Author Topic: EM Drive Developments - related to space flight applications - Thread 3  (Read 1803945 times)

Offline SeeShells

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...

The JNaudin website has many variants of Byfield-Brown effect lifters.  I remember seeing balsa wood electrostatically driven hoverers in Popular Science in the early 60's. 

...

There is no relationship to an em-drive cavity except both are empty metal shells and neither one creates momentum out of thin air.
Thanks. curious, are u 100% certain, beyond any reasonable doubt, that an "empty shell" can never gain momentum and that propulsion must utilize propellants?
Propulsion does not always require propellants.   For example deep space satellites are often swung around a planets to add delta v.  However there is no machine that will by itself create momentum.  The em-drive will eventually take its place next to cold fusion, polywater, and 300 MPH submarines in the Encyclopedia of Pseudoscience.
Gravity assist is not technically propulsion nor is dropping a rock. although you did not answer directly, you apparently are on record believing that space propulsion requires propellants. No problem, that is a safe belief system many have from the sidelines. Me? I'm not so sure we're as omnipotent as we may think we are. Otherwise, why bother with imagination and experimentation...everything has been discovered worthy of discovery.
A story...
Once upon a time there were no laws, no CoM no CoE no Maxwell and spacetime ruled. The laws melted out from the primordial soup of quarks and heat and one force after another assembled to define how our universe could work. To me it was like a can of different sized rocks and sand, when cooling down the universe shook the can and the sand and rocks self assembled.
It doesn't bother me one iota that we're shaking the can of rocks to see what happens and who knows what we will find? This isn't about saying we are going to violate anything, it's saying we are going to inquire and look and do some questioning science.

Shell

Offline SeeShells

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@SeeShells

Yes, I can add as many sources as I want. But someone else must tell me what and where. And will that help the experimenters or theorists? I wonder if the experimenters here will be able to do add many different sources. Just the problem of coming up with the equipment and materials applied in such a way as to avoid degrading the measurements.

And what is the noise bandwidth of a magnetron?

Aero,

These are the calculated TM and TE modes from NASA.  Try a couple TM modes, be a good first start to see if it can produce a viable sequence. Double check me Jose if you would like something else... no problem.

TM 311 2.4157 Ghz
TM 212 2.45032 Ghz

Shell
That's a thought. However, I thought that next I might try to generate some numbers from the cavity to get a handle on the field strength and distribution. That should provide some immediately useful data. Not immediate data, but data that will be useful as soon as it arrives.
It's good to have baseline data and I'm sure it will come into play later. So when you can add an ingredient to the soup one at a time.

Me I'm back to doing numbers on the helical cone shaped antenna and trying to get it to work well without a ground plane and fit into the cavity where I want it to.

Offline cej

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Here is attached a toy model for a kind of (uncontroversial) mechanical ratchet, ballast in a box, perfect slip in a direction, perfect stop the other way (idealised)

(...)

So an apparent "inertial ratchet" is an easily satisfiable claim, the question is the possibility of such a device that could work for long "unlimited" total displacement, to me this appears more like a problem of conservation of centre of mass than of available energy (unless energy directly beamed to vacuum to get net momentum => photon rocket again). A note of caution : it is easy to get apparent net non zero results from transients or "one shot" effects, that doesn't imply possibility for any long term stationary mode of operation.

I like your analogy -- I was not aware of it. But preserving the center of mass is essentially the same argument as conservation of momentum, which seems to rule out the possibility of any propellant-less thruster that can accelerate faster than a photon rocket. That should raise a lot of doubt. Yet here we are.

Anyhow, I think the answer to how extracting work from vibrations can satisfy conservation of momentum comes down this: there is only so much energy a spaceship can store in vibrations (or to create vibrations), that energy has an effective (finite) mass, and an inertial ratchet probably cannot extract work from that energy any faster than simply expelling it as light.

But what about the idea of an inertial ratchet hovering against gravity? If it could only hover, that would still be very useful and would lead to much more efficient space travel. Since no work is performed by hovering, how would conservation of momentum be violated?

Your mechanical inertial ratchet cannot hover because acceleration will apply evenly to its entire mass. Will the same happen for an inertial ratchet that stores angular momentum in an EM field? (Will the field accelerate along with the mass of the ratchet, or will they push against each other, causing conservation of momentum issues that requires holding the ratchet in place?)

Okay! Let us now assume that the EM Drive is an inertial ratchet, and a pretty good one! It will still extract work from vibrations, but let's assume that it cannot extract that work any faster than a photon rocket. And we'll also assume that inertial ratchets cannot actually hover (or even significantly resist gravity)... Could the "more efficient than a photon rocket" results that we've been seeing in experiments so far instead be an artifact of the unique way in which inertial ratchets respond to vibrations?


In summary, I've counter-raised the following questions for everyone to consider:
1. Can work be extracted from vibrations faster that expelling the equivalent energy as light?
2. Is it plausible for an EM field based inertial ratchet to hover against gravity? (will there be resistance between the EM field and the accelerating mass of the frustum?)

I didn't get to this point, but I'm also curious about:
3. Can an inertial ratchet extract work from QV fluctuations?

If the answer to 1, 2, & 3 are "no"...
4. Are the positive experimental results just an artifact of the inertial ratchet effect?
5. ... Can we at least use an inertial ratchet in the International Space Station as a more efficient, all-in-one air conditioner and orbit corrector?

I hope this post has at least reduced the surface area of the "inertial ratchet = space travel" hypothesis.

Offline deltaMass

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The inertial ratchet route demands that one specifies that thing off of which one pushes. What is it? Why has it not been detected as pushed off of in the other trillions of large and small, uninstrumented to fully instrumented tests of classical mechanics over the centuries? I don't expect a coherent answer, so treat this question as rhetorical and merely as food for thought. Or as a clue.

Offline arc

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The following Wave form images might help?, when thinking of the meaning of image colors/densities from meep/comsol etc. There is a relation between wave amplitude/location and the color displayed...each package will have its own definitions for color combinations... it seems that some packages use the same color scheme, but reverse definitions between positive and negative amplitudes, What was the bottom is now the top...this may explain the color switching with meep etc as waves cycle/pivot around a "defined" starting point or zero line within the cavity, or if there exist both positive and negative values in a graph the effective range may adjust to start from the middle ...we need the numeric output tables to enable further examination...still thinking on this...


--
Image 1 looking down from the top

--

--
Image 2 looking down from the top

--
« Last Edit: 07/01/2015 09:13 PM by arc »

Offline deuteragenie

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Been following this thread for a few weeks, decided to hop in to help if I could.

Aero, do you need only the most recent MEEP package?
I was going to go ahead and compile it from source for you but I found:
http://ab-initio.mit.edu/wiki/index.php/Meep_Download

According to the wiki, they have a precompiled source package available:
"apt-get install meep h5utils"

There is also a parallel source file:
"apt-get install meep-mpi"

If you need other packages compiled with it or the OpenMPI version, I will see what I can do.

I saw that one as well and was going to try it out.
If you want to help, you could try to create a Ubuntu package for Meep as aero uses Ubuntu (and so am I and a few others).  http://packaging.ubuntu.com/html/

I also do not know which compiler / optimization the source code would support, but you may want to explore recompiling the source using different compilers (gcc / LLVM / ICC / VC ...) and different optimization flags.  It can also be that the source code could enjoy being made more compiler agnostic.
« Last Edit: 06/30/2015 08:01 AM by deuteragenie »

Offline deuteragenie

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Guys

I would like to humbly submit for consideration that the efforts in this thread could in effect be viewed as a distributed research project. We have resilient experimenters, brilliant theorists, persistent data analysts.. even some equipment. However, this day in age, there are many other resources potentially available for the community to use - if only we become organized enough to identify and seek them out.

What other resources are needed to move forward the collective work taking place here?

For example, do we need:
- More MEEP analysts, to lessen the load on our brave Aero?
- AmazonAWS/Google Cloud compute time?
- A recurring schedule of group Google Hangouts to discuss current theory and next steps?
- A machine learning/data science expert, to find hidden or subtle relationships?
- Funding/donations for equipment? Perhaps held in a multisig crypto wallet with a major provider?
- A better platform for distributed research projects?
- Simply more hobbyists paying attention and contributing views?
- Perhaps we don't need anything, and this is the most efficient that we can be?

It seems we are all driving towards the same goal.. just some thoughts to consider to take this exploration one efficient step further. Happy to help however possible.

I like it, and I certainly like the first bullet. Not so sure about the brave part but the "lessen the load" part sure would help if we could somehow divide the load into parts that could be more responsive to valid and doable requests for data.

For Meep and computational resources: it should be possible to run Meep in a distributed way, relying on the BOINC infrastructure.  Meep is MPI enabled so it has the essential building block.  See here: https://boinc.berkeley.edu/trac/wiki/MpiApps
Making it work in practice is another thing altogether... A nice bachelor end work.

As regards to the analysis, it would be good to have people from the Meep community contributing to /reviewing the models.

It would also be good to try out different approaches than Meep.  For example have a look here: http://www.falstad.com/mathphysics.html. The results there are based on QM atomic orbitals, as shown here: http://daugerresearch.com/orbitals/index.shtml

So yes, they are zillions of things to do.

Offline deuteragenie

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...
Ack.

For a start, it would be good to simulate the effect of changing the dimensions a bit.  Does it dramatically affect the results ?
Same for frequency: does a small change in freq affects the results in sigificant way?
Same for antenna length.
Etc.
This could provide valuable information for experimenters.
Agreed.  Ack. There is a lot to simulate.

We are going to have to put some priorities though...(There is also the issues of antenna type, antenna location, waveguide coupling, and on and on) :)

If aero would be willing to share its latest .ctl and indicate what to change to perform sensitivity analysis, it would allow non-physicists to use their computer time and off-load the brave aero from this task.  I think we now have 2-3 persons in the audience with Meep up and running.

Offline Adaptation

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Why not build one from aluminum foil.  I'm thinking of some setup where the microwave feed is floating and not physically attached.  Turn it on and see the aluminum cone dancing around.

Offline deuteragenie

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The following Wave form images might help?...

A 3D movie with transparency would probably be nice. 
See here for example: http://machinedesign.com/archive/fast-solvers-complex-problems

The HDF5 files generated by Meep contain all data you need... problem is to extract it !

Offline Rodal

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The following Wave form images might help?, when thinking of the meaning of image colors/densities from meep/comsol etc. There is a relation between wave amplitude/location and the color displayed...each package will have its own definitions for color combinations... it seems that some packages use the same color scheme, but reverse definitions between positive and negative amplitudes, What was the bottom is now the top and vise-a-versa...this may explain the color switching with meep etc as waves cycle/pivot around a "defined" starting point or zero line within the cavity, or if there exist both positive and negative values in a graph the effective range may adjust to start from the middle ...still thinking on this......

The HDF5 files generated by Meep contain all data you need... problem is to extract it !

...That's a thought. However, I thought that next I might try to generate some numbers from the cavity to get a handle on the field strength and distribution. That should provide some immediately useful data. Not immediate data, but data that will be useful as soon as it arrives.

A) At the moment we are not even getting NUMBERS from the Meep runs, so:

1) We don't even know whether the field's magnitude are essentially zero (Meep's FD scheme does NOT satisfy Maxwell's equations throughout the meshed surface, therefore what should be zero is displayed as a contour of non-zero numbers.  In that case what is displayed is meaningless, just numerical noise that confuses people in thinking that a fractal pattern is real when it is just noise)

2) Therefore we can't distinguish between different field components.  Therefore it is even difficult to tell what mode shape is being excited or what is going on.

The first order of business is for Meep to output numbers, so that numbers can be associated with numbered scales for the images.

Without numbers, you won't be able to display any other images, as all images are made from numbers.

No numbers, no comprehension.  No numbers, no post-processing (no post-processing of images by others, etc).    No numbers, all you have are funky colors and difficult to decipher images output by Meep.

At the moment we are trying to make sense out of this by applying some heuristics, considering anything with fractals throughout as zero, and considering images with well-formed smooth contours to be the significant images.

If people want to help with Meep, what is needed is to know how to get Meep to output the NUMBERS associated with the electromagnetic fields, that is priority #1   

//////////////////////////

B) Once we get numbers, the next priority is to output the net Force at every Finite Difference Time step, to be able to plot Force vs. time, for a well-understood case.  For example, for the geometry of rfmwguy with L=9 inches that showed mode shape TM212 at 2.45 GHz which agrees with NASA's COMSOL FEA and agrees with the exact solution results.
« Last Edit: 06/30/2015 12:45 PM by Rodal »

Offline Rodal

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..
Propulsion does not always require propellants.   For example deep space satellites are often swung around a planets to add delta v.  However there is no machine that will by itself create momentum.  The em-drive will eventually take its place next to cold fusion, polywater, and 300 MPH submarines in the Encyclopedia of Pseudoscience.

The inertial ratchet route demands that one specifies that thing off of which one pushes. What is it? Why has it not been detected as pushed off of in the other trillions of large and small, uninstrumented to fully instrumented tests of classical mechanics over the centuries? I don't expect a coherent answer, so treat this question as rhetorical and merely as food for thought. Or as a clue.

For example, one can have a road with friction act as the ratchet medium.  The problem is that, according to experimental evidence, the Universe has no aether and no such road.  The experiment by Trouton and Noble has shown this to be the case more than 110 years ago, and the experiments conducted from then up to now have verified that there is no background that one can use to push on, to ratchet on, or to pull from:

https://en.wikipedia.org/wiki/Trouton%E2%80%93Noble_experiment

also the Michelson Gale Pearson experiment:

https://en.wikipedia.org/wiki/Michelson%E2%80%93Gale%E2%80%93Pearson_experiment

Propellant less forms of space travel we know we can use are:

1) Solar radiation (Solar sails),
2) gravity (Gravity assist or slingshot) , 
3) electromagnetic fields (Electric Sails, Electrodynamic Tethers),
4) momentum exchange (momentum exchange tethers and tethered formation flying) and
5) Photonic Laser Thrusters (that amplify photon thrust by repetitively bouncing photons between two highly reflective laser mirrors installed on two separate spacecraft platforms in a laser-like arrangement.)

(*) I don't list aerocapture here because aerocapture needs an atmosphere, and hence to me it does not accurately belong in "Space Propulsion" if by Space Travel we mean travel outside an atmosphere.
« Last Edit: 06/30/2015 02:22 PM by Rodal »

Offline rfmwguy

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...

...

There is no relationship to an em-drive cavity except both are empty metal shells and neither one creates momentum out of thin air.
Thanks. curious, are u 100% certain, beyond any reasonable doubt, that an "empty shell" can never gain momentum and that propulsion must utilize propellants?
...
The em-drive will eventually take its place next to cold fusion, polywater, and 300 MPH submarines in the Encyclopedia of Pseudoscience.
...
A story...
Once upon a time there were no laws, no CoM no CoE no Maxwell and spacetime ruled. The laws melted out from the primordial soup of quarks and heat and one force after another assembled to define how our universe could work. To me it was like a can of different sized rocks and sand, when cooling down the universe shook the can and the sand and rocks self assembled.
It doesn't bother me one iota that we're shaking the can of rocks to see what happens and who knows what we will find? This isn't about saying we are going to violate anything, it's saying we are going to inquire and look and do some questioning science.

Shell
Perhaps those with a negative viewpoint should submit a formal refutation paper in 2016 to the the Joint Army Navy Nasa Airforce org about the folly of Propellantless Propulsion. We're a small group of independents here, these are the big boys: https://www.jannaf.org/mtgs/June2015/pages/sps.html

"Mission Area IV: Propellantless Propulsion Systems

Chair:
Mr. Matthew Gasch, NASA-ARC/Moffett Field
Telephone:   (650) 604-5377
Email:         matthew.j.gasch@nasa.gov

Emphasis is on solar sail propulsion, electrodynamic and momentum exchange tether propulsion, aerocapture and other innovative technologies that use the natural environments of space to derive propulsion without the expenditure of conventional fuel. Atmospheric entry and thermal protection systems are also of interest.
Review or summary of previous flight experiments
Planned and/or funded missions
Near-term mission concepts
Advanced mission concepts
Innovative system or subsystem designs
Guidance, navigation and control
Space environmental effects
Atmospheric entry systems
Development, characterization, modeling and testing of TPS materials"

Offline Rodal

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[...
Perhaps those with a negative viewpoint should submit a formal refutation paper in 2016 to the the Joint Army Navy Nasa Airforce org about the folly of Propellantless Propulsion. We're a small group of independents here, these are the big boys: https://www.jannaf.org/mtgs/June2015/pages/sps.html

"Mission Area IV: Propellantless Propulsion Systems

Chair:
Mr. Matthew Gasch, NASA-ARC/Moffett Field
Telephone:   (650) 604-5377
Email:         matthew.j.gasch@nasa.gov

Emphasis is on solar sail propulsion, electrodynamic and momentum exchange tether propulsion, aerocapture and other innovative technologies that use the natural environments of space to derive propulsion without the expenditure of conventional fuel. ...

If one takes a gander at my message :  http://forum.nasaspaceflight.com/index.php?topic=37642.msg1397880#msg1397880

one will see that what the Joint Army Navy Nasa Airforce  understands as Propellant-Less Propulsion, namely:

solar sail propulsion, electrodynamic and momentum exchange tether propulsion, aerocapture

is precisely what I had carefully pointed out and enumerated, therefore there is no need to submit a  formal refutation paper to the Joint Army Navy Nasa Airforce org, as they understand what is meant by propellant propulsion in scientific/engineering terms. 

Everything that the Joint Army Navy Nasa Airforce lists as Propellant Less propulsion respects the known laws of Physics: including both Conservation of Momentum and Conservation of Energy.

The EM Drive (although it has been "around" in some form since 1988's Shawyer's patent application) is not in that list because:

1) The EM Drive experimental results are all over the place with a huge statistical spread (Force/Power Multiple of Photon Rocket ranging from 84 times to 320,000 times)

2) The "explanations" given for its operation (starting with Shawer's) have been met with disapproval by the scientific community.  The assumption (used to support extravagant claims for space travel) that it can provide constant force/PowerInput leads to a free-energy machine: this is particularly disturbing to anybody in the scientific/engineering community.

IMHO if the EM Drive is to make it into that list, experimental results will have to be scientifically verified at academic and research institutions and the mode of operation will have to be understood in accord with the same physical laws that govern the rest of the Universe.
« Last Edit: 06/30/2015 12:47 PM by Rodal »

Offline deuteragenie

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The following Wave form images might help?, when thinking of the meaning of image colors/densities from meep/comsol etc. There is a relation between wave amplitude/location and the color displayed...each package will have its own definitions for color combinations... it seems that some packages use the same color scheme, but reverse definitions between positive and negative amplitudes, What was the bottom is now the top and vise-a-versa...this may explain the color switching with meep etc as waves cycle/pivot around a "defined" starting point or zero line within the cavity, or if there exist both positive and negative values in a graph the effective range may adjust to start from the middle ...still thinking on this......

The HDF5 files generated by Meep contain all data you need... problem is to extract it !

...That's a thought. However, I thought that next I might try to generate some numbers from the cavity to get a handle on the field strength and distribution. That should provide some immediately useful data. Not immediate data, but data that will be useful as soon as it arrives.

A) At the moment we are not even getting NUMBERS from the Meep runs, so:

1) We don't even know whether the field's magnitude are essentially zero (Meep's FD scheme does NOT satisfy Maxwell's equations throughout the meshed surface, therefore what should be zero is displayed as a contour of non-zero numbers.  In that case what is displayed is meaningless, just numerical noise that confuses people in thinking that a fractal pattern is real when it is just noise)

2) Therefore we can't distinguish between different field components.  Therefore it is even difficult to tell what mode shape is being excited or what is going on.

The first order of business is for Meep to output numbers, so that numbers can be associated with numbered scales for the images.

Without numbers, you won't be able to display any other images, as all images are made from numbers.

No numbers, no comprehension.  No numbers, no post-processing (no post-porcessing of images by others, etc).    No numbers, all you have are funky colors and difficult to decipher images output by Meep.

At the moment we are trying to make sense out of this by applying some heuristics, considering anything with fractals throughout as zero, and considering images with well-formed smooth contours to be the significant images.

If people want to help with Meep, what is needed is to know how to get Meep to output the NUMBERS associated with the electromagnetic fields, that is priority #1   

//////////////////////////

B) Once we get numbers, the next priority is to output the net Force at every Finite Difference Time step, to be able to plot Force vs. time, for a well-understood case.  For example, for the geometry of rfmwguy with L=9 inches that showed mode shape TM212 at 2.45 GHz which agrees with NASA's COMSOL FEA and agrees with the exact solution results.

I have already explained how to get a CSV file with the fluxes and repeat the information (example) below for convenience.  I have tested it and it works.

1. Define a region where flux is to be measured

(define wvg-pwr (add-flux f 0 1
    (make flux-region (direction Z) (center 0 0)
       (size (* 1.2 (+ (* 2 sw) s)) (* 1.2 sw) 0))))

2. Display the fluxes (the output will be as CSV), in the run-until section:

(display-fluxes wvg-pwr)

Offline Rodal

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...

I have already explained how to get a CSV file with the fluxes and repeat the information (example) below for convenience.  I have tested it and it works.

1. Define a region where flux is to be measured

(define wvg-pwr (add-flux f 0 1
    (make flux-region (direction Z) (center 0 0)
       (size (* 1.2 (+ (* 2 sw) s)) (* 1.2 sw) 0))))

2. Display the fluxes (the output will be as CSV), in the run-until section:

(display-fluxes wvg-pwr)

Thank you. 

Can you also provide instructions on how to output numbers for the electromagnetic fields (Ex, Ey, Ez, Hx, Hy, Hz) at the final time step ?

Even better, and more desirable, can you provide instructions on how to output a numerical label for the contour plots being displayed by aero, associating the contour colors to numbers, as it is done in just every other FEA and FD computer code contour displays, or as routinely done in Mathematica, Maple, etc. and other software that displays contour plots?

If the answer is no, maybe other readers of this thread, willing to hep, can help.
« Last Edit: 06/30/2015 01:04 PM by Rodal »

Offline deuteragenie

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...

I have already explained how to get a CSV file with the fluxes and repeat the information (example) below for convenience.  I have tested it and it works.

1. Define a region where flux is to be measured

(define wvg-pwr (add-flux f 0 1
    (make flux-region (direction Z) (center 0 0)
       (size (* 1.2 (+ (* 2 sw) s)) (* 1.2 sw) 0))))

2. Display the fluxes (the output will be as CSV), in the run-until section:

(display-fluxes wvg-pwr)

Thank you. 

Can you also provide instructions on how to output numbers for the electromagnetic fields (Ex, Ey, Ez, Hx, Hy, Hz) at the final time step ?

Even better, and more desirable, can you provide instructions on how to output a numerical label for the contour plots being displayed by aero, associating the contour colors to numbers, as it is done in just every other FEA and FD computer code contour displays, or as routinely done in Mathematica, Maple, etc. and other software that displays contour plots?

If the answer is no, maybe other readers of this thread, willing to hep, can help.

a. Example: (at-end output-efield-z) will store Ez in the final (ie last) HDF5 file. 

Update!

How to extract this data in a text format: http://ab-initio.mit.edu/h5utils/h5totxt-man.html

Where aero currently use h5topng to create the images, h5totxt will extract the data as csv.  It should be installed on his computer as it is part of the h5 utils tool set.  All untested, but we are not too far to get numbers.




b. Unfortunately I do not know how this can be achieved.
« Last Edit: 06/30/2015 02:09 PM by deuteragenie »

Offline Rodal

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...
How to extract this data in a text format: http://ab-initio.mit.edu/h5utils/h5totxt-man.html

Where aero currently use h5topng to create the images, h5totxt will extract the data as csv.  It should be installed on his computer as it is part of the h5 utils tool set.  All untested, but we are not too far to get numbers.[/color]



b. Unfortunately I do not know how this can be achieved.

With data extracted as a  csv (h5totxt) it would be trivial for any of us to plot the data in a more comprehensible form (than the present display by h5topng that do not show the contour numbers, hence we have no idea of what the contours represent).

I could plot it with Mathematica, for example, displaying the contour field numbers, 3D plots, movies etc.
There are so many programs available to show images out of numeric data, and to post-process the data that appear to be better than h5topng ...

Having the numeric data, we could all post-process the data ourselves to calculate the Poynting vector and other data ourselves directly from the raw numeric data of the field components.

I could plot the field at 45 degrees or any other angle to the Cartesian axis, etc. etc.

All we need is to have the numbers in a file with known format (csv is fine) so that the numbers can be interpreted as such.
« Last Edit: 06/30/2015 03:26 PM by Rodal »

Offline aero

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I have already explained how to get a CSV file with the fluxes and repeat the information (example) below for convenience.  I have tested it and it works.

1. Define a region where flux is to be measured

(define wvg-pwr (add-flux f 0 1
    (make flux-region (direction Z) (center 0 0)
       (size (* 1.2 (+ (* 2 sw) s)) (* 1.2 sw) 0))))

2. Display the fluxes (the output will be as CSV), in the run-until section:

(display-fluxes wvg-pwr)

Thank you. 

Can you also provide instructions on how to output numbers for the electromagnetic fields (Ex, Ey, Ez, Hx, Hy, Hz) at the final time step ?

Even better, and more desirable, can you provide instructions on how to output a numerical label for the contour plots being displayed by aero, associating the contour colors to numbers, as it is done in just every other FEA and FD computer code contour displays, or as routinely done in Mathematica, Maple, etc. and other software that displays contour plots?

If the answer is no, maybe other readers of this thread, willing to hep, can help.

a. Example: (at-end output-efield-z) will store Ez in the final (ie last) HDF5 file. 

Update!

How to extract this data in a text format: http://ab-initio.mit.edu/h5utils/h5totxt-man.html

Where aero currently use h5topng to create the images, h5totxt will extract the data as csv.  It should be installed on his computer as it is part of the h5 utils tool set.  All untested, but we are not too far to get numbers.




b. Unfortunately I do not know how this can be achieved.

Hey, thanks for taking the time to find that in the documentation. Using it on a 2D test file is a piece of cake. Now to use is on some real 4D data.  :)
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Offline zen-in

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...

The JNaudin website has many variants of Byfield-Brown effect lifters.  I remember seeing balsa wood electrostatically driven hoverers in Popular Science in the early 60's. 

...

There is no relationship to an em-drive cavity except both are empty metal shells and neither one creates momentum out of thin air.
Thanks. curious, are u 100% certain, beyond any reasonable doubt, that an "empty shell" can never gain momentum and that propulsion must utilize propellants?
Propulsion does not always require propellants.   For example deep space satellites are often swung around a planets to add delta v.  However there is no machine that will by itself create momentum.  The em-drive will eventually take its place next to cold fusion, polywater, and 300 MPH submarines in the Encyclopedia of Pseudoscience.
Gravity assist is not technically propulsion nor is dropping a rock. although you did not answer directly, you apparently are on record believing that space propulsion requires propellants. No problem, that is a safe belief system many have from the sidelines. Me? I'm not so sure we're as omnipotent as we may think we are. Otherwise, why bother with imagination and experimentation...everything has been discovered worthy of discovery.

Gravity assist is often cited as an example of propellantless propulsion.   It is not like dropping a rock.  The planet's gravity constrains the satellite to a hyperbolic trajectory but it is the orbital momentum of the planet that is transferred to the spacecraft, not gravitational potential energy.   The satellite is pulled to a faster trajectory by the planet.  Gravity assist is the only reactionless drive.   Electrodynamic tethers push against the Earth, using the geomagnetic field.   Solar sails reflect solar radiation, another reaction effect.

"you apparently are on record believing that space propulsion requires propellants"
I don't know where you saw that because that is not my belief.   None of the examples I just mentioned require a propellant.   And I am certain other novel methods of propellantless spacecraft propulsion will be developed.   What I don't believe in is the em-drive.   
« Last Edit: 06/30/2015 04:12 PM by zen-in »

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