Quote from: TheTraveller on 05/14/2015 11:55 amHave modified my Shawyer Df calculator and best Df scanner as per the derived Shawyer Df equation, using cutoff wavelength and guide wavelength as per microwave industry supplied equations. I assume Shawyer did not supply these equations in his papers as they are equations that should be known to microwave industry individuals skilled in the art. Anyway they are now in the public record.The scanner still sweeps the frequency range 0Hz to 10GHz but reports the frequency that generates a Df as close to 1 as possible but not over.The attached results are very interesting as the frequency needed to get the Df to just below 1 is very close to the Rf driving frequency used to generate Lambda0 or free wavelength in the selected medium.While I'm still testing the spreadsheet, which meets both of Shawyers boundary conditions, the results for my Flight Thruster design are looking to be very close to what I could build. Bit of dimension tweaking should get the Df 1 frequency to the 3.85GHz Shawyer used.Will post the spreadsheet after a bit more testing.I've built and tested many microwave cavities over many years.You're guided wavelength equation is wrong, because this is for a rectangular wave guide (i.e., not even a rectangular cavity)You need to derive mode of frequency yourself (unless there is a paper somewhere) for a circular tapered cavity. There is no other way around it. I would start with Balanis - Advanced Engineering Electromagnetics as he derives a few examples for other topologies. Right now everything you are doing is wrong because you don't understand the physics. I would study that book from front to cover if I were you.Also, to the guy operating the microwave magnetron outside of the microwave: STOPAt best you are violating the laws of your local government's regulatory committee for the electromagnetic spectrum. At worst you will damage your body. At this frequency, the damage is somewhat insidious. Due to low water content of your skin, you don't feel the heat, but internal nerve endings can be damaged so that chronic phantom pain can appear. Sometimes days after exposure. Please STOP otherwise you will inevitably be reported to your government.
Have modified my Shawyer Df calculator and best Df scanner as per the derived Shawyer Df equation, using cutoff wavelength and guide wavelength as per microwave industry supplied equations. I assume Shawyer did not supply these equations in his papers as they are equations that should be known to microwave industry individuals skilled in the art. Anyway they are now in the public record.The scanner still sweeps the frequency range 0Hz to 10GHz but reports the frequency that generates a Df as close to 1 as possible but not over.The attached results are very interesting as the frequency needed to get the Df to just below 1 is very close to the Rf driving frequency used to generate Lambda0 or free wavelength in the selected medium.While I'm still testing the spreadsheet, which meets both of Shawyers boundary conditions, the results for my Flight Thruster design are looking to be very close to what I could build. Bit of dimension tweaking should get the Df 1 frequency to the 3.85GHz Shawyer used.Will post the spreadsheet after a bit more testing.
Yes. And the way to silence sceptics is to make measurements on a fully-boxed rig - including battery. All these trailing feeds generate pseudo-forces. That would be OK if thrust were Newton level - but it ain't, so it ain't.
Quote from: SeeShells on 05/15/2015 08:58 pmThe search function aren't that super here euuuuu. Why is the RF injected into the side of the EM Device. I know it's a basic question but can someone expand on it a little more? ShellsNo one else has chimed in, so I'll give this a shot. I believe the choice of antenna position is predominantly a function of the antenna beam pattern, and the desire to couple maximum energy into the cavity.A simple dipole antenna radiates/couples well in the perpendicular direction, so placing a dipole antenna perpendicular to the cavity wall would allow direct coupling into the dominant resonant direction (i.e. between the concave/convex end plates).(attached image from http://www.trevormarshall.com/byte_articles/byte1.htm)I had proposed (many pages back) that the use of a waveguide to inject a magnetron's signal had the effect of a directional beam pattern that was much better at injecting energy than removing energy from the cavity. (since resonanting energy is dominantly between the end plates, a waveguide input roughly perpendicular to the walls would inject energy better than remove energy) However, I'll readily admit my reasoning may be overly simplistic.Thanks,James
The search function aren't that super here euuuuu. Why is the RF injected into the side of the EM Device. I know it's a basic question but can someone expand on it a little more? Shells
Quote from: Rodal on 05/16/2015 12:57 amQuote from: StrongGR on 05/14/2015 06:00 pmI am back with an updated draft after some terrible news around about NASA dismissing these researches. They should not as, otherwise, it could happen as with Galilei having his detractors even not trying to look in the telescope, just dismissing on faith.I have analysed the case of the frustum and the results appear to be striking. One must admit that geometry comes to rescue not just general relativity. For this particular geometry the cavity can be made susceptible to gravitational effects if your choice of the two radii of the cavity is smart enough. This is something to be confirmed yet, just my theoretical result, but shocking anyway.As usual, any comment is very welcome.In page 8, equation 34 of http://forum.nasaspaceflight.com/index.php?action=dlattach;topic=36313.0;attach=830137, for the integral on dr', should the limits, instead of0 to ((r2-r1)/h) z' + r2ber1 to ((r2-r1)/h) z' + r1 ?Good Point ! But volume integral ? 0 to ... ((r2-r1)/h) z' + r1 /l0 ? (seems circular that way)It's Eq. 18 that still bothers me a bit. Invoking the Heaviside step function is OK, but I don't see the addl. components being detectable outside the cavity w/o a non-linear term. Maybe I'm missing something ?
Quote from: StrongGR on 05/14/2015 06:00 pmI am back with an updated draft after some terrible news around about NASA dismissing these researches. They should not as, otherwise, it could happen as with Galilei having his detractors even not trying to look in the telescope, just dismissing on faith.I have analysed the case of the frustum and the results appear to be striking. One must admit that geometry comes to rescue not just general relativity. For this particular geometry the cavity can be made susceptible to gravitational effects if your choice of the two radii of the cavity is smart enough. This is something to be confirmed yet, just my theoretical result, but shocking anyway.As usual, any comment is very welcome.In page 8, equation 34 of http://forum.nasaspaceflight.com/index.php?action=dlattach;topic=36313.0;attach=830137, for the integral on dr', should the limits, instead of0 to ((r2-r1)/h) z' + r2ber1 to ((r2-r1)/h) z' + r1 ?
I am back with an updated draft after some terrible news around about NASA dismissing these researches. They should not as, otherwise, it could happen as with Galilei having his detractors even not trying to look in the telescope, just dismissing on faith.I have analysed the case of the frustum and the results appear to be striking. One must admit that geometry comes to rescue not just general relativity. For this particular geometry the cavity can be made susceptible to gravitational effects if your choice of the two radii of the cavity is smart enough. This is something to be confirmed yet, just my theoretical result, but shocking anyway.As usual, any comment is very welcome.
Quote from: deltaMass on 05/16/2015 01:52 amYes. And the way to silence sceptics is to make measurements on a fully-boxed rig - including battery. All these trailing feeds generate pseudo-forces. That would be OK if thrust were Newton level - but it ain't, so it ain't.The Dynamic Tests of the EM Drive showed a slowly rotating table top of machinery. So sufficient force was being produced to move the equipment 2 metres in a few minutes.
Quote from: A_M_Swallow on 05/16/2015 02:42 amQuote from: deltaMass on 05/16/2015 01:52 amYes. And the way to silence sceptics is to make measurements on a fully-boxed rig - including battery. All these trailing feeds generate pseudo-forces. That would be OK if thrust were Newton level - but it ain't, so it ain't.The Dynamic Tests of the EM Drive showed a slowly rotating table top of machinery. So sufficient force was being produced to move the equipment 2 metres in a few minutes.A constant force produces a constant acceleration, unless you are prepared to abandon Isaac-baby. Where was it? Coupled [sic] with which, the table contained several rotating devices like fans and a hard drive.
Quote from: WarpTech on 05/15/2015 07:25 pmQuote from: deltaMass on 05/15/2015 07:13 pmThe competitionhttp://nextbigfuture.com/2015/05/photonic-laser-thruster-has-moved-one.htmlThat's what I'm talking about! Something like this would be at least 20% more efficient than an EM Drive could ever be. IMO, no competition... Todd D.How do you figure that?
Quote from: deltaMass on 05/15/2015 07:13 pmThe competitionhttp://nextbigfuture.com/2015/05/photonic-laser-thruster-has-moved-one.htmlThat's what I'm talking about! Something like this would be at least 20% more efficient than an EM Drive could ever be. IMO, no competition... Todd D.
The competitionhttp://nextbigfuture.com/2015/05/photonic-laser-thruster-has-moved-one.html
Anyone seen this little tidbit?http://phys.org/news/2015-05-newton-law-broken.html
Quote from: deltaMass on 05/16/2015 03:27 amQuote from: A_M_Swallow on 05/16/2015 02:42 amQuote from: deltaMass on 05/16/2015 01:52 amYes. And the way to silence sceptics is to make measurements on a fully-boxed rig - including battery. All these trailing feeds generate pseudo-forces. That would be OK if thrust were Newton level - but it ain't, so it ain't.The Dynamic Tests of the EM Drive showed a slowly rotating table top of machinery. So sufficient force was being produced to move the equipment 2 metres in a few minutes.A constant force produces a constant acceleration, unless you are prepared to abandon Isaac-baby. Where was it? Coupled [sic] with which, the table contained several rotating devices like fans and a hard drive.You're right it was with hard drives and fans, but weren't they running before they switched on the EM Drive?
Quote from: deltaMass on 05/15/2015 07:55 pmQuote from: WarpTech on 05/15/2015 07:25 pmQuote from: deltaMass on 05/15/2015 07:13 pmThe competitionhttp://nextbigfuture.com/2015/05/photonic-laser-thruster-has-moved-one.htmlThat's what I'm talking about! Something like this would be at least 20% more efficient than an EM Drive could ever be. IMO, no competition... Todd D.How do you figure that?Because, IMO the EM Drive has no thrust without losses. Resonating modes do not exert any NET force. It is the attenuation of evanescent modes that provide whatever thrust can be had.
Quote from: SeeShells on 05/16/2015 03:56 amAnyone seen this little tidbit?http://phys.org/news/2015-05-newton-law-broken.htmlSorry, but, as one commenter notes: "Egregious click-bait"
I'm glad someone understands how the EmDrive works!!
Quote from: Notsosureofit on 05/16/2015 01:02 amQuote from: Rodal on 05/16/2015 12:57 amQuote from: StrongGR on 05/14/2015 06:00 pmI am back with an updated draft after some terrible news around about NASA dismissing these researches. They should not as, otherwise, it could happen as with Galilei having his detractors even not trying to look in the telescope, just dismissing on faith.I have analysed the case of the frustum and the results appear to be striking. One must admit that geometry comes to rescue not just general relativity. For this particular geometry the cavity can be made susceptible to gravitational effects if your choice of the two radii of the cavity is smart enough. This is something to be confirmed yet, just my theoretical result, but shocking anyway.As usual, any comment is very welcome.In page 8, equation 34 of http://forum.nasaspaceflight.com/index.php?action=dlattach;topic=36313.0;attach=830137, for the integral on dr', should the limits, instead of0 to ((r2-r1)/h) z' + r2ber1 to ((r2-r1)/h) z' + r1 ?Good Point ! But volume integral ? 0 to ... ((r2-r1)/h) z' + r1 /l0 ? (seems circular that way)It's Eq. 18 that still bothers me a bit. Invoking the Heaviside step function is OK, but I don't see the addl. components being detectable outside the cavity w/o a non-linear term. Maybe I'm missing something ?1) Good point about Eq. 18: how do those harmonic components make it outside the cavity? Do they go outside the cavity because of the small transparent portholes on the EM Drive through which the interferometer laser beam is going through?2) If one wants to nondimensionalize the expression, it would have to ber1/lo to ((r2-r1)/h) z'/l0 + r1 /l0 instead of 0 to ((r2-r1)/h) z' + r1 /l0and since zbar= z/l0zbar' = z'/l0thenr1 /l0 to (r2-r1)/h) zbar' + r1 /l0 but the last integral would have to be on drbar' instead of on dr'and the first integral would have to be on dzbar' instead of on dz, and the first integral would have to be over0 to h/loinstead of0 to h