If a space-based test is to merely indicate whether an EmDrive provides thrust, then all that's required is to establish a time correlation between drive power on/off activity and measured acceleration.
I find it laughable to even talk about spaceships and missions without even having an established and widely accepted, repeatable science behind it. It baffles me to read time and again that Mr. Shawyer is sitting on the holy grail of propulsion, but doesn't seem to be willing to publicly present a current device that produces Newtons of thrust, as claimed by him since quite a long time now.
Quote from: CW on 07/18/2015 03:53 pmI find it laughable to even talk about spaceships and missions without even having an established and widely accepted, repeatable science behind it. It baffles me to read time and again that Mr. Shawyer is sitting on the holy grail of propulsion, but doesn't seem to be willing to publicly present a current device that produces Newtons of thrust, as claimed by him since quite a long time now.I respectfully disagree on both points. Regarding hypothetical mission profiles, I've been reading about https://en.wikipedia.org/wiki/Alcubierre_drive Alcubierre Drives for two decades. Mars Direct mission profiles based on uninvented but plausible technology have been around a very long time as well. Add to this uncountable hours of fantasy around warp drives, wormholes, and other means of faster-than light travel. How is this substantively different or less outrageous than hypothetical emdrive mission profiles based on thrust levels within a few orders of magnitude of what you can build in your own garage with microwave oven parts? Without these dreams space is just a big expensive empty place.To your second point, Mr. Shawyer has been shouting from rooftops for a decade about patented working and demonstrable technology. He has been conspicuously ignored, laughed at, and called charlatan fraud. On this very forum are people who, despite zero effort in replication, deride emdrive technology as an impossible unworkable fools errand. Parallel to this you have the folks over at the Cannae drive shop who have managed to patent core emdrive technology that stomps all over over Mr. Shawyer's existing IP. If SPR believes it is in their best interest to not publish any more data or share their newest work then that is their hard earned and battle-won prerogative.Respectfully.
I notice that the Aachen boys have gone quiet.
According to present data, testing the EMDrive with input powers at or above 1 MW is necessary to reach a thrust that can actually be experienced without doubt of measurement errors. Achieving a thrust level high enough to lift an object would (as done by Goddard with chemical rockets) finally convince people to adequately fund R&D in this area.Let us gather enough supporters to send an E-Mail to Mythbusters.They definitely have the money and means to use a Gyrotron, Klystron or a similar powerful microwave source and build a simple truncated cone microwave resonator to see whether they can achieve a level of thrust high enough to convince people to fund adequate R&D in this area.
The Space Show has posted this coming week's newsletter, and:* Tuesday, July 21, 2015; 7-8:30 PM PDT (10-11:30 PM EDT): Dr. JIM WOODWARD back to update us on his work with a Mach effect drive impulse engine and gravitational physics.~Kirkz
Meepers...here's a video that describes my antenna placement in NSF-1701:
For a comparison of time to reach "steady state" from a completely different model of the EM Drive, here is Dr. White's Quantum Vacuum code calculations (last slide I remember seeing):Notice: Dr. White QV code Meep rfmwguy "NSF 1701"Time step 7.17 picoseconds 2.001 picosecondsMax time run 1.076 microseconds 0.013 microsecondsMax # steps run 150,000 6,527That's a hundred times longer than what Meep has been run up to now. We see the recurring theme that one needs to run a simulation to at least 1 microsecond duration.
Quote from: Rodal on 07/20/2015 01:10 amFor a comparison of time to reach "steady state" from a completely different model of the EM Drive, here is Dr. White's Quantum Vacuum code calculations (last slide I remember seeing):Notice: Dr. White QV code Meep rfmwguy "NSF 1701"Time step 7.17 picoseconds 2.001 picosecondsMax time run 1.076 microseconds 0.013 microsecondsMax # steps run 150,000 6,527That's a hundred times longer than what Meep has been run up to now. We see the recurring theme that one needs to run a simulation to at least 1 microsecond duration.tidux can get the current meep model done in about 45 minutes with 8 threads out of his 12 threads. Considering it scales linearly, he could get a performance of 30 minutes.So, <0.5 hour / 0.013 microseconds>. So it would take tidux's server just a little bit over 2 days to complete 1.3 microseconds, which is completely reasonable on my opinion. Do you believe it would be a good use for his server, Doctor Rodal? And what do you think, Mister tidux?
Alright - here we go.With help from tidux and leomillert I am reporting my results of running meep-mpi against the NSF-1701.ctl file attached.The zCopper-exy.csv that I produce is different from the file I've been comparing it to from Aero - I took it from https://drive.google.com/folderview?id=0B1XizxEfB23tfmkxNm1Ha1YxR1NZU2ZjUUpBUVVGV0M4QUVxaGYySEVFam5jVzdRYy0tSWs&usp=sharing the file zCopper-exy.csv.Aero's file has 247 rows, and mine produces 245. Aero's file has jd columns, mine has ja. However, I get the same results as tidux.Attached is the NSF-1701.ctl file I used, and a three-sheet spreadsheet (zCopper-exy-eer1p.ods) holding (a) my zCopper-exy-eer1p sheet, (b) tidux' NSF-1701-normal-zCopper-exy sheet, and (c) a Delta sheet calculating the difference of each cell of (a) and (b). There are no differences. The value in the Delta cell A247 is the max(a1:ja245), which is zero.So - tidux and I match. Either I am comparing to the wrong csv file from Aero, or we're out of sync in some other way.For comparison, a second spreadsheet - zCopper-exy-aero.ods - compares my zCopper-exy-eer1p to Aero's zCopper-exy-aero sheets in a Delta sheet. There, cell A249 shows the max of the absolute value of cell differences to be 0.004464033.Please advise whether my results are accurate enough to contribute further.I also suggest we get into a pattern of reporting results with a copy of the control file used and whatever output files we provide, all associated in some way (in a directory or zip file) noting a name or description of the run, who ran it, and when it was run (perhaps those things should be recorded on a data description sheet also included with the control run and output files).Configuration management is about to be important, here, tracking inputs, outputs, and the configurations used to perform them (so they can be reproduced upon need).Surely there are experimental data procedures already defined and well used by various communities for such things.Note - I'm uploading ods format spreadsheet files because (a) we're all using Linux and so Open Office in one form or another is readily available to us all there, (b) when I tried to save in xls format - the older Excel format - it seems there were too many columns to be saved, so I switched to ods. I believe that current Excel product from Microsoft can read ods files.Ed
.....Just got this looks sweet.
Quote from: SeeShells on 07/19/2015 07:31 pm.....Just got this looks sweet.The SA0314 looks very interesting. Price is good.http://www.rfinstruments.com/php/pdf/SA0314%20datasheet.pdfYou should be able to measure and record the output power bandwidth of your magnetron and if you barely insert the tip of a probe inside your frustum (good to put in some attenuation so you don't blow the input stage of the spectrum analyser), should see the acceptance bandwidth of your frustum and record. Can then compare the charts to work out which of the magnetron frequencies are being accepted by your frustum and which are being rejected.Is that how you plan to use this?