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#2160 by Jerry Hynecek on 23 Jan, 2016 08:39
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#2161 by Flyby on 23 Jan, 2016 09:54
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Just an idea (from a layman point of view)
There have been some tests with dielectrics but has anyone done any experiments with stronger diamagnetic materials (compared to copper) such as bismuth? Bismuth is fairly cheap and it is easily molded. Perhaps someone can clue me in if this would make any difference whatsoever.
Cheers
I recall the discussion about magnetic permeability and the possible use of metglas 2714A, and Todd's suggestion to use it on the large end of the frustum...
http://www.metglas.com/products/magnetic_materials/2714a.asp
as "cheaper" alternative , one could use 99.95% pure iron...
https://en.wikipedia.org/wiki/Permeability_%28electromagnetism%29 -
#2162 by Mulletron on 23 Jan, 2016 12:35
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Please comment on the theory.
http://gsjournal.net/Science-Journals/%7B$cat_name%7D/View/6323
I agree with you on the gravitational waves being worthy of consideration, but I think it's too early to say such things with confidence or authority, because they haven't even been directly observed yet. That is simply my opinion based on a personal choice to stick with mechanisms which have some basis in reality, e.g. verified by some experiment, or at least a logically applied application of that knowledge. Anyway, here's some observations from a quick skim of your paper.QuoteThe key problem, however, is that the EM waves are transversal and the gravitational waves are longitudinal.
I'm pretty sure gravitational waves are transverse quadrupolar waves, not longitudinal. We'll find out for sureonceif they're detected and analyzed. This reference explains in depth how longitudinal gravitational waves are, ahem...unlikely. http://www.tapir.caltech.edu/~teviet/Waves/gwave.html (ctrl-f for "Now consider the case of gravitation. Once again, conservation of mass prevents monopole radiation.")QuoteThis DM supports the propagation of light as transversal electromagnetic (EM) waves and the propagation of gravity as the longitudinal waves, both with the same velocity c when measured away from gravitating bodies.
I think the inclusion of dark matter as an "aether" to support the propagation of radiation is an unnecessary layer of speculation which could be left out of the theory altogether. We've known since the Michelson–Morley experiment that we don't need an aether to support the propagation of electromagnetic radiation. (I am aware that Einstein rejected the aether with SR and famously brought back the aether with GR , but that is outside the scope of this.)QuoteIt is also difficult to judge from the pictures of the apparatus how long the resonator cavity is.
We know the exact dimensions of the device tested by Eagleworks Lab.
I fail to see how figure 1 serves as a model for the derivation of the thrust equation for EmDrive.QuoteThe significance of this derivation and its agreement with the measurement is not only the possible explanation of the EM Drive operation but also the terrestrial confirmation of existence of the DM including the correctness of the finite size model of the universe from which the DM formulas were obtained.
To me, this paper appears to be a theory of how to generate longitudinal gravitational waves (if such a thing exists) from electromagnetic waves with dark matter particles as the intermediary. Most extraordinary to me is that it introduces a novel "DM model of the universe" (essentially rejecting established theories such as General Relativity and the Standard Model). I fail to see how the EmDrive serves as proof of your DM model of the universe, as the assumptions I take issue with at the beginning of this post are the basis for your derivation. The "anomalous thrust" from the EmDrive doesn't even do a good enough job of confirming EmDrive itself, let alone confirming a new model of the universe.
Gravitational waves are a prediction of General Relativity and do not require the addition of a DM model of the universe.
To my knowledge, what is required for the generation of gravitational waves is a rotating or oscillating mass quadrupole moment.
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#2163 by rfcavity on 23 Jan, 2016 13:13
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Please comment on the theory.
http://gsjournal.net/Science-Journals/%7B$cat_name%7D/View/6323
If a large percentage of EMDrive thrust was caused by gravity waves, then it could be used in reverse. I.e. a gravity wave detector.... Why do some people still remain excited about any in-air tests after seeing these results is honestly beyond me.
In a few words, the reason why people are excited is because this is something they can test themselves, they certainly cannot test by themselves other means of possible far-out space propulsion: they cannot test matter/antimatter propulsion, or an Alcubierre drive, etc. etc.
The science-fiction predictions by Shawyer and White on an EM Drive reactionless drive, including White's discussion of a warp Alcubierre type is probably another motivator. Wouldn't it be nice to be a Zefram Cochrane's in a Star Trek historic warp flight? The last 40+ years after Apollo, in low Earth orbit have been very boring and 2001 was not the Space Odissey we envisioned as children..
I think its fine that people are excited and trying stuff out. As an EM person, the general public so rarely gets excited about anything in the field, this isn't lost on me (although asking people who don't know better for money starts to get iffy for me).
I also get the attraction to space and how repeated promises haven't actually materialized. I did some space stuff on the side during graduate school, comms stuff to make the real experiment run, and it was fun and interesting.
Therein lies the disconnect that I don't completely understand. It is cheaper than ever to get something you made into space. Space has never been more accessible. On top of that many citizen space 'programs' would absolutely die to have people that display the work ethic here on their team. They could be helping send stuff up doing what they already do, without having to disprove decades of experimentation. I dunno.
And if your opinion is proven wrong, what then?
If the EMDrive actually worked I would make a lot of money as my skills would suddenly be highly sought after by large amounts of corporations. -
#2164 by Mulletron on 23 Jan, 2016 13:18
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If it worked by emitting gravitational waves, it could be possible to use two identical EmDrives to communicate too.Please comment on the theory.
http://gsjournal.net/Science-Journals/%7B$cat_name%7D/View/6323
If a large percentage of EMDrive thrust was caused by gravity waves, then it could be used in reverse. I.e. a gravity wave detector. -
#2165 by rfmwguy on 23 Jan, 2016 13:54
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The sleeping Mod awakens -
The polarizing nature of the emdrive project is simple to understand. Both sides have something in common. Its the lack of personal, direct evidence. Its a belief system without personal observation and direct knowledge. Both sides rely on something written by others for the most part.
What confounds me about this is: considering the ramifications of what the emdrive could mean, so many are willing to NOT to check it out for themselves and settle the matter once and for all.
For those accepting it will work...the proof is in your experiment. For those denying it will work...we all get it. Everything you've read and been told says it cannot work. No need to constantly repeat either side of the argument. It works? Show us. It doesn't work? Try it if you've got the skills and resources.
If you don't have the skills or resources, follow those who do but don't repeat yourselves. We all know it shouldn't work and the very few people investing time and money shouldn't have to read negativity page after page after page. The emdrive forum on Reddit is built upon a negative position. They would be happy to have additional posters there with that belief. Here, we try to keep an open mind and civil discussions...and yes, inappropriate posts and posters will be moderated not only by me but by NSF staff who are far more unforgiving than me.
Lets have the experimenters experiment. Help them design better methodology like Mr Li, Glennfish and Dr Rodal who aren't convinced it works either, yet they help. Quite an admirable thing to do IMHO. -
#2166 by Rodal on 23 Jan, 2016 14:34
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Please comment on the theory.
http://gsjournal.net/Science-Journals/%7B$cat_name%7D/View/6323
First, welcome to this forum
0) I checked your expression for the force and it is indeed dimensionally consistent
The following requires further analysis/discussion:
1) The final expression does not seem to have any explicit dependence on the quality factor of resonance (Q), this sets it apart from all other theories (Shawyer, McCulloch and Notsosureofit) that are explicitly linearly dependent on Q
2) The final expression depends linearly on the length of the resonator but there is no explicit dependence on the diameters. Actually, it looks like the expression would work for a perfectly cylindrical resonator (instead of a truncated cone) is that correct?
3)Quote from: Hynecekit is difficult to judge the value of the probability factor ξ for each experiment and if any circularly polarized photons can actually be generated in the given apparatus
, yes the coupling factor ξ appears as a variable factor that may be dependent on geometry, quality of resonance (Q), dielectric inserts, and other parameters, yet its explicit form is unknown up to now
4) It appears that the overall theory backing this up is at odds with General Relativity (I even saw one of your papers related to Kepler's solution and General Relativity ( http://vixra.org/abs/1506.0127 ), and also another one arguing for a steady state Universe instead of the Big Bang (http://vixra.org/author/jaroslav_hynecek)). Hence the overall theory has to be reconciled to be in agreement with all the experimental data we have for our Universe.
5) Here are the proper dimensions of the tested EM Drive by NASA:
Notice that the length is 9 inches = 0.2286 meters instead of L=0.783 m considered in the paper, that is the actual length was 1/3.4 times shorter, this results in a calculated force of 27 microNewtons for 16.92 Watt input, instead of the 91 microNewtons calculated in the paper for L=0.783 m, which is not bad compared to the actual measurement of 91 microNewtons @ 16.9 Watt and of 51 microNewtons @16.7 Watt
EDIT: Those measurements by NASA (91 and 51 microNewtons) were conducted at ambient pressure and appear to be contaminated by thermal effects. NASA's measurements in vacuum, and Tajmar (TU Dresden) experiments in vacuum give significantly smaller Force/Power (see: http://emdrive.wiki/Experimental_Results). Hence your coupling factor ξ may indeed be smaller than one: ξ < 1
6) Your theory giving a larger force for a larger EM Drive is in rough agreement with the other theories giving a larger force for a larger EM Drive because Q (appearing in the other theories) is proportional to the SquareRoot of the dimension (in case the Square Root of the length]. Also, it makes sense that a larger volume of EM Drive should more readily accommodate larger power, which the other theories do not explicitly consider. So, in a few words, all theories agree that the larger the EM Drive, the more efficient it would be.
7) Mulletron has more comments here: https://forum.nasaspaceflight.com/index.php?topic=39004.msg1482027#msg1482027
Thank you for your involvement in this forum
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#2167 by Notsosureofit on 23 Jan, 2016 15:33
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@Rodal (catching up ... the old dielectric notes are scattered, but we left off on this end w/ a 1/4 wave plate as I remember)
NT' = NT(((2p-1)+n)/2p) , where p is the 3rd quantum number. There is also an effect on Q, but I need the complex indices for copper (or silver) and the dielectric at the frequency being used.
Edit: still looking for the cylindrical cavity note ... around here somewhere.. that has the geometrical contribution .. -
#2168 by wallofwolfstreet on 23 Jan, 2016 16:17
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Well in his progress report from just yesterday he writes:
Progress report.
Frustum forming hoops have finally arrived. Not the quality I expected, see the non cleaned up welded joints but they will do.
Also have attached my 1st very manual test setup, which should allow me to explore the frustum resonance, Q, nearby modes, bandwidth and others.
If this simple setup gens thrust, well you will know it here 1st. However that is NOT my objective. I need to get very up close and personal with this frustum, how it behaves and how to obtain a stable (which others have shared is NOT easy to do) high Q TE013 excited mode.
Finger tips and palm still sore from the copper cuts, maybe 1 week or so to be able to try to build the frustum again.
Should add there is no VNA in the drawing as I need to know how the frustum reacts to my amp's output and how the frustum reacts to the 1/2 current loop when serious power is applied. Also when this goes real time best freq tracking and driving the rotary table there will be no VNA involved.
To restate my objective, which is NOT to prove the EmDrive works. Take it as read it works.
To measure the real time relationship, during acceleration, between power supply energy consumed, raw Rf amp energy output, forward Rf amp energy into the frustum, delivered kinetic energy driving rotary table angular acceleration & changes that happen to the frustum during acceleration.
As I stated earlier: 2016 is going to be a very interesting year for EmDrive supporters, skeptics & deniers. It will be interesting to watch as people move from skeptics and deniers to supporters or just disappear as the experimental data destroys any ability to maintain their denial.
Phil
Bold emphasis mine. That post was less than 24 hours ago, so I don't think he is referring to thrust from his own setup. He says he isn't aiming for thrust from this first setup anyway.
EDIT: See Rodal's post below, -
#2169 by Rodal on 23 Jan, 2016 16:28
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Progress report.
Frustum forming hoops have finally arrived. Not the quality I expected, see the non cleaned up welded joints but they will do.
Also have attached my 1st very manual test setup, which should allow me to explore the frustum resonance, Q, nearby modes, bandwidth and others.
If this simple setup gens thrust, well you will know it here 1st. However that is NOT my objective. I need to get very up close and personal with this frustum, how it behaves and how to obtain a stable (which others have shared is NOT easy to do) high Q TE013 excited mode.
Finger tips and palm still sore from the copper cuts, maybe 1 week or so to be able to try to build the frustum again.
Should add there is no VNA in the drawing as I need to know how the frustum reacts to my amp's output and how the frustum reacts to the 1/2 current loop when serious power is applied. Also when this goes real time best freq tracking and driving the rotary table there will be no VNA involved.
To restate my objective, which is NOT to prove the EmDrive works. Take it as read it works.
To measure the real time relationship, during acceleration, between power supply energy consumed, raw Rf amp energy output, forward Rf amp energy into the frustum, delivered kinetic energy driving rotary table angular acceleration & changes that happen to the frustum during acceleration.
As I stated earlier: 2016 is going to be a very interesting year for EmDrive supporters, skeptics & deniers. It will be interesting to watch as people move from skeptics and deniers to supporters or just disappear as the experimental data destroys any ability to maintain their denial.
Phil
Bold emphasis mine. That post was less than 24 hours ago, so I don't think he is referring to thrust from his own setup. He says he isn't aiming for thrust from this first setup anyway.
[/quote]
Coincidentally, "Phil" (same first name as TheTraveller signed his above-quoted NSF post) wrote in his Twitter account, 2 hours ago:QuoteMy 1st EmDrive tests have shown very significant thrust. Need to do more work with local uni before publishing results. Stay tuned.
his previous twit (yesterday) quoted the above-quoted NSF post by TheTraveller (with a sketch of this scale-measuring test):QuoteJan 22
My EmDrive build progress update:
http://forum.nasaspaceflight.com/index.php?topic=39004.msg1481469#msg1481469 …
Note last paragraph.
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#2170 by forgravity on 23 Jan, 2016 18:12
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Just an idea (from a layman point of view)
There have been some tests with dielectrics but has anyone done any experiments with stronger diamagnetic materials (compared to copper) such as bismuth? Bismuth is fairly cheap and it is easily molded. Perhaps someone can clue me in if this would make any difference whatsoever.
Cheers
I recall the discussion about magnetic permeability and the possible use of metglas 2714A, and Todd's suggestion to use it on the large end of the frustum...
http://www.metglas.com/products/magnetic_materials/2714a.asp
as "cheaper" alternative , one could use 99.95% pure iron...
https://en.wikipedia.org/wiki/Permeability_%28electromagnetism%29
Right, yeah I was looking into this a bit and it seems that the permeability or metglas breaks down at higher frequencies. So for EM drive applications (which mostly use 2.45GHz) it seems like a no-go.
99.95% Pure iron seems like a good option. This company here: https://www.americanelements.com/iron-sheet-7439-89-6 sells sheets up to 99.99% (not too sure about the price though)
edit: oxidation may be an issue with this as pointed out below
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#2171 by Rodal on 23 Jan, 2016 18:52
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More information on EM Drive testing
It has has now been posted on Reddit that TT's initialQuoteresults are 10% of predicted
35 mN/kW (vs predicted 389 mN/kW)
Tested on scale, above results average of both directions
Loaded Q = 8700
"Short Pulse 1 sec"
The predicted value (389 mN/kW) is typical of the upper range of Shaywer's results.
The measured force/Power value 35 mN/kW (apparently using a digital scale), although being 10% of that, it is still
0.035 of the upper range of what Yang reported in air
8 times what NASA reported in air under mode shape TM212,
13 times what Iulian Berca reported (also using a scale)
178 times what Dave Distler reported using a teeter-totter balance
213 times what Tajmar (TU Dresden) reported in air
So, although it is a fraction of what Shawyer and Yang have reported, it is several times what other testers have reported
_____________________________________________________________
Due notice should be made in assessing these comparisons that:
* Tajmar's cavity is tiny (2.5 inches long) compared with the other ones, and it is known that is is expected that the smaller the EM Drive, the less efficient the anomalous force will be. Tajmar's cavity was also excited at an extremely low Q (Q=49) and it was overcoupled through a relatively huge waveguide.
* Distler's EM Drive was made with conical walls of perforated copper mesh, and reported as deviating from a conical shape
* Q's, mode shapes, and amount of coupled forward power differs between the different tests
* no photographs of the test setup have yet been reported -
#2172 by X_RaY on 23 Jan, 2016 19:20
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Pure iron is extremely reactive in ambient air due to the 21% oxygen, especially at the outer few µm/mil of the skin. This problem will much bigger at high temperatures in a frustum fired by a magnetron. Like dielectrics it causes a reduction of the cavity Q. Why not try to use ceramic ferrite like Fe2O3 ? It leads to the same effect (high µ_r) but without oxidation/corrosion. It is already oxidized and therefore stable and it is used in commercial microwave absorbers.Just an idea (from a layman point of view)
There have been some tests with dielectrics but has anyone done any experiments with stronger diamagnetic materials (compared to copper) such as bismuth? Bismuth is fairly cheap and it is easily molded. Perhaps someone can clue me in if this would make any difference whatsoever.
Cheers
I recall the discussion about magnetic permeability and the possible use of metglas 2714A, and Todd's suggestion to use it on the large end of the frustum...
http://www.metglas.com/products/magnetic_materials/2714a.asp
as "cheaper" alternative , one could use 99.95% pure iron...
https://en.wikipedia.org/wiki/Permeability_%28electromagnetism%29
Right, yeah I was looking into this a bit and it seems that the permeability or metglas breaks down at higher frequencies. So for EM drive applications (which mostly use 2.45GHz) it seems like a no-go.
99.95% Pure iron seems like a good option. This company here: https://www.americanelements.com/iron-sheet-7439-89-6 sells sheets up to 99.99% (not too sure about the price though)
www.mdpi.com/1996-1944/6/4/1520/pdf
http://anothersample.net/magnetic-and-microwave-absorbing-properties-of-polyaniline-g-fe2o3-nanocomposite
...
Web search for " fe2o3 microwave absorber"
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#2173 by forgravity on 23 Jan, 2016 19:45
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Pure iron is extremely reactive in ambient air due to the 21% of oxygen, especially at the outer few µm/mil of the skin. This problem will much bigger at high temperatures in a frustum fired by a magnetron. Like dielectrics it causes a reduction of the cavity Q. Why not try to use ferrite? It leads to the same effect (high µ_r) but without oxidation/corrosion.Just an idea (from a layman point of view)
Pure iron is extremely reactive in ambient air due to the 21% oxygen, especially at the outer few µm/mil of the skin. This problem will much bigger at high temperatures in a frustum fired by a magnetron. Like dielectrics it causes a reduction of the cavity Q. Why not try to use ferrite, it leads to the same effect (high µ_r) but without the oxidation problem?
There have been some tests with dielectrics but has anyone done any experiments with stronger diamagnetic materials (compared to copper) such as bismuth? Bismuth is fairly cheap and it is easily molded. Perhaps someone can clue me in if this would make any difference whatsoever.
Cheers
I recall the discussion about magnetic permeability and the possible use of metglas 2714A, and Todd's suggestion to use it on the large end of the frustum...
http://www.metglas.com/products/magnetic_materials/2714a.asp
as "cheaper" alternative , one could use 99.95% pure iron...
https://en.wikipedia.org/wiki/Permeability_%28electromagnetism%29
Right, yeah I was looking into this a bit and it seems that the permeability or metglas breaks down at higher frequencies. So for EM drive applications (which mostly use 2.45GHz) it seems like a no-go.
99.95% Pure iron seems like a good option. This company here: https://www.americanelements.com/iron-sheet-7439-89-6 sells sheets up to 99.99% (not too sure about the price though)
I'm reading a bit about ferrite it seems it has similar issues with higher frequencies (like metglas) but I cant find too much solid information about it.
how about cobalt-iron? or ferritic stainless steel?
Nickel is another option but a 12x12" sheet of it is $500
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#2174 by Flyby on 23 Jan, 2016 19:46
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More information on EM Drive testing
The only problem I see with such a listing is that specific thrust seems to depend on the amount of power input and seems to degrade to a certain extend when power is increased.
It has has now been posted on Reddit that TT's initialQuoteresults are 10% of predicted
35 mN/kW (vs predicted 389 mN/kW)
The predicted value (389 mN/kW) is typical of the upper range of Shaywer's results.
The measured force/Power value 35 mN/kW (apparently using a digital scale), although being 10% of that, it is still
0.035 of the upper range of what Yang reported in air
8 times what NASA reported in air under mode shape TM212,
13 times what Iulian Berca reported (also using a scale)
178 times what Dave Distler reported using a teeter-totter balance
213 times what Tajmar (TU Dresden) reported in air
(.....)
fe, between 800W and 2300W, yang's average specific thrust is only 183mN/kW, instead of the peek performance of 1160mN/kW measured at 200W...
It seems very hard to make an accurate linear extrapolation , if you take this into account.
I realize they are the only info bits we have, but we risk comparing apples with oranges, no?
Ideally, we should be comparing specific thrust based upon the same input power.
The introduction of so many different variables (different shapes, different materials, different frequencies, different modes, different power input, etc...) between all those test setups makes it incredibly hard to compare all those tests on a fair basis.
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#2175 by Mulletron on 23 Jan, 2016 19:51
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So I went back to look for when @Notsosureofit began talking about entropy because I didn't understand where he was going with the application thereof. I think I get it now reading his posts from thread 2. I guess I wasn't paying attention or not participating. His "strained photon distribution" sounds like the same thing as the 3am quadrupole mass distribution post from a few days ago.
http://forum.nasaspaceflight.com/index.php?topic=36313.msg1373471#msg1373471
http://forum.nasaspaceflight.com/index.php?topic=36313.msg1373509#msg1373509
I'm going to hit the forum up with a pretty ridiculous sounding thought experiment about this soon. -
#2176 by Rodal on 23 Jan, 2016 19:56
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More information on EM Drive testing
The only problem I see with such a listing is that specific thrust seems to depend on the amount of power input and seems to degrade to a certain extend when power is increased.
It has has now been posted on Reddit that TT's initialQuoteresults are 10% of predicted
35 mN/kW (vs predicted 389 mN/kW)
The predicted value (389 mN/kW) is typical of the upper range of Shaywer's results.
The measured force/Power value 35 mN/kW (apparently using a digital scale), although being 10% of that, it is still
0.035 of the upper range of what Yang reported in air
8 times what NASA reported in air under mode shape TM212,
13 times what Iulian Berca reported (also using a scale)
178 times what Dave Distler reported using a teeter-totter balance
213 times what Tajmar (TU Dresden) reported in air
(.....)
fe, between 800W and 2300W, yang's average specific thrust is only 183mN/kW, instead of the peek performance of 1160mN/kW measured at 200W...
It seems very hard to make an accurate linear extrapolation , if you take this into account.
I realize they are the only info bits we have, but we risk comparing apples with oranges, no?
Ideally, we should be comparing specific thrust based upon the same input power.
The introduction of so many different variables (different shapes, different materials, different frequencies, different modes, different power input, etc...) between all those test setups makes it incredibly hard to compare all those tests on a fair basis.
My post also included the following (which I repeat again for emphasis):Quote from: RodalDue notice should be made in assessing these comparisons that:
* Tajmar's cavity is tiny (2.5 inches long) compared with the other ones, and it is known that is is expected that the smaller the EM Drive, the less efficient the anomalous force will be. Tajmar's cavity was also excited at an extremely low Q (Q=49) and it was overcoupled through a relatively huge waveguide.
* Distler's EM Drive was made with conical walls of perforated copper mesh, and reported as deviating from a conical shape
* Q's, mode shapes, and amount of coupled forward power differs between the different tests
* no photographs of the test setup have yet been reported
In other words, yes, the fact that * Q's, mode shapes, and amount of coupled forward power differs between the different tests, and even gross difference in size (Tajmar) and material (perforated copper sheet for Distler with another shape), and that Yang and Shawyer are "upper range" had been duly noted
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#2177 by rfmwguy on 23 Jan, 2016 22:10
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Sorry compadres, been offline except for one post today. Nsf staff advised me some posts were deleted. Didnt see them but our hosts have final say and have no issue with that. Yep, sometimes life gets in my way.
p.s. They may call this a blizzard on the east coast...up here in NE Ohio, we call it January
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#2178 by DIYFAN on 23 Jan, 2016 22:28
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Scaling for the difference in RF power between their forward and reversed vacuum test, and assuming the most optimistic case where the null force is exactly the same between the 2 orientations, their "thrust" value is then something like ~25 uN (with 15 uN of null force) @30W. Now, given how
biasedpassionately they're approaching this task, I will believe in this number when someone else is able to verify it, but this is not even the point. The point is that they have just shown that their original ~230 uN (scaling to 30W) of "thrust" in air, for which they even had some undisclosed QV model and predictions is basically all gone. They have also just shown that there does indeed exist some interesting (but most certainly non-anomalous) air-related effects which result in (relatively large) observed forces changing almost perfectly in sync with the applied RF pulse. (So everyone testing in air and claiming "thrust" has to account for this). Why do some people still remain excited about any in-air tests after seeing these results is honestly beyond me.
The EW vacuum tests suffered from the lack of vacuum-compatible RF amps. The results, while interesting, were not conclusive due to component failures under vacuum conditions. Here, Paul March talks about wanting to get some vacuum compatible RF amps, but that they are ~$6,500 each, and unlikely to get them until more proof could be provided to NASA management.
https://forum.nasaspaceflight.com/index.php?topic=36313.msg1364355#msg1364355
A classic chicken and egg. The NSF shortly thereafter started discussing the possibility of crowd-funding the EW effort, but that was shot down pretty quickly as not feasible under NASA's rules.
So to draw any firm conclusions about the vacuum results and "Why do some people still remain excited about any in-air tests after seeing these results is honestly beyond me" seems premature, IMHO. -
#2179 by zen-in on 23 Jan, 2016 22:29
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I hope we will see more data from experiments. While I am a non-believer I am still interested in seeing new results. My skepticism comes from several years of building stuff and finding out it doesn't work the way I had planned. But, like the object of Kipling's famous poem, I pick myself up and start over again. The experience of building something and testing an idea is valuable in its own right. If you keep doing it enough times you will eventually discover something new. That is the goal.
