Quote from: txdrive on 06/01/2015 02:33 amNot that this all matters, because 1: Shawyer's formula for computing thrust has been definitely falsified by EagleWorks down to 1..2%EW did not use the correct excitation frequency as per the SPR resonance method, so nothing is disproven.
Not that this all matters, because 1: Shawyer's formula for computing thrust has been definitely falsified by EagleWorks down to 1..2%
Quote from: TheTraveller on 06/01/2015 02:48 amQuote from: txdrive on 06/01/2015 02:33 amNot that this all matters, because 1: Shawyer's formula for computing thrust has been definitely falsified by EagleWorks down to 1..2%EW did not use the correct excitation frequency as per the SPR resonance method, so nothing is disproven.They tried a whole bunch of resonant modes, at resonance. They really really tried hard to see thrust where there isn't any (to the point of seeing thrust into their errors, at least for now, but I'm sure it'll eventually get resolved)
Quote from: txdrive on 06/01/2015 02:51 amQuote from: TheTraveller on 06/01/2015 02:48 amQuote from: txdrive on 06/01/2015 02:33 amNot that this all matters, because 1: Shawyer's formula for computing thrust has been definitely falsified by EagleWorks down to 1..2%EW did not use the correct excitation frequency as per the SPR resonance method, so nothing is disproven.They tried a whole bunch of resonant modes, at resonance. They really really tried hard to see thrust where there isn't any (to the point of seeing thrust into their errors, at least for now, but I'm sure it'll eventually get resolved)But did they ask Shawyer? I mean they were trying to replicate his EM Drive, getting nowhere but seemingly ignoring his equations and methods to calc frustum resonance at virtually any TX,m,n,p mode you desire.As you can see from my EM Drive Calculator, the process is simple and straight forward.
At the risk of repeating every competent physicist that ever came into this thread: Shawyer's calculations are completely confused even in simplest details. There's no point of contact between what he's doing and the discipline known as "physics".
Quote from: TheTraveller on 06/01/2015 02:55 amQuote from: txdrive on 06/01/2015 02:51 amQuote from: TheTraveller on 06/01/2015 02:48 amQuote from: txdrive on 06/01/2015 02:33 amNot that this all matters, because 1: Shawyer's formula for computing thrust has been definitely falsified by EagleWorks down to 1..2%EW did not use the correct excitation frequency as per the SPR resonance method, so nothing is disproven.They tried a whole bunch of resonant modes, at resonance. They really really tried hard to see thrust where there isn't any (to the point of seeing thrust into their errors, at least for now, but I'm sure it'll eventually get resolved)But did they ask Shawyer? I mean they were trying to replicate his EM Drive, getting nowhere but seemingly ignoring his equations and methods to calc frustum resonance at virtually any TX,m,n,p mode you desire.As you can see from my EM Drive Calculator, the process is simple and straight forward.At the risk of repeating every competent physicist that ever came into this thread: Shawyer's calculations are completely confused even in simplest details. There's no point of contact between what he's doing and the discipline known as "physics".
Quote from: txdrive on 06/01/2015 03:00 amAt the risk of repeating every competent physicist that ever came into this thread: Shawyer's calculations are completely confused even in simplest details. There's no point of contact between what he's doing and the discipline known as "physics".Yet SPR and the Chinese calculate resonance their way and measure significant thrust, while EW, following their conventional COMSOL approach, see nothing.4 to 6 weeks from now, I'll open up the streaming links and you can watch to see if there is thrust or not.
I don't believe "streaming links" will convince me that Shawyer's experiments show any thrust. Youtube has a lot of that already. To convince me and any physicists who might be still reading your frequent posts you will have to supply raw test data and some proof that his experiments have been replicated. Extraordinary claims require extraordinary proof.
...What are you suggesting here, that EagleWorks didn't actually run the cavity at the resonance? From what I recall they had actually measured the Q with a sense antenna. There's a well known formula for calculating resonant modes of a truncated cone. It is certainly correct - tested to death in many practical devices. And they're also tuning the frequency to hit the actual resonance if the shape is a little off (due to thermal heating for instance).
Quote from: txdrive on 06/01/2015 03:00 am...What are you suggesting here, that EagleWorks didn't actually run the cavity at the resonance? From what I recall they had actually measured the Q with a sense antenna. There's a well known formula for calculating resonant modes of a truncated cone. It is certainly correct - tested to death in many practical devices. And they're also tuning the frequency to hit the actual resonance if the shape is a little off (due to thermal heating for instance).The point missing is, if you tune it for the highest Q and resonance, it reduces the thrust. I've proven to myself anyway, that the thrust happens due to the interference between the standing wave k and the evanescent wave Beta, phase factors. Where they interfere is where the phase shift is happening due to attenuation, as it propagates into the small end. Optimal thrust will occur when the amplitude of the standing waves is nearly the same as the amplitude of the evanescent waves and the two are out of phase. If you concentrate only on higher Q at resonance like EW did, it will minimize the evanescent waves that drive the thrust. Therefore, a lower Q is more likely to have positive results. Perhaps @TheTraveler's point is true, that had EW tested it at the Df frequency, it may have provided more thrust. So nothing is falsified by their test except the idea that they understand how it works.I'm still trying to crunch all this into design equations that are hopefully, more accurate and informative. It may take me a while.Todd
Quote from: WarpTech on 06/01/2015 04:42 amQuote from: txdrive on 06/01/2015 03:00 am...What are you suggesting here, that EagleWorks didn't actually run the cavity at the resonance? From what I recall they had actually measured the Q with a sense antenna. There's a well known formula for calculating resonant modes of a truncated cone. It is certainly correct - tested to death in many practical devices. And they're also tuning the frequency to hit the actual resonance if the shape is a little off (due to thermal heating for instance).The point missing is, if you tune it for the highest Q and resonance, it reduces the thrust. I've proven to myself anyway, that the thrust happens due to the interference between the standing wave k and the evanescent wave Beta, phase factors. Where they interfere is where the phase shift is happening due to attenuation, as it propagates into the small end. Optimal thrust will occur when the amplitude of the standing waves is nearly the same as the amplitude of the evanescent waves and the two are out of phase. If you concentrate only on higher Q at resonance like EW did, it will minimize the evanescent waves that drive the thrust. Therefore, a lower Q is more likely to have positive results. Perhaps @TheTraveler's point is true, that had EW tested it at the Df frequency, it may have provided more thrust. So nothing is falsified by their test except the idea that they understand how it works.I'm still trying to crunch all this into design equations that are hopefully, more accurate and informative. It may take me a while.ToddPlease correct me if I misunderstood but if the small end operates just above cutoff, as Shawyer suggests for highest Df and thrust, there will be no evanescent waves generated?
Remember that this is still a real physical system, there are no lines in the sand or brick walls over or through which nothing passes. This is using a noisy magnatron, there are frequencies both higher and lower than the design frequency. There will be evanescent waves created by the lower frequencies. The only penalty is that there may be fewer, at the cost of slightly higher resonance and/or lower power consumption. With those costs it becomes a trade-off as to which side of the cut-off to err on. Only careful experiments will determine that and we all hope that it doesn't end up requiring each EM thruster to be a custom device. We seek a model that will tell us exactly but we need careful experimentation to develop needed data for the model.
Some theories have thrust inversely proportional to frequency (hence this one at 24 GHz should have ~10 times less thrust than the ones at 2.4 GHz so far tested, based on inverse of linear proportionality alone)
I found this paper interesting:http://www.jpier.org/PIER/pier151/07.15022404.pdfFig 6-8"gradient force acting on a water drop of r = 10μm radius in a rectangular waveguide at the xy plane due to an evanescent wave"I understand that it is well known by specialists but the longer I take a look at all the stuff that is presented in this thread, the more fun it becomes (and my math is improving...