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#2240 by Tellmeagain on 26 Jan, 2016 01:10
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This thread is about the EM Drive progress. It is being used by several NASA folk (they aren't using the social media sites, per their request for me to keep what is a fringe subject alive on this site) ahead of the big tests that are coming at its next NASA center very soon. They are using this site's threads on this because of the history of the subject's progress, the crowdsourcing efforts and the quick catch up they can do on a bi-daily (or whatever) basis, where they don't have to trawl through 500 "Iz got me toaster to vibrate across me kitchen and anyone who says dat's not propellantless thrust can kiss my as*! and I'm LEAVING if u says dat!" posts because of the forum rules for the entire site's forum.
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I think I did not miss this big news. Let's see -
#2241 by Tellmeagain on 26 Jan, 2016 01:31
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She is not in school of aeronautics , but in school of astronautics. She is still listed in the Chinese version of the professor list there,
list: http://hangtian.nwpu.edu.cn/szdw/jslb.htm
Her page: http://hangtian.nwpu.edu.cn/info/1229/6335.htm
Thanks for the correction ! I corrected my posts accordingly (to the extent of my recollection).
NSF User TheUberOverLord ( http://forum.nasaspaceflight.com/index.php?topic=39004.msg1482910#msg1482910 ) suggestedQuotewhether would it not still be possible to potentially get names and contact information of those that did editorial reviews of Prof. Yangs papers and then afterwards attempt to contact those individuals avoiding the subject of why funding ceased.
As I understand you are fluent in the Chinese language (and you linked to pages in Chinese language for Prof. Juan Yang's position at her University), and I am not, you may be interested in following up TheUberOverLord's suggestion.
Her funding must not be from the university but from outside of the university. This is because I do not think there exists university funded research (except for seed funding for new PI's) in China. Journal paper reviewers usually are not related to the project review so I do not think it is useful to contact them. The reason why her funding was not extended was given by user "oyzw" that the project reviewers did not like her using air-suspension table and also because the concept conflicted with established physics.
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#2242 by A_M_Swallow on 26 Jan, 2016 01:47
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I would like to pose this question to those more familiar with peer-reviewed journal publications...
No. I can tell you there is NO such requirement. It is up to the Peer Reviewers to review the papers very carefully and find errors, etc. There is no such thing as "agreed upon theory" anyway, what there is, is a scientific method. There are so many examples, but the way that Einstein, Feynmann, von Neumann, Heissenberg, Dirac and others got famous is to develop a new theory, instead of working on an old agreed-upon theory. Actually, in my experience, reputable journals abhor "review articles of agreed-upon theories". You are expected to come up with something new, and not to work on something old (even worse is just to review something old).
It is my understanding that the best papers in the best journals always require an agreed upon THEORY before publishing occurs. IOW, do you think EW's paper in the works will have to nail down the theory BEFORE it goes to print? If so, the theory must be much further along than I assume. As of now, its all up in the air in my estimate.
Inquiring minds want to know...well, I do anyway...
What is a no-no is to work to try to publish a paper with a theory where the mathematics are wrong, or where the author cannot adequately answer questions regarding the mathematics and physics behind their arguments.
Concerning publication of the EW article, it all depends (entirely) on what journal they intend to publish. There are journals that concentrate only on experiments. There are journals that concentrate on theory and there are journals that deal with both. There are so many peer-reviewed journals, that it is really not hard to get an article published in a peer-reviewed journal. It is hard to get published in the highly ranked (by citation index) journals, easy to get published on the low-citation index journals and low readership journals.
Concerning time for peer-review it is perfectly normal for this process to take several months, even a long time, nothing unusual.
Do you know what journal they are intending to publish their article on?
I think that there are 3 types of papers will be published about the EMDrive.
1. Reporting the experimental results and equipment.
2. EMDrive theory and equations based on the experiments plus Maxwell's equations.
3. Reconciling the EMDrive with the physics of Newton and Einstein. For instance the conversion of electricity/energy into propulsion without propellant appears to break the Conservation of Moment rules.
Since any current theory will be wrong or at least incomplete publishing theory and experiments separately will save problems when citing half a paper. -
#2243 by ThinkerX on 26 Jan, 2016 03:22
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Quote
This thread is about the EM Drive progress. It is being used by several NASA folk (they aren't using the social media sites, per their request for me to keep what is a fringe subject alive on this site) ahead of the big tests that are coming at its next NASA center very soon. They are using this site's threads on this because of the history of the subject's progress, the crowdsourcing efforts and the quick catch up they can do on a bi-daily (or whatever) basis, where they don't have to trawl through 500 "Iz got me toaster to vibrate across me kitchen and anyone who says dat's not propellantless thrust can kiss my as*! and I'm LEAVING if u says dat!" posts because of the forum rules for the entire site's forum.
Eagleworks? Or NASA proper? -
#2244 by RERT on 26 Jan, 2016 09:27
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RE WolfofWallStreet comments on buoyancy in TT's tests: TT has stated (almost as an aside) that his measurement was an average up/down figure. That can only really mean that he has seen opposite forces in opposite orientations, at least one of which can't be buoyancy. Also, he has said he is seeing an immediate response and the RF pulse lasts one second, so for sure the frustrum isn't getting particularly hot on 63 Watts.
[That said, I think he very much needs to back up his statements with more data and details. He is talking about results much better than almost everyone, on a barely complete frustrum measured on a quickly assembled test rig. Like anyone with any sense I really want this effect to be true, but my credulity antennae are tingling a little over this report...]
R. -
#2245 by Notsosureofit on 26 Jan, 2016 14:21
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#2246 by SeeShells on 26 Jan, 2016 14:38
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RE WolfofWallStreet comments on buoyancy in TT's tests: TT has stated (almost as an aside) that his measurement was an average up/down figure. That can only really mean that he has seen opposite forces in opposite orientations, at least one of which can't be buoyancy. Also, he has said he is seeing an immediate response and the RF pulse lasts one second, so for sure the frustrum isn't getting particularly hot on 63 Watts.
[That said, I think he very much needs to back up his statements with more data and details. He is talking about results much better than almost everyone, on a barely complete frustrum measured on a quickly assembled test rig. Like anyone with any sense I really want this effect to be true, but my credulity antennae are tingling a little over this report...]
R.
I'm building to seek the truth, and so is EagleWorks, Tajmar or RFPlumber and even TT, and a host of others, the truth and data will prevail regardless of personal beliefs. The burden of proof is on our shoulders the builders not on believers or disbelievers or those on the fence. And Mother Nature will not let us bend her designs to our will regardless of beliefs or egos. Let him carry the burden of proof to a data level of little doubt, the pressure will grow for him to back up claims with a better designed test. Just like it has with me over these last few months and I'm taking the challenge.
This group is some of the sharpest minds I've worked with and we will certainly separate the wheat from the chaff to see what Mother Nature truly says.
Shell
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#2247 by sghill on 26 Jan, 2016 14:55
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This thread is about the EM Drive progress. It is being used by several NASA folk (they aren't using the social media sites, per their request for me to keep what is a fringe subject alive on this site) ahead of the big tests that are coming at its next NASA center very soon. They are using this site's threads on this because of the history of the subject's progress, the crowdsourcing efforts and the quick catch up they can do on a bi-daily (or whatever) basis, where they don't have to trawl through 500 "Iz got me toaster to vibrate across me kitchen and anyone who says dat's not propellantless thrust can kiss my as*! and I'm LEAVING if u says dat!" posts because of the forum rules for the entire site's forum.
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I think I did not miss this big news. Let's see
I'd like to hope that this hint from Chris means that EW has finally generated thrust signatures high enough that they can move to Glenn for the next round of testing. At lease that was the plan we'd heard about earlier from PM. -
#2248 by rfmwguy on 26 Jan, 2016 16:35
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There are enough rumors that it is safe to assume the project can move to the next stage. There isn't enough evidence that ew has the funding to do this. My guess is that if it were at grc's chamber, that test alone could take a major chunk out of ew's annual budget. All the environmental test labs I dealt with back in the day were $5K min. Can you imagine firing up the huge vacuum chamber at sandusky? Let's hope dr white and company can get the resources needed. We all need some real news...
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#2249 by VAXHeadroom on 26 Jan, 2016 16:47
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There are enough rumors that it is safe to assume the project can move to the next stage. There isn't enough evidence that ew has the funding to do this. My guess is that if it were at grc's chamber, that test alone could take a major chunk out of ew's annual budget. All the environmental test labs I dealt with back in the day were $5K min. Can you imagine firing up the huge vacuum chamber at sandusky? Let's hope dr white and company can get the resources needed. We all need some real news...
A thermal vacuum chamber at Goddard space flight center is about $15K/day. We rent time over there frequently... So yeah, that's a pricey test...
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#2250 by TheUberOverLord on 26 Jan, 2016 16:51
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Would it not be worthwhile if funds squash EW EM Drive testing in a vacuum to then at least do more testing using the same EM Drive in a normal atmosphere to compare results/differences?
At the moment it would seem that EW is the only one capable of doing this since they have already had one pass at a vacuum test.
Might produce some very rough baseline differences using the same EM Drive?
With the brain trust that EW seems to have. I can't figure out why all testing would need to halt simply because of the "Holy Grail" vacuum test not being able to get funding. I do understand the end-goal. But there are a few ways to get there without giving up because one way can't be funded for more EM Drive vacuum testing.
More normal atmosphere testing using the same EM Drive. Might even help justify funding more EW vacuum testing. Based on the results of course.
Don -
#2251 by wallofwolfstreet on 26 Jan, 2016 16:58
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RE WolfofWallStreet comments on buoyancy in TT's tests: TT has stated (almost as an aside) that his measurement was an average up/down figure. That can only really mean that he has seen opposite forces in opposite orientations, at least one of which can't be buoyancy. Also, he has said he is seeing an immediate response and the RF pulse lasts one second, so for sure the frustrum isn't getting particularly hot on 63 Watts.
[That said, I think he very much needs to back up his statements with more data and details. He is talking about results much better than almost everyone, on a barely complete frustrum measured on a quickly assembled test rig. Like anyone with any sense I really want this effect to be true, but my credulity antennae are tingling a little over this report...]
R.
True, I just saw that. TT states:QuoteMeasured thrust from my 1st EmDrive experiment was 2.2mN (0.22g) @ 63Wf or 35mN/kW, averaged from small end up & down test setups.
If he actually means that in the orientation where the small end was facing up he read 2.3 mN per say, and then when he reversed orientation so that the small end was facing down he read -2.1 mN, and so the "average" thrust was calculated at 2.2 mN, I would be quite impressed. That would go along way to diminishing the possibility of any thermal effects as being the source of the reading.
When you say they are 1 second pulses, does that mean that during the 1 second interval in which the RF pulse is applied, the thrust rises from zero to the measured value and back again to zero as the interval ends, so that thrust and applied RF pulse are coincident in time? That would be something.
EDIT: Just for fun and to help get a conceptual handle on just how much 2.2 mN is, I weighed some household objects on a scale I have that is accurate down to 0.01 mg (0.1 uN).
A standard, yellow 3M post-it-note (see attached figure) weighs almost exactly 4.4 mN. So measured force at the moment is almost exactly half a post-it-note.
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#2252 by Rodal on 26 Jan, 2016 18:34
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EXACT SOLUTION OF TheTRAVELLER'S TEST GEOMETRY
We use an exact solution of Maxwell's equations for standing-wave resonance of a truncated cone, I obtained using Wolfram Mathematica. The solution uses spherical Bessel functions and associated Legendre functions (as per Wolfram Mathematica definitions) and it also uses an intrinsic system of embedded spherical coordinates for the frustum of a cone. The solution is similar to Greg Egan's solution (http://gregegan.customer.netspace.net.au/SCIENCE/Cavity/Cavity.html) except in its generality: the solution of Maxwell's equations obtained using Wolfram Mathematica can calculate mode shapes for arbitrarily large quantum numbers m,n,p (while Egan's as presented was restricted to low order). I have compared my solution (using Mathematica) to the examples shown by Egan, and the comparison is excellent.
TheTraveller's frustum of a cone dimensions
The following data from TheTraveller, https://www.reddit.com/r/EmDrive/comments/40l1za/have_had_my_1st_build_design_data_confirmed/cz15iar, is used since it exactly matches the calculated Force/Power, and it features mode shape TE013 that user TheTraveller previously stated was recommended to him by Shawyer.Quote from: (edited and structured) from original posts by TheTravellerReturns
Geometry of the frustum of a cone resonant cavity:
BigDiameter: 0.259 m = 10.20 in
SmallDiameter: 0.159 m = 6.26 in
Length : 0.288 m = 11.34 in
Shape of end plates = Flat
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Predicted Eigenvalues of Resonance:
Predicted mode shape = TE013
Predicted natural frequency = 2.4053 GHz
(Rodal: both the eigenfrequency and eigenmode probably predicted using TheTraveller's spreadsheet modeling the conical frustum as the summation of a large number of cylindrical cavities with different diameters)
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Predicted quality of resonance and predicted force/power
Predicted Q (unloaded)= 86,200 (Rodal: not clear as to how TheTraveller calculated a Q, what approximate formula he used, but this predicted Q is definitely in the theoretical range for TE013, and these dimensions for copper)
Predicted Force/Power= 389 mN/kW (Rodal: probably predicted using Shawyer's formula, based on the above Q, the geometry, air as an internal medium and the predicted natural frequency and mode shape)
Therefore, this is the input geometry (in SI units:meters):
bigDiameter = 0.259;
smallDiameter = 0.159;
axialLength = 0.288;
from which one can calculate:
tanHalfAngleCone = (bigDiameter - smallDiameter)/(2*axialLength);
halfAngleConeRadians = ArcTan[tanHalfAngleCone];
halfAngleConeDegrees = (180/Pi)*halfAngleConeRadians;
r2 = Mean[{axialLength /(1 - ( smallDiameter /bigDiameter)), bigDiameter/(2*Sin[halfAngleConeRadians])}];
r1 = Mean[{axialLength /(( bigDiameter/ smallDiameter) - 1), smallDiameter/(2*Sin[halfAngleConeRadians])}];
Notice that, since the exact solution assumes spherical ends, while TheTraveller's truncated cone has flat ends, the spherical radii r1 and r2 are calculated as the mean value of the radii to a) the intersection of the ends with the lateral conical walls and b) the top of the dome. From analysis of the problem and verification using numerical analysis (comparison with COMSOL FEA solutions for a large number of examples) I have found out that this mean value is an excellent approximation to the solution of Maxwell's equations for a truncated cone with flat ends.
These input parameters result in the following values (in SI units) for the spherical radii and the cone half angle:
r1 = 0.461345 m
r2 = 0.751499 m
halfAngleConeDegrees = 9.84901 degrees
(notice that TheTraveller's cone is much closer to a cylinder than NASA's cone, which has a half cone angle of 14.8125 degrees. We suspect that the reason that TheTraveller chose this geometry, closer to a cylinder, was to meticulously obey Shawyer's prescription mandating for the small diameter base to exceed the dimensions for the cut-off frequency for a fictional open waveguide with the same diameter as the small base )
COMPARISON OF EXACT FREQUENCY with TheTraveller, for mode shape TE013
measured frequency: TheTraveller has not yet provided a measured natural frequency for his test
calculated natural frequency
(exact solution, Dr. Rodal using Wolfram Mathematica): 2.38793 GHz
calculated natural frequency
(by TheTraveller, using spreadsheet approximating cone as summation of cylinders): 2.4053 GHz
difference: (2.4053 - 2.38793)/2.4053 = 0.69 %
The exact solution is very close to the frequency calculated by TheTraveller approximating the cone as the sum of a large number of cylinders of constant cross-section, because the half cone angle of his frustum, being less than 10 degrees is pretty close to the geometry of a cylinder.
This difference of 0.69% in frequency is negligible, considering the fact that the TheTraveller's cone is presently "held by gravity" and is bound to have larger geometrical defects, which will affect the experimental natural frequency.
For reference, we also give the natural frequencies of the first four TE01p modes for TheTraveller's geometry:
TE011 = 1.77026*10^9 Hz
TE012 = 2.07472*10^9 Hz
TE013 = 2.38793*10^9 Hz
TE014 = 2.75007*10^9 Hz
COMPARISON OF QUALITY OF RESONANCE Q with TheTraveller, for mode shape TE013
TheTraveller does not specify what specific copper alloy he is using, so I will use, for reference, the same copper alloy used by NASA Eagleworks:
Material: 101 Copper Alloy properties (SI units):
mu = 0.999991*4*Pi*10^(-7);
resistivity = 1.71*10^(-8);
calculated quality of resonance
(exact solution, Dr. Rodal using Wolfram Mathematica): 86,552
calculated quality of resonance
(by TheTraveller, using spreadsheet approximating cone as summation of cylinders): 86,200
difference: (86,552 - 86,200)/86,200 = 0.41 %
(The difference in calculated Q is insignificant, given the fact that imperfections in geometry, surface and material will be responsible for much smaller values of experimental Q)
calculated skin depth (exact solution, Dr. Rodal using Wolfram Mathematica: 1.34682 micrometers
MAGNETIC VECTOR FIELD, for TheTraveller's experiment, mode shape TE013
I attach an image of the Magnetic Vector Field on a plane parallel to the longitudinal axis for TheTraveller's experiment.
Notice that the optimal place to locate the exciting loop would have been along the longitudinal axis, closer to the small diameter base of the frustum, and if the loop was preferred to be located on the conical wall, it would have been better located near the small base, at about ~22.5% +/-2.5% of the distance measured along the lateral conical wall from the small end to the large end of the frustum. (The magnetic vector field image below shows the length of the magnetic vectors proportional to their intensity and one can therefore see that the intensity of the magnetic field is much larger near the small base than at the middle of the frustum.)
TheTraveller, instead reported that the <<Coaxial-fed current loop antenna approximately located at the middle of the conical side wall of the frustum>>
Today, TheTravellerReturns responds to questions about the exciting loop from IslandPlaya, as follows:Quote from: https://www.reddit.com/r/EmDrive/comments/42n4w9/feko_movie_frequency_sweep_of_thetravellers/?sort=newThe 1/2 loop diameter, orientation and position is Secret Squirrel Secret Sauce stuff at this point in time. It will probably change when I get a stable 100W Rf output that will enable me to get some good tuning data at full power, where it is important and the money shot.
Initial loop diameter was derived from the equation I have posted but here it is again:
https://drive.google.com/file/d/0B7kgKijo-p0iQnUtV3JQRzhYNWc/view?usp=sharing
Can tell you that no part of the SMA connector is inside the frustum. The end of the SMA is in line with the side wall, very much like the linked image.
More like this image but not this coupler design:
https://drive.google.com/file/d/0B7kgKijo-p0idkFLYWQ5Y3l4dWc/view?usp=sharing
But that is enough Secret Squirrel Secret Sauce info for today.
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HEATING OF THE FRUSTUM WALLS
Observe that heating of the copper frustum walls occurs by induction heating, as a result of the eddy-currents induced on the walls by the magnetic field paralell to the walls, hence one can readily see that the eddy-currents are strongest on a ring around the cone, near the small base of the frustum, and that the eddy-currents and hence the heating of the small end plate will look like an outer ring on the small base (but not touching the circumference of the small base). There is also a ring of eddy-current, and hence heating, on the large base of the frustum.
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POYNTING VECTOR FIELD
For reference we also attach an image for the Poynting vector field on a plane parallel to the longitudinal axis for TheTraveller's experiment.
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#2253 by zen-in on 26 Jan, 2016 18:36
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True, I just saw that. TT states:QuoteMeasured thrust from my 1st EmDrive experiment was 2.2mN (0.22g) @ 63Wf or 35mN/kW, averaged from small end up & down test setups.
If he actually means that in the orientation where the small end was facing up he read 2.3 mN per say, and then when he reversed orientation so that the small end was facing down he read -2.1 mN, and so the "average" thrust was calculated at 2.2 mN, I would be quite impressed. That would go along way to diminishing the possibility of any thermal effects as being the source of the reading.
When you say they are 1 second pulses, does that mean that during the 1 second interval in which the RF pulse is applied, the thrust rises from zero to the measured value and back again to zero as the interval ends, so that thrust and applied RF pulse are coincident in time? That would be something.
There doesn't appear to be enough detail to answer any of your questions. First tests often yield results that turn out to be outlyers. One problem with using a strain guage scale is the movement of the test article is constrained by the miniscule deflection of the strain guage. A balance scale would offer more freedom of movement but there are problems with using one. With the strain guage scale it isn't possible to graph the step response. Any force appears as a square pulse. The sampling delay of the scale and very limited movement of the strain guage make it impossible to see the shape of the response. With a different measuring scheme strain guages can yield very accurate results with high fidelity. Most scales with a weight capacity of 1.5 kg have a resolution of just a gram. His must have better resolution but it is still pushing its capabilities. Since the output response will be masked by the limitations of the scale there is no way of inferring what caused the force. The step response will always be a square pulse. That's my guess anyway. -
#2254 by rfmwguy on 26 Jan, 2016 18:43
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New article today in the UK re emdrive:
http://www.telegraph.co.uk/sponsored/technology/technology-trends/12122176/nasa-warp-drive.html -
#2255 by Bob Woods on 26 Jan, 2016 19:49
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New article today in the UK re emdrive:
http://www.telegraph.co.uk/sponsored/technology/technology-trends/12122176/nasa-warp-drive.html
Nothing new, but maybe the TV story on the BBC is getting closer to air so some press is being generated. -
#2256 by A_M_Swallow on 26 Jan, 2016 21:18
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Usability of the EM Drive.
"20mN is 50% of what Roger predicts the frustum can do (at 100W inside the frustum)."
So 128 EM Drives could provide the ISS with over the 100 m/s it can need for yearly station keeping.
To get 100W into the frustum about 200W of electricity is needed.
128 * 200W = 25,600W (more if running on batteries when ISS is in shadow)
That is an extra solar panel.
Where n = number of thrusters = 128
m = mass of ISS = abut 420,000kg
F = ma
v = u + at
Δv = v - u
t = (Δv * m) / (F * n) = (100m/s * 420,000kg) / (0.02N * 128) = 16,406,250 seconds
Or 189.9 days -
#2257 by TheUberOverLord on 26 Jan, 2016 22:18
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Usability of the EM Drive.
"20mN is 50% of what Roger predicts the frustum can do (at 100W inside the frustum)."
So 128 EM Drives could provide the ISS with over the 100 m/s it can need for yearly station keeping.
To get 100W into the frustum about 200W of electricity is needed.
128 * 200W = 25,600W (more if running on batteries when ISS is in shadow)
That is an extra solar panel.
Where n = number of thrusters = 128
m = mass of ISS = abut 420,000kg
F = ma
v = u + at
Δv = v - u
t = (Δv * m) / (F * n) = (100m/s * 420,000kg) / (0.02N * 128) = 16,406,250 seconds
Or 189.9 days
Assuming that the EM Drive does what has been said it can do?
Don't you think that most likely nobody really knows ("Yet") what tweaks could/can be used to get better thrust results?
I'm not sold yet that anyone has reached maximum thrust potential with any EM Drive build yet and that as time progresses. It's possible and even probable ("Assuming the concept is real") that current thrust levels achieved. Could be many magnitudes lower than in the future, with tweaks. Call it wishful thinking, but currently I think it's in the realm of possibilities.
Don -
#2258 by A_M_Swallow on 26 Jan, 2016 22:50
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Assuming that the EM Drive does what has been said it can do?
Don't you think that most likely nobody really knows ("Yet") what tweaks could/can be used to get better thrust results?
I'm not sold yet that anyone has reached maximum thrust potential with any EM Drive build yet and that as time progresses. It's possible and even probable ("Assuming the concept is real") that current thrust levels achieved. Could be many magnitudes lower than in the future, with tweaks. Call it wishful thinking, but currently I think it's in the realm of possibilities.
Don
I just did the calculations on what can be reasonably expected this year. EM Drives are nearly at TRL 4 and may reach TRL 5/6 by the end of the year.
There are lots of possible improvements. The current ones are built to use the same radio frequency as micro wave ovens. Other frequencies will permit high thrust levels or to be physically smaller. -
#2259 by Rodal on 26 Jan, 2016 23:05
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Usability of the EM Drive.
"20mN is 50% of what Roger predicts the frustum can do (at 100W inside the frustum)."
So 128 EM Drives could provide the ISS with over the 100 m/s it can need for yearly station keeping.
To get 100W into the frustum about 200W of electricity is needed.
128 * 200W = 25,600W (more if running on batteries when ISS is in shadow)
That is an extra solar panel.
Where n = number of thrusters = 128
m = mass of ISS = abut 420,000kg
F = ma
v = u + at
Δv = v - u
t = (Δv * m) / (F * n) = (100m/s * 420,000kg) / (0.02N * 128) = 16,406,250 seconds
Or 189.9 days
Assuming that the EM Drive does what has been said it can do?
Don't you think that most likely nobody really knows ("Yet") what tweaks could/can be used to get better thrust results?
I'm not sold yet that anyone has reached maximum thrust potential with any EM Drive build yet and that as time progresses. It's possible and even probable ("Assuming the concept is real") that current thrust levels achieved. Could be many magnitudes lower than in the future, with tweaks. Call it wishful thinking, but currently I think it's in the realm of possibilities.
Don
I just did the calculations on what can be reasonably expected this year. EM Drives are nearly at TRL 4 and may reach TRL 5/6 by the end of the year.
There are lots of possible improvements. The current ones are built to use the same radio frequency as micro wave ovens. Other frequencies will permit high thrust levels or to be physically smaller.
1) In this post ( https://forum.nasaspaceflight.com/index.php?topic=39214.msg1474347#msg1474347 ), I formally prove that, according to all 3 theories (Shawyer's, McCulloch's and Notsosureofit's), the larger the EM Drive the more efficient it will be (the more force for a given amount of power). Hence, rather than use 128 EM Drives of the size used by DoItYourself and present experimenters on a small budget, it would make much more sense to make the EM Drive as large as physically possible (similarly it is much more efficient to have fewer large turbojet engines for aircraft than a lot of small turbojet engines, or large propellers for a ship than hundreds of small propellers). The reasons for this are:
a) the larger the EM Drive (everything else remaining the same), the larger the Q, because the larger the Volume/SurfaceArea ratio, the less energy is lost on the metal walls
b) the larger the EM Drive the more power one can input into it without running into electric breakdown of the air, multipaction in vacuum, etc.
2) Regardless of the tests, and theories, (if the EM Drive "anomalous force" ends up being something that can be efficiently used for space propulsion), and regardless of the much smaller experimental values measured in vacuum by NASA and by TU Dresden than in air, nobody has yet resolved the energy puzzle: the fact that (as brilliantly shown by Frobnicat and DeltaMass) if the EM Drive can produce constant acceleration for constant power (*),it is a free-energy machine, and that doesn't make sense. All tests have been run for an insignificant amount of time (seconds) so this important issue has not yet been dealt with theoretically or experimentally.
In other words, as shown by Frobnicat, if the EM Drive works as proposed by several proponents, and you can really get force proportional to power (*), then eventually one does NOT need any solar power, as free-energy can be produced by a couple of rotating EM Drives.
(*) with force/power > 1/c (added post-facto)