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There is anotherThis is the best place to comment so I'll go aheadAMAP device today measured 22 micro Newtons from 4,5 watt input. Weighing 500 grams the first protoype is nowhere near its potential.
Quote from: ludkokanta on 07/06/2015 03:33 pmThere is anotherThis is the best place to comment so I'll go aheadAMAP device today measured 22 micro Newtons from 4,5 watt input. Weighing 500 grams the first protoype is nowhere near its potential.Excuse my french, but i find that rather ...euhm.. unimpressive ?Unless there is a confusing between mN or µN, your device delivers 4.8 mN per kW, where as dr.Yang's EMdrive experiment (best results so far) reported 1070 mN per kW....Some serious energy/efficiency gap there to bridge...
Quote from: aero on 07/06/2015 05:20 pmQuote from: Rodal on 07/06/2015 03:11 pmQuote from: aero on 07/06/2015 03:04 pm...I'll see what I can do.Meep documentation says that Meep uses "pervasive" interpolation, or some word like that. Implying that when a value not on a grid point is needed, weighted average of adjacent points is calculated.Yes, that's what Meep did (interpolation), as I show in the plots above. But it is not optimal, as I also show what happens at location 207 (double peak). It is much better to have gridpoints along the longitudinal axis, so if you ever re-mesh I suggest to take the opportunity to have an odd number of rows with gridpoints along the longitudinal axis. It is only at Finite Difference gridpoints in a Finite Difference solution that one can control the solution (imposing conditions at gridpoints).I seem to have misplaced the h5 files needed to generate the csv files for the case you are interested in, so I'll need to re-run it. Shall I go ahead and recreate and upload the complete data set with a new mesh, or try to match the data that I already used. (I'm a little concerned that I may have changed the antenna length).Rerunning and uploading the complete data set won't take as much effort as it did the first time because using my new file naming convention I can do it all en-mass, without the need to keep the default identically named .csv files in separate identifying folders.Your call. I'm leaning toward the latter to avoid any concern about inconsistent data.I vote for re-running with a slightly different mesh such that it has gridpoints in the longitudinal direction (an odd number of equi-distant rows). Antenna location the same (near the small end). Orientation the same (if I recall correctly source was Ez but it was oriented along y ? -please double check). Copper model.
Quote from: Rodal on 07/06/2015 03:11 pmQuote from: aero on 07/06/2015 03:04 pm...I'll see what I can do.Meep documentation says that Meep uses "pervasive" interpolation, or some word like that. Implying that when a value not on a grid point is needed, weighted average of adjacent points is calculated.Yes, that's what Meep did (interpolation), as I show in the plots above. But it is not optimal, as I also show what happens at location 207 (double peak). It is much better to have gridpoints along the longitudinal axis, so if you ever re-mesh I suggest to take the opportunity to have an odd number of rows with gridpoints along the longitudinal axis. It is only at Finite Difference gridpoints in a Finite Difference solution that one can control the solution (imposing conditions at gridpoints).I seem to have misplaced the h5 files needed to generate the csv files for the case you are interested in, so I'll need to re-run it. Shall I go ahead and recreate and upload the complete data set with a new mesh, or try to match the data that I already used. (I'm a little concerned that I may have changed the antenna length).Rerunning and uploading the complete data set won't take as much effort as it did the first time because using my new file naming convention I can do it all en-mass, without the need to keep the default identically named .csv files in separate identifying folders.Your call. I'm leaning toward the latter to avoid any concern about inconsistent data.
Quote from: aero on 07/06/2015 03:04 pm...I'll see what I can do.Meep documentation says that Meep uses "pervasive" interpolation, or some word like that. Implying that when a value not on a grid point is needed, weighted average of adjacent points is calculated.Yes, that's what Meep did (interpolation), as I show in the plots above. But it is not optimal, as I also show what happens at location 207 (double peak). It is much better to have gridpoints along the longitudinal axis, so if you ever re-mesh I suggest to take the opportunity to have an odd number of rows with gridpoints along the longitudinal axis. It is only at Finite Difference gridpoints in a Finite Difference solution that one can control the solution (imposing conditions at gridpoints).
...I'll see what I can do.Meep documentation says that Meep uses "pervasive" interpolation, or some word like that. Implying that when a value not on a grid point is needed, weighted average of adjacent points is calculated.
...I have re-meshed, does 245x261x261 sound good?I'll run the 10.2 inch copper model at freq. = 2.45 GHz, BW = 0.025 * freq.58 mm dipole antenna, 1/4 wavelength from the inside face of the small end, centered and lying along a y diameter.
Quote from: Flyby on 07/06/2015 09:36 pmQuote from: ludkokanta on 07/06/2015 03:33 pmThere is anotherThis is the best place to comment so I'll go aheadAMAP device today measured 22 micro Newtons from 4,5 watt input. Weighing 500 grams the first protoype is nowhere near its potential.Excuse my french, but i find that rather ...euhm.. unimpressive ?Unless there is a confusing between mN or µN, your device delivers 4.8 mN per kW, where as dr.Yang's EMdrive experiment (best results so far) reported 1070 mN per kW....Some serious energy/efficiency gap there to bridge...1) His claimed results are in the same range as:NASA Brady, White, March, Lawrence, and Davies, aNASA Brady, White, March, Lawrence, and Davies, bIulian Berca Tests 3 & 3.1 (averaged w/up/down directional effects subtracted) 2) Neither Yang or Shawyer conducted their tests in vacuum (the NASA tests in vacuum are even lower than the figures given above in #1)3) It is my understanding from several second-hand sources that Prof. Tajmar, who has hundreds of articles published in peer-reviewed journals and does research for Airbus Defence and Space, will in a few days be presenting a paper at the AIAA reporting on thorough tests in vacuum at The Technische Universität Dresden, giving solid data even lower than #1 above. I suggest people attending his paper to ask him whether he views the tests done under vacuum at NASA and The Technische Universität Dresden as a nullification of the tests done by Yang and Shawyer at ambient conditions.4) Since Yang and Shawyer's never reported any tests done under vacuum, I suggest to hold on criticism until you have a chance to review the tests of Prof. Tajmar as a) NASA and The Technische Universität Dresden may be seen as more prestigious than NWPU and SPR, b) Tajmar has many more peer-reviewed papers, and c) only NASA and The Technische Universität Dresden appear to have conducted tests in vacuum.
...Also, did Dr. Tajmar treat his EM Drive as a thruster or a ratchet? According to SPR and TheTraveler, if he was expecting it to thrust, he probably got Null results as is to be expected, since it is not intended to thrust without some outside influence to make it ratchet.Todd
Regarding the question is my device an EM drive...It doesn't use propellant and can be used to drive space objects.It is different from the EM drive, however.Mine is better it appears.Both are relativity drives, both are a disproof od Newtons third (which is something special relativity should have taught us), both partially "externalize" impulse and reduce sealed system entropy by doing so.
I thought I would chime in with questions for the AIAA conference. I am going to be attending the event, so I will be able to report back to you guys about what happens, other questions that were asked, etc. Let me know of a couple of definite questions that anyone would want me to ask during the Q and A, and I'll be sure to ask them and report back the answers. -I
Quote from: Rodal on 07/05/2015 01:04 pmQuote from: Rodal on 07/04/2015 06:00 pmQuote from: aceshigh on 06/22/2015 07:44 pmdid a search and did not find this... hope it was not posted yetQuoteAIAA Propulsion and Energy Forum and ExpositionHilton Orlando, Orlando, Florida...TUESDAY, JULY 28, 2015NFF-04. Future Flight Propulsion Systems...5:00 PM - 5:30 PMDirect Thrust Measurements of an EMDrive and Evaluation of Possible Side-EffectsMartin TajmarI wonder if someone from this thread could attend the conference and if there is a following Q/A, even mention some of the experiments discussed here, ask questions, etc.I am looking forward to this presentation. Unfortunately, I won't be attending. I have tried to find out, from several different second-hand sources what has been the nature of Martin Tajmar's experiments. It is my personal understanding that his EM Drive experiments have shown very low force/InputPower readings for an EM Drive in a partial vacuum: less than a few dozen or so times the force/InputPower of a perfectly collimated photon rocket, thus much lower thrust force/InputPower than Yang (who reported 300,000 times a photon rocket) and Shawyer (25,000 to 70,000 times) have reported. I understand that the quality factor of resonance (Q) in the experiments is extremely low, much lower than any researcher has reported up to now. Regarding possible questions to ask if anybody attends, one suggestion (if this is what is reported) is to ask why is his experimental Q so low (less than 100): how could the experiments have been conducted under resonance if the Q was so low?. Another question: what was responsible for such a low Q in the experiments, and whether Tajmar thinks that the discrepancy with other researchers has to do with the different Q reported from different researchers.Another suggested question to Prof. Tajmar: given the very low force/InputPower readings for an EM Drive in a partial vacuum measured by Prof. Tajmar (less than a few dozen or so times the force/InputPower of a perfectly collimated photon rocket), does Prof. Tajmar see his (and Georg Fiedler's) experiments at The Technische Universität Dresden as a scientific nullification of the claims made by Yang and Shawyer, since Yang and Shawyer claim over 1,000 to 10,000 times greater force/InputPower than what Tajmar measured) ?Does Prof. Tajmar think that the reason why Shawyer and Yang claimed much higher thrust is because Shawyer and Yang reported tests at ambient pressure (unlike Prof. Tajmar who has performed his tests in a vacuum), and Shawyer and Yang just reported thermal convection artifacts?If, not a nullification due to Shawyer and Yang not performing tests in vacuum, what does Prof. Tajmar think that the huge difference (1,000 to 10,000 times) is due to ?Another suggested question to ask Tajmar (apparently their experimental measurements at some point showed some 60% orientation dependence if my understanding is correct, not clear whether experimental noise, and whether he will present some updated data):QUESTION: why did the experiments show approximately 60% different thrust force measurements when the EM Drive was physically rotated 180 degrees from the "forward" thrust tests to the "reverse" thrust tests? Shouldn't the thrust be the same regardless of space orientation? Is this orientation-dependence indicative of an experimental artifact or a dependence on an external field ?
Quote from: Rodal on 07/04/2015 06:00 pmQuote from: aceshigh on 06/22/2015 07:44 pmdid a search and did not find this... hope it was not posted yetQuoteAIAA Propulsion and Energy Forum and ExpositionHilton Orlando, Orlando, Florida...TUESDAY, JULY 28, 2015NFF-04. Future Flight Propulsion Systems...5:00 PM - 5:30 PMDirect Thrust Measurements of an EMDrive and Evaluation of Possible Side-EffectsMartin TajmarI wonder if someone from this thread could attend the conference and if there is a following Q/A, even mention some of the experiments discussed here, ask questions, etc.I am looking forward to this presentation. Unfortunately, I won't be attending. I have tried to find out, from several different second-hand sources what has been the nature of Martin Tajmar's experiments. It is my personal understanding that his EM Drive experiments have shown very low force/InputPower readings for an EM Drive in a partial vacuum: less than a few dozen or so times the force/InputPower of a perfectly collimated photon rocket, thus much lower thrust force/InputPower than Yang (who reported 300,000 times a photon rocket) and Shawyer (25,000 to 70,000 times) have reported. I understand that the quality factor of resonance (Q) in the experiments is extremely low, much lower than any researcher has reported up to now. Regarding possible questions to ask if anybody attends, one suggestion (if this is what is reported) is to ask why is his experimental Q so low (less than 100): how could the experiments have been conducted under resonance if the Q was so low?. Another question: what was responsible for such a low Q in the experiments, and whether Tajmar thinks that the discrepancy with other researchers has to do with the different Q reported from different researchers.Another suggested question to Prof. Tajmar: given the very low force/InputPower readings for an EM Drive in a partial vacuum measured by Prof. Tajmar (less than a few dozen or so times the force/InputPower of a perfectly collimated photon rocket), does Prof. Tajmar see his (and Georg Fiedler's) experiments at The Technische Universität Dresden as a scientific nullification of the claims made by Yang and Shawyer, since Yang and Shawyer claim over 1,000 to 10,000 times greater force/InputPower than what Tajmar measured) ?Does Prof. Tajmar think that the reason why Shawyer and Yang claimed much higher thrust is because Shawyer and Yang reported tests at ambient pressure (unlike Prof. Tajmar who has performed his tests in a vacuum), and Shawyer and Yang just reported thermal convection artifacts?If, not a nullification due to Shawyer and Yang not performing tests in vacuum, what does Prof. Tajmar think that the huge difference (1,000 to 10,000 times) is due to ?
Quote from: aceshigh on 06/22/2015 07:44 pmdid a search and did not find this... hope it was not posted yetQuoteAIAA Propulsion and Energy Forum and ExpositionHilton Orlando, Orlando, Florida...TUESDAY, JULY 28, 2015NFF-04. Future Flight Propulsion Systems...5:00 PM - 5:30 PMDirect Thrust Measurements of an EMDrive and Evaluation of Possible Side-EffectsMartin TajmarI wonder if someone from this thread could attend the conference and if there is a following Q/A, even mention some of the experiments discussed here, ask questions, etc.I am looking forward to this presentation. Unfortunately, I won't be attending. I have tried to find out, from several different second-hand sources what has been the nature of Martin Tajmar's experiments. It is my personal understanding that his EM Drive experiments have shown very low force/InputPower readings for an EM Drive in a partial vacuum: less than a few dozen or so times the force/InputPower of a perfectly collimated photon rocket, thus much lower thrust force/InputPower than Yang (who reported 300,000 times a photon rocket) and Shawyer (25,000 to 70,000 times) have reported. I understand that the quality factor of resonance (Q) in the experiments is extremely low, much lower than any researcher has reported up to now. Regarding possible questions to ask if anybody attends, one suggestion (if this is what is reported) is to ask why is his experimental Q so low (less than 100): how could the experiments have been conducted under resonance if the Q was so low?. Another question: what was responsible for such a low Q in the experiments, and whether Tajmar thinks that the discrepancy with other researchers has to do with the different Q reported from different researchers.
did a search and did not find this... hope it was not posted yetQuoteAIAA Propulsion and Energy Forum and ExpositionHilton Orlando, Orlando, Florida...TUESDAY, JULY 28, 2015NFF-04. Future Flight Propulsion Systems...5:00 PM - 5:30 PMDirect Thrust Measurements of an EMDrive and Evaluation of Possible Side-EffectsMartin TajmarI wonder if someone from this thread could attend the conference and if there is a following Q/A, even mention some of the experiments discussed here, ask questions, etc.
AIAA Propulsion and Energy Forum and ExpositionHilton Orlando, Orlando, Florida...TUESDAY, JULY 28, 2015NFF-04. Future Flight Propulsion Systems...5:00 PM - 5:30 PMDirect Thrust Measurements of an EMDrive and Evaluation of Possible Side-EffectsMartin Tajmar
Quote from: aero on 07/06/2015 10:13 pm...I have re-meshed, does 245x261x261 sound good?I'll run the 10.2 inch copper model at freq. = 2.45 GHz, BW = 0.025 * freq.58 mm dipole antenna, 1/4 wavelength from the inside face of the small end, centered and lying along a y diameter.Good. _________Can you give me the deltaT, Finite Difference Time Step in Meep units that you used in your present csv files?I need it to plot the Poynting fluctuation and to verify the frequency.Thanks
Quote from: Rodal on 07/06/2015 10:16 pmQuote from: aero on 07/06/2015 10:13 pm...I have re-meshed, does 245x261x261 sound good?I'll run the 10.2 inch copper model at freq. = 2.45 GHz, BW = 0.025 * freq.58 mm dipole antenna, 1/4 wavelength from the inside face of the small end, centered and lying along a y diameter.Good. _________Can you give me the deltaT, Finite Difference Time Step in Meep units that you used in your present csv files?I need it to plot the Poynting fluctuation and to verify the frequency.ThanksI'm not sure I understand your question. I don't have anything to do with the delta t, just the resolution =250. Meep does output the total number X of time step at the end of the run but I've never recorded them. I'm not sure what it means - I run 32 cycles at resolution 250 which runs for X meep time steps. I guess the total meep time 32* T_meep, could be output, (I think it is, in fact) then divided by the total time steps to get a delta t. Is that what you want? If so, you can have it from my next run. It should be the same for all runs of 32 cycles at 2.45 GHz.
Quote from: Rodal on 07/06/2015 11:08 pm...Is there one question in particular you would like me to ask? Not sure if I would be able to ask all of them or even more than one. -I
Quote from: DrBagelBites on 07/06/2015 10:45 pmI thought I would chime in with questions for the AIAA conference. I am going to be attending the event, so I will be able to report back to you guys about what happens, other questions that were asked, etc. Let me know of a couple of definite questions that anyone would want me to ask during the Q and A, and I'll be sure to ask them and report back the answers. -IJust me (maybe), but i'd like to know if any entity would like to declare that they had tested a version of an electromagnetic, propellantless engine, got null results and gave up on it. Boeing's "we're not working on it" needs a followup "why not?" to avoid ambiguity. Also, entities can be coy...believing emdrive could be construed by them to be an experiment with a shawyer replication. If I know the biz, they'll come up with a tweak and call it something else. Iow, if you say emdrive, you might get back an honest "no" simply due to a dimensional difference.Thanks for attending...wish I could.p.s. back from D.C. and able to dig into NSF-1701 again...Edit - this question would be for any session or opportunity to chat with key players...not just the 5:30 one...
Quote from: WarpTech on 07/06/2015 10:20 pm...Also, did Dr. Tajmar treat his EM Drive as a thruster or a ratchet? According to SPR and TheTraveler, if he was expecting it to thrust, he probably got Null results as is to be expected, since it is not intended to thrust without some outside influence to make it ratchet.ToddWell, I understand that Tajmar will not present his results under vacuum as "null results" but as valid results.As to the outside influence to motivate the EM Drive, how did Yang motivate her EM Drive to thrust?and more generally, can you think of a question we could ask Tajmar along these lines? (I have tried to construct such a question and it is difficult to do in a few words, without appearing unintelligible, as first one has to describe what one means by "as a ratchet under outside influence". I have enough trouble understanding what Shawyer may mean by that, much less how to construct such a question in an intelligible manner)It would be great if you and others could think of how to ask such a question to Tajmar, with a minimum of words and in a way that he understands what the question is about.
That is one thing I am going to definitely try and avoid: "EmDrive". It is a controversial name, and referring to it by a more generic "electromagnetic, propelantless engine" might incite more of a response. I'll let you know what each company says based off of the question!I'll probably ask those questions during the time of visiting booths, or if I am lucky enough, to sit next to a key player during the luncheons. I am very excited.