Author Topic: EM Drive Developments - related to space flight applications - Thread 3  (Read 1881375 times)

Offline Dortex

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You say there is little test data...
I say there is NONE past EW.
To this point we have EW...
Shaywer and the Chinese are mistaken. This is what Occam says and after much ado appears to be correct.
I see the hint from old timers here that I may be correct.

Dismissing data is easy. Refutation takes work.

Have lost hope.
IMHO what was promising has turned into dust.

Why do you say that? (What have I missed?)

Offline FutureStormtrooper

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Time and further experiments will tell. Frankly, our personal feelings about this mean bugger all in the short run, as others are going to keep running experiments whether we like it or not.

Shawyer will be presenting this year, EW will have new experimental data this year. Those are the big reveals I'm looking forward to, and to my mind, will say how to gauge my hope going forward.

Offline ThinkerX

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Quote
Have lost hope.
IMHO what was promising has turned into dust.

I have been going back and forth on this for almost a year now...and I cannot agree.

As pointed out, we are still awaiting EW's results.

Shawyer, for all his theory issues, has a great deal of 'hands on' experience with these devices, which give at least the appearance of producing thrust.  Replication is the key here.  Identical items in different labs producing or not producing identical amounts of thrust under identical conditions.  This hasn't happened yet.  Same for the Chinese versions. 

Theory wise, to me, it looks like at least some of the more disparate theories of operation are starting to converge.  Warp-Tech has mentioned Doctor McCulloch's theory more than once.  McCulloch, for his part, is starting to contemplate interaction of some sort with the Zero Point Field, which is what Doctor White's theory is centered on.  And Notsosureofits theory seems similar (?) compatible (?) with Warp-Tech's and maybe others.

Offline Flyby

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Have lost hope.
IMHO what was promising has turned into dust.

I think you rather lost patience then hope...hence the need to vent your frustration. :)

It is true there is not enough real experimental evidence. I agree with you on that.

But all the test done so far do provide "indication of proof" that something is might be happening we have not yet understood very well.
We're all eagerly waiting for that one specific test that provides "pure evidence" and not just an "indication"....

That the baby EMdrive wouldn't yield any noticeable result was not a surprise to me. I had my doubts from the start : too small (hence too dimensional sensitive) and not enough power.

If I were you, i'd try to stay away of the conspiracy theories regarding Iulian's lack of activities. It is not uncommon for an active engineer to move around the world...

We still have 4 tests on the shelf to look out for : Eagleworks, TheTraveler's (when he gets better), rfmwguy(in the works) and our hot-tubbing Seeshell (planning stage)  ;D


Then there is also a promised announcement/peer review from Shawyer, now his EMdrive got the spotlights thanks to press-hysteria about EW test and the article published here on the nasaspaceflight forums. I can only hope it is loaded with data on his supercooled EMdrive experiment..but i kinda fear it will be disappointing...we'll see..

patience, my dear Watson.. patience...
« Last Edit: 06/21/2015 07:29 AM by Flyby »

Offline Star One

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Time and further experiments will tell. Frankly, our personal feelings about this mean bugger all in the short run, as others are going to keep running experiments whether we like it or not.

Shawyer will be presenting this year, EW will have new experimental data this year. Those are the big reveals I'm looking forward to, and to my mind, will say how to gauge my hope going forward.

Hopefully things maybe clearer one way or the other by September/October, as have a feeling we should hear more from both EW & Shawyer by then.

Would be helpful if people stayed away from any expectations either way on any of these experiments and their results.
« Last Edit: 06/21/2015 07:52 AM by Star One »

Offline rfmwguy

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Simple mechanical fulcrum built and settling in on balance as I type. Will upload video in a little while.

Offline Rodal

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Simple mechanical fulcrum built and settling in on balance as I type. Will upload video in a little while.
It's great to have you "live" here to comment on your built.

One thing that previous researchers have not commented on is the geometrical tolerances of their tested EM Drives.  Would you be able to give us some assessment of the circular runout and concentricity of your truncated cone?  And what is the accuracy of your measurements (are you using a caliper, for example?)

The reason I'm asking is because calculations of frequency and mode shapes are dependent on actual internal geometrical dimensions.  NASA's truncated cone was built in a researcher's living room, therefore it is my assessment that one cannot seek too much precision, perhaps not more that 1%, perhaps less.

I also wonder about the stability of the geometrical dimensions, as the coper sheets used are very thin, hence the geometry can change with time as the EM Drives are stressed under handling and thermal stresses.
« Last Edit: 06/21/2015 03:17 PM by Rodal »

Offline Rodal

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Its a Time-Marching solution. The image shows the center slice of computational lattice at the end of the run, 16 peroids of the drive frequency, (2.45 GHz). The outer boundary of the .jpg image is the outer boundary of the computational lattice, or mesh, which is a cuboid. You can see the frustum boundaries within the mesh. The color represents the energy at that point within the mesh. It looks like there is color outside the frustum boundaries. I will make more runs and attempt to get some color discrimination within the frustum.

Can you show a plot of something (for example max amplitude, or amplitude at a given location) vs. time to assess the time variation and the progress from transient to steady-state?

Also to see whether the variation is harmonic with time or not...

Offline aero

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Its a Time-Marching solution. The image shows the center slice of computational lattice at the end of the run, 16 peroids of the drive frequency, (2.45 GHz). The outer boundary of the .jpg image is the outer boundary of the computational lattice, or mesh, which is a cuboid. You can see the frustum boundaries within the mesh. The color represents the energy at that point within the mesh. It looks like there is color outside the frustum boundaries. I will make more runs and attempt to get some color discrimination within the frustum.

Can you show a plot of something (for example max amplitude, or amplitude at a given location) vs. time to assess the time variation and the progress from transient to steady-state?

Also to see whether the variation is harmonic with time or not...

I've attached some images. This run was 2-D so the images are, well, from a 2-D run + time, not 3-D. I went back to 2-D runs to to save time while exploring general area. These images use the "lines" color map and were snapped at 5.8, 6 and 6.2 Periods into the run so they are what, about 70 degrees apart? I think you can see much of my difficulty. How do I get the information we want or need from the data at hand?

I don't mind taking the time to make long, 3-D runs, but information extraction is another skill that is needed.

As for generating the plots you asked for, I think, I'm not sure but I think that is a MATLAB task, or Octave of course, and hence new code of a different kind. I'll happily provide the data files via Google Drive, just tell me what model you'd like run. We know the most about the EW models, but Yang claimed the largest F/P, hence that may be the choice.
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Offline Rodal

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Its a Time-Marching solution. The image shows the center slice of computational lattice at the end of the run, 16 peroids of the drive frequency, (2.45 GHz). The outer boundary of the .jpg image is the outer boundary of the computational lattice, or mesh, which is a cuboid. You can see the frustum boundaries within the mesh. The color represents the energy at that point within the mesh. It looks like there is color outside the frustum boundaries. I will make more runs and attempt to get some color discrimination within the frustum.

Can you show a plot of something (for example max amplitude, or amplitude at a given location) vs. time to assess the time variation and the progress from transient to steady-state?

Also to see whether the variation is harmonic with time or not...

I've attached some images. This run was 2-D so the images are, well, from a 2-D run + time, not 3-D. I went back to 2-D runs to to save time while exploring general area. These images use the "lines" color map and were snapped at 5.8, 6 and 6.2 Periods into the run so they are what, about 70 degrees apart? I think you can see much of my difficulty. How do I get the information we want or need from the data at hand?

I don't mind taking the time to make long, 3-D runs, but information extraction is another skill that is needed.

As for generating the plots you asked for, I think, I'm not sure but I think that is a MATLAB task, or Octave of course, and hence new code of a different kind. I'll happily provide the data files via Google Drive, just tell me what model you'd like run. We know the most about the EW models, but Yang claimed the largest F/P, hence that may be the choice.

This is very interesting as it shows p=4 instead of p=3.  What geometry is this for? Is it for the Flight Thruster geometry or for the Yang geometry?

Boundary Layer adaptation of the natural spherical standing wave to the flat ends occurs most noticeably at the Big End.



Can you show images for the end of your time marching solution (16 periods)?
« Last Edit: 06/21/2015 04:29 PM by Rodal »

Offline aero

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I'm re-running it now, just to reset my focus.

It is the Yang model, dimensions exactly as posted.

I'll post some more images once the run completes and they are generated.
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Offline zen-in

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What solid data did Julien garner? None.
Where is he now?
I disagree (agree?) we need more controlled experimental results, not more theory.

Julian Berca on fb...new job in china. I also agree more experimental data needed. Was skeptical of julians data until downward momentum measured. Upwards could have been ballooning, downward is something very different. Did not appear to be falsified. May not have had lab standard accuracies...think relative accuracy shows something. What exactly...am not sure, so my curiosity remains.

My theory on his downward thrust experiment is the reaction was caused by electromagnetic interaction of the supply wires.    The same effect would have been seen with his upward thrust experiment except bouyancy effects dominated.   Videos always look more impressive than witnessing the actual experiment firsthand.   It's possible Julian Berca has realized, after performing several experiments, that there is nothing to the em-drive.   After all he seems to be smart and honest.
« Last Edit: 06/21/2015 05:00 PM by zen-in »

Offline aero

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I'm re-running it now, just to reset my focus.

It is the Yang model, dimensions exactly as posted.

I'll post some more images once the run completes and they are generated.

Here are some images from the end of the run.

I have uploaded the complete set of images to my Google Drive but am unsure how to share them without a colaborator's email address. PM me with your email address if you'd like to look at the complete set.

I did not upload the source data file as it is 1.37 GB and so takes time even with my relatively fast cable internet connection. (Relatively fast when the cable's not dropping out, that is.)

My output is a .png every 0.2 periods of the drive frequency with the first file labled hy.t00.png output at time 0.2 periods. The color intensity is set by each file individually, rather than normalized over the data set. When normalized over the complete data set, only the last few files show any discrimination. That is, everything seems to wash out.

Quote
This is very interesting as it shows p=4 instead of p=3.  What geometry is this for? Is it for the Flight Thruster geometry or for the Yang geometry?
It could be due to antenna orientation. And I'm exciting the cavity with a magnetic component. Should I rotate the antenna and excite the electric modes?
« Last Edit: 06/21/2015 05:49 PM by aero »
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Offline Blaine

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What solid data did Julien garner? None.
Where is he now?
I disagree (agree?) we need more controlled experimental results, not more theory.

Julian Berca on fb...new job in china. I also agree more experimental data needed. Was skeptical of julians data until downward momentum measured. Upwards could have been ballooning, downward is something very different. Did not appear to be falsified. May not have had lab standard accuracies...think relative accuracy shows something. What exactly...am not sure, so my curiosity remains.

My theory on his downward thrust experiment is the reaction was caused by electromagnetic interaction of the supply wires.    The same effect would have been seen with his upward thrust experiment except bouyancy effects dominated.   Videos always look more impressive than witnessing the actual experiment firsthand.   It's possible Julian Berca has realized, after performing several experiments, that there is nothing to the em-drive.   After all he seems to be smart and honest.

electromagnetic interaction of the supply wires? I wasn't aware copper was that magnetic.  I mean, unless I don't understand what you are saying.  Interaction with what?
Weird Science!

Offline Rodal

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I'm re-running it now, just to reset my focus.

It is the Yang model, dimensions exactly as posted.

I'll post some more images once the run completes and they are generated.

Here are some images from the end of the run.

I have uploaded the complete set of images to my Google Drive but am unsure how to share them without a colaborator's email address. PM me with your email address if you'd like to look at the complete set.

I did not upload the source data file as it is 1.37 GB and so takes time even with my relatively fast cable internet connection. (Relatively fast when the cable's not dropping out, that is.)

My output is a .png every 0.2 periods of the drive frequency with the first file labled hy.t00.png output at time 0.2 periods. The color intensity is set by each file individually, rather than normalized over the data set. When normalized over the complete data set, only the last few files show any discrimination. That is, everything seems to wash out.

Quote
This is very interesting as it shows p=4 instead of p=3.  What geometry is this for? Is it for the Flight Thruster geometry or for the Yang geometry?
It could be due to antenna orientation. And I'm exciting the cavity with a magnetic component. Should I rotate the antenna and excite the electric modes?
p=4 makes sense for some of the TM modes.

Definitely.

Could could you please rotate the antenna and excite the electric modes?

Offline rfmwguy

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As promised, here is my video of the first test of my mechanical fulcrum. It will be used to show relative weight change in addition to a digital scale. Had some concerns about the digital scale alone, possibly being affected by the RF. The fulcrum is simply designed to be an alternate test method.


Offline aero

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Ok - I've rotated the antenna and am running electric mode excitation now. Be a few minutes.

I note that Harminv detected 3 resonant frequencies for this cavity, 2.23495377E+009, 2.48317048E+009 and 2.67105206E+009 Hz for this cavity when run in this configuration but at much lower resolution. Q's all about the same 1000 < Q < 1500.
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Offline Rodal

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Ok - I've rotated the antenna and am running electric mode excitation now. Be a few minutes.

I note that Harminv detected 3 resonant frequencies for this cavity, 2.23495377E+009, 2.48317048E+009 and 2.67105206E+009 Hz for this cavity when run in this configuration but at much lower resolution. Q's all about the same 1000 < Q < 1500.

Yang also reported that his Q was about 1500, so that's pretty good, much better than the millions you were getting before !
« Last Edit: 06/21/2015 07:11 PM by Rodal »

Offline Rodal

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As promised, here is my video of the first test of my mechanical fulcrum. It will be used to show relative weight change in addition to a digital scale. Had some concerns about the digital scale alone, possibly being affected by the RF. The fulcrum is simply designed to be an alternate test method.
...

Thank you for posting this !

Great work.

1) I don't know whether it is parallax due to the camera (I would like your feedback) but I saw bending of the wooden beam.  Is the wooden beam compliant enought that the two water bottles are producing visible bending of the beam simply-supported by the knife edge?  If so, you may have two sources of oscillation:

a) lowest frequency oscillation: rigid body rotation of the beam around the knife edge
b) higher frequency oscillation: beam bending oscillations (there are an infinite number, but unless it was parallax I clearly saw beam bending : the first mode)

Couldn't see whether the oscillations were due mainly to rigid body rotation or to bending, but based on the very long period of oscillation, it must be mainly due to rigid body rotation of the beam.

2) If you cannot wait for the oscillations to dampen (>30 minutes ?) in the future, you may have to also include (oil or water) damping.
« Last Edit: 06/21/2015 07:29 PM by Rodal »

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