EM Drive Developments - related to space flight applications - Thread 2

[Rodal]

Hi,

Here's another first post from someone who's been reading this thread for a long time.
...

Welcome to the forum 

[hhexo]

As promised I am posting the latest draft about general relativity and electromagnetic field. The relevant conclusion is that there is thrust. Thanks to the comments by Jose Rodal, it can be shown that this can be meaningful and the best geometry is that of the frustum tending to a cone. There is no violation of conservation law due to the presence of the gravity that can escape the device producing a reaction.

I post it here for your comments that are very welcome as usual. You can find the final equation at page 12 for your evaluations. Later on, I will post a version with a somewhat different presentation to arxiv.

Thank you for an interesting paper. What I think would be helpful for anchoring the reader in reality would be a small worked example for the thrust prediction.

Thanks. Yes, you are right. It is the next step to fill with numbers and put some plots to see the orders of magnitude. I am not sure yet that I am able to account for a macroscopic effect.

*reads the paper*
... Wow. Ok, now the maths is definitely too much for a humble electronic engineer.

But I have to say, this work is impressive! I hope it can be peer-reviewed quickly and effectively, and then experimented with.

Even if the thrust was not macroscopic, I think this analysis would provide a link between EM and spacetime/gravity that could be interesting for science regardless. Maybe it would have other applications, or maybe it'll be another piece of the puzzle in our knowledge of the universe. The best result of course would be if this predicted the thrust measured for the EmDrive, but let's be calm, relaxed and skeptical about this for now.

Incidentally, since we had a "Yay for Romania!" moment in this thread for Iulian's work, may I (as an Italian expat) have a "Yay for Italy!" moment for Marco's work?

[The Amazing Catstronaut]

I've posted the files (both original Solidworks .SLDPRT and printable .STLs) on Thingiverse for anyone that wants a copy (link: http://www.thingiverse.com/thing:838001). If I get time over the next few days/weeks I'm going to try and make it easier to build, break it down into more parts, tabulate the dimensions to make it easier to modify, and maybe add some proper drawings.

Welcome to the forum! It's great here!

Not to put words under your fingers, but it sounds like you're making something of your own template for EM drive home builds. As another none-expert interested in having a shot at it, I tip my proverbial hat to you.

[CW]

By the way.. where is Iulian? I hope he has not crippled or killed himself with the magnetron.. !

[Rodal]

...

...
Incidentally, since we had a "Yay for Romania!" moment in this thread for Iulian's work, may I (as an Italian expat) have a "Yay for Italy!" moment for Marco's work?

VIVA ITALIA

forza azzurri   



Fortuna i forti aiuta, e i timidi rifiuta.

[Star One]

By the way.. where is Iulian? I hope he has not crippled or killed himself with the magnetron.. !

Similar concerns about him have been raised elsewhere. Hope he's OK.

[Giovanni DS]

By the way.. where is Iulian? I hope he has not crippled or killed himself with the magnetron.. !

Similar concerns about him have been raised elsewhere. Hope he's OK.

Date Registered:
    05/07/2015 04:30 AM
Local Time:
    05/20/2015 03:21 PM
Last Active:
    Today at 05:05 PM

Apparently he is fine.

[Rodal]

By the way.. where is Iulian? I hope he has not crippled or killed himself with the magnetron.. !

Similar concerns about him have been raised elsewhere. Hope he's OK.

Besides the obvious dangers associated with microwaves, there is the non-obvious danger of Beryllium inhalation if it gets chipped and it becomes airborne.



http://en.wikipedia.org/wiki/Beryllium_poisoning

[TheTraveller]

Moving onto frustum resonance and how to use Df to calculate end plate spacing.

We know each end has a unique guide wavelength.

If we assume the frustum is composed of 2 cylindrical sections, closed at one end and joined at the other each, with each of a length = it's guide wavelength, which says it is only what happens to guide wavelength at each end that matters to frustum resonance.

1st using lambda g1^2 (big end) / lambda g2 (small end) we get the wavelength of the external Rf that is required to generate the guide wavelengths at each end as per the Df equation. Then adjust either or both diameters to get the calculated effective guide wavelength to match the actual external wavelength.

Next knowing the guide wavelength of both ends, add them together as the target external Rf wavelength. Then adjust end plate spacing to achieve same physical spacing as the sum of the 2 end plate guide wavelengths.

Does this make sense? Seems to generate Flight Thruster dimensions close to what we have worked out.

[deltaMass]

I thought we had (x for lambda)
x0² = x1 x2
but here you say
x1² = x0 x2
which of course is not the same

where x0 is the input RF wavelength

[D_Dom]

Q: Will these equations hold for the 600 to 1500 nM wavelengths of the tapered fiber amplifiers?

[SeeShells]

As promised I am posting the latest draft about general relativity and electromagnetic field. The relevant conclusion is that there is thrust. Thanks to the comments by Jose Rodal, it can be shown that this can be meaningful and the best geometry is that of the frustum tending to a cone. There is no violation of conservation law due to the presence of the gravity that can escape the device producing a reaction.

I post it here for your comments that are very welcome as usual. You can find the final equation at page 12 for your evaluations. Later on, I will post a version with a somewhat different presentation to arxiv.

*Cherry picks the points and takes in the formulas . . . very slowly.
This is worth a hot tub print out and read. Kudos to you. My math is quite rusty but I still have enough stocked away to grasp what your inferring and so far it makes some good sense.

Reading it I had a question (more than one but..). And this is for everyone, why did Eagle Works observe no thrust in a EM device with no HDPE insert? Makes me wonder what effect achiral materials like this that can induce chirality would have with relativity and electromagnetic fields in your equations?

Thanks nice work!

[ForgeMonkey]

I've posted the files (both original Solidworks .SLDPRT and printable .STLs) on Thingiverse for anyone that wants a copy (link: http://www.thingiverse.com/thing:838001). If I get time over the next few days/weeks I'm going to try and make it easier to build, break it down into more parts, tabulate the dimensions to make it easier to modify, and maybe add some proper drawings.

Welcome to the forum! It's great here!

Not to put words under your fingers, but it sounds like you're making something of your own template for EM drive home builds. As another none-expert interested in having a shot at it, I tip my proverbial hat to you.

Thanks for the proverbial hat-tip 

I’m interested in helping in whatever way I can. I’ve spent a lot of time over the last few years designing things in CAD (mostly, but not exclusively, Solidworks), so I thought the logical place to start would be a model of the device.

I doubt I’ll be able to pursue my own independent build, as a student I doubt I’ll have the time. But, I’m more than happy to draw up, or design, custom parts for home builders in what spare time I do have. I also operate a 3D printer, (an Ultimaker v1, nothing special) so if people want printed parts for their builds just drop me a line.

I wonder if it would be worth starting a list of “consulting” engineers and specialists alongside the list of builders at ( http://emdrive.echothis.com/Building )?

[TheTraveller]

I thought we had (x for lambda)
x0² = x1 x2
but here you say
x1² = x0 x2
which of course is not the same

where x0 is the input RF wavelength

The equation supplied seems to give the effective electrical length of the frustum for resonance at the external Rf.

BUT the physical end plate spacing may not be that needed to get resonance with the INTERNAL combined guide wavelengths.

Note here Shawyer says resonance at the electrical length.

[saucyjack]

That table (http://forum.nasaspaceflight.com/index.php?topic=36313.msg1302455#msg1302455 ) was dated 12/14/2014, more than 5 months ago.

The table was the result of the best efforts of a team of people that have been in this thread from the beginning, working with this "EM Drive tar baby" where researchers report experimental measurements without giving the dimensions of the cavities used in the experiments .

This data is some of the most-referenced in the entire thread.  To make it easier to read, I reformatted it into this page on the wiki.  As the estimated dimensions and other parameters are revised, and tests run on new device variations, they can easily be updated there. 

In addition if there is other content that should be replicated there (I'm thinking of theory equations and derivations in particular), let me know - or just jump in yourself.  The wiki now supports MathJax so the math there can be more readable than what we can do in a forum post.

Any other comments on how to make the wiki more useful, please PM me.  It's been averaging a few updates a day by various folks, so is starting to grow.

-Rolf

[Rodal]

That table (http://forum.nasaspaceflight.com/index.php?topic=36313.msg1302455#msg1302455 ) was dated 12/14/2014, more than 5 months ago.

The table was the result of the best efforts of a team of people that have been in this thread from the beginning, working with this "EM Drive tar baby" where researchers report experimental measurements without giving the dimensions of the cavities used in the experiments .

This data is some of the most-referenced in the entire thread.  To make it easier to read, I reformatted it into this page on the wiki.  As the estimated dimensions and other parameters are revised, and tests run on new device variations, they can easily be updated there. 

In addition if there is other content that should be replicated there (I'm thinking of theory equations and derivations in particular), let me know - or just jump in yourself.  The wiki now supports MathJax so the math there can be more readable than what we can do in a forum post.

Any other comments on how to make the wiki more useful, please PM me.  It's been averaging a few updates a day by various folks, so is starting to grow.

-Rolf

Thanks for doing all this work.  Very noble of you.

Please notice these minor corrections:

Fearn, Zachar, Woodward & Wanser:  not a microwave cavity, but is instead a piezoelectric MET thruster (Woodward Mach Effect)

Hence it doesn't have cavity dimensions:  0.2286   0.2794   0.15875

It is included because Prof. Woodward's device is also a propellant-less concept, and because Paul March (NASA) maintains that Prof. Woodward's Mach Effect theory might also be, in his opinion, an explanation for thrust for the EM Drive.


Cannae Superconducting should read:

measured ForcePerPowerInput = 761.9 to 952.4

[rfmwguy]

By the way.. where is Iulian? I hope he has not crippled or killed himself with the magnetron.. !

Similar concerns about him have been raised elsewhere. Hope he's OK.

Besides the obvious dangers associated with microwaves, there is the non-obvious danger of Beryllium inhalation if it gets chipped and it becomes airborne.



http://en.wikipedia.org/wiki/Beryllium_poisoning

Well said. BeO is a common ceramic used in electronics. The grinding, sanding or drilling will make particulates airborne and if inhaled into lungs is dangerous. Normal handling or touching is OK...just do NOT try and modify the surface at all. This from my previous life working with microwave attenuators' substrates. GREAT thermal characteristics, however...

[Rodal]

...
Reading it I had a question (more than one but..). And this is for everyone, why did Eagle Works observe no thrust in a EM device with no HDPE insert? Makes me wonder what effect achiral materials like this that can induce chirality would have with relativity and electromagnetic fields in your equations?

Thanks nice work!

Excellent question that has been puzzling me for a long time as well.  To examine this, first let's recapitulate the statement in Brady et.al.' report:

There appears to be a clear dependency between thrust magnitude and the presence of some sort of dielectric RF resonator in the thrust chamber. The geometry, location, and material properties of this resonator must be evaluated using numerous COMSOL® iterations to arrive at a viable thruster solution. We performed some very early evaluations without the dielectric resonator (TE012 mode at 2168 MHz, with power levels up to ~30 watts) and measured no significant net thrust

My exact solution for the truncated cone, given the dimensions reported by Paul March and also used in NASA's COMSOL FEA analysis, for mode shape TE012, gives me a natural frequency of:

2.2024 GHz

So they operated at frequency of 2.168 GHz which is 1.59% away from the frequency given by the exact solution. Perhaps the reason was that that was the frequency given by the Finite Element analysis for mode TE012 (let's recall that the Finite Element solution converges from below to the correct eigensolution, and only for an infinite Finite Element mesh one can theoretically converge to the eigensolution).  So, they were looking in the right frequency range for TE012.

My recollection is that Paul March thought that the reason maybe that to generate thrust without a dielectric one needs to provide Amplitude, Frequency and Phase Modulation, and that at the time of the experiments detailed in the NASA report ( http://www.libertariannews.org/wp-content/uploads/2014/07/AnomalousThrustProductionFromanRFTestDevice-BradyEtAl.pdf ), they were not providing the needed AM, FM and PM modulation.  I was not able to find the exact quotation (I wonder why, given the fantastic search function we have at this site  ).  I was only able to find this quotation from Paul March, in answer to this question:

(Shawyer and the Chinese used the magnetron excited TE012 mode in their frustum cavities without dielectrics being present.)

[Rodal]

That table (http://forum.nasaspaceflight.com/index.php?topic=36313.msg1302455#msg1302455 ) was dated 12/14/2014, more than 5 months ago.

The table was the result of the best efforts of a team of people that have been in this thread from the beginning, working with this "EM Drive tar baby" where researchers report experimental measurements without giving the dimensions of the cavities used in the experiments .

This data is some of the most-referenced in the entire thread.  To make it easier to read, I reformatted it into this page on the wiki.  As the estimated dimensions and other parameters are revised, and tests run on new device variations, they can easily be updated there. 

In addition if there is other content that should be replicated there (I'm thinking of theory equations and derivations in particular), let me know - or just jump in yourself.  The wiki now supports MathJax so the math there can be more readable than what we can do in a forum post.

Any other comments on how to make the wiki more useful, please PM me.  It's been averaging a few updates a day by various folks, so is starting to grow.

-Rolf

Also, if you could be so kind to do this for us, when you have a chance:

1) reads:          Brady c TM Mode
    should read:  Brady c TE Mode


2) If you have the space for another column, (perhaps by narrowing the column for the DesignFactor), could you please insert another column titled "Dielectric" that should read

For all the Brady cases:    HDPE

For all the other cases:    No dielectric

3) Instead of the simple title "Dimensions" for your comprehensive table, how about using instead:

"Experimental Data: Forces, Power, Frequency and Dimensions"

[StrongGR]

As promised I am posting the latest draft about general relativity and electromagnetic field. The relevant conclusion is that there is thrust. Thanks to the comments by Jose Rodal, it can be shown that this can be meaningful and the best geometry is that of the frustum tending to a cone. There is no violation of conservation law due to the presence of the gravity that can escape the device producing a reaction.

I post it here for your comments that are very welcome as usual. You can find the final equation at page 12 for your evaluations. Later on, I will post a version with a somewhat different presentation to arxiv.

*Cherry picks the points and takes in the formulas . . . very slowly.
This is worth a hot tub print out and read. Kudos to you. My math is quite rusty but I still have enough stocked away to grasp what your inferring and so far it makes some good sense.

Reading it I had a question (more than one but..). And this is for everyone, why did Eagle Works observe no thrust in a EM device with no HDPE insert? Makes me wonder what effect achiral materials like this that can induce chirality would have with relativity and electromagnetic fields in your equations?

Thanks nice work!

Thanks a lot. The reason why a material can change the behaviour is magnetic permeability. This can enhance the effect by several magnitude orders. They use low input power, if I am right, and so this could be a good way around to such a limitation.