Quote from: Rodal on 05/08/2015 02:37 amQuote from: Bubs on 05/08/2015 02:23 amCan someone explain why the EMdrive experiment isn't run inside Helmholtz Coils (to cancel Earth magnetic field)?The propulsion could be easily explained by the interaction between the large DC currents used to operate the magnetron/RF power amplifier with Earth’s magnetic field by way of the Lorentz force. In other words, a homopolar motor. This is an experiment that any child can do with a battery and a piece of wire:http://en.wikipedia.org/wiki/Homopolar_motorTo do a proper measurement, the Earth's magnetic field should be canceled around the experiment using this setup:http://en.wikipedia.org/wiki/Helmholtz_coilAssuming one believes Shawyer's experimental reports, wouldn't that interaction with the Earth's negative field be negated by the fact that Shawyer claims to have measured similar thrust/PowerInput for the EM Drive pointing small base UP (vertical), small base DOWN (vertical), small base to the RIGHT (horizontal) ?I referring to NASA's experimental setup, not Shawyer's. (I consider Shawyer's setup to be too sloppy - rotating platform, with laptop? with fans? and rotating hard-disk? Extremely unprofessional).In NASA's setup, there is still a shared ground connection between the source and the device-under-test, so it's not fully balanced AC. You can never be sure about residual ground currents, ground loops etc. It can easily cause this residual force, and explain the large variation between various experimental setups.It would be a wise precaution to run this experiment inside Helmholtz coils to cancel possible interactions with Earth's magnetic field.
Quote from: Bubs on 05/08/2015 02:23 amCan someone explain why the EMdrive experiment isn't run inside Helmholtz Coils (to cancel Earth magnetic field)?The propulsion could be easily explained by the interaction between the large DC currents used to operate the magnetron/RF power amplifier with Earth’s magnetic field by way of the Lorentz force. In other words, a homopolar motor. This is an experiment that any child can do with a battery and a piece of wire:http://en.wikipedia.org/wiki/Homopolar_motorTo do a proper measurement, the Earth's magnetic field should be canceled around the experiment using this setup:http://en.wikipedia.org/wiki/Helmholtz_coilAssuming one believes Shawyer's experimental reports, wouldn't that interaction with the Earth's negative field be negated by the fact that Shawyer claims to have measured similar thrust/PowerInput for the EM Drive pointing small base UP (vertical), small base DOWN (vertical), small base to the RIGHT (horizontal) ?
Can someone explain why the EMdrive experiment isn't run inside Helmholtz Coils (to cancel Earth magnetic field)?The propulsion could be easily explained by the interaction between the large DC currents used to operate the magnetron/RF power amplifier with Earth’s magnetic field by way of the Lorentz force. In other words, a homopolar motor. This is an experiment that any child can do with a battery and a piece of wire:http://en.wikipedia.org/wiki/Homopolar_motorTo do a proper measurement, the Earth's magnetic field should be canceled around the experiment using this setup:http://en.wikipedia.org/wiki/Helmholtz_coil
Quote from: BubsExtremely unprofessional ?
Extremely unprofessional
Quote from: ThereIWas3 on 05/07/2015 10:47 pmUsing low temps and low power is definitely the way to go during this "how does it work?" phase. Much safer. But keep your eyes away from it and have a microwave leak detector at hand.The high-power engineering can be done after the basic principles involved are understood.2.45GHz is home microwave oven frequency. Most run around 600W. I'm sure forum menber have seen what 600W of microwave can do in regard to plasma creation and other pryotechinque tricks in a microwave oven.Using a 1kW magnetron could do serious damage to people & equipment around a EM Drive if any microwave energy escaped. So please use microwave leak detectors and limit time close to the cavity.Shawyer has experienced this. He made this comment about leaking microwaves interfering with his video camera when filming the rotary test rig.Is why I'll build a Faraday Cage around my test unit so to stop microwave leaks interfering with my test and control system.
Using low temps and low power is definitely the way to go during this "how does it work?" phase. Much safer. But keep your eyes away from it and have a microwave leak detector at hand.The high-power engineering can be done after the basic principles involved are understood.
Quote from: Bubs on 05/08/2015 02:35 amThere is still a shared ground connection between the source and the device-under-test, so it's not fully balanced AC. You can never be sure about residual ground currents, ground loops etc. It can easily cause this residual force, and explain the large variation between various experimental setups.It would be a wise precaution to run this experiment inside Helmholtz coils to cancel possible interactions with Earth's magnetic field.I ran the numbers and was surprised how little current it takes. I assumed it ran in the shield of the RF feed coax and took length to be 0.5m. That yields 4 Amps of ground loop current necessary to produce 100 uN in the Earth's field.So yeah - except that reversing the test article pretty much reverses the thrust and does NOT reverse your Lorentz force. So I think it's unnecessary.
There is still a shared ground connection between the source and the device-under-test, so it's not fully balanced AC. You can never be sure about residual ground currents, ground loops etc. It can easily cause this residual force, and explain the large variation between various experimental setups.It would be a wise precaution to run this experiment inside Helmholtz coils to cancel possible interactions with Earth's magnetic field.
No and no. That 10 Amps is main current, not residual ground loop current . Reversing the test article leaves the coax feed exiting in the same place, so also no.
Quote from: Rodal on 04/30/2015 03:38 amLatest paper by Dr. White, on http://ntrs.nasa.gov/ , exploring the idea of the quantum vacuum not being an absolute immutable and nondegradable state, and examining some rami cations of the quantum vacuum being able to support non-trivial spatial variations in density. They claim that their "considerations showed no predictions that were contrary to observation, and in fact duplicated predictions for energy states associated with the primary quantum number."http://hdl.handle.net/2060/20150006842Dynamics of the Vacuum and Casimir Analogs to the Hydrogen AtomHarold White, Jerry Vera,y Paul Bailey,z Paul March,x Tim Lawrence,{ Andre Sylvester, and David BradyNASA Johnson Space Center2101 NASA Parkway, Houston, TX 77058(Dated: April 2, 2015)Publication Date: Apr 02, 2015Document ID: 20150006842 (Acquired Apr 28, 2015)Subject Category: PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; ATOMIC AND MOLECULAR PHYSICS; NUMERICAL ANALYSIS; COMPUTER PROGRAMMING AND SOFTWAREReport/Patent Number: JSC-CN-33080Document Type: Technical ReportFinancial Sponsor: NASA Johnson Space Center; Houston, TX, United StatesOrganization Source: NASA Johnson Space Center; Houston, TX, United StatesDescription: 9p; In EnglishThere is an error in the integration of equation 11. Apparently their "simple enough" integration was not simple enough!
Latest paper by Dr. White, on http://ntrs.nasa.gov/ , exploring the idea of the quantum vacuum not being an absolute immutable and nondegradable state, and examining some rami cations of the quantum vacuum being able to support non-trivial spatial variations in density. They claim that their "considerations showed no predictions that were contrary to observation, and in fact duplicated predictions for energy states associated with the primary quantum number."http://hdl.handle.net/2060/20150006842Dynamics of the Vacuum and Casimir Analogs to the Hydrogen AtomHarold White, Jerry Vera,y Paul Bailey,z Paul March,x Tim Lawrence,{ Andre Sylvester, and David BradyNASA Johnson Space Center2101 NASA Parkway, Houston, TX 77058(Dated: April 2, 2015)Publication Date: Apr 02, 2015Document ID: 20150006842 (Acquired Apr 28, 2015)Subject Category: PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; ATOMIC AND MOLECULAR PHYSICS; NUMERICAL ANALYSIS; COMPUTER PROGRAMMING AND SOFTWAREReport/Patent Number: JSC-CN-33080Document Type: Technical ReportFinancial Sponsor: NASA Johnson Space Center; Houston, TX, United StatesOrganization Source: NASA Johnson Space Center; Houston, TX, United StatesDescription: 9p; In English
Quote Rodal:Interestingly (for this thread's discussion due to the significance that the NASA experimenters have placed on the dielectric being responsible for providing the measured thrust) is what happens in the High Density PolyEthylene (HDPE) dielectric polymer insert. Because the dimensions of the dielectric are not negligible compared to the EM Drive's dimension, and the dielectric is not modeled as just a boundary condition.The loss tangent of HDPE is reported to betan delta = 0.0004Therefore the intrinsic impedance angle isintrinsic impedance angle =(ArcTan[0.0004])/2Therefore, inside the HDPE dielectric the electric and magnetic fields, instead of being out of phase by 90 degrees (as they are in the air or vacuum medium), will be out of phase by:90 - (ArcTan[0.0004])/2 = 89.9998 degreesThis phase angle (89.9998 degrees) will show practically no visual difference with 90 degrees at the resolution of the following image :Mr Rodal can you advise me on the value .0004 in your work above, is that in degrees or radians or just a figure that one simply takes the arctan of. Im trying to use the "bc" program in linux command line to get a grip on the overall topic, and bc reports results in radians, hence the requirement to do a 180/pi conversion. echo "scale=20; 90 - (a(0.0004)/2)*(180/(4*a(1)))" | bc -l89.98854084470853845905Thanksarc
Rodal:Interestingly (for this thread's discussion due to the significance that the NASA experimenters have placed on the dielectric being responsible for providing the measured thrust) is what happens in the High Density PolyEthylene (HDPE) dielectric polymer insert. Because the dimensions of the dielectric are not negligible compared to the EM Drive's dimension, and the dielectric is not modeled as just a boundary condition.The loss tangent of HDPE is reported to betan delta = 0.0004Therefore the intrinsic impedance angle isintrinsic impedance angle =(ArcTan[0.0004])/2Therefore, inside the HDPE dielectric the electric and magnetic fields, instead of being out of phase by 90 degrees (as they are in the air or vacuum medium), will be out of phase by:90 - (ArcTan[0.0004])/2 = 89.9998 degreesThis phase angle (89.9998 degrees) will show practically no visual difference with 90 degrees at the resolution of the following image :
Im seeing an overlap between this kind of work and work done by T.T.Brown...anyone care to briefly comment on it?(Incase your unfamiliar with T.T. Brown, he discovered Biefeld-Brown effect, but also discovered another force that he insisted was NOT biefeld-brown effect (ion wind), also he believed the dielectric played a primary role in the force, and that a reaction force existed on "all solid material bodies making up the physical environment")He makes some very peculiar statements in his 1929 article, which lead me to believe he was an honest experimenter (ofcourse he explains in terms of what people knew in the 1920's)the 1929 article & gravitator patent: http://www.rexresearch.com/gravitor/gravitor.htm#patentThis patent strikes me the most (attached): US3187206 (1965), He has a Half-Wave Radiator, tapered dielectric member etc... please tell me what you think because im seeing a fair bit of crossover.I seriously think there is something to be gleaned from TTBrown's work.Regards.PS: Im thoroughly enjoying the thread, wish i was as up to speed as you lot.
Quote from: FieldEffect on 05/08/2015 08:19 amIm seeing an overlap between this kind of work and work done by T.T.Brown...anyone care to briefly comment on it?(Incase your unfamiliar with T.T. Brown, he discovered Biefeld-Brown effect, but also discovered another force that he insisted was NOT biefeld-brown effect (ion wind), also he believed the dielectric played a primary role in the force, and that a reaction force existed on "all solid material bodies making up the physical environment")He makes some very peculiar statements in his 1929 article, which lead me to believe he was an honest experimenter (ofcourse he explains in terms of what people knew in the 1920's)the 1929 article & gravitator patent: http://www.rexresearch.com/gravitor/gravitor.htm#patentThis patent strikes me the most (attached): US3187206 (1965), He has a Half-Wave Radiator, tapered dielectric member etc... please tell me what you think because im seeing a fair bit of crossover.I seriously think there is something to be gleaned from TTBrown's work.Regards.PS: Im thoroughly enjoying the thread, wish i was as up to speed as you lot. Asymmetrical Capacitors for Propulsion : http://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/20040171929.pdfConclusions: "... In spite of decades of speculation about possible new physical principles being responsible for the thrust produced by ACTs and lifters, we find no evidence to support such a conclusion. On the contrary, we find that their operation is fully explained by a very simple theory that uses onlyelectrostatic forces and the transfer of momentum by multiple collisions. ".My understanding is that for emDrive, the new tests were successfully performed in a (close to) vacuum.
Consider the following EM Drive design:1st component: A symmetrical resonator cavity that is optimized to store energy at high Q, and plays no role in thrust. Here, we want to store the lowest order mode that the waveguide can sustain because it has the slowest wave velocity inside the waveguide. By targeting the slowest wave velocity, we are maximizing the amount of stored electromagnetic momentum for a given amount electromagnetic energy.p = E/v, where v << c inside the waveguide.E = P*t, energy is power in x time (assuming a lossless cavity)2nd component: We need a frustum that matches the diameter of the resonant chamber "at the small end" and slowly expands to a TBD length and diameter. As the waveguide expands, the wavelength will be increasing proportional to the increasing wave velocity. We want it to expand to near it's free space value.3rd component: We need a partial reflector, between the two, so that we can have resonance in one chamber, and thrust in the other. Like a laser.Principle of operation:When the energy stored in the resonant chamber is released into the frustum, it expands due to the increased wave velocity to a longer wavelength before it is reflected. It leaves the "nozzle" with momentum p1, but when it arrives at the reflector, it has momentum p2 << p1, because the wave velocity has increased "significantly".The reflected waves then travel back into the frustum only to find that due to their increased wavelength, now they don't fit anymore, so they are attenuated. Again, absorbing the momentum into the frustum as heat and kinetic energy in the "forward" direction. ....
....To put it quantum mechanically:N photons are injected at momentum p1 = N*h/lambda_1N photons are reflected at the far end with momentum p2 = N*h/lambda_2The wavelengths are not equal. Momentum is conserved because the system moves forward. The red-shifted photons are mimicking a gravitational field. They are trying to escape a gravity well, only to be reflected back in and fall back through the event horizon as wave velocity goes to zero. (Sorry I love that analogy!)Todd Desiato
Such a shame it's so difficult to simply put it in space and check. It would have saved Woodward 20 years and I don't know how many years on this already.I speak as someone who watched Apollo 11 on the moon.
Quote from: WarpTech on 05/08/2015 05:51 amConsider the following EM Drive design:1st component: A symmetrical resonator cavity that is optimized to store energy at high Q, and plays no role in thrust. Here, we want to store the lowest order mode that the waveguide can sustain because it has the slowest wave velocity inside the waveguide. By targeting the slowest wave velocity, we are maximizing the amount of stored electromagnetic momentum for a given amount electromagnetic energy.p = E/v, where v << c inside the waveguide.E = P*t, energy is power in x time (assuming a lossless cavity)2nd component: We need a frustum that matches the diameter of the resonant chamber "at the small end" and slowly expands to a TBD length and diameter. As the waveguide expands, the wavelength will be increasing proportional to the increasing wave velocity. We want it to expand to near it's free space value.3rd component: We need a partial reflector, between the two, so that we can have resonance in one chamber, and thrust in the other. Like a laser.Principle of operation:When the energy stored in the resonant chamber is released into the frustum, it expands due to the increased wave velocity to a longer wavelength before it is reflected. It leaves the "nozzle" with momentum p1, but when it arrives at the reflector, it has momentum p2 << p1, because the wave velocity has increased "significantly".The reflected waves then travel back into the frustum only to find that due to their increased wavelength, now they don't fit anymore, so they are attenuated. Again, absorbing the momentum into the frustum as heat and kinetic energy in the "forward" direction. To put it quantum mechanically:N photons are injected at momentum p1 = N*h/lambda_1N photons are reflected at the far end with momentum p2 = N*h/lambda_2The wavelengths are not equal. Momentum is conserved because the system moves forward. The red-shifted photons are mimicking a gravitational field. They are trying to escape a gravity well, only to be reflected back in and fall back through the event horizon as wave velocity goes to zero. (Sorry I love that analogy!)Todd DesiatoExcellent. This makes to me much more engineering/scientific sense than the closed cavity design pioneered by Shawyer and imitated in the US and Chinese laboratories.So it looks to me that either the UK/US/Chinese measurements are an artifact, or if they are real (*), the design you sketched above should produce more thrust than the present designs.___(*) if they are real, I would like to summarize the present understanding regarding the energy paradox. I thought you had reached a common conclusion but @frobnicat raised apparently new points that apparently still need to be addressed ?
Consider the following EM Drive design:1st component: A symmetrical resonator cavity that is optimized to store energy at high Q, and plays no role in thrust. Here, we want to store the lowest order mode that the waveguide can sustain because it has the slowest wave velocity inside the waveguide. By targeting the slowest wave velocity, we are maximizing the amount of stored electromagnetic momentum for a given amount electromagnetic energy.p = E/v, where v << c inside the waveguide.E = P*t, energy is power in x time (assuming a lossless cavity)2nd component: We need a frustum that matches the diameter of the resonant chamber "at the small end" and slowly expands to a TBD length and diameter. As the waveguide expands, the wavelength will be increasing proportional to the increasing wave velocity. We want it to expand to near it's free space value.3rd component: We need a partial reflector, between the two, so that we can have resonance in one chamber, and thrust in the other. Like a laser.Principle of operation:When the energy stored in the resonant chamber is released into the frustum, it expands due to the increased wave velocity to a longer wavelength before it is reflected. It leaves the "nozzle" with momentum p1, but when it arrives at the reflector, it has momentum p2 << p1, because the wave velocity has increased "significantly".The reflected waves then travel back into the frustum only to find that due to their increased wavelength, now they don't fit anymore, so they are attenuated. Again, absorbing the momentum into the frustum as heat and kinetic energy in the "forward" direction. To put it quantum mechanically:N photons are injected at momentum p1 = N*h/lambda_1N photons are reflected at the far end with momentum p2 = N*h/lambda_2The wavelengths are not equal. Momentum is conserved because the system moves forward. The red-shifted photons are mimicking a gravitational field. They are trying to escape a gravity well, only to be reflected back in and fall back through the event horizon as wave velocity goes to zero. (Sorry I love that analogy!)Todd Desiato