Could an explanation for the EmDrive's internal workings be paralleled to something like cavitation bubbles in liquid? Such as: It's kind of a wild thought, but for some reason it made sense to me.
Quote from: kdhilliard on 07/07/2015 07:20 pmQuote from: TheTraveller on 07/07/2015 12:18 pmRoger Shawyer's IAC 2014 paper has been peer reviewed and accepted for publication in Acta Astronautica, the IAF journal.2014 Peer Review IAC 14 paper C4,8.5 final.pdfI started making a page by page comparison between this newly uploaded paper and the earlier IAC 14 paper C4,8.5 final.pdf to determine what changes were introduced in the review process, but it turns out that the two pdf files are byte-identical.Traveller, can you please confirm that you uploaded the correct paper, and that there were, in fact, no changes introduced into the paper during the review process.~KirkRoger Shawyer told me his IAC 2014 paper was accepted for publication. He did not mention any changes. Will ask him and report back.
Quote from: TheTraveller on 07/07/2015 12:18 pmRoger Shawyer's IAC 2014 paper has been peer reviewed and accepted for publication in Acta Astronautica, the IAF journal.2014 Peer Review IAC 14 paper C4,8.5 final.pdfI started making a page by page comparison between this newly uploaded paper and the earlier IAC 14 paper C4,8.5 final.pdf to determine what changes were introduced in the review process, but it turns out that the two pdf files are byte-identical.Traveller, can you please confirm that you uploaded the correct paper, and that there were, in fact, no changes introduced into the paper during the review process.~Kirk
Roger Shawyer's IAC 2014 paper has been peer reviewed and accepted for publication in Acta Astronautica, the IAF journal.2014 Peer Review IAC 14 paper C4,8.5 final.pdf
Duty cycle on magnetrons...a new power supply would be needed AND figure on 50% reduced RF power (CW) output, or about 400W from an 800W magnetron. Realistically, most of us will have to stick with off the shelf stuff. I suggest that independent experimenters who want to go in that direction should do so, but be aware of the costs associated with custom power supplies and tubes. Here's what I suggest to those about to embark on a more expensive experiment (unless your wealthy ):1) prove you've gotten some results (video the build and test - avoid vaporware/unsubstantiated claims)2) publicly commit to open source disclosure (unless I am mistaken, this forum is non-commercial)3) describe where you want to take it next in detail (maybe ask for equip donations)4) set up a gofundme or similar site and link to it (with the mods permission, that is)We have a unique opportunity to shove this thing along or simply prove its not possible. While I'd love to prove its real, I'd also feel accomplishment by showing the alternative, as we all should.As a side note, if I see the slightest positive results when I fire this thing up (prior to the live video stream) I plan to get a 3rd party in to film it as well. Could be a local media outlet or my old colleague who works at NASA Glenn nearby. drbagelbites could get his school's CCTV station there, shell could twist an arm or two in her local media.Look, this thing could be revolutionary, but if not properly announced, demonstrated and verified, its just another free energy, perpetual motion machine in the public's eye. Experimenters need to think carefully how its presented and it should be done so in a professional manner. /end soapbox ramble.
Quote from: deuteragenie on 07/07/2015 08:20 pmI will repeat my questions here, as it seems they disapeared in the flood of other issues:Quote from: Rodal on 07/07/2015 02:11 pm* There is a net, non-zero Poynting vector over an integer number of periods. This negates what Greg Egan showed, where he concluded that the Poynting vector is zero for an EM Drive. Has this been demonstrated/accurately calculated? It has been shown that some slices of the data, when represented graphically appear to have large non-zeo Poynting vector. I guess noone will object to this. This does not mean that a) all slices (... infinitesimally small) exhibit the same behavior and b) that the many small (again, infinitesimally small) Poynting vectors which may or may not be graphically represented do not cancel out the large ones which dwarf them graphically. Or am I missing something ?Quote from: Rodal on 07/07/2015 02:11 pm* The Poynting vector is increasing with time. This is required in more general situations (for radiation pressure all that is required is a non-zero average). This is very significant. It remains to be explored whether it is just a transient.Roughly the same comment on this, but added to the potential need to consider much longer and finer time steps. Has this been taken into account?1) Your wording and statements are different than mine. I stand 100% behind what I stated. I don't agree with your wording. Now I have one comment from WallofWolfStreet that it was intuitively obvious that the Poynting vector would not sum up to zero over an integer number of periods. Your question negates the fact that it may be "intutively obvious" as you are asking the question. However in retrospect I have to agree with WallofWolfStreet that with the RF feed on is not surprising that the Poynting vector average is not zero.2) What is not intuitively obvious is that the Poynting vector increases with time. I have gone out of my way to state the obvious, that I only looked at 2 cycles and that it may be a transient. I think that I stated that every single time3) Aside from wording. You have access to the same numerical data that I do. They are in the csv files. You and others can calculate the Poynting vector field as well from the data.
I will repeat my questions here, as it seems they disapeared in the flood of other issues:Quote from: Rodal on 07/07/2015 02:11 pm* There is a net, non-zero Poynting vector over an integer number of periods. This negates what Greg Egan showed, where he concluded that the Poynting vector is zero for an EM Drive. Has this been demonstrated/accurately calculated? It has been shown that some slices of the data, when represented graphically appear to have large non-zeo Poynting vector. I guess noone will object to this. This does not mean that a) all slices (... infinitesimally small) exhibit the same behavior and b) that the many small (again, infinitesimally small) Poynting vectors which may or may not be graphically represented do not cancel out the large ones which dwarf them graphically. Or am I missing something ?Quote from: Rodal on 07/07/2015 02:11 pm* The Poynting vector is increasing with time. This is required in more general situations (for radiation pressure all that is required is a non-zero average). This is very significant. It remains to be explored whether it is just a transient.Roughly the same comment on this, but added to the potential need to consider much longer and finer time steps. Has this been taken into account?
* There is a net, non-zero Poynting vector over an integer number of periods. This negates what Greg Egan showed, where he concluded that the Poynting vector is zero for an EM Drive.
* The Poynting vector is increasing with time. This is required in more general situations (for radiation pressure all that is required is a non-zero average). This is very significant. It remains to be explored whether it is just a transient.
There is nothing more deceptive than an obvious fact.
I love rumors! Facts can be so misleading, where rumors, true or false, are often revealing.
Quote from: SeeShells on 07/07/2015 02:21 pmQuote from: CW on 07/07/2015 07:23 am.......I also tried to point out many a post ago in (I think) the last EM drive thread, that a standing wave might be interpretable as an 'exotic' type of dynamically created massive particle. This whole tapered frustum actually looks to me as if this geometry squeezed one side of this dynamically created exotic particle equivalent. Assuming this point of view, this squeezed dynamic particle should then react and try to escape the squeezing towards the wider end of the frustum, hence being sort of accelerated, while the equivalent but opposite impulse is being imparted towards the smaller frustum end. If this were the case, the type of squeezing reaction might even depend on the type of exotic particle equivalent that is being dynamically generated in terms of frequency, energy density and field distribution/modes. Just the same as static types of particles have different properties that particle physics knows.Yes, yes yes! Perfect. What wonderfully weird actions within 1/3 of a wavelength are occurring by the antenna? A action the can impart spin and momentum and mass to that virtual particle that is being created within the small endcap? It is a evanescent wave action generating first order forces! Evanescent waves can move MIE particles, gold spheres and even charge your cell phone! This isn't a small force we're imparting to the virtual massive particles, this is an evanescent wave action can move particles (MIE spheres with billions of atoms). The poynting vectors which give the momentum and spin of the massive virtual a direction to "push" and that's to the large end.They head out to the large (*edit) end imparting force but being virtual particles that cannot exist without a corresponding real field from the small end cap they decay and disappear back into the Quantum vacuum. This action doesn't violate anything by making a virtual massive particle at the antenna adding energy and direction and thrust towards the large cavity end and then decaying back into the Quantum Vacuum.I read somewhere and it went like this... short-lived high-mass force-carrier particles seem to violate the laws of conservation of energy and mass -- their mass just can't come out of nowhere!" They can and they do, they are a result of the Heisenberg Uncertainty principle. These high-mass particles come into being and seem to escape the standard model's notice somehow. These massive virtual particles don't violate COE, in the end of the small cavity within 1/3 wavelength. Assisted by the evanescent waves they come into existence, The poynting vectors give them direction and upon decaying their kinetic energy plus their mass is imparted to the Frustum giving it acceleration and thrust.......Oh my! This explanation really works for me! I think this really explains the importance of the standing waves forming and collapsing. I was impressed with the sinusoidal behaviour of the waves we saw in the animations of meep data. More specifically this is an excellent outline of how an EM drive would work as a closed system!!
Quote from: CW on 07/07/2015 07:23 am.......I also tried to point out many a post ago in (I think) the last EM drive thread, that a standing wave might be interpretable as an 'exotic' type of dynamically created massive particle. This whole tapered frustum actually looks to me as if this geometry squeezed one side of this dynamically created exotic particle equivalent. Assuming this point of view, this squeezed dynamic particle should then react and try to escape the squeezing towards the wider end of the frustum, hence being sort of accelerated, while the equivalent but opposite impulse is being imparted towards the smaller frustum end. If this were the case, the type of squeezing reaction might even depend on the type of exotic particle equivalent that is being dynamically generated in terms of frequency, energy density and field distribution/modes. Just the same as static types of particles have different properties that particle physics knows.Yes, yes yes! Perfect. What wonderfully weird actions within 1/3 of a wavelength are occurring by the antenna? A action the can impart spin and momentum and mass to that virtual particle that is being created within the small endcap? It is a evanescent wave action generating first order forces! Evanescent waves can move MIE particles, gold spheres and even charge your cell phone! This isn't a small force we're imparting to the virtual massive particles, this is an evanescent wave action can move particles (MIE spheres with billions of atoms). The poynting vectors which give the momentum and spin of the massive virtual a direction to "push" and that's to the large end.They head out to the large (*edit) end imparting force but being virtual particles that cannot exist without a corresponding real field from the small end cap they decay and disappear back into the Quantum vacuum. This action doesn't violate anything by making a virtual massive particle at the antenna adding energy and direction and thrust towards the large cavity end and then decaying back into the Quantum Vacuum.I read somewhere and it went like this... short-lived high-mass force-carrier particles seem to violate the laws of conservation of energy and mass -- their mass just can't come out of nowhere!" They can and they do, they are a result of the Heisenberg Uncertainty principle. These high-mass particles come into being and seem to escape the standard model's notice somehow. These massive virtual particles don't violate COE, in the end of the small cavity within 1/3 wavelength. Assisted by the evanescent waves they come into existence, The poynting vectors give them direction and upon decaying their kinetic energy plus their mass is imparted to the Frustum giving it acceleration and thrust.......
.......I also tried to point out many a post ago in (I think) the last EM drive thread, that a standing wave might be interpretable as an 'exotic' type of dynamically created massive particle. This whole tapered frustum actually looks to me as if this geometry squeezed one side of this dynamically created exotic particle equivalent. Assuming this point of view, this squeezed dynamic particle should then react and try to escape the squeezing towards the wider end of the frustum, hence being sort of accelerated, while the equivalent but opposite impulse is being imparted towards the smaller frustum end. If this were the case, the type of squeezing reaction might even depend on the type of exotic particle equivalent that is being dynamically generated in terms of frequency, energy density and field distribution/modes. Just the same as static types of particles have different properties that particle physics knows.
Quote from: aero on 07/07/2015 05:33 pm@Rodal-Meep can output the time slices as frequently as desired, up to once per time step, or 6527 h5 file time indices (data sets) per run. So instead 10 h5 data sets/cycle, there would result just over 200 h5 data sets/cycle. Neither I nor my computer can deal with that much data over a full run. It would be much smaller impact to increase the run time beyond 32 cycles. As for increasing the csv data frequency, better to install the latest Meep from source, then explore the use of the newer features of the software to reduce the data at run time, prior to output. That means we would need to drop back 5 and punt, for now, but later we might have a stronger meep to support our efforts.OK, I'm here trying to make sense of the units in your Meep output, in order to be able to interpret the time response.We start with the output:Quote My latest run has completed. This is the output at the final step.; run time set to 13.052188647619047 meep time This is printed output from control file set.;Meep progress: 13.054/13.052188647619047 = 100.0% done in 6479.3s, -0.9s to go;run 0 finished at t = 13.054 (6527 timesteps) and there is extra information, that I need you to double check as to whether you know it for a fact to be precise to make calculations:320 time slices in the whole run32 cycles in the whole run (hence 10 time slices per cycle)Scale Factor "a" = 0.3 metersThen we start by calculating the Meep unit of time:tMeep = a /c = 0.3 m / 299792458 m/s = 1.000692*10^(-9) secondsThen we calculate the period, the time taken for one cycle:Period = 13.054 tMeep / 32 = 4.082199*10^(-10) secondsFrequency = 1/Period = 2.44966 GHzThis is very close to 2.45 GHz so it seems fine. (Don't need Harminv to calculate frequency if this is correct).However, let's use the Finite Difference time step information:time per time slice =( 6527 time steps/ 320 time slices) (13.054 timeMeep/6527 time steps)*(0.3 m/299792458 m/s timeMeep) = = 4.082199*10^(-11) seconds/time slicewhich is consistent with the previously obtained result for Period time, if one multiplies it by 10 time slices per period.However, if you take a look at this picture, there are not 10 slices per period, but there are approximately 9 time slices per period:multiplying 4.082199*10^(-11) seconds/time slices * 9 time slices = 3.673979 * 10^(-10) secondswhich gives:2.7218 GHz frequency instead of 2.44966 GHzQUESTION:Where does the information come from that there there are exactly 10 time slices per cycle ?How do you know that?I can see that you may know that there are 320 time slices for the complete output. but how do you now that there are 10 time slices per cycle?
@Rodal-Meep can output the time slices as frequently as desired, up to once per time step, or 6527 h5 file time indices (data sets) per run. So instead 10 h5 data sets/cycle, there would result just over 200 h5 data sets/cycle. Neither I nor my computer can deal with that much data over a full run. It would be much smaller impact to increase the run time beyond 32 cycles. As for increasing the csv data frequency, better to install the latest Meep from source, then explore the use of the newer features of the software to reduce the data at run time, prior to output. That means we would need to drop back 5 and punt, for now, but later we might have a stronger meep to support our efforts.
My latest run has completed. This is the output at the final step.; run time set to 13.052188647619047 meep time This is printed output from control file set.;Meep progress: 13.054/13.052188647619047 = 100.0% done in 6479.3s, -0.9s to go;run 0 finished at t = 13.054 (6527 timesteps)
...The extraordinary claims made in the 1st 3 pages, especially in Table 1 on page 1, which mean the mentioned EMDrives work as claimed and are now peer reviewed history. Accept them as factual and move on to new fields.As for your other physicists, I sure hope they have not dug themselves in so deep, they can't retract their views.
...My purpose in life is to apply critical and logical thinking. I have a track record of beating lawyers 110% of the time at that game
Quote from: demofsky on 07/07/2015 07:59 pmQuote from: SeeShells on 07/07/2015 02:21 pmQuote from: CW on 07/07/2015 07:23 am.............@CW has the right idea, squeezed light is trying to move to the big end where it is less squeezed, and pushes the frustum the other way in the process. The main issue I have with @SeeShell's idea is that, there is not enough energy in the cavity to create a significant amount of "massive" virtual particles. It would be difficult to even prove that a single electron-positron pair is being created at these energy levels, even at the surface of the antenna. What is in the QV is orders of magnitude too small to couple to, at these energies. IF it could work as Dr. White surmised, as a QV MHD thruster, the amount of current density and magnetic field strength required would be enormous. The QV energy density is concentrated above frequencies > 1022Hz. Frequency in the EM drive is many orders of magnitude below what the QV would need to couple to it.Todd
Quote from: SeeShells on 07/07/2015 02:21 pmQuote from: CW on 07/07/2015 07:23 am.............
Quote from: CW on 07/07/2015 07:23 am.............
.......
Don't forget this is the 2nd peer reviewed EMDrive paper, the 1st being the Chinese paper as attached. [* 2013 NWPU 2013.pdf]
the various statements made there confirming for the 2nd time in a peer reviewed paper (Chinese peer review was 1st) the EMdrive generates Force as claimed.
Quote from: deuteragenie on 07/07/2015 09:16 pm...No Sir, I did not draw conclusions hastingly,but after careful analysis. I have S.B., S.M. and Ph.D. degrees in Aero & Astro, specialize in the field of numerical analysis and 35 years of experience in R&D. I have carefully examined the problem, and have carefully chosen my words. Obviously the graphical data presented is only a small amount of what I have examined. I don't have any interest here in convincing you or anybody else of anything, on the contrary, I would prefer if others independently do their own independent calculations. I am interested in convincing myself of what is going on (and remain to this point unconvinced whether the EM Drive is a genuine propulsion device and if so how is this happening). Concerning your experience beating lawyers 110% of the time, I have been a successful Scientific Expert Witness in litigation, where the purpose is not to beat lawyers but to prove the case to Judge and Jury (at least in the USA and Canada, where I have been an Expert Witness).
...
All our dreams can come true, if we have the courage to pursue them.
...Quote from: Walt DisneyAll our dreams can come true, if we have the courage to pursue them.
One of the more piquant consequences of a self-contained (rotary) overunity energy system is that it makes interstellar travel a snap relative to our current options. Acceleration will increase with time at no fuel cost.Here are some ship times based on special relativity, when travelling to the nearest star (Alpha Centauri, 4.2 lightyears distant), at various constant accelerations, accelerating to halfway and then braking the other half of the way. 0.1 gee 12.5 years (0.57c max)1 gee 3.5 years (0.95c max)10 gee 8.9 months (>0.99c max)100 gee 1.4 months (>0.99c max)1,000 gee 7.3 days (>0.99c max)10,000 gee 18 hours (>0.99c max)
So I'll modify my magnetron (which can be done) get 100% duty and double the thrust? I'm not really jazzed about that as WarpTech (and I) think that the DC component from the magnetron assists in the thrust. I'll take this first step with a 50% acceleration component if that's what it is.
Quote from: SeeShells on 07/07/2015 07:32 pmSo I'll modify my magnetron (which can be done) get 100% duty and double the thrust? I'm not really jazzed about that as WarpTech (and I) think that the DC component from the magnetron assists in the thrust. I'll take this first step with a 50% acceleration component if that's what it is.No modification to the Magnetron is required (besides cooling). The real changes would be to the power supply. The 50% duty cycle comes from the way the power supply is constructed. It is a half-wave voltage doubler. The transformer takes 60hz 120v(ish) from the wall socket and steps it up to ~2500 volts AC. During the positive half of the AC wave the magnetron receives the voltage from the capacitor (~2500 volts) plus the voltage from the transformer. The other half of the 60hz cycle is negative and the magnetron gets nothing because the diode is diverting the negative voltage off to ground. Replace this kit with a constant voltage current limited 5,000v-ish DC supply and 100% duty cycle is yours for the taking. As a bonus you'll get the ability to somewhat modify the power output too.If you want an alternative path to more power, pull a waveguide off of your resonator and mount two identical magnetrons facing each other in it. They will slave (* more appropriately called injection locking) together like magic. You can stick more than two of them in the same waveguide, at anti-node intervals. Low budget linear accelerators do this to get more power into the box, though they usually will use a circulator instead of just a waveguide. Impedance match this waveguide to your resonator or the magnetrons closest to it will take severe abuse from the power leaking back from the resonator.For cooling I've wrapped my magnetron with flexible copper tubing for cooling and am using thermal switches so they don't cook. Used microwaves are cheap, but there is no sense in frying the magnetrons unnecessarily.
Quote from: ElizabethGreene on 07/07/2015 10:25 pmQuote from: SeeShells on 07/07/2015 07:32 pmSo I'll modify my magnetron (which can be done) get 100% duty and double the thrust? I'm not really jazzed about that as WarpTech (and I) think that the DC component from the magnetron assists in the thrust. I'll take this first step with a 50% acceleration component if that's what it is.No modification to the Magnetron is required (besides cooling). The real changes would be to the power supply. The 50% duty cycle comes from the way the power supply is constructed. It is a half-wave voltage doubler. The transformer takes 60hz 120v(ish) from the wall socket and steps it up to ~2500 volts AC. During the positive half of the AC wave the magnetron receives the voltage from the capacitor (~2500 volts) plus the voltage from the transformer. The other half of the 60hz cycle is negative and the magnetron gets nothing because the diode is diverting the negative voltage off to ground. Replace this kit with a constant voltage current limited 5,000v-ish DC supply and 100% duty cycle is yours for the taking. As a bonus you'll get the ability to somewhat modify the power output too.If you want an alternative path to more power, pull a waveguide off of your resonator and mount two identical magnetrons facing each other in it. They will slave (* more appropriately called injection locking) together like magic. You can stick more than two of them in the same waveguide, at anti-node intervals. Low budget linear accelerators do this to get more power into the box, though they usually will use a circulator instead of just a waveguide. Impedance match this waveguide to your resonator or the magnetrons closest to it will take severe abuse from the power leaking back from the resonator.For cooling I've wrapped my magnetron with flexible copper tubing for cooling and am using thermal switches so they don't cook. Used microwaves are cheap, but there is no sense in frying the magnetrons unnecessarily.Wow. Very nice. FWIW I have in my designs (for the future) the same 2 magnetrons slaved!I had no idea you were pursuing a build. If you would like to share, that would be great or not. Your call. shell