Roger also mentioned it is best to give the internal frustum surfaces a nice bright shiny polish. No need for Silver or Gold overcoats.
Quote from: Rodal on 05/28/2015 07:11 pmQuote from: kml on 05/28/2015 07:10 pm...Would TE011 actually work? 2.37GHz is below the TE01 cutoff frequency of 2.9GHz for a cylindrical waveguide of the small end (125cm). TE011 is actually not cut-off according to the exact solution with spherical ends for those dimensions listed above (125.7mm). It looks good and strong, very clear signal in the exact solution.It would have higher attenuation at the small end, which according to Todd's theory -which has my seal of approval - is a plus.I suppose that those that think that attenuation is bad may opt against, but it would be nice to test.The only advantage I see with TE013 is that it has the Poynting vector concentrated at the small end, and a local high amplitude at the small end.Hey Todd (WarpTech), we need to get your theory written up and in the Wiki http://emdrive.echothis.com/Theory
Quote from: kml on 05/28/2015 07:10 pm...Would TE011 actually work? 2.37GHz is below the TE01 cutoff frequency of 2.9GHz for a cylindrical waveguide of the small end (125cm). TE011 is actually not cut-off according to the exact solution with spherical ends for those dimensions listed above (125.7mm). It looks good and strong, very clear signal in the exact solution.It would have higher attenuation at the small end, which according to Todd's theory -which has my seal of approval - is a plus.I suppose that those that think that attenuation is bad may opt against, but it would be nice to test.The only advantage I see with TE013 is that it has the Poynting vector concentrated at the small end, and a local high amplitude at the small end.
...Would TE011 actually work? 2.37GHz is below the TE01 cutoff frequency of 2.9GHz for a cylindrical waveguide of the small end (125cm).
Quote from: TheTraveller on 05/28/2015 09:32 pmQuote from: aero on 05/28/2015 09:15 pmQuoteEDIT: Oh, by the way, the Poynting vector frequency is always twice the frequency of the electromagnetic field, its period is 1/2 the period of the electromagnetic field. It reverses direction twice as often as the electromagnetic fields.So the Poynting vector is an even number of cycles no matter the number of half-cycles of the drive frequency. Well, next we ask, is the drive frequency (period, wavelength) always an interger number of half-cycles? Seems it must be in order to resonate but the shape of the cavity and the existance of the dielectric makes one wonder, what is the effective drive frequency as far as the Poynting vector is concerned and does it remain always an even number of cycles everywhere within the cavity? Perhaps a more salient question would be, what is the strength of the Poynting vector force over one-half cycle as that should be the maximum Poynting force attainable, and how does it compare to F = 2PQ/c?Only the Experimental EM Drive used an internal small end dielectric. As a result, it had low Q and low thrust.The Demonstrator and Flight Thruster EM Drives are high Q and high thrust devices which did not use a dielectric.Shawyer says using a dielecrtic:1) increases loss,2) reduces Q,3) reduces thrust.His reported results back up that claimSo why the interest in dielectrics?Why not? Would you be satisfies if I wrote, "and the existance or not of the dielectric"?
Quote from: aero on 05/28/2015 09:15 pmQuoteEDIT: Oh, by the way, the Poynting vector frequency is always twice the frequency of the electromagnetic field, its period is 1/2 the period of the electromagnetic field. It reverses direction twice as often as the electromagnetic fields.So the Poynting vector is an even number of cycles no matter the number of half-cycles of the drive frequency. Well, next we ask, is the drive frequency (period, wavelength) always an interger number of half-cycles? Seems it must be in order to resonate but the shape of the cavity and the existance of the dielectric makes one wonder, what is the effective drive frequency as far as the Poynting vector is concerned and does it remain always an even number of cycles everywhere within the cavity? Perhaps a more salient question would be, what is the strength of the Poynting vector force over one-half cycle as that should be the maximum Poynting force attainable, and how does it compare to F = 2PQ/c?Only the Experimental EM Drive used an internal small end dielectric. As a result, it had low Q and low thrust.The Demonstrator and Flight Thruster EM Drives are high Q and high thrust devices which did not use a dielectric.Shawyer says using a dielecrtic:1) increases loss,2) reduces Q,3) reduces thrust.His reported results back up that claimSo why the interest in dielectrics?
QuoteEDIT: Oh, by the way, the Poynting vector frequency is always twice the frequency of the electromagnetic field, its period is 1/2 the period of the electromagnetic field. It reverses direction twice as often as the electromagnetic fields.So the Poynting vector is an even number of cycles no matter the number of half-cycles of the drive frequency. Well, next we ask, is the drive frequency (period, wavelength) always an interger number of half-cycles? Seems it must be in order to resonate but the shape of the cavity and the existance of the dielectric makes one wonder, what is the effective drive frequency as far as the Poynting vector is concerned and does it remain always an even number of cycles everywhere within the cavity? Perhaps a more salient question would be, what is the strength of the Poynting vector force over one-half cycle as that should be the maximum Poynting force attainable, and how does it compare to F = 2PQ/c?
EDIT: Oh, by the way, the Poynting vector frequency is always twice the frequency of the electromagnetic field, its period is 1/2 the period of the electromagnetic field. It reverses direction twice as often as the electromagnetic fields.
Quote from: StrongGR on 05/28/2015 12:06 pmThis was a thought occurring me a moment ago. I have just shown that inside these cavities there is a tiny gravitational effect. Per se this effect is too small account for the observed thrust, if confirmed. But, is there any change in the light propagation inside such cavities causing an asymmetry due to these small gravitational effects?Yes.Change gravity-> change a fundamental of space-> change time.Personally Im still stuck in the "energy density" conundrum. If we think of space as a support mechanism acting in such a manner as to be a "carrier" of energy, and we alter an aspect of space then the energy being carried must also be impacted in some form. In stronger gravity fields spectral lines change as atoms are more compressed and molecules move more rapidly, Refraction would change. Extreme examples would be black holes. QUESTION: What would you expect to happen to a light beam originating in normal space (the lab) traversing through a modified area of space (inside the cavity) and exiting the modified area back into normal space. Freuency shift? polarization shift?... or nothing because its back in normal space and we cant measure/detect a changeShining a laser through a small hole in the base and top of a cavity "might" display transverse spectral changes?. Or have 2 holes in the base and a small internal mirror attached to the cavity top...It "might" be interesting to have a straight line of small holes directly down each side of a cavity allowing a laser to traverse directly through the cavity. Shifting the laser sequentially from bottom to top may reveal a difference in cavity internal events (or not)?.
This was a thought occurring me a moment ago. I have just shown that inside these cavities there is a tiny gravitational effect. Per se this effect is too small account for the observed thrust, if confirmed. But, is there any change in the light propagation inside such cavities causing an asymmetry due to these small gravitational effects?
Quote from: TheTraveller on 05/29/2015 12:16 am...A 100W 3.85GHz Rf amp will dent the budget by $4,000 if I go with MiniCircuit unit. Have started searching ham resources for a lower cost unit. Suggestions on other 100W 3.5-4.0GHz amps most welcome.Suggestion: start by exciting TE011 at 2.4 GHz which should be cheaper and more effective than TE013. Look at @Notsosureofit's equation http://emdrive.echothis.com/@notsosureofit_Hypothesis (more sophisticated approach than Shawyer's)Mode: TE011Frequency: 2.37833 GHz
...A 100W 3.85GHz Rf amp will dent the budget by $4,000 if I go with MiniCircuit unit. Have started searching ham resources for a lower cost unit. Suggestions on other 100W 3.5-4.0GHz amps most welcome.
Quote from: TheTraveller on 05/28/2015 04:43 pmFlight Thruster build update:From the best photo of the Flight Thruster I could find and allowing for 2mm thick walls, to add thermal mass and reduce the rate of thermal expansion, the following internal Flight Thruster dimensions were obtained:Length: 138.6mmSmall diameter: 125.7mmBig diameter: 231.4mmApplying those to my spreadsheet generated:Df: 0.638Frequency: 3.85GHzMode: TE013I then asked Roger Shawyer did I get close? His reply:Df: 0.635Frequency: 3.9003GHzMode: TE013I'm VERY happy with that as my Rf gen can easily go to that frequency. Time now to finalise drawings and get some copper sheet laser cut.Roger also mentioned it is best to give the internal frustum surfaces a nice bright shinny polish. No need for Silver or Gold overcoats.Will the end-plates be removable in your design? Can you do an experiment, attaching some Ferrite blocks or Metglass to the inside surface of the "big" end?
Flight Thruster build update:From the best photo of the Flight Thruster I could find and allowing for 2mm thick walls, to add thermal mass and reduce the rate of thermal expansion, the following internal Flight Thruster dimensions were obtained:Length: 138.6mmSmall diameter: 125.7mmBig diameter: 231.4mmApplying those to my spreadsheet generated:Df: 0.638Frequency: 3.85GHzMode: TE013I then asked Roger Shawyer did I get close? His reply:Df: 0.635Frequency: 3.9003GHzMode: TE013I'm VERY happy with that as my Rf gen can easily go to that frequency. Time now to finalise drawings and get some copper sheet laser cut.Roger also mentioned it is best to give the internal frustum surfaces a nice bright shinny polish. No need for Silver or Gold overcoats.
Quote from: TheTraveller on 05/29/2015 01:02 amQuote from: Rodal on 05/29/2015 12:21 amQuote from: TheTraveller on 05/29/2015 12:16 am...A 100W 3.85GHz Rf amp will dent the budget by $4,000 if I go with MiniCircuit unit. Have started searching ham resources for a lower cost unit. Suggestions on other 100W 3.5-4.0GHz amps most welcome.Suggestion: start by exciting TE011 at 2.4 GHz which should be cheaper and more effective than TE013. Look at @Notsosureofit's equation http://emdrive.echothis.com/@notsosureofit_Hypothesis (more sophisticated approach than Shawyer's)Mode: TE011Frequency: 2.37833 GHzReplicate 1stExperiment 2nd.Yea I know dull and boring but in my experience, when doing something very new and new to me, replication wins out at the end of the day.It is your $4,000 U$D. I hope you get all the data necessary to attain a replication (Is it possible to replicate?. Wasn't the Flight Thruster a device made in collaboration with Boeing ? )
Quote from: Rodal on 05/29/2015 12:21 amQuote from: TheTraveller on 05/29/2015 12:16 am...A 100W 3.85GHz Rf amp will dent the budget by $4,000 if I go with MiniCircuit unit. Have started searching ham resources for a lower cost unit. Suggestions on other 100W 3.5-4.0GHz amps most welcome.Suggestion: start by exciting TE011 at 2.4 GHz which should be cheaper and more effective than TE013. Look at @Notsosureofit's equation http://emdrive.echothis.com/@notsosureofit_Hypothesis (more sophisticated approach than Shawyer's)Mode: TE011Frequency: 2.37833 GHzReplicate 1stExperiment 2nd.Yea I know dull and boring but in my experience, when doing something very new and new to me, replication wins out at the end of the day.
...As I've said, the frustum mimics gravity over a narrow bandwidth, very well. This effect is many orders of magnitude larger than the effect predicted in Marco's paper. I think it will overwhelm any experimental evidence of the latter. Todd
Quote from: WarpTech on 05/29/2015 12:27 am...As I've said, the frustum mimics gravity over a narrow bandwidth, very well. This effect is many orders of magnitude larger than the effect predicted in Marco's paper. I think it will overwhelm any experimental evidence of the latter. ToddIf you look at the images I posted for the Poynting vector field distribution ( http://forum.nasaspaceflight.com/index.php?topic=37642.msg1381389#msg1381389 ) for the geometry of the Flight Thruster that TheTraveller is going to use (look at the Poynting component images in the LONGITUDINAL direction only), mode TE013 has more of a fine gradient than TE02, which has a finer gradient than TE011. The higher the longitudinal quantum number "p", the finer the graduation, with the Poynting vector being weakest at the big end and strongest at the small end.The pictures show the Poynting vector for the first half period. It reverses direction during the second period.Perhaps we do want to have this gradual variation in Poynting vector strength from one end to the other, and that's the advantage of TE013. Unfortunately this is not showing the attenuation, but it is interesting to see the gradient in longitudinal direction component of the Poynting vector switching direction from cell to cell...
Therefore if we used a laser shining through an active cavity, could we "view" the distortion effect and hence have a visual analog gauge that tracks the fluctuating intensity of the "distortion" happening inside?... a "warping-effect-gauge"
Yes its shorter than cutoff, which is good as it wont be impacted by the microwaves themselves, but its traversing a modified G field (or at least a mimic of it). Whats your thoughts on the possibility for interferometry to detect wavelength or temporal related changes of the laser?.
...Since copper has a very low K and diamagnetic permeability, and the frustum is copper on all sides, the Thrust is practically designed to be nil. ...I'm just saying, that there are ways to overcome the limitations by using non-linear materials inside. Just a thought...Todd
Quote from: arc on 05/29/2015 04:20 amYes its shorter than cutoff, which is good as it wont be impacted by the microwaves themselves, but its traversing a modified G field (or at least a mimic of it). Whats your thoughts on the possibility for interferometry to detect wavelength or temporal related changes of the laser?.That's my point. It only mimics gravity over a limited bandwidth "near the cut-off wavelength". The laser's wavelength is many orders of magnitude smaller, so it doesn't see any G field. It just sees a microwave background. The "relative" temporal effects happen only to the frequencies of the waves near the cut-off wavelength of the cavity. The laser's frequency is unaffected by this. Interferometry is the wrong tool for this application, IMO.
Quote from: Paul Novy on 05/28/2015 07:49 amI'm just gonna leave this here..."Macroscopic and Direct Light Propulsion of Bulk Graphene Material"http://arxiv.org/ftp/arxiv/papers/1505/1505.04254.pdfQuoteThe force generated from such a process/mechanism is muchlarger than the force generated directly from the conventional light pressure, which ismuch smaller than the force required to propel the samples. QuoteThe mechanism behind this novel phenomenon is believed to be anefficient light-induced ejected electron emission process, following an Auger-like pathdue to both the unique band structure of graphene and its macroscopic morphology ofthis unique material. This article is showing that for certain types of materials, light can impart more force to the material, than it would if it were simply used to as a photon rocket to push the same material. The difference is the Auger Effect, where the incoming light causes a population inversion in the material, that then causes electrons to be ejected from the material, greatly increasing the force by many orders of magnitude. Perhaps a similar effect can be obtained asymmetrically in a cavity?Thank you for posting it!Todd
I'm just gonna leave this here..."Macroscopic and Direct Light Propulsion of Bulk Graphene Material"http://arxiv.org/ftp/arxiv/papers/1505/1505.04254.pdfQuoteThe force generated from such a process/mechanism is muchlarger than the force generated directly from the conventional light pressure, which ismuch smaller than the force required to propel the samples. QuoteThe mechanism behind this novel phenomenon is believed to be anefficient light-induced ejected electron emission process, following an Auger-like pathdue to both the unique band structure of graphene and its macroscopic morphology ofthis unique material.
The force generated from such a process/mechanism is muchlarger than the force generated directly from the conventional light pressure, which ismuch smaller than the force required to propel the samples.
The mechanism behind this novel phenomenon is believed to be anefficient light-induced ejected electron emission process, following an Auger-like pathdue to both the unique band structure of graphene and its macroscopic morphology ofthis unique material.
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)