### Author Topic: EM Drive Developments - related to space flight applications - Thread 3  (Read 1876303 times)

#### Rodal

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##### Re: EM Drive Developments - related to space flight applications - Thread 3
« Reply #3400 on: 07/06/2015 01:44 AM »
http://gregegan.customer.netspace.net.au/SCIENCE/Cavity/Cavity.html
The equations for the em fields of a tampered conical waveguide can be founded above.
The expressions for the cavity( for more simple modes) are founded after matching boundaring conditons at the taps.
The geometry is matched by spherical coordinates, so the fields are spherical coordinate dependent too, an this facilitate match the boundary conditions by aproximation ( the taps are not spherical but planes in real cavity).
But the point is, the fields are expressed by coordinates functions, but the the wave vectors not. In fact the wave vectors are "the coordinates"  the modes of propagation, where the modes are a base to span the function space of em fields inside the guide/cavity.

Your first equation ( the definition of the wave vector K), is wrong.
It establishes a erroneous z dependence on K.
The K will depend at most on total geometry( including the dimensions of cavity), medium constitutive relations (mu and epslon), and boundary conditions, which defines de modes inside the sctruture, and thus the modes cut off frequencys.

I am not describing a cavity. It's an open ended tapered waveguide and the radius "IS" dependent on the z coordinate. Can you provide a better way to derive the propagation vector kz for a tapered waveguide than to parameterize the radius in terms of z? The radius is a variable in this waveguide, as is the transverse resonant frequency. Both are dependent on the location along the z axis of the waveguide. It is not "erroneous", it is precisely what makes the tapered waveguide different from a straight one.

EDIT: You said in a previous post,

Quote from: Ricvil
"...The conical geometry of cavity can produce a gradient intensity of the fields inside it, and resulting on a axial non symmetric scattering of axions (produced by the stationary wave of hybrid modes), and thus the thrust is formed....".

Are you saying that you believe the conical geometry can produce a gradient thrust only with axions but not with transverse, resonant EM standing waves? The equation I derived is exactly that, the gradient in the potential energy stored in the transverse standing wave as it travels down the waveguide. How else would you do it than to parameterize the potential energy wrt z?
Todd

1) Those equations from Greg Egan only model standing waves frozen in place in the cavity.  This is not what Todd is modeling.

2) Those equations from Greg Egan assume ab initio a sinusoidal fluctuation with time of the electromagnetic field.

3) Egan only gives the solutions for the m=0 mode that is constant in the azimuthal direction.  It is inapplicable to higher order modes, for example TM212 used by NASA Eagleworks or the TM114 mode in the RFMWGUY recently modeled with Aero.

4) Egan also ignores the DC solution.

5) Egan does not take into account the RF feed at all.  All EM Drive experiments have been conducted with the RF feed ON.  With the RF feed off there is no measured force.

6) Egans' conclusion regarding the Poynting vector is only applicable for the restricted case he considers: standing waves and no RF feed on in the cavity.

7) The geometry analyzed by Egan does not lead to a closed-form solution: Egan has to solve two eigenvalue problems numerically: one in terms of Associated Legendre Functions and another eigenvalue problem in terms of Spherical Bessel Functions.  Egan was not the first to solve the spherical truncated cone this way.  It was first done by Schelkunoff prior to the end of WWII.

8) In order to avoid the drastic assumptions made by Egan (that lead to no thrust whatsoever, since Egan only considers standing waves), Todd simplifies the geometry to a more amenable one that is subject to a mathematical closed-form solution (otherwise the eigenvalue problem would need to be solved numerically).

9) Instead of modeling a truncated cone as done by Egan, Todd is modeling a truncated square pyramid
in order to arrive at an amenable closed-form solution.

10) I have not had the time to check Todd's solution, but it looks like he is taking a similar approach as Dr.Nososureofit, who in previous threads described the alternate formalism of considering the x dependence of the wavenumber k, see:

http://emdrive.wiki/@notsosureofit_Hypothesis

for more details.  Dr. N. describes this as follows:

<<Rotate the dispersion relation of the cavity into doppler frame to get the Doppler shifts, that is to say, look at the dispersion curve intersections of constant wave number instead of constant frequency>>
« Last Edit: 07/06/2015 02:14 AM by Rodal »

#### SeeShells

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##### Re: EM Drive Developments - related to space flight applications - Thread 3
« Reply #3401 on: 07/06/2015 01:52 AM »
meep images.

If you want 3d rendered version of these, let me know which...I am using a graphic ray-tracing program (www.povray.org) and have it coded and parameterized, so I can generate the 3d stuff pretty quickly...
That would be over the top... Thanks!

#### aero

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##### Re: EM Drive Developments - related to space flight applications - Thread 3
« Reply #3402 on: 07/06/2015 02:03 AM »
Dr. Rodal,
The yz slices along the cavity axis are up. Same top level csv file. Read and understand the description, I won't try to explain my naming convention until/unless more or different information is needed. Ask.
I did not see a text file with a description.
The files are labeled as follows in this example:

exx-s03-m26

e= Electric Field (h for magnetizing field)
xx= x component in the plane with normal x (where x is the Cartesian axis oriented along the longitudinal axis  of axisymmetry of the cone)
s03=time step 03
m = does this mean "metal model" ?  (and if so, "p" stands for copper model ?)
26 = this must be an identifier of the x position, if so I don't understand why the number 26 instead of 150 though

Over on the right margin there is a text entry labelled  "Description" in my views of Google drive. Is that not shared?

The dash - looks like a minus sign, and I use dashes in the file name. So instead of a dash to negate, I used m, and instead of a + I used p. p and m stand-in for + and -.

They are labelled 85, 26, -26 and -85 because I'm using the slice number which is based on zero at the center of the cavity. The csv line numbers aren't meaningful to h5tocsv. Maybe I could do it differently so that they were, but I didn't. So to get the csv file line number, move the origin from the center 0 to one end or the other and calculate the line number. But that is why I did both positive and negative data slices, so I'd have the right data slice no matter which way you moved to your line numbers. Either add 123 or subtract 123 to get csv file line numbers. I find it very confusing.

Added - So you need to see at least one time slice including ey, ez and hy, hz. Well, I'll do that but after you let me know that you understand my file naming code. Do neither of us any good to have data that you can't associate with a place in the cavity.
« Last Edit: 07/06/2015 02:19 AM by aero »
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#### Rodal

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##### Re: EM Drive Developments - related to space flight applications - Thread 3
« Reply #3403 on: 07/06/2015 02:11 AM »
...
Over on the right margin there is a text entry labelled  "Description" in my views of Google drive. Is that not shared?
No such text entry appears on my Google Drive in my computer.  Only the files appear.

Anyway please take a gander at my later message.  The Poynting vector cannot be calculated unless one has all 6 components of the electromagnetic field.  exx and hxx are not enough.

#### TheTraveller

##### Re: EM Drive Developments - related to space flight applications - Thread 3
« Reply #3404 on: 07/06/2015 02:36 AM »
Following discussions with Roger Shawyer, I now understand why using a scale to measure EMDrive Force generation is a waste of time.

Hey Traveller,

When I asked about this back in May, you replied that Shawyer has "placed them directly on scales, hung them from springs above scales, used balance beams with scales, plus he used a rotary air bearing system to show true acceleration."  Are you now saying that Shawyer does not believe that his scales based experiments returned useful results, or are you saying that they were more complicated then they appeared, and were not simply a shielded drive sitting on a scale?

~Kirk

All measurement system progress.

For SPR and their EMDrive considerable progress has been made in understanding the dynamics of the device and how to best place an EMDrive into an enviroment which will allow max Force generation to develope and be measured.

Scales have been used and can still be used but with varying results because as soon as the initial Force generation to movement via compression of the measurement system occurs, movement stops and the EMDrive flips into 1st IDLE mode and then GENERATOR mode as the EMDrive resists the effort of the scale to push back the initial compressive effort.

So sure while you can get an indication of EMDrive generated Force on a scale, it is better to use a rotary test rig as then the EMDrive can continuesly accelerate.
« Last Edit: 07/06/2015 02:46 AM by TheTraveller »
"As for me, I am tormented with an everlasting itch for things remote. I love to sail forbidden seas.”
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#### Rodal

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##### Re: EM Drive Developments - related to space flight applications - Thread 3
« Reply #3405 on: 07/06/2015 02:59 AM »
Dr. Rodal,
The yz slices along the cavity axis are up. Same top level csv file. Read and understand the description, I won't try to explain my naming convention until/unless more or different information is needed. Ask.
I did not see a text file with a description.
The files are labeled as follows in this example:

exx-s03-m26

e= Electric Field (h for magnetizing field)
xx= x component in the plane with normal x (where x is the Cartesian axis oriented along the longitudinal axis  of axisymmetry of the cone)
s03=time step 03
m = does this mean "metal model" ?  (and if so, "p" stands for copper model ?)
26 = this must be an identifier of the x position, if so I don't understand why the number 26 instead of 150 though

Over on the right margin there is a text entry labelled  "Description" in my views of Google drive. Is that not shared?

The dash - looks like a minus sign, and I use dashes in the file name. So instead of a dash to negate, I used m, and instead of a + I used p. p and m stand-in for + and -.

They are labelled 85, 26, -26 and -85 because I'm using the slice number which is based on zero at the center of the cavity. The csv line numbers aren't meaningful to h5tocsv. Maybe I could do it differently so that they were, but I didn't. So to get the csv file line number, move the origin from the center 0 to one end or the other and calculate the line number. But that is why I did both positive and negative data slices, so I'd have the right data slice no matter which way you moved to your line numbers. Either add 123 or subtract 123 to get csv file line numbers. I find it very confusing.

Added - So you need to see at least one time slice including ey, ez and hy, hz. Well, I'll do that but after you let me know that you understand my file naming code. Do neither of us any good to have data that you can't associate with a place in the cavity.

I understand that the notation is the same as I understood previously with the exceptions that:

1) You have 4 cross sections instead of just two: -85, -26, +26 and +85.

2) There is only one material model.  I don't recall you stating whether copper or perfect metal, but it does not make any difference anyway.

#### kml

##### Re: EM Drive Developments - related to space flight applications - Thread 3
« Reply #3406 on: 07/06/2015 03:02 AM »

http://www.microwaves101.com/encyclopedias/waveguide-mathematics#velocity

Inside a waveguide, the wave travels at group velocity and not at phase velocity which would be faster than c.

Shawyer is correct to model end plate forces based on end plate group velocity, which is related to guide wavelength as per the attached.

Any text on waveguides will tell you the energy in the waveguide propogates down the waveguide at group velocity speed.

Interesting fact that I have pointed out before:   guide wavelength increases as cutoff dimensions approach operating frequency, however guide wavelength decreases when entering a dielectric (or higher permeability material).    The effect of practical dielectrics are so strong that they override the effect of tapering for most designs.  This could possibly cause a reversal of force direction depending on if the force depends on group velocity or guide wavelength.

Build update:

I am working on making my test unit more RF tight to minimize RFI with the scale.  I also found that placing a copper sheet over the scale pan helps.   With these steps I hope to be able to detect legitimate force signatures while quantifying any RFI effects so they can be identified in the data.  The RFI effects are very consistent and reproducable so it should not be a problem to subtract them from the data.   Of significant note is that the RFI effects have always been observed to reduce indicated weight, never increase it.  Any convincing force signal will have to show an increase in weight in one direction with no increase in same orientation while suspended above the scale.
« Last Edit: 07/06/2015 03:08 AM by kml »

#### Ricvil

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##### Re: EM Drive Developments - related to space flight applications - Thread 3
« Reply #3407 on: 07/06/2015 03:03 AM »
http://gregegan.customer.netspace.net.au/SCIENCE/Cavity/Cavity.html
The equations for the em fields of a tampered conical waveguide can be founded above.
The expressions for the cavity( for more simple modes) are founded after matching boundaring conditons at the taps.
The geometry is matched by spherical coordinates, so the fields are spherical coordinate dependent too, an this facilitate match the boundary conditions by aproximation ( the taps are not spherical but planes in real cavity).
But the point is, the fields are expressed by coordinates functions, but the the wave vectors not. In fact the wave vectors are "the coordinates"  the modes of propagation, where the modes are a base to span the function space of em fields inside the guide/cavity.

1- So Todd is not modeling a cavity, just a waveguide?  Ok
Egan has modeled both ( traveling waves - Rplus and Rminus) and standing waves resulting from reflections on the taps ( boundary conditons forced at the taps)

2- Yes, they are time harmonic solutions ( Frequency Domain) , but with they are the base to construct the called green-function, wich models any excitation inside waveguide/cavity. For a transient analysis, Time domain solutions are better to see transient responses.

3-Egan has used m=0 modes to simplify the expressions, but a numerical search on boundary conditions will produce all possibles modes.

4- DC solution on a Faraday cage?

5-Any RF feed can be modeled by a superposition of em modes. The modes are like base vectors on function space. Any function inside waveguide/cavity can be modeled by a mode superposition ( like a Fourier analysis). If no individual mode produce a net force, then a summ of them will not produce anything at all.

6- No. RF feeds are just superposition of modes, and stand waves are just two counter propagating modes.

7- Yes, closed-form solutions of this geometry would come from closed expressions for the bessel functions zeros and associated legendre polinomials. Anyone has this expressions? No? Then numeric solution is the only way.

8,9,10- And you believes Todd has found closed expression of the field of a pyramidal waveguide on a very simple form? Matching the boundary conditions of the em fields at the tappered rectangular geometry? And the expressions are that with wave vectors varying with z coordinate?

Ok.

Your first equation ( the definition of the wave vector K), is wrong.
It establishes a erroneous z dependence on K.
The K will depend at most on total geometry( including the dimensions of cavity), medium constitutive relations (mu and epslon), and boundary conditions, which defines de modes inside the sctruture, and thus the modes cut off frequencys.

I am not describing a cavity. It's an open ended tapered waveguide and the radius "IS" dependent on the z coordinate. Can you provide a better way to derive the propagation vector kz for a tapered waveguide than to parameterize the radius in terms of z? The radius is a variable in this waveguide, as is the transverse resonant frequency. Both are dependent on the location along the z axis of the waveguide. It is not "erroneous", it is precisely what makes the tapered waveguide different from a straight one.

EDIT: You said in a previous post,

Quote from: Ricvil
"...The conical geometry of cavity can produce a gradient intensity of the fields inside it, and resulting on a axial non symmetric scattering of axions (produced by the stationary wave of hybrid modes), and thus the thrust is formed....".

Are you saying that you believe the conical geometry can produce a gradient thrust only with axions but not with transverse, resonant EM standing waves? The equation I derived is exactly that, the gradient in the potential energy stored in the transverse standing wave as it travels down the waveguide. How else would you do it than to parameterize the potential energy wrt z?
Todd

1) Those equations from Greg Egan only model standing waves frozen in place in the cavity.  This is not what Todd is modeling.

2) Those equations from Greg Egan assume ab initio a sinusoidal fluctuation with time of the electromagnetic field.

3) Egan only gives the solutions for the m=0 mode that is constant in the azimuthal direction.  It is inapplicable to higher order modes, for example TM212 used by NASA Eagleworks or the TM114 mode in the RFMWGUY recently modeled with Aero.

4) Egan also ignores the DC solution.

5) Egan does not take into account the RF feed at all.  All EM Drive experiments have been conducted with the RF feed ON.  With the RF feed off there is no measured force.

6) Egans' conclusion regarding the Poynting vector is only applicable for the restricted case he considers: standing waves and no RF feed on in the cavity.

7) The geometry analyzed by Egan does not lead to a closed-form solution: Egan has to solve two eigenvalue problems numerically: one in terms of Associated Legendre Functions and another eigenvalue problem in terms of Spherical Bessel Functions.  Egan was not the first to solve the spherical truncated cone this way.  It was first done by Schelkunoff prior to the end of WWII.

In order to avoid the drastic assumptions made by Egan (that lead to no thrust whatsoever, since Egan only considers standing waves), Todd simplifies the geometry to a more amenable one that is subject to a mathematical closed-form solution (otherwise the eigenvalue problem would need to be solved numerically).

9) Instead of modeling a truncated cone as done by Egan, Todd is modeling a truncated square pyramid
in order to arrive at an amenable closed-form solution.

10) I have not had the time to check Todd's solution, but it looks like he is taking a similar approach as Dr.Nososureofit, who in previous threads described the alternate formalism of considering the x dependence of the wavenumber k, see:

http://emdrive.wiki/@notsosureofit_Hypothesis

for more details.

#### TheTraveller

##### Re: EM Drive Developments - related to space flight applications - Thread 3
« Reply #3408 on: 07/06/2015 03:08 AM »

http://www.microwaves101.com/encyclopedias/waveguide-mathematics#velocity

Inside a waveguide, the wave travels at group velocity and not at phase velocity which would be faster than c.

Shawyer is correct to model end plate forces based on end plate group velocity, which is related to guide wavelength as per the attached.

Any text on waveguides will tell you the energy in the waveguide propogates down the waveguide at group velocity speed.

Interesting fact that I have pointed out before:   guide wavelength increases as cutoff dimensions approach operating frequency, however guide wavelength decreases when entering a dielectric (or higher permeability material).    The effect of practical dielectrics are so strong that they override the effect of tapering for most designs.  This could possibly cause a reversal of force direction depending on if the force depends on group velocity or guide wavelength.

Shawyers 1st UK patent used a non tapered waveguide with a tapered dielectric at one end

"As for me, I am tormented with an everlasting itch for things remote. I love to sail forbidden seas.”
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#### aero

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##### Re: EM Drive Developments - related to space flight applications - Thread 3
« Reply #3409 on: 07/06/2015 03:31 AM »
I have placed the attached text file in the csv files folder.
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#### WarpTech

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##### Re: EM Drive Developments - related to space flight applications - Thread 3
« Reply #3410 on: 07/06/2015 03:37 AM »
http://gregegan.customer.netspace.net.au/SCIENCE/Cavity/Cavity.html
The equations for the em fields of a tampered conical waveguide can be founded above.
The expressions for the cavity( for more simple modes) are founded after matching boundaring conditons at the taps.
The geometry is matched by spherical coordinates, so the fields are spherical coordinate dependent too, an this facilitate match the boundary conditions by aproximation ( the taps are not spherical but planes in real cavity).
But the point is, the fields are expressed by coordinates functions, but the the wave vectors not. In fact the wave vectors are "the coordinates"  the modes of propagation, where the modes are a base to span the function space of em fields inside the guide/cavity.

I am not describing a cavity. It's an open ended tapered waveguide and...

1) Those equations from Greg Egan only model standing waves frozen in place in the cavity.  This is not what Todd is modeling.

2) Those equations from Greg Egan assume ab initio a sinusoidal fluctuation with time of the electromagnetic field.

3) Egan only gives the solutions for the m=0 mode that is constant in the azimuthal direction.  It is inapplicable to higher order modes, for example TM212 used by NASA Eagleworks or the TM114 mode in the RFMWGUY recently modeled with Aero.

4) Egan also ignores the DC solution.

5) Egan does not take into account the RF feed at all.  All EM Drive experiments have been conducted with the RF feed ON.  With the RF feed off there is no measured force.

6) Egans' conclusion regarding the Poynting vector is only applicable for the restricted case he considers: standing waves and no RF feed on in the cavity.

7) The geometry analyzed by Egan does not lead to a closed-form solution: Egan has to solve two eigenvalue problems numerically: one in terms of Associated Legendre Functions and another eigenvalue problem in terms of Spherical Bessel Functions.  Egan was not the first to solve the spherical truncated cone this way.  It was first done by Schelkunoff prior to the end of WWII.

In order to avoid the drastic assumptions made by Egan (that lead to no thrust whatsoever, since Egan only considers standing waves), Todd simplifies the geometry to a more amenable one that is subject to a mathematical closed-form solution (otherwise the eigenvalue problem would need to be solved numerically).

9) Instead of modeling a truncated cone as done by Egan, Todd is modeling a truncated square pyramid
<snip> in order to arrive at an amenable closed-form solution.

10) I have not had the time to check Todd's solution, but it looks like he is taking a similar approach as Dr.Nososureofit, who in previous threads described the alternate formalism of considering the x dependence of the wavenumber k, see:

http://emdrive.wiki/@notsosureofit_Hypothesis

for more details.  Dr. N. describes this as follows:

<<Rotate the dispersion relation of the cavity into doppler frame to get the Doppler shifts, that is to say, look at the dispersion curve intersections of constant wave number instead of constant frequency>>

Thank you Jose. The equations I posted yesterday, http://forum.nasaspaceflight.com/index.php?topic=37642.msg1400288#msg1400288, are for a tapered circular waveguide with open ends. It is not a truncated pyramid because, the z-dependence (axial coordinate) is identical, regardless if I parameterize a circle, a square or a rectangle. The gradient due to the taper is the same, and the traveling wave in the z-direction is not a standing wave in a cavity.

You are correct, I am trying to simplify the problem to demonstrate that the thrust of a photon rocket is not simply F=P/c. My result is very close to what @Notsosureofit has in his proposal, with more detail. I have no reason or desire to solve the eigenvalue problem for a closed truncated frustum cavity. It is not necessary or pertinent to the rocket equation I've provided.
Todd

#### Rodal

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##### Re: EM Drive Developments - related to space flight applications - Thread 3
« Reply #3411 on: 07/06/2015 03:43 AM »
...

Thank you Jose. The equations I posted yesterday, http://forum.nasaspaceflight.com/index.php?topic=37642.msg1400288#msg1400288, are for a tapered circular waveguide with open ends. It is not a truncated pyramid because, the z-dependence (axial coordinate) is identical, regardless if I parameterize a circle, a square or a rectangle. The gradient due to the taper is the same, and the traveling wave in the z-direction is not a standing wave in a cavity.

You are correct, I am trying to simplify the problem to demonstrate that the thrust of a photon rocket is not simply F=P/c. My result is very close to what @Notsosureofit has in his proposal, with more detail. I have no reason or desire to solve the eigenvalue problem for a closed truncated frustum cavity. It is not necessary or pertinent to the rocket equation I've provided.
Todd
I was referring to your previous equation containing A(x) for a square cross section, in this message:

http://forum.nasaspaceflight.com/index.php?topic=37642.msg1399882#msg1399882

<<Xmn2 = [(m*pi/A*tanθ)2 + (n*pi/B*tanθ)2], for a tapered rectangular waveguide of width and height;>>

By the way, on the answer by  Ricvil (who instead favors axions as respsonsible for the force), superposition of solutions is inapplicable to nonlinear problems.
« Last Edit: 07/06/2015 03:54 AM by Rodal »

#### WarpTech

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##### Re: EM Drive Developments - related to space flight applications - Thread 3
« Reply #3412 on: 07/06/2015 03:55 AM »
...

4- DC solution on a Faraday cage?

...

DC and slowly varying magnetic fields can pass through copper, especially when it is hot and has a high resistance and voltage drop. If there are persistent circulating currents around the circumference of the frustum, the DC magnetic field can escape. That is one method by which I've hypothesized that the momentum can escape. A magnetron is pulsed negative 4kV at 60Hz. It could result in a circulating quasi-DC current.
Todd

#### Ricvil

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##### Re: EM Drive Developments - related to space flight applications - Thread 3
« Reply #3413 on: 07/06/2015 04:01 AM »
https://en.m.wikipedia.org/wiki/Microwave_cavity#Cylindrical_cavity

Now I see where the expressions comes from.

The cut off frequency expressions for constant radius R cilindrical waveguide.

It's wrong because,  the expressions for constant radius waveguides are used like dispersions relations of a tappered waveguide , and the " constant radius R" is used as a function of spacial coordinates.
Not only this, derivatives of this  expressions are done acting on the"ad-hoc" spacial dependency introduced.

Wrong!!!

#### TheTraveller

##### Re: EM Drive Developments - related to space flight applications - Thread 3
« Reply #3414 on: 07/06/2015 04:07 AM »
Interesting news.

My yongest son lectures at the local uni (he is a honours software engineering and physics grad, working on his Masters). He has discussed my planned series of experiments with a few people in the physics department. Seems there is enough interest to schedule a meeting on how we may be able to cooperate in the experimental test runs/data collection and to potentially publish the results in a peer reviewed journal.

Should be interesting.
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#### ThinkerX

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##### Re: EM Drive Developments - related to space flight applications - Thread 3
« Reply #3415 on: 07/06/2015 04:18 AM »
If I am following Warp Tech correctly, then the thrust produced by his open ended EM Drive / Photon Rocket design is roughly on a par with the Maser design Doctor Bae is experimenting with.  The one requiring two spacecraft.  I wonder if this near convergence is indicative of some sort of true upper limit for the EM Drive?  (once thermal and other artefacts are allowed for)

Also been wondering a bit about the MEEP movies.  They show a single cycle.  Yet this device should have millions (?) of cycles per second, and billions for an extended period at a minimum.  So, given increasing thermal effects, and perhaps other issues, maybe the cycle alters somehow after a few hundred million repetitions?

#### ludkokanta

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##### Re: EM Drive Developments - related to space flight applications - Thread 3
« Reply #3416 on: 07/06/2015 05:05 AM »
I am a bit affraid about this but I don't think it will be too easy to figure out. I disclosed it and discussed it with a doctor of physics specialised in quantum. He said "I still don't belive it works but I saw it".

I am interested in your thoughts about commercial application. Obviously, Shawyer has a few Patents... But there is a just a handfull of investors who could develop this into commercial tehnology.

#### deltaMass

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##### Re: EM Drive Developments - related to space flight applications - Thread 3
« Reply #3417 on: 07/06/2015 05:20 AM »
How much power for how much thrust?

#### TheTraveller

##### Re: EM Drive Developments - related to space flight applications - Thread 3
« Reply #3418 on: 07/06/2015 08:44 AM »
I am a bit affraid about this but I don't think it will be too easy to figure out. I disclosed it and discussed it with a doctor of physics specialised in quantum. He said "I still don't belive it works but I saw it".

I am interested in your thoughts about commercial application. Obviously, Shawyer has a few Patents... But there is a just a handfull of investors who could develop this into commercial tehnology.

Commercial applications?

1) can it scale?

2) can it generate more than 9.8N/1kg of total device & power supply mass?

If so it may be the end of Wheels, Wings and Rockets.

Big enough market for you?

Then consider that all the companies with 100s of billions (probably trillions) of sunk capital in Wheels, Wings and Rockets may wish to protect their investments and share prices.
« Last Edit: 07/06/2015 08:52 AM by TheTraveller »
"As for me, I am tormented with an everlasting itch for things remote. I love to sail forbidden seas.”
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#### Rodal

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##### Re: EM Drive Developments - related to space flight applications - Thread 3
« Reply #3419 on: 07/06/2015 12:42 PM »
I am a bit affraid about this but I don't think it will be too easy to figure out. I disclosed it and discussed it with a doctor of physics specialised in quantum. He said "I still don't belive it works but I saw it".

I am interested in your thoughts about commercial application. Obviously, Shawyer has a few Patents... But there is a just a handfull of investors who could develop this into commercial tehnology.