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#1920
by
Rodal
on 04 May, 2016 14:54
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As Dave correctly states, the new particle that may have been found (is that what your post was about?) if real and not an experimental artifact appears at 750 Giga Electron Volts.
Mass-energy of a W boson (80.4 GeV)
Mass-energy of a Z boson (91.2 GeV)
Mass-energy of the Higgs Boson (125.1 GeV)
Mass-energy of a 2.45Ghz Microwave photon (1.0132-5 eV)
To play devil's advocate somebody could advocate coupling to such a supermassive particle. However I fail to see how coupling could take place at microwave frequencies and ~ 1 kW. Perhaps somebody can speculate on how coupling would be possible, even with a 2 photon process
As of 2012, the best constraint on the elastic photon–photon scattering cross section belongs to PVLAS, which reports an upper limit far above the level predicted by the Standard Model:
http://arxiv.org/abs/1201.2309
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#1921
by
SeeShells
on 04 May, 2016 15:23
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As Dave correctly states, the new particle that may have been found (is that what your post was about?) if real and not an experimental artifact appears at 750 Giga Electron Volts.
Mass-energy of a W boson (80.4 GeV)
Mass-energy of a Z boson (91.2 GeV)
Mass-energy of the Higgs Boson (125.1 GeV)
Mass-energy of a 2.45Ghz Microwave photon (1.0132-5 eV)
Shouldn't be reading this when I'm punchy, been up all night working.
Have a question here when we are dealing with something on the order of >10^38 photons within the frustum cavity how does that effect those numbers.
ref.
https://answers.yahoo.com/question/index?qid=20101018074723AADYY6YPlus I'm increasing the energy by the Q factor.
Off to get some sleep.
Shell
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#1922
by
Rodal
on 04 May, 2016 15:32
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As Dave correctly states, the new particle that may have been found (is that what your post was about?) if real and not an experimental artifact appears at 750 Giga Electron Volts.
Mass-energy of a W boson (80.4 GeV)
Mass-energy of a Z boson (91.2 GeV)
Mass-energy of the Higgs Boson (125.1 GeV)
Mass-energy of a 2.45Ghz Microwave photon (1.0132-5 eV)
Shouldn't be reading this when I'm punchy, been up all night working.
Have a question here when we are dealing with something on the order of >10^38 photons within the frustum cavity how does that effect those numbers.
ref. https://answers.yahoo.com/question/index?qid=20101018074723AADYY6Y
Plus I'm increasing the energy by the Q factor.
Off to get some sleep.
Shell
The best way is to forget about the word “particle” in the sense that we see objects around us. Instead think of every particle as both a particle and wave. Therefore think of it as
a disturbance in a field. A ripple in a field, one that can travel through space and time, like a clear musical tone, or a nice wave traveling through the water surface.
Thus, instead of thinking about total energy, think about
energy density associated with that small ripple taking place in the volume of space.
As to all those photons, well, there are not that many when you think how much space there is in between them, think of them as a photon gas
https://en.wikipedia.org/wiki/Photon_gas . If thinking about their interaction, think of
two photon physics...
https://en.wikipedia.org/wiki/Two-photon_physics
As to "increasing the energy with Q" think of the contradiction that was addressed by Zen-In now, and was addressed long ago by Todd DeSiato Warp Tech: if you are going to take energy away to accelerate the EM Drive, that disturbs the Q. So,
how are you going to be extracting energy, and at the same time positing constant acceleration at constant power input?If that extra energy comes from the Quantum Vacuum as posited by Dr. White, well, then as also per Dr. White the best "thrust" may NOT be necessarily with mode shapes that give maximum Q. Same when using Prof. Woodward's model
Shawyer's model that this can be explained by Maxwell's equations and Newton's laws is not viable: it goes against energy conservation.
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#1923
by
Gilbertdrive
on 04 May, 2016 17:01
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Dr Rodal, I am perplexed by your willingness to declare that the recently reported Yang results nullify all of her previous results. By Yang changing from an Magnetron, presumably powered by an AC supply, to Solid State RF source powered by DC, it seems that more then enough experimental conditions have changed to make these different experiments beyond the changing of measurement techniques...
Upon further thought prompted by your post, I have to logically conclude what you bring up is an argument for nullification, not only of Yang's tests but also of Shawyer's tests:
as I have shown previously taking the threshold for Yang's instrument to be +/- 3mN @ 220 Watts, besides Yang's tests, the following tests by Shawyer are way above this threshold of detection:
Shawyer DEMONSTRATION (uses magnetron)
Shawyer FLIGHT THRUSTER (does not use a magnetron)
1) IF THE MAGNETRON IS NECESSARY TO PRODUCE THRUST
It is not possible that both Shaywer DEMONSTRATION and FLIGHT THRUSTER are true. At least one of them must be false: the FLIGHT THRUSTER, since it has no magnetron.
So, this would mean that Shawyer's FLIGHT THRUSTER is false. It also implies that all of Shawyer's latest EM Drive's that do not use a magnetron are also false, that claim levels of force/InputPower above Yang's threshold level.
2) IF THE MAGNETRON IS NOT NECESSARY TO PRODUCE THRUST
Then it is possible that both Shaywer DEMONSTRATION and FLIGHT THRUSTER are true.
However, this is in flagrant contradiction with Yang's 2016 tests with batteries and no magnetron, showing no thrust (above the threshold).
Since the DEMONSTRATION and FLIGHT THRUSTER are above the threshold of detection, the way to resolve this contradiction is to conclude that the Shawyer DEMONSTRATION and FLIGHT THRUSTER are both false for other reasons (for example: the use of power cords instead of batteries)
It could also be that all of Shawyer's and Yang tests are null because they do not use a polymer insert, because they never understood that the function of NASA's polymer insert is as a piezoresistive or electrostrictive material, and never as a dielectric. In other words because they do not understand Woodward's Mach Effect, and the role of the polymer insert. (*)
There are other solutions (for example that all of Shawyer's and Yang's EM Drive tests are atrocious, all false, due to using teeter-totters, scales, power cords, lack of error analysis, thermal convection because they do not use a vacuum chamber, etc.). The above appear to be the least pathological, (there are other extreme pathological solutions involving conspiracy theories, etc).
Maybe somebody can come with a solution that is not pathological that does not involve contradictions?
____________
(*) Maybe the Hackaway tiny battery-powered-EM-Drive positive results with the polymer insert are hinting in this direction?
Hello. I am lurking since thread 3, and I am very impressed with the quality of the reflexion on these threads.
I may have a possible answer to your question, Dr Rodal, but before, does somebody know if Shawyer uses Solid State generators with non superconducting emdrives ?
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#1924
by
zen-in
on 04 May, 2016 17:20
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...
While Q multiplication does work with ruby/yag lasers I have doubts a high Q (Q > 5000) is attainable in a fustrum or that any increase in Q will produce more thrust. There is a basic contradiction there. A very high Q means almost no power during each wave of the RF is leaving the fustrum. So it is another case of free energy. Historically experimenters who have quoted a high Q for their fustrum used a questionable method of calculation or used a simulation program. Yang has retracted her earlier Q value. There has been a lot of discussion on this subject in this forum and unless I am mistaken the high values of Q some DIY experimenters have reported were derived from a simulation program. Both methods produce a non-realistic value. There is a physical definition of Q. When Q is measured correctly these unrealistic high values are not seen.
It is my understanding that high quality linear accelerators can achieve Q exceeding 10^9. Is there any reason why that cannot be done for an emdrive? Providing someone is willing to pay for it ...
We may be talking apples and oranges here. Can you show us a reference to this? No amount of money can change the laws of physics.
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#1925
by
Rodal
on 04 May, 2016 17:28
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...
While Q multiplication does work with ruby/yag lasers I have doubts a high Q (Q > 5000) is attainable in a fustrum or that any increase in Q will produce more thrust. There is a basic contradiction there. A very high Q means almost no power during each wave of the RF is leaving the fustrum. So it is another case of free energy. Historically experimenters who have quoted a high Q for their fustrum used a questionable method of calculation or used a simulation program. Yang has retracted her earlier Q value. There has been a lot of discussion on this subject in this forum and unless I am mistaken the high values of Q some DIY experimenters have reported were derived from a simulation program. Both methods produce a non-realistic value. There is a physical definition of Q. When Q is measured correctly these unrealistic high values are not seen.
It is my understanding that high quality linear accelerators can achieve Q exceeding 10^9. Is there any reason why that cannot be done for an emdrive? Providing someone is willing to pay for it ...
We may be talking apples and oranges here. Can you show us a reference to this? No amount of money can change the laws of physics.
He must be talking superconducting cavities...
Typical Q values for normal conducting cavities in linear accelerators are between 10^3 to 10^5
Typical Q values for superconducting cavities in linear accelerators are between 10^7 to 10^11
See, for example
https://arxiv.org/ftp/arxiv/papers/1303/1303.6552.pdfCERN School:
https://cdsweb.cern.ch/record/503603/files/CERN-2004-008.pdfTAKE A LOOK AT THE
DROP OF Q WITH ACCELERATION FIELD: THERE IS A LIMIT !!!!!
(credit for image: Wikipedia)
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#1926
by
rfmwguy
on 04 May, 2016 17:40
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My understanding is that as a result of the exchange, a useful conclusion was agreed to: that the addressed experiment cannot be compared to Yang's latest experimental report, including her uncertainty threshold of +/- 3 mN .
I don't disagree. My comment meant to imply "taken out of context, that's the most obscure possible..."
Why publish any results in the first place if they show an unequivocal confirmation of significant thrust? Their goal in that case would be to minimize disclosure. And anyway the likelihood that Yangs' first results were valid has always been low. No one has replicated those results and there is no generally accepted theory that explains this claimed effect.
I didn't say she DID falsify the second data, I just said it's plausible. I also acknowledged that her first results were outside the realm reported by others.
My Conspiratorial scenario is that she published her first paper in good faith as an academic / scientist and it took the ChiCom machine a little while to spool up as to the possible implications. When the Machine figured it out, they directed her to chaff while appropriating the research for "national security" purposes.
Again. I'm not even accusing Yang of this. Just saying it's a plausible scenario. 
edit:... "plausible on the surface." My understanding of the math behind all this is limited enough that people like (cough cough Rodal cough) e see right through my scenario. 
Mod note - Its best to leave this as "it is what it is" and take it on face value. Its certainly possible its disinformation, but we'll never really know, nor are our threads a place we can tackle it. On face value, they tried to replicate and failed to do so and therefore the Chinese Institution NWPU is out of the emdrive project. This is almost a certainty with Yang's retirement.
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#1927
by
Rodal
on 04 May, 2016 18:13
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...Hello. I am lurking since thread 3, and I am very impressed with the quality of the reflexion on these threads.
I may have a possible answer to your question, Dr Rodal, but before, does somebody know if Shawyer uses Solid State generators with non superconducting emdrives ?
1) Credit goes to Chris Bergin for providing a moderated forum where only civil discourse is allowed
2) I am intrigued by your possible answer. I will withhold speculation on what Shawyer does and does not use as his reports have never been crystal-clear to me, and there are people in the forum that have read more about what Shawyer has or has not used. TheTraveller has posted that he has communicated with Shawyer and attributes to Shawyer that Shawyer did not use a magnetron for Boeing's flight thruster, which is consistent with its reported frequency of 3.85 GHz. Shawyer writes:
The thruster is designed to be powered from existing flight qualified TWTAs, which are driven from a dual redundant frequency generator unit (FGU) The FGU includes a frequency control loop using feedback signals from the thruster, as shown below in the functional block diagram.
Shawyer's Demonstrator, on the other hand, is reported to have used a magnetron which is consistent with the reported frequency of 2.45 GHz, as most common magnetrons (because of home microwave ovens) have that frequency.
3) I would encourage you to post your possible answer as nobody may really know precisely what Shawyer uses, and it would be interesting to know what you propose regardless.
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#1928
by
Gilbertdrive
on 04 May, 2016 19:49
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I am afraid that my first message could suppose that I had something great, and that my possible solution would seems to be disapointing.
I would suggest (following your 2 first possible solutions)
3: The magnetron is not necessary to produce thrust, but other parameters have to be changed to get thrust without a magnetron. Sawyer superconducting emdrives have, for sure, many differences with his classical emdrive. Shawyer himself maybe unaware of the different parameters that make work his next emdrive with a solid state RF source. And, Yang, using a “classical” emdrive of the preceding generation, with a solid state RF source could not get a positive result.
That is why I was asking if Shawyer had ever used a non superconducting emdrive with solid state. But, if I understand Correctly, the Boeing Flight Thruster is a non superconducting emdrive, with solid state.
We are not sure that he and Pr. Yang communicated again after the first Pr. Yang Publication. If Pr Yang just replaced the magnetron by a Solid State without getting new data from Shawyer since the first build, the other parameters maybe the issue.
If I have correctly understood, the new Yang setup, with the external power and the bias of the heating wire, gave a force or 8-10mN. If I use the table on the wiki, for 220W, it means aroung 45mN/Kw
It is already very far from the 160 to 270mN/Kw of the preceding setup, before the elimination of the wire bias.
So, it seems that a parameter (maybe the replacement of the magnetron by Solid state, maybe something else) was very different between the 2 builds, and decreased greatly the force. So I am afraid that, once again, we do not have enough data to conclude on the nullification of the Shawyer experiments. But, IMHO, it would confirm that Shawyer data is not easy to reproduce, even with the explanation of Shawyer himself. Maybe it is because Shawyer results are an artifact, maybe because of his poor capacity to understand, and, or, explain, what is important in his setup.
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#1929
by
Rodal
on 04 May, 2016 20:49
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In a long post here:
http://forum.nasaspaceflight.com/index.php?topic=39214.msg1526577#msg1526577I prove that:
STRESS AT ALL INTERNAL SURFACES FOR TE0np MODES
* all shear stress components are zero, and hence the stress field is a principal stress
* the stress is compressive
* the electric vector field is zero at all internal surfaces
* Coulomb's pressure and the electrostatic pressure are zero
* the stress is entirely due to the energy density
* the stress is entirely due to the magnetic component parallel to the surfaceThe above applies to the mode shapes used in the EM Drive experiments that have claimed the highest force/InputPower.
Prof. Yang has used TE
012 mode shapes in her experimental claims.
Shawyer has used mode shape TE
012 in his Demonstrator experimental claim and reportedly used mode shape TE
013 (according to NSF user TheTraveller) in his Boeing Flight Demonstrator experimental claim.
NASA's reported experiment with the highest force/InputPower has involved mode shape TE
012.
Shawyer's hypothesis that there is no pressure on the side walls is proven incorrect. Shawyer is wrong: there is pressure, and hence a force component on the side walls of a truncated conical cavity with spherical ends:
this pressure is entirely due to the magnetic field component parallel to the wall. This pressure has nothing to do with the electric field components.
STRESS AT ALL INTERNAL SURFACES FOR TM0np MODES
* all shear stress components are zero, and hence the stress field is a principal stress
* the stress is due to two components: a compressive component due to the magnetic energy density and a tensile component due to the electrostatic pressure
* the compressive stress is entirely due to the magnetic component parallel to the surface, in the transverse (azimuthal) direction
* the tensile stress component is entirely due to the electric field component perpendicular to the surface
* the stress integrated over the surface, the force, is compressive , in other words, the magnetic energy density effect predominates over the electrostatic pressure. The stress can have small tensile regions, where the electrostatic pressure exceeds the magnetic energy density.
Again, Shawyer's hypothesis that there is no pressure on the side walls is proven incorrect. Shawyer is wrong: there is pressure, and hence a force component on the side walls of a truncated conical cavity with spherical ends.
The proof only uses the well known boundary conditions for the electromagnetic fields and the mode shapes that have been verified in countless FEKO, and COMSOL computer runs, exact solutions, as well as the only EM Drive experiment that has experimentally verified a mode shape (NASA's verification of mode shape TM212, Shaywer and Yang never reported a single verification of mode shapes).
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#1930
by
zen-in
on 04 May, 2016 21:48
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I didn't say she DID falsify the second data, I just said it's plausible.
...
...
Again. I'm not even accusing Yang of this. Just saying it's a plausible scenario.
edit:... "plausible on the surface." My understanding of the math behind all this is limited enough that people like (cough cough Rodal cough) probably see right through my scenario.
When you say it is plausible that Dr. Yang falsified an experiment you are implying that she is a dishonest researcher. If you don't have any proof Dr. Yang falsified an experiment you should not even make that statement. I think Dr. Yang has been very honorable and professional by re-doing the experiment and retracting her earlier claims. This happens every now and then and should not be construed to mean there has been deceit and it is wrong to even speculate on that matter. I think you owe Dr. Yang an apology for implying there was some dishonesty in her work. After you have done that I would hope that if you are unable to elevate your contributions to this forum you will leave.
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#1931
by
Rodal
on 04 May, 2016 23:09
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Yes Zen-In, Dr. Yang is to be congratulated for being so honest. So is RFPlumber, a DIY builder who had the honesty and courage to report his null results. Also California Polytechnic State Univ., San Luis Obispo, Zeller, Kraft, Echols with their cylindrical cavity test. It takes courage because most people, naturally will be looking for positive results, (who isn't ?) and not for negative results. We all like to receive good news in the morning and not start with bad news, thus those that report negative results are more likely to meet indifference or worse, while those that report positive results will naturally meet with optimism. I also would like to start the morning and see that the EM Drive is a reality and that we can now all go to the Moon and Europa as easy as it looked in 2001 A Space Oddysey.
But imagine what technology would be like if only positive results would be reported and negative would be silenced? We would all be lost, as generations of well-motivated people would be condemned to waste their lives investigating bad roads instead of new unexplored roads.
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#1932
by
Gilbertdrive
on 04 May, 2016 23:14
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Dr Rodal, I entirely agree with your statement, and share your analysis on wrong shawyer hypothesis that there is no pressure on the side walls. Also, I fully agree with the fact that shawyer model, using Maxwell's equations and Newton's laws is not viable. It remains that it is still possible that his experiments shows a real anomalous force, that would be in that case hard to reproduce, because he explains it by a wrong theory.
Also, I notice that the word falsified is used here in different cases.
When Dr Rodal uses falsify, it means proove that something is false. Falsify Shawyer theory means proove that Shawyer theory is false. So, falsify is part of the normal science work.
The debate between Zen-In and JaimeZX about falsification was around to make a false proof, report false mesures, etc. It is another use of the word. Like for a falsified passeport.
If I have correctly understood the context, when Dr Rodal tells us that Shawyer's hypothesis that there is no pressure on the side walls is entirely falsified, it means it has be proven as false. It does not means that anybody was dishonest. I hope that everybody here is aware of these usage of the same word for two different things, so that there is no misunderstanding.
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#1933
by
Rodal
on 04 May, 2016 23:18
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Dr Rodal, I entirely agree with your statement, and share your analysis on wrong shawyer hypothesis that there is no pressure on the side walls. Also, I fully agree with the fact that shawyer model, using Maxwell's equations and Newton's laws is not viable. It remains that it is still possible that his experiments shows a real anomalous force, that would be in that case hard to reproduce, because he explains it by a wrong theory.
Also, I notice that the word falsified is used here in different cases.
When Dr Rodal uses falsify, it means proove that something is false. Falsify Shawyer theory means proove that Shawyer theory is false. So, falsify is part of the normal science work.
The debate between Zen-In and JaimeZX about falsification was around to make a false proof, report false mesures, etc. It is another use of the word. Like for a falsified passeport.
If I have correctly understood the context, when Dr Rodal tells us that Shawyer's hypothesis that there is no pressure on the side walls is entirely falsified, it means it has be proven as false. It does not means that anybody was dishonest. I hope that everybody here is aware of these usage of the same word for two different things, so that there is no misunderstanding.
Yes, it is a word routinely used in mathematics, as when mathematically falsifying a hypothesis, and I never dreamed that it could be misinterpreted.
But in this forum, which is read by many non-mathematicians, it would be better if when I have a chance I change it to "nullify". But first I have to go for a run
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#1934
by
otlski
on 04 May, 2016 23:40
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My next build is in progress.
The flat & spherical end plate frustum is being manufactured to very high physical tolerance and polish standard as recommended by Roger Shawyer. It is being machined from a solid block of copper, highly polished, then silver and gold plated. Min sidewall and end plate thickness are 6mm. The frustum can be fitted with either flat or spherical end plates and can operate internally at high vac or be filled with various gases at adjustable pressure as the end plate to flange interface will form a high pressure & high vac rated seal. This frustum will basically look like a bigger Flight Thruster. Not cheap, expected final cost around $7k. I will visit the manufacturer to run tests before acceptance.
The 0.4N/kW rated S band thruster will be driven initially by a wide freq range 100W Rf amp that has the ability to control Rf output power over a 31dB range and provides real time forward & reflected power output. Work is also ongoing to develop an integral smart 250Wrf module that can be installed in multiples on the thruster, if higher than 100mN of reaction force generation is required. Max thruster power should be around 2.5kWrf or 1,000mN of reaction force generation.
Both static and dynamic reaction force generation will be monitored.
When a reaction force generation level of at least 20mN has been achieved and expected rotation of the rotary test table in a high vac has been achieved the data and video will be presented via YouTube.
Following that successful result, a business entity will be formed and potential customers will be invited to view, inspect & do their own tests on our in house test setup as part of their order process.
My next post here will be with the YouTube link and company contact details.
Good luck with the tests. Please provide the gross MOI of the test apparatus and please show more than one revolution in the video.
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#1935
by
zen-in
on 04 May, 2016 23:51
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Dr Rodal, I entirely agree with your statement, and share your analysis on wrong shawyer hypothesis that there is no pressure on the side walls. Also, I fully agree with the fact that shawyer model, using Maxwell's equations and Newton's laws is not viable. It remains that it is still possible that his experiments shows a real anomalous force, that would be in that case hard to reproduce, because he explains it by a wrong theory.
Also, I notice that the word falsified is used here in different cases.
When Dr Rodal uses falsify, it means proove that something is false. Falsify Shawyer theory means proove that Shawyer theory is false. So, falsify is part of the normal science work.
The debate between Zen-In and JaimeZX about falsification was around to make a false proof, report false mesures, etc. It is another use of the word. Like for a falsified passeport.
If I have correctly understood the context, when Dr Rodal tells us that Shawyer's hypothesis that there is no pressure on the side walls is entirely falsified, it means it has be proven as false. It does not means that anybody was dishonest. I hope that everybody here is aware of these usage of the same word for two different things, so that there is no misunderstanding.
I interpreted JaimeZX's use of the word falsify in the context of his conspiracy theory that implies Dr. Yang did something dishonest at the behest of the Chinese govt. There is no proof that any of this occurred and I believe we should all assume Dr. Yang has done her work honestly. When experimental results falsify an hypothesis that is a different matter and I would say that is a more correct use of the word since there is no ambiguity. I find it curious that someone would invoke a conspiracy theory to reject this latest experiment, despite the fact that it is well presented while no one has challenged other experimental results that have been claimed where there has been no data, video of the experiments, or even photographs of the apparatus.
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#1936
by
zen-in
on 05 May, 2016 05:25
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My next build is in progress.
The flat & spherical end plate frustum is being manufactured to very high physical tolerance and polish standard as recommended by Roger Shawyer. It is being machined from a solid block of copper, highly polished, then silver and gold plated. Min sidewall and end plate thickness are 6mm. The frustum can be fitted with either flat or spherical end plates and can operate internally at high vac or be filled with various gases at adjustable pressure as the end plate to flange interface will form a high pressure & high vac rated seal. This frustum will basically look like a bigger Flight Thruster. Not cheap, expected final cost around $7k. I will visit the manufacturer to run tests before acceptance.
The 0.4N/kW rated S band thruster will be driven initially by a wide freq range 100W Rf amp that has the ability to control Rf output power over a 31dB range and provides real time forward & reflected power output. Work is also ongoing to develop an integral smart 250Wrf module that can be installed in multiples on the thruster, if higher than 100mN of reaction force generation is required. Max thruster power should be around 2.5kWrf or 1,000mN of reaction force generation.
Both static and dynamic reaction force generation will be monitored.
When a reaction force generation level of at least 20mN has been achieved and expected rotation of the rotary test table in a high vac has been achieved the data and video will be presented via YouTube.
Following that successful result, a business entity will be formed and potential customers will be invited to view, inspect & do their own tests on our in house test setup as part of their order process.
My next post here will be with the YouTube link and company contact details.
That's a very good price for the Copper machining. I'm sure the shop that quoted that price will be losing money.
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#1937
by
spupeng7
on 05 May, 2016 05:33
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...
While Q multiplication does work with ruby/yag lasers I have doubts a high Q (Q > 5000) is attainable in a fustrum or that any increase in Q will produce more thrust. There is a basic contradiction there. A very high Q means almost no power during each wave of the RF is leaving the fustrum. So it is another case of free energy. Historically experimenters who have quoted a high Q for their fustrum used a questionable method of calculation or used a simulation program. Yang has retracted her earlier Q value. There has been a lot of discussion on this subject in this forum and unless I am mistaken the high values of Q some DIY experimenters have reported were derived from a simulation program. Both methods produce a non-realistic value. There is a physical definition of Q. When Q is measured correctly these unrealistic high values are not seen.
It is my understanding that high quality linear accelerators can achieve Q exceeding 10^9. Is there any reason why that cannot be done for an emdrive? Providing someone is willing to pay for it ...
We may be talking apples and oranges here. Can you show us a reference to this? No amount of money can change the laws of physics.
He must be talking superconducting cavities...
Typical Q values for normal conducting cavities in linear accelerators are between 10^3 to 10^5
Typical Q values for superconducting cavities in linear accelerators are between 10^7 to 10^11
See, for example https://arxiv.org/ftp/arxiv/papers/1303/1303.6552.pdf
CERN School: https://cdsweb.cern.ch/record/503603/files/CERN-2004-008.pdf
TAKE A LOOK AT THE DROP OF Q WITH ACCELERATION FIELD: THERE IS A LIMIT !!!!!
(credit for image: Wikipedia)
Yes, wot he sais...
Thanks Dr R.
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#1938
by
TheTraveller
on 05 May, 2016 05:51
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... Not cheap, expected final cost around $7k....
That's a very good price for the Copper machining. I'm sure the shop that quoted that price will be losing money.
Asian build.
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#1939
by
TheTraveller
on 05 May, 2016 05:56
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My next build is in progress.
What were the results with your previous build?
~8mN, unloaded Q ~16,000, forward Rf power ~95W.
BTW Mike McCulloch in personal email predicted 2.8mN,
Shawyer's equation predicted 6.7mN,
I measured 8mN.
My direct measurement of unloaded Q was probably a bit low. Note I did say direct measurement of unloaded Q, which does not involve measuring -3dB bandwidth. Doing direct unloaded Q measurement eliminates the issue surrounding how to measure loaded Q using various bandwidth methods.
Simple to calculated unloaded Q by determining the 1 TC cavity fill time and from that determine the cavity unloaded Q.
Other than Mike's calculation none of the above is new information.
