damn! I hope I said that right. Happy birthday to me!
Todd

I like this alot! You have said it much better than I could and it's what I've been thinking but still not up to the maths level you are. Nice work.

Honestly this is mostly why I'm doing the small endplate for 2.45ghz at 6.1cm using bars and spacing to allow evanescent waves to dissipate though it. I'm also doing a solid if I'm wrong.

This is why I got to thinking about this.
When the Frustum T-mode harmonics collapse creating in the small end decaying evanescent waves. It's interesting a evanescent wave is a standing wave, and could be considered a static stress-energy pressure gradient. Evanescent waves are found in near-field regions out to 1/3 wavelength of any RF antenna. http://en.wikipedia.org/wiki/Evanescent_wave

Offline deltaMass

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Two words: Dean drive.
So you are arguing the EM Drive is a weird artifact then?  Or that there may actually be the proverbial 'grain of salt' to Dean's theory?
"Dean drive" is what happened in that canoe. It's a stick/slip method of propulsion.  I'm not addressing the EmDrive, because I don't see how that could apply to it.

Offline OttO

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Universe does not like CoM violation!

I find some papers about creation of "negative mass" in tapered cavity but the universe managed to cancel any move by equalizing momentum in one way or other.

On another point, I find an interesting book:
Modelling of Mechanical Systems: Fluid-Structure Interaction : Fluid-Structure Interaction

You can find an extract attached with conical things, Schrodinger, momentum and evanescent waves  ;)

Offline flux_capacitor

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Some people (like Shawyer, TheTraveller) state we should build cavities with a length just ABOVE cut-off frequency.

Some others (like Rodal, WarpTech) state the opposite: that we should build cavities with a small end put shorter longer, just BELOW cut-off (shorter length = higher frequency).

We have also seen, in the literature from Shawyer, after experiments reported by Paul March, and by TheTraveller's spreadsheet, that at those dimensions the cavities easily detune quickly. The cavity detunes while its length is modified by less than one millimeter. So we need to precisely build solid cavities otherwise we will find ourselves below or above the cutoff frequency, although we could think we are not according to our calculation and how we designed the cavity initially.

And most importantly, let's keep in our open minds that every researcher pursuing an experimental DIY EmDrive should build several cavities, or design a special small end plate adjustable by a stepper motor, to test those statements and see which one (just below or above cutoff) works. Falsifiability is important since we don't theoretically know how the EmDrive operates.

TheTraveller finds the cut-off frequency of a frustum cavity after Shawyer, through a calculation using a series of very thin cylindrical cavities of decreasing diameters. Rodal finds the cut-off frequency of a frustum cavity through an exact solution (finite elements analysis using spherical Bessel functions). With those two independent methods, they do not find the same cut-off frequency for the same cavity length, thus for some frequency they do find a different optimal cavity length… That means we have to test FOUR cavity lengths for each cavity and each testing frequency (TheTraveller's below and above cut-off, and Rodal's below and above cut-off).

That's why it is very important for you guys to publish your theoretical numbers, to confront them with real-world experiments.
« Last Edit: 06/17/2015 09:30 AM by flux_capacitor »

Offline TheTraveller

Some people (like Shawyer, TheTraveller) state we should build cavities with a length just ABOVE cut-off frequency.

Some others (like Rodal, WarpTech) state the opposite: that we should build cavities with a small end put shorter longer, just BELOW cut-off (shorter length = higher frequency).

We have also seen, in the literature from Shawyer, after experiments reported by Paul March, and by TheTraveller's spreadsheet, that at those dimensions the cavities easily detune quickly. The cavity detunes while its length is modified by less than one millimeter. So we need to precisely build solid cavities otherwise we will find ourselves below or above the cutoff frequency, although we could think we are not according to our calculation and how we designed the cavity initially.

And most importantly, let's keep in our open minds that every researcher pursuing an experimental DIY EmDrive should build several cavities, or design a special small end plate adjustable by a stepper motor, to test those statements and see which one (just below or above cutoff) works. Falsifiability is important since we don't theoretically know how the EmDrive operates.

Length is not involved in cutoff.

It is small end plate diameter, frequency and excitation mode that determines cutoff frequency.

I would point out that the only person, who has built at least 3 successful EM Drives, Roger Shawyer, in an effort to see many more EM Drives replicated all over the planet, has shared how to do all the necessary calcs to make an operational EM Drive based on the SPR in house software.

Roger Shawyer has stated 2 No, Nos when building EM Drives.

1) Don't use a dielectric.

2) Don't operate the small end at or below cutoff.

While doing so may indeed produce some small level of thrust, to generate larger levels of thrust requires operation at cavity resonance and a high Q, which implies there is a wave to bounce off the small end plate. If the small end plate is set to operate below cutoff, then there will be little or no EM wave to bounce off the small end plate and no Q amplified thrust generation.

Todd and others seems to think the Chinese data supports lower Q = higher thrust. Well it does not. Read the attached data, which clearly shows higher Q results in higher thrust. Also note there are plenty of dimensions provided by the Chinese, which is also not what others have reported.

Bottom line if you want to try Blue Sky stuff, please do so but if you want to build a working EM Drive, then Roger Shawyer and SPR have given us all we need to do the calcs, cut metal, get resonance and thrust.

For some strange reason, even though all this SPR guidance was available to EW, they seemingly decided to go for Blue Sky stuff and got no thrust without a dielectric, using frequencies that are not, according to the SPR calc method, resonant. So no wonder they saw no thrust. Even using dielectrics, the best they got was SnowFlake thrust levels.

So you decide. Go with the SPR calc methods or go chasing SnowFlakes.

As for the calc methods, the SPR method calcs the 3.85GHz that the Flight Thruster operates at. I'm still waiting on Dr Rodal to post the freq his method generates for the Flight Thruster dimensions. You see if his method doesn't produce 3.85GHz then it is wrong as that is the frequency the Flight Thruster operates at.

Have attached the latest version of the EMDriveCalculator if anybody wants to confirm it is small end plate diameter that drives CUTOFF
« Last Edit: 06/17/2015 09:48 AM by TheTraveller »
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Offline Rodal

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So you decide. Go with the SPR calc methods or go chasing SnowFlakes.

As for the calc methods, the SPR method calcs the 3.85GHz that the Flight Thruster operates at. I'm still waiting on Dr Rodal to post the freq his method generates for the Flight Thruster dimensions. You see if his method doesn't produce 3.85GHz then it is wrong as that is the frequency the Flight Thruster operates at.

...

I already replied that I am not going to participate in a rigged game, based on second-hand information.  Roger Shawyer never published the mode shape that the Flight Thruster has at 3.85GHz.  It would be a game based on hearsay.  Moreover, it appears that Shawyer never obtained experimental verification that the mode shape was TE013 at 3.85 GHz, so it would be a rigged game based on Shawyer's beliefs rather than experimental information.  The fact that the rules of the game are based on hearsay without experimental verification make the game you insist on proposing a rigged game.

Up to this point, the only experimental information on a mode shaped has been provided by NASA Eagleworks, for mode TM212, see this experimental information provided by Paul March:



Shawyer has not provided any such experimental verification for the Flight Thruster or for any other test he has written about.

Therefore, the only way to verify a code based on EM Drive truncated cone experimental information, up to now, is this TM212 information provided by NASA, and certainly not based on hearsay from Shawyer without any experimental basis provided.

The more you push for people to accept Shawyer's prescriptions, the less credible Shawyer's claims appear. 
Pushing for people to engage in a rigged game where there is no experimental report of the mode shape to be calculated does not serve Shawyer well.
Suggestion: a better way to campaign for Shawyer's prescriptions is to independently replicate his claims, so that the EM Drive can be accepted by the technical community.
« Last Edit: 06/17/2015 12:24 PM by Rodal »

Offline rfmwguy

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So you decide. Go with the SPR calc methods or go chasing SnowFlakes.

As for the calc methods, the SPR method calcs the 3.85GHz that the Flight Thruster operates at. I'm still waiting on Dr Rodal to post the freq his method generates for the Flight Thruster dimensions. You see if his method doesn't produce 3.85GHz then it is wrong as that is the frequency the Flight Thruster operates at.

...

I already replied that I am not going to participate in a rigged game, based on second-hand information.  Roger Shawyer never published the mode shape that the Flight Thruster has at 3.85GHz.  It would be a game based on hearsay.  Moreover, it appears that Shawyer never obtained experimental verification that the mode shape was TE013 at 3.85 GHz, so it would be a rigged game based on Shawyer's beliefs rather than experimental information.

Up to this point, the only experimental information on a mode shaped has been provided by NASA Eagleworks, for mode TM212, see this experimental information provided by Paul March:



Shawyer has not provided any such experimental verification for the Flight Thruster or for any other test he has written about.

Therefore, the only way to verify a code based on EM Drive truncated cone experimental information, up to now, is this TM212 information provided by NASA, and certainly not based on hearsay from Shawyer without any experimental basis provided.

The more you push for people to accept Shawyer's prescriptions, the less that credible Shaywer appears.  Suggestion: a better way to campaign for Shaywer's prescriptions is to independently replicate his claims, so that the EM Drive can be accepted by the technical community.

Soooo...appears the descrepancy I am finding is length calc. with end plates of 6.25 and  11.01, you (ew) suggest 9.0 traveller (spr) suggest abt 10.8 in.

Care to discuss the differences doc?
This is a significant disparity.

Offline Rodal

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Soooo...appears the descrepancy I am finding is length calc. with end plates of 6.25 and  11.01, you (ew) suggest 9.0 traveller (spr) suggest abt 10.8 in.

Care to discuss the differences doc?
This is a significant disparity.
Sorry, I have not been following the discussion.

In a truncated cone everything (the mode shape, the natural frequency and the cut-off frequency) depend on all the geometrical dimensions: the diameters of both bases and the length.

Could you please re-state the problem? what is the disparity?  What are the dimensions of your cavity?
« Last Edit: 06/17/2015 12:08 PM by Rodal »

Offline rfmwguy

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Soooo...appears the descrepancy I am finding is length calc. with end plates of 6.25 and  11.01, you (ew) suggest 9.0 traveller (spr) suggest abt 10.8 in.

Care to discuss the differences doc?
This is a significant disparity.

Sorry, I have not been following the discussion.

In a truncated cone everything (the mode shape, the natural frequency and the cut-off frequency) depend on all the geometrical dimensions: the diameters of both bases and the length.

Could you please re-state the problem? what is the disparity?  What are the dimensions of your cavity?

11.01 x 6.25 endplates.

U (ew) suggest 9 in length, traveller suggests abt 10.78.

Why the diff?
Is shorter ew length due to dielectric insertion?

Offline TheTraveller

I already replied that I am not going to participate in a rigged game, based on second-hand information.  Roger Shawyer never published the mode shape that the Flight Thruster has at 3.85GHz.  It would be a game based on hearsay.  Moreover, it appears that Shawyer never obtained experimental verification that the mode shape was TE013 at 3.85 GHz, so it would be a rigged game based on Shawyer's beliefs rather than experimental information.

Up to this point, the only experimental information on a mode shaped has been provided by NASA Eagleworks, for mode TM212, see this experimental information provided by Paul March:

Shawyer has not provided any such experimental verification for the Flight Thruster or for any other test he has written about.

Therefore, the only way to verify a code based on EM Drive truncated cone experimental information, up to now, is this TM212 information provided by NASA, and certainly not based on hearsay from Shawyer without any experimental basis provided.

The more you push for people to accept Shawyer's prescriptions, the less credible Shaywer claims appear.  Suggestion: a better way to campaign for Shaywer's prescriptions is to independently replicate his claims, so that the EM Drive can be accepted by the technical community.

Long winded way to say your method can't predict the Flight Thruster resonant frequency nor mode from known dimensions and known excitation frequency.

Despite your hand waving, you don't need to know the mode. Try 80 modes as I do and find the one that gives resonance at the desired 3.85GHz and the Flight Thruster dimensions. It just happens to be TE013 as Shawyer shared with me.

You claim what Roger Shawyer has shared and I have shared with this forum is hearsay. Well it is NOT. It is what the man has said and I have provided copies of his emails. If you feel I have embellished or distorted his emails to me and Mulletron in some way, please feel free to contact Roger and verify their originality.

End result is you can't currently predict the Flight Thruster mode as TE013 nor can you currently predict the resonant frequency as 3.85GHz. As such just maybe you need to revisit your theory on how to do these calcs and realise the data you have been providing just may not be correct and may be why EW found nothing more that SnowFlake level thrust, if that.

BTW his name is Roger Shawyer and not Shaywer as you sometime use.

How is the game rigged and who did the rigging? I send the following Flight Thruster dimensions to Roger Shawyer:

Frustum big diameter        m   0.2314000
Frustum small diameter   m   0.1257000
Frustum centre length   m   0.1386000

and asked him for the resonate frequency. He sent me the following:

External Rf                   Hz   3,900,300,000

What is rigged here? Why do you refuse to do the same? As I have now asked 4 times, I suspect your solution can't predict the same resonant frequency and so you do hand waving exercises to divert attention away.
« Last Edit: 06/17/2015 12:28 PM by TheTraveller »
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Offline rfmwguy

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Soooo...appears the descrepancy I am finding is length calc. with end plates of 6.25 and  11.01, you (ew) suggest 9.0 traveller (spr) suggest abt 10.8 in.

Care to discuss the differences doc?
This is a significant disparity.

Sorry, I have not been following the discussion.

In a truncated cone everything (the mode shape, the natural frequency and the cut-off frequency) depend on all the geometrical dimensions: the diameters of both bases and the length.

Could you please re-state the problem? what is the disparity?  What are the dimensions of your cavity?

11.01 x 6.25 endplates.

U (ew) suggest 9 in length, traveller suggests abt 10.78.

Why the diff?
Is shorter ew length due to dielectric insertion?

11.01 x 6.25 endplates.

Does that mean endplates having rectangular dimensions of 11.01 x 6.25  ?

Do you have a rectangular cavity with rectangular end plates having internal dimensions of
End Plate internal length= 11.01 inches
End Plate internal width = 6.25 inches
and you want to know the natural frequencies and mode shapes for internal longitudinal distances of 9 inches and 10.78 inches ?

This is the exact solution for a rectangular boxed resonator:



See:  https://en.wikipedia.org/wiki/Microwave_cavity#Rectangular_cavity

Do you have a dielectric insert inside the cavity?

Do you have an excitation frequency for your experiment?

Circular cavity.

Internal longitudinal axis.

No dielectric.

2.45 GHz exicitation.

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