With all the past talks about quantum fields and general relativity as reference frames for explaining EMdrive thrust, I've stumbled on this:http://www.spacedaily.com/reports/How_spacetime_is_built_by_quantum_entanglement_999.htmlnot sure if it may bring something to the table...but it appears to be one of the first (theoretical) steps in developing a Theory of Everything. Cant find the technical papers right away, but those might contain something useful for the theorists inhere? (It's way above my head anyway)
Err...I don't know if this is a lightbulb moment or a senior moment, but if the cavity generates an asymmetrical pattern of eddy currents in the surface of the frustrum, wouldn't that interact with the Earth's magnetic field to produce a net force?
...I just re-read Greg Eagan's paper more thoroughly. He and Yang end with the same result, the integration of T*n over the surface. His "proof" is based on there being ONLY standing waves, of sin(wt) & cos(wt). He does not consider the Evanescent waves that are decaying into the confined volume of the small end, where c/K << c. These would have exponentially decaying terms, exp[-a*t - b*x], where "a" and "b" are variables dependent on the shape of the cavity, per Zeng and Fan. The part that determines thrust, based on the shape of the cavity, was neglected by Egan and Yang in their analyses. Their resulting closed form equation is correct, the D, E and B, H fields they plug into it are not. Optimize their integral force equation for the correct representation for D, E and B, H, i.e., NOT standing waves, including non-linear materials, then design a system to meet those requirements....
...The part that determines thrust, based on the shape of the cavity, was neglected by Egan and Yang in their analyses. Their resulting closed form equation is correct, the D, E and B, H fields they plug into it are not....
Quote from: Flyby on 05/29/2015 08:51 amWith all the past talks about quantum fields and general relativity as reference frames for explaining EMdrive thrust, I've stumbled on this:http://www.spacedaily.com/reports/How_spacetime_is_built_by_quantum_entanglement_999.htmlnot sure if it may bring something to the table...but it appears to be one of the first (theoretical) steps in developing a Theory of Everything. Cant find the technical papers right away, but those might contain something useful for the theorists inhere? (It's way above my head anyway)I think that this is what you're looking for:"Tomography from Entanglement"http://arxiv.org/pdf/1412.1879v1.pdfAlthough math and concepts depicted there are way outside my abilities but someone might find it useful.
...When you state: <<Optimize their integral force equation for the correct representation for D, E and B, H, i.e., NOT standing waves>> are you proposing to only consider the evanescent wave terms and to ignore the standing wave terms in the analysis? (since the standing wave terms perfectly cancel out when averaged over an integer number of time periods)Or do you see any interaction/coupling between the standing wave terms and the evanescent wave terms so that both have to be considered in the analysis?....
Quote from: WarpTech on 05/29/2015 02:59 am...The part that determines thrust, based on the shape of the cavity, was neglected by Egan and Yang in their analyses. Their resulting closed form equation is correct, the D, E and B, H fields they plug into it are not....If you are correct that Prof. Yang neglected the part that determines the thrust in her analysis, how is she then calculating a thrust force?Something is amiss. Greg Egan makes sense, because he concludes that there is no thrust.But how can we say that on one hand Prof. Yang neglects the part that determines thrust and on the other hand she calculates a thrust force? Where does her calculated thrust force come from then ?
Quote from: Rodal on 05/29/2015 12:37 pmQuote from: WarpTech on 05/29/2015 02:59 am...The part that determines thrust, based on the shape of the cavity, was neglected by Egan and Yang in their analyses. Their resulting closed form equation is correct, the D, E and B, H fields they plug into it are not....If you are correct that Prof. Yang neglected the part that determines the thrust in her analysis, how is she then calculating a thrust force?Something is amiss. Greg Egan makes sense, because he concludes that there is no thrust.But how can we say that on one hand Prof. Yang neglects the part that determines thrust and on the other hand she calculates a thrust force? Where does her calculated thrust force come from then ?I'm saying, in her analysis she neglects to "provide" information on what her functions for E, H are. We have no idea what she plugged into her FEA software. Egan on the other hand, doesn't even consider it and assumes all waves are sin(wt) & cos(wt), therefore there is no force. Yang doesn't say what the functions are she uses. If her amplitude for E and H include an exponential decaying factors that are asymmetrical, then they are not periodic and that's all she needs.Todd
...Dr. Yang's calculation of thrust is deeply flawed. Although the integration of Maxwell stress tensor on the thruster boundary is the way to proceed, if no EM radiation is allowed (no photon rocket) it is easy to prove that that integration amounts exactly to zero, since nothing is coming out from a surface at infinity and the total electromagnetic field momentum within the volume enclosed by those surfaces is zero, too. As a result no thrust at all....
Quote from: WarpTech on 05/29/2015 01:51 pmQuote from: Rodal on 05/29/2015 12:37 pmQuote from: WarpTech on 05/29/2015 02:59 am...The part that determines thrust, based on the shape of the cavity, was neglected by Egan and Yang in their analyses. Their resulting closed form equation is correct, the D, E and B, H fields they plug into it are not....If you are correct that Prof. Yang neglected the part that determines the thrust in her analysis, how is she then calculating a thrust force?Something is amiss. Greg Egan makes sense, because he concludes that there is no thrust.But how can we say that on one hand Prof. Yang neglects the part that determines thrust and on the other hand she calculates a thrust force? Where does her calculated thrust force come from then ?I'm saying, in her analysis she neglects to "provide" information on what her functions for E, H are. We have no idea what she plugged into her FEA software. Egan on the other hand, doesn't even consider it and assumes all waves are sin(wt) & cos(wt), therefore there is no force. Yang doesn't say what the functions are she uses. If her amplitude for E and H include an exponential decaying factors that are asymmetrical, then they are not periodic and that's all she needs.ToddDr. Yang's calculation of thrust is deeply flawed. Although the integration of Maxwell stress tensor over the thruster boundary is the way to proceed, if no EM radiation is allowed (no photon rocket) it is easy to prove that that integration amounts exactly to zero, since nothing is coming out from a surface at infinity and the total electromagnetic field momentum within the volume enclosed by those surfaces is zero, too. As a result no thrust at all.If, by the other hand, the non-zero thrust resulting from FEA calculation is due to a kind of directional EM radiation, the radiated ouptut power would be around 100 MW, way larger than the total input power, so that thrust result is very likely due to numerical errors.
Quote from: MyronQG on 05/29/2015 03:05 pm...Dr. Yang's calculation of thrust is deeply flawed. Although the integration of Maxwell stress tensor on the thruster boundary is the way to proceed, if no EM radiation is allowed (no photon rocket) it is easy to prove that that integration amounts exactly to zero, since nothing is coming out from a surface at infinity and the total electromagnetic field momentum within the volume enclosed by those surfaces is zero, too. As a result no thrust at all....No, this is where you are making an assumption. The EM field momentum within the volume is NOT zero. The symmetry with which it is attenuated and absorbed by the cavity, will determine the forces. It is not "de-facto" symmetrical on all surfaces.
Quote from: Rodal on 05/29/2015 12:29 pm...When you state: <<Optimize their integral force equation for the correct representation for D, E and B, H, i.e., NOT standing waves>> are you proposing to only consider the evanescent wave terms and to ignore the standing wave terms in the analysis? (since the standing wave terms perfectly cancel out when averaged over an integer number of time periods)Or do you see any interaction/coupling between the standing wave terms and the evanescent wave terms so that both have to be considered in the analysis?....The interaction is, as the standing waves dissipate heat in the copper, they lose energy and shift to longer wavelengths, where attenuation takes over from dissipation and imparts momentum to the copper, not heat. The standing waves provide the stored energy, but the evanescent waves do the work.
The interaction is, as the standing waves dissipate heat in the copper, they lose energy and shift to longer wavelengths, where attenuation takes over from dissipation and imparts momentum to the copper, not heat. The standing waves provide the stored energy, but the evanescent waves do the work.
...If we were going to design an experiment where we generate enough thrust that the results were obvious (i.e. thrust more than overcomes any thermal effects) I see NASA has proposed a 100kW magnetron firing into a 10" tall copper frustum. ...
Due to these predictions by Dr. White’s computer simulations NASA Eagleworks has started to build a 100 Watt to 1,200 Watt waveguide magnetron microwave power system that will drive an aluminum EM Drive shaped like a truncated cone.
Apologies, just reading my post had the solution to the item on a vacuum; question #2 should just read - is there any benefit to inducing a vacuum with a vacuum pump prior to a q thruster test? If the frustrum is air tight than by pulling a vacuum we can just disconnect the pump eliminating the problem of lost microwaves. So questions:#1 - Cooling jacket - worth trying to cool the q thruster?#2 - internal vacuum - worth trying to run it at a vacuum, say -5kPag#3 - Silver plated copper - better q factor than aluminum? No dielectric needed with magnetron due to harmonics?
Quote from: WarpTech on 05/29/2015 03:15 pmQuote from: MyronQG on 05/29/2015 03:05 pm...Dr. Yang's calculation of thrust is deeply flawed. Although the integration of Maxwell stress tensor on the thruster boundary is the way to proceed, if no EM radiation is allowed (no photon rocket) it is easy to prove that that integration amounts exactly to zero, since nothing is coming out from a surface at infinity and the total electromagnetic field momentum within the volume enclosed by those surfaces is zero, too. As a result no thrust at all....No, this is where you are making an assumption. The EM field momentum within the volume is NOT zero. The symmetry with which it is attenuated and absorbed by the cavity, will determine the forces. It is not "de-facto" symmetrical on all surfaces.I refer to the volume enclosed by the surface at infinity and the thruster's boundary (topologically equivalent to a hollow sphere).
AERO: When you considered evanescent waves in the Truncated Cone, modelled as a two-dimensional flat trapezium:1) Considering only evanescent waves inside the cavity, did MEEP calculate any net thrust force? If the answer is no, why not? (Did you consider any losses in your analyis? Did you input a tan delta value for the Dielectric polymer insert?)2) Was attenuation taking into account in the MEEP analysis? If yes, what were the attenuation parameters that you considered?