...From work on my spreadsheet, that can easily adopt to various TMm,n and TEm,n modes, I believe it is possible to get an excitation mode that will deliver a high Df, small end operating just above cutoff (as Shawyer recommends), without using stupid geometry...
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.
Quote from: TheTraveller on 05/28/2015 02:50 pm...From work on my spreadsheet, that can easily adopt to various TMm,n and TEm,n modes, I believe it is possible to get an excitation mode that will deliver a high Df, small end operating just above cutoff (as Shawyer recommends), without using stupid geometry...As you said that you care much more about experimental reports of thrust forces than about what a theory may predict, then this fact should be more important than what a spreadsheet may predict:Using a DesignFactor ~ 1 results in a Shawyer-formula predicted thrust outputForce = (2 * Power * Q * Df) /c = (2 * Power * Q ) /c for Df =1 for the Demonstrator at the maximum power tested of 1200 Watts and Q = 45000 and c= 299705000 m/s (speed of light in air) gives 360 milliNewtonsthat's 3.5 times the maximum thrust (102 milliNewtons) reported for the Demonstrator, so something is amiss with your spreadsheet calculation or with the data reported by Shawyer.
Quote from: JasonAW3 on 05/28/2015 01:05 pm@RodalApologies, but I thought that there'd already been some tests done in a vacume chamber with this device while still producing apparent thrust. Was I mistaken on this?If not, I would think that heated air convection would no longer be considered a potential factor in this device.The only organization, to my knowledge, that has reported tests in vacuum is NASA Eagleworks.Although Shawyer has been reporting tests for about 15 years and NPWU in China for several years, they have not reported tests in vacuum, to my knowledge.Since the tests results by NASA in vacuum were lower than the test results in air, it very much looks like the hypothesis that there is a significant thermal "gas effect" component involved in the tests is very much still alive, particularly when considering the much higher power used by Shawyer and NPWU in China.There is noting I have seen from the researchers that quantifies the size of this "gas effect" in the experiments conducted in air in the UK and China. Moreover, none of these tests have been conducted with a mesh for the ends, which is the only way that Cullen (who Shawyer uses as his main reference) found to eliminate the gas effect when performing tests in air in his 1951 Ph.D. thesis (the first time that anyone was able to quantitatively measure radiation pressure due to microwaves).That a significant gas effect component is present would not be surprising as it has been known since Maxwell in the 1870's that scientists trying to measure radiation pressure (at microwave and higher frequencies) have had to deal with such problems for over 100 years (these problems are collectively known as "the gas effect").
@RodalApologies, but I thought that there'd already been some tests done in a vacume chamber with this device while still producing apparent thrust. Was I mistaken on this?If not, I would think that heated air convection would no longer be considered a potential factor in this device.
Quote from: Rodal on 05/28/2015 01:25 pmQuote from: JasonAW3 on 05/28/2015 01:05 pm@RodalApologies, but I thought that there'd already been some tests done in a vacume chamber with this device while still producing apparent thrust. Was I mistaken on this?If not, I would think that heated air convection would no longer be considered a potential factor in this device.The only organization, to my knowledge, that has reported tests in vacuum is NASA Eagleworks.Although Shawyer has been reporting tests for about 15 years and NPWU in China for several years, they have not reported tests in vacuum, to my knowledge.Since the tests results by NASA in vacuum were lower than the test results in air, it very much looks like the hypothesis that there is a significant thermal "gas effect" component involved in the tests is very much still alive, particularly when considering the much higher power used by Shawyer and NPWU in China.There is noting I have seen from the researchers that quantifies the size of this "gas effect" in the experiments conducted in air in the UK and China. Moreover, none of these tests have been conducted with a mesh for the ends, which is the only way that Cullen (who Shawyer uses as his main reference) found to eliminate the gas effect when performing tests in air in his 1951 Ph.D. thesis (the first time that anyone was able to quantitatively measure radiation pressure due to microwaves).That a significant gas effect component is present would not be surprising as it has been known since Maxwell in the 1870's that scientists trying to measure radiation pressure (at microwave and higher frequencies) have had to deal with such problems for over 100 years (these problems are collectively known as "the gas effect").Rather than using vacuum or a mesh, it'd be preferable if they enclosed everything in an air-tight box that was suspended to make it insensitive to changes in centre of mass.Keep in mind also that (with Shawyer's formula) the net thrust may be stronger than a photon rocket but it is no stronger than a mirror (and with mirrors it is well known that effects due to heating are very huge comparing to pressure, unless very special conditions apply).Regarding the EagleWorks results (let's not tarnish NASA's reputation as a whole, please, with what most certainly will turn out to be a dud), their thrust is much less than predicted by Shawyer's formula, thus constituting a falsification. Shawyer's mistaken calculations of radiation pressure are not just theoretically wrong, they have been experimentally falsified by EagleWorks.Eagleworks also obtained no thrust without plastic inside the cavity, or when the plastic was not firmly in contact with the cavity wall, which would decrease heat conduction into the plastic but not affect EM fields otherwise.Now with regards to EagleWorks and their far smaller forces which don't replicate when turned around by 180 degrees: Their interpretation that it is a sum of some classical forces they don't understand with some anomalous novel physics they are discovering... well it leaves much to be desired. If they were quantifying their errors better they'd simply have something like 50uN ±100uN : a falsification of Shawyer's theory, and a multitude of classical forces that are known to arise at such power levels limiting the precision of said falsification. It took very smart people a long time to fully understand Crookes radiometer. edit: Throw in a couple tensioned leaf springs, heated by electrical current, some plastic the edges of which may be decomposing (strong electric field at a discontinuity in dielectric constant), plastic screws literally melting. Put it onto a non-vertical pendulum that is sensitive to shifts in CoM. Non-null findings of some kind are then guaranteed, and they're guaranteed to be very difficult to understand.
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.Using the following dimensions:Length: 138.6mmSmall diameter: 125.7mmBig diameter: 231.4mmand using the speed of light in air:cAir = 299705000 (meter/s)My exact solution gives:Mode: TE013Frequency: 3.94571 GHz
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: 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. Wow! Forces orders of magnitude greater than photon pressure of the illuminating laser - due to electron emmission.
Quote from: WarpTech on 05/28/2015 03:30 amThis says the imbalance on just the end plates is 100X more significant than those on the sidewalls. So my thought experiment is optimizing that end of it, so to speak. ...Maybe we should setup a listing of the proposed theories/conjectures we got so far and how we could experimentally test them individually? if they fail, you can scrap the theory and move to the next one...
This says the imbalance on just the end plates is 100X more significant than those on the sidewalls. So my thought experiment is optimizing that end of it, so to speak.
Quote from: TheTraveller on 05/28/2015 05:33 pmQuote from: Rodal on 05/28/2015 05:23 pmQuote 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.Using the following dimensions:Length: 138.6mmSmall diameter: 125.7mmBig diameter: 231.4mmand using the speed of light in air:cAir = 299705000 (meter/s)My exact solution gives:Mode: TE013Frequency: 3.94571 GHzThe results data I received from Roger was from the SPR inhouse EM Drive design & development software suite.WARNING It looks like you are aiming for a degenerate natural frequency as this Transverse Magnetic mode has the same natural frequency:TM113as TE013
Quote from: Rodal on 05/28/2015 05:23 pmQuote 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.Using the following dimensions:Length: 138.6mmSmall diameter: 125.7mmBig diameter: 231.4mmand using the speed of light in air:cAir = 299705000 (meter/s)My exact solution gives:Mode: TE013Frequency: 3.94571 GHzThe results data I received from Roger was from the SPR inhouse EM Drive design & development software suite.
Quote from: aero on 05/28/2015 05:19 pmQuote 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. Wow! Forces orders of magnitude greater than photon pressure of the illuminating laser - due to electron emmission.What about the growing positive charge that develops on the thruster? It seems there will be necessary to inject protons into the electron jet to maintain neutrality of charge.
...Maybe from The Traveller - Mulletron - SeeShell (if she bulids one) - or one of several others to numerous to mention. Do we have a list anywhere of all of the DIY efforts ongoing or planned?
Quote from: MyronQG on 05/28/2015 05:35 pmQuote from: aero on 05/28/2015 05:19 pmQuote from: Paul Novy on 05/28/2015 07:49 amMaybe from The Traveller - Mulletron - SeeShell (if she bulids one) - or one of several others to numerous to mention. Do we have a list anywhere of all of the DIY efforts ongoing or planned?I am working on building one. I have an idea that I'm still working on that's a little bit different than anything else. I'm still working out details of the build and design. At my age I can't afford redos or mistakes so I'm slowly working through the details. Not quite ready to release it for peer consumption. Thanks for remembering me, it means someone is listening to my babbling. Shell
Quote from: aero on 05/28/2015 05:19 pmQuote from: Paul Novy on 05/28/2015 07:49 amMaybe from The Traveller - Mulletron - SeeShell (if she bulids one) - or one of several others to numerous to mention. Do we have a list anywhere of all of the DIY efforts ongoing or planned?I am working on building one. I have an idea that I'm still working on that's a little bit different than anything else. I'm still working out details of the build and design. At my age I can't afford redos or mistakes so I'm slowly working through the details. Not quite ready to release it for peer consumption. Thanks for remembering me, it means someone is listening to my babbling. Shell
Quote from: Paul Novy on 05/28/2015 07:49 amMaybe from The Traveller - Mulletron - SeeShell (if she bulids one) - or one of several others to numerous to mention. Do we have a list anywhere of all of the DIY efforts ongoing or planned?I am working on building one. I have an idea that I'm still working on that's a little bit different than anything else. I'm still working out details of the build and design. At my age I can't afford redos or mistakes so I'm slowly working through the details. Not quite ready to release it for peer consumption. Thanks for remembering me, it means someone is listening to my babbling. Shell
Maybe from The Traveller - Mulletron - SeeShell (if she bulids one) - or one of several others to numerous to mention. Do we have a list anywhere of all of the DIY efforts ongoing or planned?
I accept the challenge! http://emdrive.echothis.com/List_of_Suggested_ExperimentsI'm going to work backwards through the threads. It will take me awhile to get everything listed. If you have a particular idea you'd like listed, just pm it to me and I'll add it immediately.
Quote from: WarpTech on 05/28/2015 03:30 amThis says the imbalance on just the end plates is 100X more significant than those on the sidewalls. So my thought experiment is optimizing that end of it, so to speak. On condition of course that it is really the case, wouldn't it make sense then to use "metglas" on the (small?) endplate, because it has a dramatically increased magnetic permeability, compared to copper?(x1000000)Wouldn't that greatly amplify that magnetic imbalance then?http://en.wikipedia.org/wiki/Permeability_%28electromagnetism%29It was talked about some 150 pages ago or so, but it fell between the cracks...IF we assume that the EMdrive gets validated as a thrust generating device, I think we should try to setup some experimental parameters that will test each of the proposed theories on their validity.Maybe we should setup a listing of the proposed theories/conjectures we got so far and how we could experimentally test them individually? if they fail, you can scrap the theory and move to the next one...