While stumbling through Shawyer's papers, I reached the conclusion that his thrust equation, after substituting the parameter names that Prof. M used, is:T = 2*S_{o} * P*Q/c *(RF wavelength/w_big - RF wavelength/w_small) orT = 2*S_{o} *P*Q/f *(1/w_big - 1/w_small)where S_{o} = (1 - (RF wavelength^2)/(w_big*w_small))^-1In other words, Shawyer's thrust model differs from Prof. M's thrust model by a multiplicative factor of 2*So .That of course assumes that I interpreted Shawyer's definition of terms correctly.

As a veteran member of the American Statistical Association...

Quote from: some random guy on an intertube thread...As a veteran member of the American Statistical Association...Oh right. Everybody knows that the chances of a coin landing on its edge are fifty-fifty. You gotta have better credentials than that!

Quote from: JohnFornaro on 10/16/2014 12:49 pmQuote from: some random guy on an intertube thread...As a veteran member of the American Statistical Association...Oh right. Everybody knows that the chances of a coin landing on its edge are fifty-fifty. You gotta have better credentials than that!I thought those were the chances of a coin landing head or tails?

does this pertain?arxiv.org/pdf/1312.3267

...I get. Shawyer Experimental DemonstratorDimension - meters metersw_big, in. 0.1600 0.2800 w_small, in 0.1050 0.0778 height, in 0.1700 0.3811 w_small, external view. 0.1711 The Demonstrator has a constant external small end diameter for about half the length. I speculate that the taper continues internally with the constant diameter section there for whatever reason. That constant diameter section is about 0.1711 meter. Did the Chinese do both sizes?Edit: I don't think you should use demonstrator numbers. W_big is OK, it's from the text but w_small is probably to small and height to large. I expect the taper stops in the cylindrical section at a height of about 300 mm based on the Experimental and Eagleworks device ratios.. Point is, I can't tell the dimensions of the demonstration device cavity because of the construction. Garbage in, garbage out so just don't use the above Demonstrator numbers I guess.

An interpretation of Shawyer's Lambda0 as RF wavelength would lead to a factor of 2 / (1 - (RF wavelength^2)/(w_big*w_small)) ~ 6 for NASA's truncated cone, multiplying the present equation, leading to predicted forces that would be 6 times larger than the experimentally measured ones.

Quote from: JohnFornaro on 10/16/2014 02:27 pmdoes this pertain?arxiv.org/pdf/1312.3267Pertain? We're sorry all attendants are still busy...

In this case the scientific/engineering judgement comes in knowing what is the difference in mode shapes between the geometry below and the geometry of a perfect truncated cone. I made that assessment, so I included the NASA Eagleworks truncated cones and both Shawyer truncated cones in the data. What matters mostly are the flat base surfaces of the truncated cone. This is supported by the data I have previously shown.

@RodalQuoteIn this case the scientific/engineering judgement comes in knowing what is the difference in mode shapes between the geometry below and the geometry of a perfect truncated cone. I made that assessment, so I included the NASA Eagleworks truncated cones and both Shawyer truncated cones in the data. What matters mostly are the flat base surfaces of the truncated cone. This is supported by the data I have previously shown.Ok. If I assume the cavity shape of the Demonstrator is the same shape as the Experimental model, then using the published text numbers for the overall diameters, 280 mm and 160 mm, by ratio I calculate the Demonstrator dimensions as:w_big = 0.28 metersw_small = 0.18375 metersheight = 0.2975 metersThese are most likely usable numbers but feel free to use the best data you have available.My problem with this is, "How does he justify larger dimensions on the resonate cavity while using the same or higher frequency drive?" It must be buried in his theory somewhere.

Ok.Now, didn't you show that thrust was not strongly dependent on frequency? But photon momentum is strongly dependent on frequency (as is energy) so does this imply that thrust is not strongly dependent on photon momentum? Or can your approach separate momentum and energy?

Quote from: aero on 10/16/2014 06:11 pmOk.Now, didn't you show that thrust was not strongly dependent on frequency? But photon momentum is strongly dependent on frequency (as is energy) so does this imply that thrust is not strongly dependent on photon momentum? Or can your approach separate momentum and energy?No, what I showed was that the variation with frequency overwhelmed the ability to regress the data because of the nonlinearity of the amplitude vs frequency curve and the paucity of frequency data.On the contrary, the measured thrust is most dependent on amplitude of the resonance curve and the amplitude is very nonlinearly dependent on frequency.

Quote from: Rodal on 10/16/2014 06:16 pmQuote from: aero on 10/16/2014 06:11 pmOk.Now, didn't you show that thrust was not strongly dependent on frequency? But photon momentum is strongly dependent on frequency (as is energy) so does this imply that thrust is not strongly dependent on photon momentum? Or can your approach separate momentum and energy?No, what I showed was that the variation with frequency overwhelmed the ability to regress the data because of the nonlinearity of the amplitude vs frequency curve and the paucity of frequency data.On the contrary, the measured thrust is most dependent on amplitude of the resonance curve and the amplitude is very nonlinearly dependent on frequency.Ok that makes sense.

...McCulloc's formula is indicated with the arrow, stars show decent candidates.We note that all selected solutions with both a decent absolute magnitude (mean near 0) and low deviation all share the same factors F = Q P/c times something in meters^-1. This geometric factor, (1/b - 1/a) for McCulloch, allows for a lot of variations while still giving correct predictions. This is not surprising since L and a and b all are in a comparable range, this is hard to confirm a clear relation. While (1/b - 1/a) has a good look compared to others, I wouldn't say we have to explain why we should have this particular formula. More data required. On the other hand the QP/c term (and probably QPL/c) seems a clear winner to be accounted for.