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#2520 by Rodal on 17 May, 2016 14:42
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Can't comment on diamagnetism besides saying that it is a very small effect (relative permeability of copper=0.999991, which is extremely close to 1 for vacuum and air), and that at optical frequencies only the electrons should be able to respond significantly. Your Meep run only knows about copper from the properties that were input into Maxwell's equations (am I correct that this was done with a simplified Drude model for frequencies much lower than the plasma frequency ?), hence we analyze the Meep calculations from this viewpoint.QuoteIn the one big simulation I ran in meep (aero's data, seeshell's design) I found the magnetic field had a ~3x larger energy density impingement on the small end (middle of thread 6). If we follow the same line of reasoning, then thrust should be towards the small end (based on this one simulation). The small and large end plate energy graphics are attached.
Bah. I have to re-create one of the data files to get the exact numbers. It'll take 45 minutes and I don't think I can keep my eyes open that long
Here are the graphic files - I'll post the CSV summation data in the morning...
OK - the 3x number I was doing from memory and wasn't right, but the small end energy is 1.64x the big end. Attached are the CSV files from which the graphics are made. If you open them up in a spreadsheet and add up all the values (press CTRL-A and look at the summary on the bottom right in Open Office or Excel) you can see the total (all numbers are positive). I'm not going for scale here (watts/newtons/etc), just the imbalance in energy. Also note for the big end the area in the spreadsheet corresponding to the square waveguides should be excluded - it's approximately balanced by the other face of the waveguide (I proved this to myself by looking at the data) although even including it shows an imbalance favoring the small end.
Also attached is the POVRay source. I don't expect folks to understand this entirely, but the key equation is on line 112:
#declare tmp_mag_field = abs( VCos_Angle(csv_vector[row][col], z) ) * vlength(csv_vector[row][col]);
VCos_Angle returns a number that is the cosine of the angle between the 3D vector of the H field and the Z vector <0,0,1>; meaning that if the magnetic vector is normal to the plane, you get 1.0 and if it's parallel to the plane you get 0. This is then multiplied by the vector length which is the intensity of the H field at that location.
So: I know this is the correct equation for the thermal energy going into the plane at this location.
However it's also the equation for the diamagnetic energy reflected from the copper.
Yes, that reflection is small (1e-5 for copper) but there is an imbalance and the effect we see in 'anomalous thrust' is also quite small. Note also this doesn't take into account any of the data from the sloped sides.
Diamagnetism is a quantum effect (per Feynman), and so isn't accounted for by equations from Maxwell or Faraday. I don't yet entirely understand the data I'm seeing, but given the same material on both faces (copper) and the same frequency of microwaves (~2.45Ghz) throughout the cavity could this imbalance in diamagnetic reflection produce a mechanical effect? Is the frustum 'standing' or floating on the microwave energy and being shifted in one direction (toward the small end) by the diamagnetic repulsion? If this was a motor, I'd talk about it as a rotor and a stator. In this case, people would like this to be a linear motor (what's the linear motor equivalent term of 'rotor'?) So I'm thinking about this as the EM field being the rotor and everything else (the frustum and its attached spacecraft) being the stator. The EM field generates a linear magnetic impulse and the frustum shifts to compensate.
I can't speak to the general case (yet) only this one simulation result. I don't want this to degenerate into another COE/COM VIOLATION harangue. Yes, that's probably the key issue for the device, but given this one set of data can we say something about it?
One magnetics/Rf question: Is the diamagnetic effect scaled by the frequency? That is: based on the fact that the skin depth decreases with frequency, I might expect the diamagnetic effect to be proportional to the skin depth i.e. the total volume of copper generating the magnetic reflection. I can't find that anywhere, but I don't have any real Rf textbooks - 2 hours on google turned up nothing...
(edit: fixed attachments)
Regarding the calculations:
1) The forces at a given point in space are not only due to the electromagnetic fields at a given point in time (which can be calculated from the stress tensor and hence due in large part to the energy density at a given point in time) but they are also due to the derivative with respect to time of the Poynting vector. This is so because the electromagnetic fields have electromagnetic momentum, and in a time-varying field one cannot neglect its contribution. As an analogy, in a dynamic problem, as for example the vibration of a mass-spring system, the force is not only due to the spring stiffness but there is also an inertial force due to the mass acceleration (derivative of momentum with respect to time) that cannot be neglected.
2) Therefore to assess the forces acting on the EM Drive, one should not only take into account the electromagnetic fields at a given point in time but also one should take into account the force due to the derivative with respect to time of the Poynting vector.
3) Besides satisfying conservation of momentum (that relates the stress gradient to the derivative with respect to time of the Poynting vector field) one has to satisfy conservation of energy. Conservation of energy relates the time derivative of the energy density to the gradient of the Poynting vector field. So, to understand what is going on, one needs to not only look at the electromagnetic fields but also one must look at their derivatives with respect to time.
4) The Meep runs that I analyzed, had been taken to an extremely small, insignificant amount of accumulated time since the microwave injection was turned on: (orders of magnitude less than a second), and the electromagnetic fields were growing exponentially with time, thus the time derivative of the fields cannot be neglected in these Meep runs, and need to be taken into account to asses what is going on.
5) The electromagnetic fields are a function of time hence to assess their behavior one needs to see their change vs time (what is the cyclic average? since the fields are changing their sign sinusoidally). So one needs to asses the fields behavior vs time as well as the derivative with respect to time of the fields vs time, to asses what is going on.
6) Finally (I know you know this, but just to remind us) Meep is also showing a pressure on the conical side walls, in addition to the flat end plates, this has to be taken into account to figure out the total resultant force on the cavity. -
#2521 by Rodal on 17 May, 2016 16:58
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What do they do with it? The photons were generated by blowing on a ships sail...they originated within the frustum. It can't move itself. Leaves a big problem...one end of the mass has momenta information. CoM needs to balance.
How does CoM balance? Our self generating photon wind keeps the momenta information building on the large end. Momenta builds. The universe is not happy.
Extraction of momenta information from the opposite direction of the large plate to maintain CoM in the mass. It must come from the same type of source...photons...imparting momenta in an equal and opposite reaction. It becomes a sponge. Spooky action at a distance, where disconnected atomic particals change color without apparent information exchange...so with photons? Only these remote photons give up opposite momenta (if they possess it) to allow a balance on the emdrive millimeters or light years away.
So I guess what I'm unprofessionally positing is CoM is responsible for the reaction force, but we are dealing with like photon to photon interactions and not plasma, magnetic or ion effects.
OK, maybe some of you will give me a brown star for this
Although one can summarize the reason why it should move, as you did, McCulloch writes (http://physicsfromtheedge.blogspot.com/2016/05/clearer-explanation-of-mihsc-emdrive.html) that the movement still requires NEW PHYSICS (in McCulloch's case the Quantum Vacuum effect known as Unruh effect)QuoteTo conserve momentum the cavity has to move the other way towards the narrow end (note: this needs new physics, MiHsC, not standard).
Also our most distinguished NSF member, Notsosureofit arrived at a similar conclusion regarding as to why it may move (http://emdrive.wiki/@notsosureofit_Hypothesis), additionally taking into account the mode shapes. He had a nice poem about the matter -
#2522 by SeeShells on 17 May, 2016 18:08
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Just food for thought. While working on the project and waiting for my soldering iron to heat up I admit I was daydreaming what it would be like as a photon inside of a frustum. I was thinking how the actions in a asymmetrical cavity squeezing the photons modes looked like spaghettification in dropping down into a black hole. I realized how the stretching spaghettification in a drive would look just like it.
I'm thinking what other effects would this mirror? Back to soldering and daydreaming, my 2 favorite things (well, maybe a hot tub).
Shell
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#2523 by Rodal on 17 May, 2016 18:20
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Just food for thought. While working on the project and waiting for my soldering iron to heat up I admit I was daydreaming what it would be like as a photon inside of a frustum. I was thinking how the actions in a asymmetrical cavity squeezing the photons modes looked like spaghettification in dropping down into a black hole. I realized how the stretching spaghettification in a drive would look just like it.
McCulloch's view?
I'm thinking what other effects would this mirror? Back to soldering and daydreaming, my 2 favorite things (well, maybe a hot tub).
Shell
Imagine you are a string.
When you enter the cavity you (the string) are vibrating (imagine the string ripple), as you travel from the injection point to the big end (at a constant speed equal to the speed of light) the frequency of vibration increases (the wavelength of vibration decreases). As the frequency of vibration of the string increases, you (the string) acquire more energy and more momentum. As you acquire more energy and more vibration you experience the very strange Unruh effect: you experience black body radiation. The closer you get to the big end, the higher the frequency (the lower the wavelength) and the more black body radiation you experience. The closer you get to the big end the warmer that everything around you feels: the warmer the photon gas around you.
All that Blackbody Radiation (all those photons at resonant Q) towards the big end result in the EM Drive moving towards the small end to conserve momentum.
QUESTION: Shouldn't the photon gas greater temperature towards the big end of the EM Drive be something that could be measured ? (if indeed is high enough to result in the EM Drive having to accelerate towards the opposite end: the small end, to conserve momentum)? Is the measurement of Unruh temperature a check on McCulloch's theory?
(a proper acceleration of 2.5 × 1020 m·s−2 corresponds approximately to a temperature of 1 K.)
ANSWER: Probably not because the Unruh temperature is experienced by the observer (the photon) travelling at the speed of light, experiencing a change in momentum, and not by a stationary observer
The passenger in a car taking a tight turn experiences a centrifugal force, but a stationary observer sees instead the passenger trying to continue in the direction that was going, no centrifugal force, while the car is the one making the turn and restraining the passenger. Thus the centrifugal force is something experienced by the observer in its own accelerating frame of reference.
An analogy (credit: Scholarpedia Prof. Stephen A. Fulling,and Prof. George E. A. Matsas) is the appearance of inertial (centrifugal, Coriolis, etc.) forces in noninertial frames. They do not require any more confirmation than classical mechanics does, because inertial forces are necessary to allow noninertial observers to reproduce the same experimental predictions calculated by inertial ones (e.g., the trajectory of a Foucault pendulum). -
#2524 by SeeShells on 17 May, 2016 18:49
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I see what you're saying. Thanks for posting.Just food for thought. While working on the project and waiting for my soldering iron to heat up I admit I was daydreaming what it would be like as a photon inside of a frustum. I was thinking how the actions in a asymmetrical cavity squeezing the photons modes looked like spaghettification in dropping down into a black hole. I realized how the stretching spaghettification in a drive would look just like it.
McCulloch's view?
I'm thinking what other effects would this mirror? Back to soldering and daydreaming, my 2 favorite things (well, maybe a hot tub).
Shell
Imagine you are a string. When you enter the cavity you (the string) are vibrating (imagine the string ripple), as you travel from the injection point to the big end (at a constant speed equal to the speed of light) the frequency of vibration increases (the wavelength of vibration decreases). As the frequency of vibration of the string increases, you (the string) acquire more energy and more momentum. As you acquire more energy and more vibration you experience the very strange Unruh effect: you experience black body radiation. The closer you get to the big end, the higher the frequency (the lower the wavelength) and the more black body radiation you experience. The closer you get to the big end the warmer that everything around you feels: the warmer that th photon gas is.
All that Blackbody Radiation (all those photons at resonant Q) towards the big end result in the EM Drive moving towards the small end to conserve momentum.
I'm not so sure it's anyone's view as I didn't look at it that way or attach it to anyone's theory, it was just an observation. I looked at it as a black hole doesn't suck you down as much as warped spacetime pushes you into it. By squeezing and spaghettification of the mode it reacts just like it would if there was a black hole at the small end of the cavity. The photons don't know that the spaghettification they are experiencing isn't dropping into a black hole. There is no information they can share with any other part in the internal walls of the cavity because they are at light speed, but they can interact with spacetime as it permeates all space inside the frustum and outside equally.
Spacetime reacts through the closed frame of the cavity and sees it just like it was energy being stretched into a black hole. Since a black hole doesn't pull or suck you in but space pushes you. In the example I posted the Big end would be away from the direction of push.
We know photons are effected by spacetime but can photons effect spacetime and how much is the question.
Shell
Let's stretch the modes a little longer to get my point across.
Or maybe this is why this shape might do better at a frustum?
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#2525 by FattyLumpkin on 17 May, 2016 20:24
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Dr. Rodal, I was wondering if you could explain something to me: in the talk Sonny gave at Ames RC he stated "we were able to get about (x) Watts of power into the test article in this configuration". Two things: 1) when he states "configuration" Is he referring to the frequency that would excite the desired mode being test? and 2) "we were able to get"..... Was something preventing them from injecting more power into the frustum at any or some of the given frequencies and their concomitant modes?
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#2526 by Rodal on 17 May, 2016 20:29
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Dr. Rodal, I was wondering if you could explain something to me: in the talk Sonny gave at Ames RC he stated "we were able to get about (x) Watts of power into the test article in this configuration". Two things: 1) when he states "configuration" Is he referring to the frequency that would excite the desired mode being test? and 2) "we were able to get"..... Was something preventing them from injecting more power into the frustum at any or some of the given frequencies and their concomitant modes?
The amount of power that you are able to input into a cavity is related to the size of the cavity: the amplitude of the electric field will be higher in a smaller size cavity at the same input power. Higher electric field amplitude is limited by electric breakdown. Larger cavities have corresponding lower natural frequencies for the same mode shape.
I would like to hear the full context in which he says this.
Could you please post the youtube video and indicate the time on the video when he says this?
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#2527 by Monomorphic on 17 May, 2016 20:43
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Build update: I'm getting very close to being able to run some powered tests. Sorry Dr. Rodal, no self-contained batteries yet. I want to work on a way to hot-swap different frustums, and then start thinking about integrating all electronics and batteries onto the beam. It's not as simple as it sounds!
I built a laser mount for a tripod I had, where I will also mount the IR camera. The laser bounces off a first surface mirror attached to the bottom center of the pendulum beam - and hits the wall opposite approximately 30 feet away.
This system is very sensitive. I will need to wait 15 minutes or more between tests to let the pendulum go back to center (provided there is any movement at all).
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#2528 by Rodal on 17 May, 2016 20:46
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Build update: I'm getting very close to being able to run some powered tests. Sorry Dr. Rodal, no self-contained batteries yet. I want to work on a way to hot-swap different frustums, and then start thinking about integrating all electronics and batteries onto the beam. It's not as simple as it sounds!
Godspeed !
I built a laser mount for a tripod I had, where I will also mount the IR camera. The laser bounces off a first surface mirror attached to the bottom center of the pendulum beam - and hits the wall opposite approximately 30 feet away.
This system is very sensitive. I will need to wait 15 minutes or more between tests to let the pendulum go back to center (provided there is any movement at all).
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#2529 by jmossman on 17 May, 2016 20:47
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......
McCulloch's view?
I was thinking how the actions in a asymmetrical cavity squeezing the photons modes looked like spaghettification in dropping down into a black hole. I realized how the stretching spaghettification in a drive would look just like it.
...
...
All that Blackbody Radiation (all those photons at resonant Q) towards the big end result in the EM Drive moving towards the small end to conserve momentum.
I looked at it as a black hole doesn't suck you down as much as warped spacetime pushes you into it. By squeezing and spaghettification of the mode it reacts just like it would if there was a black hole at the small end of the cavity. The photons don't know that the spaghettification they are experiencing isn't dropping into a black hole. There is no information they can share with any other part in the internal walls of the cavity because they are at light speed, but they can interact with spacetime as it permeates all space inside the frustum and outside equally.
Spacetime reacts through the closed frame of the cavity and sees it just like it was energy being stretched into a black hole. Since a black hole doesn't pull or suck you in but space pushes you. In the example I posted the Big end would be away from the direction of push.
We know photons are effected by spacetime but can photons effect spacetime and how much is the question.
Shell
Let's stretch the modes a little longer to get my point across.
Or maybe this is why this shape might do better at a frustum?
An interesting analogy to compare "EM drive effect" to the gravitational/space-time gradient of a black hole. If enough of the analogy were to hold true, concentrating maximum energy near the frustum/wedge apex would help lend further credence for potentially optimizing the "EM drive effect". I'm guessing this is somewhere near StrongGR's (and/or possibly WarpTech's) theory... although McCulloch and NotSoSureOfIt seem to be much closer to the needed magnitude.
If the "EM drive effect" eventually gets established as "real", a theoretical explanation sounds like it could become the missing link between unification of gravity and electromagetism.
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#2530 by gustavo on 17 May, 2016 20:53
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SeeShells, I've been running some calculations based on laser traveling inside a cavity, and ploted the electric field x time on each impact point. And apparently, the distortion of the wavelength is the opposite of what you described, the wavelenght is compressed at the small OD.
I'm finishing a paper that will be published in a few days, and according with my algorithm, the EmDrive works indeed, with no secrets, it's just a matter of geometry and equations to get the numbers done.
PS. I'm getting thrust towards the small OD.
See the images attached
Greetings from Brazil!
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#2531 by SeeShells on 17 May, 2016 20:53
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Build update: I'm getting very close to being able to run some powered tests. Sorry Dr. Rodal, no self-contained batteries yet. I want to work on a way to hot-swap different frustums, and then start thinking about integrating all electronics and batteries onto the beam. It's not as simple as it sounds!
I built a laser mount for a tripod I had, where I will also mount the IR camera. The laser bounces off a first surface mirror attached to the bottom center of the pendulum beam - and hits the wall opposite approximately 30 feet away.
This system is very sensitive. I will need to wait 15 minutes or more between tests to let the pendulum go back to center (provided there is any movement at all).
Your right it's very sensitive.
Are you going to twist the wires to the magnetron, or run it like it is and then twist them?
Good luck!!!
Shell -
#2532 by Monomorphic on 17 May, 2016 20:57
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Are you going to twist the wires to the magnetron, or run it like it is and then twist them?
Shell
Twisting the wires torques the pendulum. Maybe I could braid them together with the ground.
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#2533 by SeeShells on 17 May, 2016 20:58
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SeeShells, I've been running some calculations based on laser traveling inside a cavity, and ploted the electric field x time on each impact point. And apparently, the distortion of the wavelength is the opposite of what you described, the wavelenght is compressed at the small OD.
Thanks for posting this info, I'll be looking forward to reading your paper! It sounds very interesting!
I'm finishing a paper that will be published in a few days, and according with my algorithm, the EmDrive works indeed, with no secrets, it's just a matter of geometry and equations to get the numbers done.
See the images attached
Shell -
#2534 by Monomorphic on 17 May, 2016 21:01
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SeeShells, I've been running some calculations based on laser traveling inside a cavity, and ploted the electric field x time on each impact point. And apparently, the distortion of the wavelength is the opposite of what you described, the wavelenght is compressed at the small OD.
I'm finishing a paper that will be published in a few days, and according with my algorithm, the EmDrive works indeed, with no secrets, it's just a matter of geometry and equations to get the numbers done.
PS. I'm getting thrust towards the small OD.
See the images attached
Greetings from Brazil!
Definitely let me know when your paper comes out, and post it here. I have also run a few sims bouncing lasers in cavities - but nothing as sophisticated as this.
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#2535 by SeeShells on 17 May, 2016 21:02
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I've taken the wires stuck them in a vice (10 ft of wire or so) and connected the other end to a electric drill and pulled tight and then wound them up very tight. After being twisted tight they don't torque but act as one wire.Are you going to twist the wires to the magnetron, or run it like it is and then twist them?
Shell
Twisting the wires torques the pendulum. Maybe I could braid them together with the ground.
Just a thought.
Shell -
#2536 by zen-in on 17 May, 2016 21:17
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Build update: I'm getting very close to being able to run some powered tests. Sorry Dr. Rodal, no self-contained batteries yet. I want to work on a way to hot-swap different frustums, and then start thinking about integrating all electronics and batteries onto the beam. It's not as simple as it sounds!
I built a laser mount for a tripod I had, where I will also mount the IR camera. The laser bounces off a first surface mirror attached to the bottom center of the pendulum beam - and hits the wall opposite approximately 30 feet away.
This system is very sensitive. I will need to wait 15 minutes or more between tests to let the pendulum go back to center (provided there is any movement at all).
Nice build! Is the wire connected tensioned and connected to the bottom of the frame? One preliminary test you can try is to lift the ground wire for the magnetron and just power the filament. Note how much the pendulum swings under that condition and use that as a baseline for cable-induced movement. High current in the filament leads will cause the leads to stiffen and try to straighten out. The low current HV not so much. If you do that test enough times and don't electrocute yourself (please be careful!!), you can subtract the average of those measurements from a similar average where the ground lead is connected and the cone is getting fed RF. Start with 10 tests of each and plot the delta as a single point. Then do 20, 30... and see what the trend is. -
#2537 by gustavo on 17 May, 2016 21:17
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Rodal, the "laser" model was used as a method to consider how the beam travel inside the cavity, but using microwave frequency.
I will review my solution. Thank you for your notes.
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#2538 by Rodal on 17 May, 2016 22:51
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SeeShells, I've been running some calculations based on laser traveling inside a cavity, and ploted the electric field x time on each impact point. And apparently, the distortion of the wavelength is the opposite of what you described, the wavelenght is compressed at the small OD.
Welcome to the forum.
I'm finishing a paper that will be published in a few days, and according with my algorithm, the EmDrive works indeed, with no secrets, it's just a matter of geometry and equations to get the numbers done.
PS. I'm getting thrust towards the small OD.
See the images attached
Greetings from Brazil!
EM Drive experiments have been conducted at microwave frequencies, not at optical frequencies using lasers.
Also, the "ray tracing method" commonly used in optics to get simple solutions, and sometimes shown in sketches as the one you reproduce in the sketch above to represent microwaves is not a good method of solution for this problem at microwave frequencies.
Please see: https://en.wikipedia.org/wiki/Ray_tracing_%28physics%29QuoteWhen applied to problems of electromagnetic radiation, ray tracing often relies on approximate solutions to Maxwell's equations that are valid as long as the light waves propagate through and around objects whose dimensions are much greater than the light's wavelength. Ray theory does not describe phenomena such as interference and diffraction, which require wave theory (involving the phase of the wave).
For an EM Drive, the wavelength is not much smaller than the cavity's dimensions and therefore the ray-tracing method is not appropriate. Actually, for the EM Drive, the situation at the small end is that the wavelength is often just short of the cutoff condition for an open waveguide. The cut-off condition has been much discussed in these threads.
Furthermore, resonance in a cavity is due to the interference of travelling waves counterpropagating (in opposite directions), which cannot be properly modeled by the ray-tracing method.
Your solution (getting smaller wavelength towards the small end) runs contrary to:
1) the known exact solution for resonance for truncated cone resonant microwave cavities
2) Computer models (COMSOL FEA, FEKO BEM, MEEP FDTD) for resonance, and for transient excitation for truncated cone resonant microwave cavities
3) known experiments for truncated cone resonant microwave cavities (Shawyer, etc.)
all of which show the wavelength to be smaller towards the large end.
The reason for the discrepancy is likely due to:
* inability of the ray method of solution to get the solution for this problem*
Your solution, using a ray-tracing method, may be appropriate at much higher frequencies (optical range) such that the wavelength is much, much smaller than the small diameter of the EM Drive.
Some NSF users have been contemplating doing experiments in the optical range, and your solution is certainly of interest in that frequency range.
Please see, for example
"Foundations of Microwave Engineering" by Robert E. Collin
"Field Theory of Guided Waves" Robert E. Collin
"Advanced Engineering Electromagnetics" Constantine Balanis
Thanks for your post. -
#2539 by Fugudaddy on 17 May, 2016 23:29
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I've taken the wires stuck them in a vice (10 ft of wire or so) and connected the other end to a electric drill and pulled tight and then wound them up very tight. After being twisted tight they don't torque but act as one wire.Are you going to twist the wires to the magnetron, or run it like it is and then twist them?
Shell
Twisting the wires torques the pendulum. Maybe I could braid them together with the ground.
Oddly, I have a wee bit of experience; not with making wire but with making rope.
If you want to be all specific about things for whatever reason, here's a couple of thoughts.
(Definition; a strand == a wire. Usually strands in rope are material like hemp, jute, cotton, nylon, etc. Wire is usually copper. Either can be single core (one piece of material) or multi-core (a twisted set of, well, more than one piece of material. There's more, of course, this is basic).
technique; using a drill isn't a bad idea, but it can stretch the strands and that can add torque to the finished product, so be slow and careful. Attach the wire to something that won't move (a vice isn't bad), and try to keep the lines as taut as possible as you're twisting it. When it's tight and straight and not twisting on itself, bind it straight across with electrical tape at each end.
If you're combining single core strands, then it doesn't matter what direction you twist them in. If you want to make it really secure, then wrap the bundle with a layer of electrical tape-- in the opposite direction of the twist. (not straight across or in the direction of the twist). That will make your new little rope nice tight and much more non-leaky of those pesky electrons. The tape isn't necessary, though, but it will prevent any gaps or extra twists if you want to be picky about such things.
If you're combining multi-core strands, then you have to be more careful that the strands you're combining are twisting in the same direction (ie. if you look at the strands ends, their twists are all left-hand or right hand). If you can't tell, bare a wee bit of the wire and twist it one direction or the other. It'll come apart one way, but not the other. Three strands would be better than two. It'll make a tighter, cleaner 'rope' because geometry. Two is okay, but more tendency to gap and torque. So once you've attached the wires to your solid object and the drill, you need to make sure that you're now twisting these wires in the same direction as the strands are going. That's important again because of gaps and torque and the 'evenness' of the finished product. If you're doing three, I would think that a wrap of tape- in the *opposite* direction of the twist isn't a bad thing.
The tape bit is optional, but will help make sure the new wire doesn't come apart anywhere. If you don't want to use tape, then stretch the wire and spray an adhesive lightly across the strands, stretch, bind off the ends, then allow to dry before the next step.
So then. Once ready, cut the wire at the ends anywhere beyond the tape. Get a pair of gloves, and pull the wire through your hands, between your fingers, to help stretch and 'work' it. Pull it through one way, the just start at the other end and pull it through again. Best to go in the direction of the tape if you used that so you're not pulling against the grain. Do this a few times to work out the bubbles and kinks and it should make your wire a bit more pliable and easier to work with.
Geek note: rope doesn't require adhesives like tape or glue because the strands of natural materials, at a small level, are very rough and fibrous. As they're twisted, they wrap around one another and bind tightly with a lot of friction at microscopic levels, and that's what keeps the string or rope held together.
Is all this necessary? perhaps. I come from a computer networking arena so understanding how wires work is part of the gig. For this purpose, though, doing all of this will keep wires together, keeping them close prevents interference from the outside and helps prevent attenuation or loss from inside, the 'length' of the paths are equal (though yeah at SoL we're talking tiny bits of time, though it can add up if we're trying to be precise here). The wires are bundled together so they're all affected by environmental factors the same way. There's probably other good reasons.
You can probably buy really super-nice wire and stuff, but if you've got decent strand to begin with, making your own isn't that hard to do.
Thanks for reading,
Ronald
