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#200 by PotomacNeuron on 26 Jul, 2018 00:18
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Found it, https://forum.nasaspaceflight.com/index.php?topic=39772.msg1536759#msg1536759
Just as you remembered, the problem was an inappropriate cos^2 term.
Thank you! I forgot that I had other ID's on the forum. -
#201 by TheTraveller on 26 Jul, 2018 01:57
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.....
There are 2 momentum transfer events involved. One upon photon impact and another when the photon is emitted. That is why the radiation pressure equation starts with 2.
The cosine loss is squared as there are 2 x cosine loss events that reduce the radiation pressure, one on impact and one on emit.
So the equation is correct and is why radiation pressure on the side walls and end plates inside a tapered cavity is not constant but drops much quicker than the diameter drop.
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#202 by meberbs on 26 Jul, 2018 02:47
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Did you even read my post? If you did, you would already realize that you picked the wrong equation. There literally is no reason in this situation to square the cosine......
There are 2 momentum transfer events involved. One upon photon impact and another when the photon is emitted. That is why the radiation pressure equation starts with 2.
The cosine loss is squared as there are 2 x cosine loss events that reduce the radiation pressure, one on impact and one on emit.
So the equation is correct and is why radiation pressure on the side walls and end plates inside a tapered cavity is not constant but drops much quicker than the diameter drop.
First, to be clear, there are not "two events." That is not how reflection of an electromagnetic wave from a metal surface works. For the purpose of calculating the momentum, there is no difference though, so lets break it down:
The first "event" imparts momentum in the direction perpendicular to the surface of (E/c) * cos(alpha), this gets added to the second "event" which imparts (E/c) * cos(alpha) as well, because it is departing at the same angle. When you add these together, you get 2*(E/c) * cos(alpha). Nothing gets squared. -
#203 by TheTraveller on 26 Jul, 2018 03:55
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Did you even read my post? If you did, you would already realize that you picked the wrong equation. There literally is no reason in this situation to square the cosine......
There are 2 momentum transfer events involved. One upon photon impact and another when the photon is emitted. That is why the radiation pressure equation starts with 2.
The cosine loss is squared as there are 2 x cosine loss events that reduce the radiation pressure, one on impact and one on emit.
So the equation is correct and is why radiation pressure on the side walls and end plates inside a tapered cavity is not constant but drops much quicker than the diameter drop.
First, to be clear, there are not "two events." That is not how reflection of an electromagnetic wave from a metal surface works. For the purpose of calculating the momentum, there is no difference though, so lets break it down:
The first "event" imparts momentum in the direction perpendicular to the surface of (E/c) * cos(alpha), this gets added to the second "event" which imparts (E/c) * cos(alpha) as well, because it is departing at the same angle. When you add these together, you get 2*(E/c) * cos(alpha). Nothing gets squared.
You are correct.
It is cos^2 in the case of a solar sail as the incident angle drops both area and momentum transfer. But in the case of an EmDrive end plate it is just reduced momentum transfer small end plate with small incident angle vs big end plate with larger incident angle as the same number of photons hits both the small and big end plates.
Glad to see you now understand the rad pressure inside a trappered resonant cavity is not the same for all the surface area as some have incorrectly assumed. ie the photons do not act like a fluid. -
#204 by meberbs on 26 Jul, 2018 06:55
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You are correct.
Thank you for finally acknowledging anything I have said, and accepting a correction. As PotomacNeuron pointed out, you are not the first one to make this specific mistake.Glad to see you now understand the rad pressure inside a trappered resonant cavity is not the same for all the surface area as some have incorrectly assumed. ie the photons do not act like a fluid.
I never said the pressure was constant everywhere. In fact due to mode shape, it is variable over any surface you pick in the cavity. What hasn't changed is that the net axial force on the sidewalls plus the force on the small end together exactly cancel the force on the large end.
(I did originally have confusion thinking Shawyer claimed force on the small end was somehow larger than the big end, since that is what would be required to accelerate the drive in the direction it supposedly moves.) -
#205 by TheTraveller on 26 Jul, 2018 07:33
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I never said the pressure was constant everywhere. In fact due to mode shape, it is variable over any surface you pick in the cavity. What hasn't changed is that the net axial force on the sidewalls plus the force on the small end together exactly cancel the force on the large end.
Yes the rad pressure varies as the mode varies and yes it is not constant over the surface. However you are incorrect in assuming all the rad pressure on the interior surfaces of an EmDrive sum to zero.
Have a look at this graphic of how a typical resonant photon impacts and emits itself off of the side walls and the end plates. Yes I know it is not what Roger has shared as the impact angle on the small end plate is larger than on the big end plate, so more rad pressure on the small end plate than the big end plate and the side wall rad pressure is basically very small.
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#206 by meberbs on 26 Jul, 2018 12:59
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There is no assumption that the forces sum to zero, it is a simple fact. It has been proven multiple ways.I never said the pressure was constant everywhere. In fact due to mode shape, it is variable over any surface you pick in the cavity. What hasn't changed is that the net axial force on the sidewalls plus the force on the small end together exactly cancel the force on the large end.
Yes the rad pressure varies as the mode varies and yes it is not constant over the surface. However you are incorrect in assuming all the rad pressure on the interior surfaces of an EmDrive sum to zero.
Have a look at this graphic of how a typical resonant photon impacts and emits itself off of the side walls and the end plates. Yes I know it is not what Roger has shared as the impact angle on the small end plate is larger than on the big end plate, so more rad pressure on the small end plate than the big end plate and the side wall rad pressure is basically very small.
Your diagram is not representative of a "typical" photon, because a "typical" photon acts like a wave not a particle in this situation. You can do a particle model if you want, and it will still conserve momentum if you actually do it right. Your first clue that something is wrong with your picture should be your obviously unphysical result of more pressure on the small plate than the large one. The issue is that you did not sketch a path consistent with incident and reflected angles equal to each other. Do that and things will start making more sense. Then you can do the math and add up the momentum from each transfer. With 6 reflections off the side wall per loop, and all of those reflections having the axial component of their momentum pointed in the same direction, you are not going to find the sidewall force contribution to be "small" -
#207 by TheTraveller on 26 Jul, 2018 22:11
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There is no assumption that the forces sum to zero, it is a simple fact. It has been proven multiple ways.I never said the pressure was constant everywhere. In fact due to mode shape, it is variable over any surface you pick in the cavity. What hasn't changed is that the net axial force on the sidewalls plus the force on the small end together exactly cancel the force on the large end.
Yes the rad pressure varies as the mode varies and yes it is not constant over the surface. However you are incorrect in assuming all the rad pressure on the interior surfaces of an EmDrive sum to zero.
Have a look at this graphic of how a typical resonant photon impacts and emits itself off of the side walls and the end plates. Yes I know it is not what Roger has shared as the impact angle on the small end plate is larger than on the big end plate, so more rad pressure on the small end plate than the big end plate and the side wall rad pressure is basically very small.
Your diagram is not representative of a "typical" photon, because a "typical" photon acts like a wave not a particle in this situation. You can do a particle model if you want, and it will still conserve momentum if you actually do it right. Your first clue that something is wrong with your picture should be your obviously unphysical result of more pressure on the small plate than the large one. The issue is that you did not sketch a path consistent with incident and reflected angles equal to each other. Do that and things will start making more sense. Then you can do the math and add up the momentum from each transfer. With 6 reflections off the side wall per loop, and all of those reflections having the axial component of their momentum pointed in the same direction, you are not going to find the sidewall force contribution to be "small"
The emission angle alters as the diameter alters. That is why the guide wavelength at the small end is longer than at the big end. As the diameter drops, the emission angle increases. At cutoff diameter, the emission angle causes the emitted photon to hit the opposite wall at such an angle that the photon reverses it's big to small propogation. Image attached is of a resonant cavity that has no small end plate. Instead the proton propogation is reversed via the just described cutoff action. BTW this action is what caused the eddy current ring at the small end to become much greater than on the small end plate. 2nd image is cutoff and the 3rd image is boarderline cutoff. Ideally the small end side wall eddy current ring is much weaker than the small end plate eddy current ring at in the 4th image
If you search in a good microwave engineering book, you will find the equation that describes the relationship between mode, freq, waveguide diameter and emission angle.
Yes you are correct, the rad pressure is greater on the small end plate than on the big end plate. This is why the EmDrive accelerates small end forward. The action/reaction occurs from the photons doing their impact and emit N3 events at each end plate with an overall N3 effect generation a net effect small end forward. There is some side wall force but it is small end directed and not big end directed. So the small side wall force actually adds to the overall small end forward action.
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#208 by meberbs on 27 Jul, 2018 02:22
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The emission angle alters as the diameter alters. That is why the guide wavelength at the small end is longer than at the big end. As the diameter drops, the emission angle increases.
Correlation, not causation between angle and diameter. The real causation is that incident angle equals reflected angle. (Still using the bouncing particle approximation rather than the wave equations you need to get all of the details right. It at least provides for easier intuition this way.)
Each bounce on the way to the small end, the angle becomes closer to perpendicular to the side walls due to the effect of the previous reflection and the angle between these walls. This translate into a shallow angle bounce of the end plate which leads to the reduced pressure there. The approximation of cutoff conditions as you described is a smooth continuation of this trend. No reason that this would suddenly become a bad thing.If you search in a good microwave engineering book, you will find the equation that describes the relationship between mode, freq, waveguide diameter and emission angle.
Yes, I have had classes where I had to derive those equations for waveguides. We are talking about a resonator, not a waveguide. In some ways more significantly, we are talking about an object with sloped sides. This significantly changes the boundary conditions, invalidating those equations.Yes you are correct, the rad pressure is greater on the small end plate than on the big end plate.
There seems to have been some sort of miscommunication. I have never said that there was more pressure on the small end than the large end. I said the exact opposite of that. Even Shawyer said the exact opposite of that once I read what he was saying more carefully.This is why the EmDrive accelerates small end forward.
No, since the correct statement is that there is less pressure on the small end, Shawyer's theory that ignores the sidewalls predicts movement in the wrong direction.There is some side wall force but it is small end directed and not big end directed.
Yes, it is small end directed, so it adds to the force from the small end, to have the same magnitude as the force on the big end, which is why if you do the math right you see that this kind of explanation does not result in force generation. (Remember, the force on the small end is clearly less than the force on the big end since the photon reflection from that end happens at more of a glancing angle.) -
#209 by Req on 27 Jul, 2018 06:44
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Sorry, this is completely off-topic, but this seems like the place to ask - would it be possible, given enough energy and infrastructure, to create a dynamic electromagnetic resonant cavity to focus say a 100km2 phased array into a maser that can arbitrarily point a powerful coherent beam in milliseconds or would you need to build a giant structure out of matter and mechanically steer it? And by possible I mean at least imaginable power requirements, say under 10,000GW.
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#210 by fran640 on 27 Jul, 2018 13:03
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Hello everyonw,
First time poster, though I have been following this thread for 3 or 4 years now. I am a portrait artist but I also have a degree in electromechanical engineering. This was my introduction.
I think I will be the voice of all the silent viewers like me, who are desesperate to know if the em-drive is working or not.
My opinion : At this point, I think debating the same theories ad infinitum and will not lead to any progress toward the ultimate goal which is determining if the signal is real or not.
I also make this post to congratulate everyone who has invested their time and money into working on a device or working on the physics of this thing. I don't think of many examples where sunday scientists put so much effort and dedication to a cause. From all the silent viewers, thank you.
I am looking forward to see the results of the main reaserch teams whu publish public papers (Dr. Tajmar, Dr White) as much as I am looking forward to hear about results of all the DIYers here, including forum member The Traveller which seems to have direct access to "the designer".
Meilleurs vœux, salutations sincères -
#211 by X_RaY on 27 Jul, 2018 21:23
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TT,
There is no assumption that the forces sum to zero, it is a simple fact. It has been proven multiple ways.I never said the pressure was constant everywhere. In fact due to mode shape, it is variable over any surface you pick in the cavity. What hasn't changed is that the net axial force on the sidewalls plus the force on the small end together exactly cancel the force on the large end.
Yes the rad pressure varies as the mode varies and yes it is not constant over the surface. However you are incorrect in assuming all the rad pressure on the interior surfaces of an EmDrive sum to zero.
Have a look at this graphic of how a typical resonant photon impacts and emits itself off of the side walls and the end plates. Yes I know it is not what Roger has shared as the impact angle on the small end plate is larger than on the big end plate, so more rad pressure on the small end plate than the big end plate and the side wall rad pressure is basically very small.
Your diagram is not representative of a "typical" photon, because a "typical" photon acts like a wave not a particle in this situation. You can do a particle model if you want, and it will still conserve momentum if you actually do it right. Your first clue that something is wrong with your picture should be your obviously unphysical result of more pressure on the small plate than the large one. The issue is that you did not sketch a path consistent with incident and reflected angles equal to each other. Do that and things will start making more sense. Then you can do the math and add up the momentum from each transfer. With 6 reflections off the side wall per loop, and all of those reflections having the axial component of their momentum pointed in the same direction, you are not going to find the sidewall force contribution to be "small"
The emission angle alters as the diameter alters. That is why the guide wavelength at the small end is longer than at the big end. As the diameter drops, the emission angle increases. At cutoff diameter, the emission angle causes the emitted photon to hit the opposite wall at such an angle that the photon reverses it's big to small propogation. Image attached is of a resonant cavity that has no small end plate. Instead the proton propogation is reversed via the just described cutoff action. BTW this action is what caused the eddy current ring at the small end to become much greater than on the small end plate. 2nd image is cutoff and the 3rd image is boarderline cutoff. Ideally the small end side wall eddy current ring is much weaker than the small end plate eddy current ring at in the 4th image
If you search in a good microwave engineering book, you will find the equation that describes the relationship between mode, freq, waveguide diameter and emission angle.
Yes you are correct, the rad pressure is greater on the small end plate than on the big end plate. This is why the EmDrive accelerates small end forward. The action/reaction occurs from the photons doing their impact and emit N3 events at each end plate with an overall N3 effect generation a net effect small end forward. There is some side wall force but it is small end directed and not big end directed. So the small side wall force actually adds to the overall small end forward action.
I did a few simulations on TE013 to compare the bandwidth of a truncated conical cavity and a equivalent cylindrical one at nearly the same frequency...
However, I notice that the result shows an interesting current pattern at the end plate as compared to the strength at the sidewall. The cut off frequency is well below the resonant frequency for the cylindrical cavity. Mesh size is chosen equal also in this simulations.
Ignore the tapered cavity for a moment please.
Can you explain why the current at the sidewall is much stronger as compared to the end plates while the diameters of the end plate(s) is much larger than the cut off diameter for TE01p in the case of the cylindrical resonator?
It should be stronger at the end plate when applying your theory due to the smaller current ring area at the end plate(s).
Thanks.
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#212 by flux_capacitor on 27 Jul, 2018 22:48
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Yes you are correct, the rad pressure is greater on the small end plate than on the big end plate. This is why the EmDrive accelerates small end forward. The action/reaction occurs from the photons doing their impact and emit N3 events at each end plate with an overall N3 effect generation a net effect small end forward. There is some side wall force but it is small end directed and not big end directed. So the small side wall force actually adds to the overall small end forward action.
Sorry Phil but I agree with meberbs: what you said is exactly the opposite of what Shawyer claims. Attached, an excerpt of his controversial theory paper from emdrive.com
showing an effect which, even if real, could never ever accelerate such a cavity small end leading*
* The only way I could see "Shawyer's effect" possible is according to McCulloch's idea, where he assumes (from an effect due to his fringe theory of quantised inertia) that the collective massive photons, i.e. the effective inertial mass that would be acquired by photons in resonant cavities, get "heavier" when travelling from small end to big end, and "lighter" when going back from big to small end. So the centre of mass of the cavity is continually being shifted by quantised inertia towards the wide end. This way, the cavity needs to react the opposite way to conserve momentum: it accelerates small end leading. As a side note, the radiation pressure becomes greater at the big end indeed, but since the two ends and the side wall are all rigidly connected together, RD does not play a role in the propulsion. Continuous shifting of COM would.
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#213 by TheTraveller on 28 Jul, 2018 08:05
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Can you explain why the current at the sidewall is much stronger as compared to the end plates while the diameters of the end plate(s) is much larger than the cut off diameter for TE01p in the case of the cylindrical resonator?
It should be stronger at the end plate when applying your theory due to the smaller current ring area at the end plate(s).
Thanks.
Hi XRay,
Consider the attached. Your answer is in the photon ray trace and how dual travelling waves generate the standing waves that cause the mode localised eddy current heating.
Note the guide wavelength / 4 equation. Knowing where the E field peak lobes and their null zones are located helps to define how the average photons much transit so their E fields can combine to generate the E field lobes, nulls and localised eddy current heating rings that Feko simulates.
Then do the same thing with a EmDrive resonant cavity to see the photon pathways and from that to see how a asymmetric tapered waveguide resonat cavity can generate asymmetic radiation pressure that accelerates an EmDrive small end forward.
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#214 by TheTraveller on 28 Jul, 2018 08:11
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Yes you are correct, the rad pressure is greater on the small end plate than on the big end plate. This is why the EmDrive accelerates small end forward. The action/reaction occurs from the photons doing their impact and emit N3 events at each end plate with an overall N3 effect generation a net effect small end forward. There is some side wall force but it is small end directed and not big end directed. So the small side wall force actually adds to the overall small end forward action.
Sorry Phil but I agree with meberbs: what you said is exactly the opposite of what Shawyer claims. Attached, an excerpt of his controversial theory paper from emdrive.com
showing an effect which, even if real, could never ever accelerate such a cavity small end leading*
* The only way I could see "Shawyer's effect" possible is according to McCulloch's idea, where he assumes (from an effect due to his fringe theory of quantised inertia) that the collective massive photons, i.e. the effective inertial mass that would be acquired by photons in resonant cavities, get "heavier" when travelling from small end to big end, and "lighter" when going back from big to small end. So the centre of mass of the cavity is continually being shifted by quantised inertia towards the wide end. This way, the cavity needs to react the opposite way to conserve momentum: it accelerates small end leading. As a side note, the radiation pressure becomes greater at the big end indeed, but since the two ends and the side wall are all rigidly connected together, RD does not play a role in the propulsion. Continuous shifting of COM would.
What can I say? Roger, in the early days, did not get it entirely correct.
Do the ray trace and figure out for yourself the angles and rad pressure generated.
What is very clear is that for microwave photons to propogate down a waveguide, they MUST bounce, ping, reflect, do impact/emit events, what every you wish to call it. No way do photons propogate in a waveguide from one end to the other without touching the side walls. So travelliing waves "travel" by pinging from side wall to side wall. Roger got that very wrong. By error or intention to confuse is not clear. But how photons propogate down a waveguide is very clear and Roger is wrong that they do not blounce from side wall to side wall. -
#215 by flux_capacitor on 28 Jul, 2018 10:52
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Yes you are correct, the rad pressure is greater on the small end plate than on the big end plate. This is why the EmDrive accelerates small end forward. The action/reaction occurs from the photons doing their impact and emit N3 events at each end plate with an overall N3 effect generation a net effect small end forward. There is some side wall force but it is small end directed and not big end directed. So the small side wall force actually adds to the overall small end forward action.
Sorry Phil but I agree with meberbs: what you said is exactly the opposite of what Shawyer claims. Attached, an excerpt of his controversial theory paper from emdrive.com
showing an effect which, even if real, could never ever accelerate such a cavity small end leading*
* The only way I could see "Shawyer's effect" possible is according to McCulloch's idea, where he assumes (from an effect due to his fringe theory of quantised inertia) that the collective massive photons, i.e. the effective inertial mass that would be acquired by photons in resonant cavities, get "heavier" when travelling from small end to big end, and "lighter" when going back from big to small end. So the centre of mass of the cavity is continually being shifted by quantised inertia towards the wide end. This way, the cavity needs to react the opposite way to conserve momentum: it accelerates small end leading. As a side note, the radiation pressure becomes greater at the big end indeed, but since the two ends and the side wall are all rigidly connected together, RD does not play a role in the propulsion. Continuous shifting of COM would.
What can I say? Roger, in the early days, did not get it entirely correct.
Do the ray trace and figure out for yourself the angles and rad pressure generated.
What is very clear is that for microwave photons to propogate down a waveguide, they MUST bounce, ping, reflect, do impact/emit events, what every you wish to call it. No way do photons propogate in a waveguide from one end to the other without touching the side walls. So travelliing waves "travel" by pinging from side wall to side wall. Roger got that very wrong. By error or intention to confuse is not clear. But how photons propogate down a waveguide is very clear and Roger is wrong that they do not blounce from side wall to side wall.
Finally you see some of Shawyer's mistakes. You may agree however that Shawyer's equations are based on Cullen's equations measuring the radiation pressure upon different plates put in waveguides of various cross-sections.
If Shawyer "got it wrong in the early days" then all his theory is wrong (as many people here point out). If the radiation pressure is not greater on the wide end, then the group velocity (which is related and used everywhere in his model) is not greater there, neither. Hence his "Design Factor" Df is wrong, the "Thrust equation" too, etc.
BTW this is not only "in the early days" as Shawyer still claims in his latest presentation you uploaded a few days ago that:
• F1 + F2 + Fw = 0 (radiation pressures on the big end, small end and on the side wall cancel out in the case of a standing wave, so no propulsive force)
• Fw = 0 (no sidewall force -or negligible- in the particular case of a travelling wavefront with spherically-shaped ends)
• F1 > F2 (radiation pressure on the big end is greater than radiation pressure on the small end)
See slide 11, attached. This is not some rough draft paper from "the early days". This is current "SPR theory" presented at TU Dresden, July 11, 2018.
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#216 by JohnFornaro on 28 Jul, 2018 12:50
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Mass does not know velocity.
Wouldn't this be part of the definition of inertia? -
#217 by X_RaY on 28 Jul, 2018 21:39
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The E-component of the ExH field has nothing to do with the wall currents, tangential E-fields are zero on the conductive wall. It is the H-component that causes the wall currents. You should know this as well.Can you explain why the current at the sidewall is much stronger as compared to the end plates while the diameters of the end plate(s) is much larger than the cut off diameter for TE01p in the case of the cylindrical resonator?
It should be stronger at the end plate when applying your theory due to the smaller current ring area at the end plate(s).
Thanks.
Hi XRay,
Consider the attached. Your answer is in the photon ray trace and how dual travelling waves generate the standing waves that cause the mode localised eddy current heating.
Note the guide wavelength / 4 equation. Knowing where the E field peak lobes and their null zones are located helps to define how the average photons much transit so their E fields can combine to generate the E field lobes, nulls and localised eddy current heating rings that Feko simulates.
Then do the same thing with a EmDrive resonant cavity to see the photon pathways and from that to see how a asymmetric tapered waveguide resonat cavity can generate asymmetic radiation pressure that accelerates an EmDrive small end forward.
https://forum.nasaspaceflight.com/index.php?topic=39214.msg1646352#msg1646352
No question, the ray trajectory point of view is a helpful but as a tool in this case only to calculate the wavelength inside of a waveguide. However, you take this tool and ignore the wave like nature of the photon on one hand by trying to apply the particle picture to explain what you think the possible thrust causes. On the other hand you are talking of traveling waves (which lead to the correct description of the problem).
I think there is no reason to apply the particle image to an AC-driven cavity resonator which is excited by a wavelength of the same order as its own dimensions.
My current understanding is that photons as well as all other quantums are excitations of the underlying background (zeropoint-) fields. They are no corpuscles at all in the sense of a massive ball.
Anyway, as others members pointed out so many times, if you would apply the particle point of view correctly by taking each relevant vector component into the equations you would get no thrust at all. This is what all energy&momentum conservation equations tell. Neglecting terms in the equations leads to false positive results.
Nowadays there are some other nice theories on the market which are consistent with known physics and that could much better explain what happens than your inconsistent explanations, assuming the thrust signals are real.
You need "new physics" or an action on something external to explain thrust for such a system.
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#218 by TheTraveller on 28 Jul, 2018 23:15
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See slide 11, attached. This is not some rough draft paper from "the early days". This is current "SPR theory" presented at TU Dresden, July 11, 2018.
What can I say?
Photons in an EmDrive propogate from one end plate to the other end plate and back again by pinging off the side walls. They DO NOT propogate directly from one end plate to the other. As such any statement that the photons do not impact the side walls is not correct.
Those pings cause some of the photons to impact on free electrons and increase their energy. Those photons are totally absorbed and not emitted and are the energy loss per cycle. Then the other photons H fields direct the flow of these energised free electrons. Have a look at the direction the current flows in the side wall rings. One flows CW, the next CCW and the next CW. Then go to the lower right control and alter the phase through 360 deg and see the current flow switch from CW, CCW, CW to CCW, CW, CCW as the H field polarity reverses.
Photons propogate down a waveguide by pinging off the side walls of the waveguide as my earlier drawing shows. This is basic microwave waveguide physics.
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#219 by TheTraveller on 28 Jul, 2018 23:30
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The E-component of the ExH field has nothing to do with the wall currents, tangential E-fields are zero on the conductive wall. It is the H-component that causes the wall currents. You should know this as well.
https://forum.nasaspaceflight.com/index.php?topic=39214.msg1646352#msg1646352
No question, the ray trajectory point of view is a helpful but as a tool in this case only to calculate the wavelength inside of a waveguide. However, you take this tool and ignore the wave like nature of the photon on one hand by trying to apply the particle picture to explain what you think the possible thrust causes. On the other hand you are talking of traveling waves (which lead to the correct description of the problem).
I think there is no reason to apply the particle image to an AC-driven cavity resonator which is excited by a wavelength of the same order as its own dimensions.
My current understanding is that photons as well as all other quantums are excitations of the underlying background (zeropoint-) fields. They are no corpuscles at all in the sense of a massive ball.
Anyway, as others members pointed out so many times, if you would apply the particle point of view correctly by taking each relevant vector component into the equations you would get no thrust at all. This is what all energy&momentum conservation equations tell. Neglecting terms in the equations leads to false positive results.
Nowadays there are some other nice theories on the market which are consistent with known physics and that could much better explain what happens than your inconsistent explanations, assuming the thrust signals are real.
You need "new physics" or an action on something external to explain thrust for such a system.
X_Ray,
You asked me to explain the result you got. Which I did.
The eddy current rings are caused by photons impacting on free electrons, being absorbed and not emitted. This photon loss to excited free electrons, which shortly turn into heat and IR photons are what causes the cavity energy loss / cycle.
The excited free electrons are then directionally controlled by the remaining photon H fields. Each eddy current ring rotates in the opposite direction to it's neighbours. ie CW, CCW, CW and then as the H field phase flips, CCW, CW, CCW.
I understand that some here may not like this information but is it what it is.
