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#3440
by
SeeShells
on 02 Jul, 2016 14:44
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... it doesn't need the "must be running it in a vacuum" clause that's posted here, not yet, because there are many other things to do even before you go there.
Shell
Why is rfmwguy running this test with a magnetron outside the cavity, fully exposed to the air, heating the air around it?
How hot does the magnetron get? What does the magnetron do to the air around it?
Is the magnetron acting as a very inefficient heater of the air?
Has rfmwguy tried to correlate what he is measuring with the temperature of the magnetron ?
The Torsional Pendulum is mainly a horizontal rotational test bed that was done to try to negate out the many vibrational harmonics in a teeter todder balance beam but it doesn't entirely.
Let's take my build as an example. 
with even both ends of the torsional wire captured, oscillations can still be seen that are not horizontal in nature.
Depending on the way the beam is measured you might see this as part of beam settling back to zero.
With a hanging torsional pendulum not secured on the bottom you will see increased osculations that are not horizontal in nature and that will show up in the data.
I propose that is what we are seeing in rfmwguy's free hanging torsional pendulum wire test stand.
OK, those are called swinging oscillations of the pendulum (to differentiate them from the torsional oscillations). Their period is easy to calculate, particularly if rfmwguy's pendulum is free-hanging and not also supported at the bottom.
Anyway, experimenters measure, has rfmwguy measured the period of swinging oscillation for his pendulum?
What is the swinging pendulum's period for rfmwguy's pendulum?
That needs to be determined doesn't it?Maybe a laser mounted on the central pivot point to a target would shine a light on it with video?
He does have further testing to do, just like me, but you'll have to agree whatever the outcome he has started by securing a great looking signal to work with.
Shell
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#3441
by
Rodal
on 02 Jul, 2016 15:04
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...
That needs to be determined doesn't it?
Maybe a laser mounted on the central pivot point to a target would shine a light on it with video?
He does have further testing to do, just like me, but you'll have to agree whatever the outcome he has started by securing a great looking signal to work with.
Shell
OK, as you and TT are the ones that have been communicating at NSF EM Drive thread rfmwguy's tests, I look forward to your future reporting what is the period of oscillation in swinging motion of his pendulum.
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A laser is not really needed to measure the period of oscillation
if it is really the reason behind the very long period oscillations that take place after the magnetron is off.All it takes is eyes and a watch. All he has to do is to swing it to an angle and then measure with a watch how long it takes to swing back, preferably over many cycles and then take the average.
Such swinging oscillations were measured more than a hundred years ago in excellent tests without needing a laser (we are talking about oscillations whose period takes many, many minutes here ). Not much accuracy is needed for such a measurement
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#3442
by
lmbfan
on 02 Jul, 2016 15:13
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Just popping in to point out that a fairly easy to obtain source of mu metal is hard drives. If any old drives are lying around unused, it is relatively simple to crack them open and extract the mu metal plates (please note, the drive does not survive this operation). This is also a good source for very strong permanent magnets.
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#3443
by
SeeShells
on 02 Jul, 2016 15:21
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...
That needs to be determined doesn't it?
Maybe a laser mounted on the central pivot point to a target would shine a light on it with video?
He does have further testing to do, just like me, but you'll have to agree whatever the outcome he has started by securing a great looking signal to work with.
Shell
OK, as you and TT are the ones that have been communicating at NSF EM Drive thread rfmwguy's tests, I look forward to your future reporting what is the period of oscillation in swinging motion of his pendulum.
-------------------------------
A laser is not really needed to measure the period of oscillation if it is really the reason behind the very long period oscillations that take place after the magnetron is off.
All it takes is eyes and a watch.
Such swinging oscillations were measured more than a hundred years ago in excellent tests without needing a laser (we are talking about oscillations whose period takes many, many minutes here ).
We are trying to keep the fine people on NSF updated and answer what we can... 400,000 viewers have inquiring minds.
But Dr. Rodal we have shiny new lasers and video cameras so we can get better data and make more work for us to do.
I noticed with my testing of the torsion wire that the small oscillations were very hard to see with the naked eye.
I heard here in the US because it's a Holiday (4th of July) that Barley suds and fireworks don't mix well with serious lab tests and really what could go wrong?
I expect testing to slow down for a day or two.
Shell
PS: I see some higher frequency components in Dave's tests that need to be categorized and mapped. His beam weights in I believe around 26 pounds so I'm very interested in the higher frequencies and what they are from.
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#3444
by
SeeShells
on 02 Jul, 2016 15:35
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Just popping in to point out that a fairly easy to obtain source of mu metal is hard drives. If any old drives are lying around unused, it is relatively simple to crack them open and extract the mu metal plates (please note, the drive does not survive this operation). This is also a good source for very strong permanent magnets.
Forgot about them. GREAT IDEA!!!
My Best,
Shell
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#3445
by
Tellmeagain
on 02 Jul, 2016 18:02
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Just popping in to point out that a fairly easy to obtain source of mu metal is hard drives. If any old drives are lying around unused, it is relatively simple to crack them open and extract the mu metal plates (please note, the drive does not survive this operation). This is also a good source for very strong permanent magnets.
Forgot about them. GREAT IDEA!!!
My Best,
Shell
According to wikipedia, those are made of aluminium or glass or ceramic substrate.
https://en.wikipedia.org/wiki/Hard_disk_drive_platter
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#3446
by
SeeShells
on 02 Jul, 2016 18:25
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Just popping in to point out that a fairly easy to obtain source of mu metal is hard drives. If any old drives are lying around unused, it is relatively simple to crack them open and extract the mu metal plates (please note, the drive does not survive this operation). This is also a good source for very strong permanent magnets.
Forgot about them. GREAT IDEA!!!
My Best,
Shell
According to wikipedia, those are made of aluminium or glass or ceramic substrate. https://en.wikipedia.org/wiki/Hard_disk_drive_platter
I know, some of the machines I built were used to build hard drives. I totally spaced the magnets and the Mu Metal for shielding used in other spaces in the drive.
Shell
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#3447
by
FattyLumpkin
on 02 Jul, 2016 19:17
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Have contacted rfmwguy re his testing regime: he informs he will be locating "aiming/placing" his second Gen RC in various directions and positions, and making several data runs for every change . TBMK I believe he also intends to employ an on-board solid-state RF/source/power pack to perform additional testing. While a certain amount of consternation is expected under the circumstances (EM-drive research to date), waiting for all of the test data to come in, evaluating materials and methods etc. might be the most appropriate.
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#3448
by
keithpickering
on 02 Jul, 2016 19:26
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Roger developed a Df or Design factor that deals with the way the big and small ends behave. It is part of his thrust equation F = (2 Qu Pwr Df) / c. As the small end diameter decreases, the guide wavelength increases and the Df increases. As the big end diameter increases, the guide wavelength decreases and the Df increases. Max Df = 1. When small end is at or below cutoff diameter, the Df = 0. Design goal is to make the small end diameter as small as possible while operating just above cutoff diameter and for the big end diameter to be as big as possible.
MiHsC gives the same prediction: to maximize thrust, make the big end bigger and the small end smaller.
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#3449
by
X_RaY
on 02 Jul, 2016 19:30
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Roger developed a Df or Design factor that deals with the way the big and small ends behave. It is part of his thrust equation F = (2 Qu Pwr Df) / c. As the small end diameter decreases, the guide wavelength increases and the Df increases. As the big end diameter increases, the guide wavelength decreases and the Df increases. Max Df = 1. When small end is at or below cutoff diameter, the Df = 0. Design goal is to make the small end diameter as small as possible while operating just above cutoff diameter and for the big end diameter to be as big as possible.
MiHsC gives the same prediction: to maximize thrust, make the big end bigger and the small end smaller.
All known different thrust equations for the EM-Drive predict that beside a false infinite thrust generation for a pointed cone.
The only restriction was given by TT and Sawyer to their magic 0.82 cutoff rule for TE01p modes.
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#3450
by
keithpickering
on 02 Jul, 2016 19:34
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After disassembling oven #1, I find that the "pointy" end of the magnetron [a Samsung 0M75P(31)] is the south pole, and the "flat" end of the magnetron is the north pole. So that will create a magnetic couple with the Earth's magnetic field, unless steps are taken.
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#3451
by
keithpickering
on 02 Jul, 2016 19:36
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Roger developed a Df or Design factor that deals with the way the big and small ends behave. It is part of his thrust equation F = (2 Qu Pwr Df) / c. As the small end diameter decreases, the guide wavelength increases and the Df increases. As the big end diameter increases, the guide wavelength decreases and the Df increases. Max Df = 1. When small end is at or below cutoff diameter, the Df = 0. Design goal is to make the small end diameter as small as possible while operating just above cutoff diameter and for the big end diameter to be as big as possible.
MiHsC gives the same prediction: to maximize thrust, make the big end bigger and the small end smaller.
All known different thrust equations for the EM-Drive predict that beside a false infinitive thrust generation for a pointed cone.
Not really, since a pointy-ended cavity will not resonate at all (the photons get lost down the rabbit hole and don't come back out). So Q drops to zero.
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#3452
by
X_RaY
on 02 Jul, 2016 19:42
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Roger developed a Df or Design factor that deals with the way the big and small ends behave. It is part of his thrust equation F = (2 Qu Pwr Df) / c. As the small end diameter decreases, the guide wavelength increases and the Df increases. As the big end diameter increases, the guide wavelength decreases and the Df increases. Max Df = 1. When small end is at or below cutoff diameter, the Df = 0. Design goal is to make the small end diameter as small as possible while operating just above cutoff diameter and for the big end diameter to be as big as possible.
MiHsC gives the same prediction: to maximize thrust, make the big end bigger and the small end smaller.
All known different thrust equations for the EM-Drive predict that beside a false infinitive thrust generation for a pointed cone.
Not really, since a pointy-ended cavity will not resonate at all (the photons get lost down the rabbit hole and don't come back out). So Q drops to zero.
What? It will resonate!
Again all till now known formulas predict infiniti thrust for a pointed cone! On the other hand we are dealing with different modes therefore different energy densities at the pointed location. The Q dont drops to zero, it cant.
Please wait a minute I will make a FEKO simulation.
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#3453
by
keithpickering
on 02 Jul, 2016 19:53
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Roger developed a Df or Design factor that deals with the way the big and small ends behave. It is part of his thrust equation F = (2 Qu Pwr Df) / c. As the small end diameter decreases, the guide wavelength increases and the Df increases. As the big end diameter increases, the guide wavelength decreases and the Df increases. Max Df = 1. When small end is at or below cutoff diameter, the Df = 0. Design goal is to make the small end diameter as small as possible while operating just above cutoff diameter and for the big end diameter to be as big as possible.
MiHsC gives the same prediction: to maximize thrust, make the big end bigger and the small end smaller.
All known different thrust equations for the EM-Drive predict that beside a false infinitive thrust generation for a pointed cone.
Not really, since a pointy-ended cavity will not resonate at all (the photons get lost down the rabbit hole and don't come back out). So Q drops to zero.
What? It will resonate!
Again all till now known formulas predict infiniti thrust for a pointed cone! On the other hand we are dealing with different modes therefore different energy densities at the pointed location. The Q dont drops to zero, it cant.
Please wait a minute I will make a FEKO simulation.
OK, point taken, Q can't drop all the way to zero. But it should drop very low, i.e., lower than a frustum. As a photon approaches the point, it's going to be doing a LOT of bouncing off the walls, each bounce being another possibility of dissipation. And that effect accelerates the closer you get to the point. So yeah, a lot of photons are going to get lost down there. Bad Q = bad thrust.
UPDATE:
Or, think of it this way:
Imagine a cone/frustum with a very, very gentle angle, so that it's just barely not-cylindrical. As you move toward the point the diameter gets smaller, and eventually you're going to reach a diameter where the cylinder can no longer act as a waveguide for photons of your frequency: all the photons will dissipate. If you haven't hit the small end before reaching that point, the thrust you get will be too small to measure, because Q will be really small. There will still be some energy in the cavity, so it won't be zero. But it won't be much.
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#3454
by
meberbs
on 02 Jul, 2016 20:16
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...
OK, point taken, Q can't drop all the way to zero. But it should drop very low, i.e., lower than a frustum. As a photon approaches the point, it's going to be doing a LOT of bouncing off the walls, each bounce being another possibility of dissipation. And that effect accelerates the closer you get to the point. So yeah, a lot of photons are going to get lost down there. Bad Q = bad thrust.
It doesn't work like that.
First we are dealing with a cavity on the order of the wavelength, so "bounces" isn't a particularly meaningful model at this scale.
Second, there would be no particularly large number of bounces happening even if you assumed a bounce model (plotted the path of a small laser beam). You can try to draw out some examples yourself. I would do it, but I feel that you would learn more by working it out yourself.
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#3455
by
X_RaY
on 02 Jul, 2016 20:29
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Roger developed a Df or Design factor that deals with the way the big and small ends behave. It is part of his thrust equation F = (2 Qu Pwr Df) / c. As the small end diameter decreases, the guide wavelength increases and the Df increases. As the big end diameter increases, the guide wavelength decreases and the Df increases. Max Df = 1. When small end is at or below cutoff diameter, the Df = 0. Design goal is to make the small end diameter as small as possible while operating just above cutoff diameter and for the big end diameter to be as big as possible.
MiHsC gives the same prediction: to maximize thrust, make the big end bigger and the small end smaller.
All known different thrust equations for the EM-Drive predict that beside a false infinitive thrust generation for a pointed cone.
Not really, since a pointy-ended cavity will not resonate at all (the photons get lost down the rabbit hole and don't come back out). So Q drops to zero.
What? It will resonate!
Again all till now known formulas predict infiniti thrust for a pointed cone! On the other hand we are dealing with different modes therefore different energy densities at the pointed location. The Q dont drops to zero, it cant.
Please wait a minute I will make a FEKO simulation.
OK, point taken, Q can't drop all the way to zero. But it should drop very low, i.e., lower than a frustum. As a photon approaches the point, it's going to be doing a LOT of bouncing off the walls, each bounce being another possibility of dissipation. And that effect accelerates the closer you get to the point. So yeah, a lot of photons are going to get lost down there. Bad Q = bad thrust.
UPDATE:
Or, think of it this way:
Imagine a cone/frustum with a very, very gentle angle, so that it's just barely not-cylindrical. As you move toward the point the diameter gets smaller, and eventually you're going to reach a diameter where the cylinder can no longer act as a waveguide for photons of your frequency: all the photons will dissipate. If you haven't hit the small end before reaching that point, the thrust you get will be too small to measure, because Q will be really small. There will still be some energy in the cavity, so it won't be zero. But it won't be much.
We are dealing with microwave cavities where the wavelength is of the same order of the cavity itself. It is a microwave circuit and can be described as RLC composition.
The Quality factor of the resonator is part of the thrust equations and its quite logical that it has to take into account.
The Q of such a resonant circuit depends on a number of parameters, not on the fact that there is a small end plate at all in such a situation.
1) surface resistivity
2) surface to volume ratio
3) frequency
4) mode order
5) tand of the medium inside the cavity
6) coupling factor/ external Q
7) ...
The picture below shows a short 5 minutes feko run for a random geometry and shows a TE02 mode.
EDIT
Please also note the pdf below
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#3456
by
Tcarey
on 02 Jul, 2016 21:02
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...And it is evident from rfmguy's picture that at the moment he can have no idea of what mode shape (if any) is being excited...
Dave's VNA S11 rtn loss scan shows a very high Q dip where TE013 resonance would be expected. But his antenna placement can't excite TE013 but can excite TM113 which exists at the same resonant freq as TE013.
He also knows the cold maggie freq is above this resonant freq and that his maggie needs to warm up a bit, to drop it's freq to get pull lock with the high Q frustum, which can be seen on his 1st test run as attached.
Please note in this zoomed in image, AC filament current and DC anode current flowed over the feed wires for approx 30 sec, until the maggie warmed, freq dropped enough to get lock and force was generated. If you look close you can see a very slight drop in the cold base line as DC anode current flowed and probably generated a very small Lorentz force.
Should also add that over those 1st 30 seconds, there was 900Wrf being injected into the frustum by a maggie antenna INSIDE the frustum, yet there is no sign of any movement of the base line as the frustum heated up prior to achieving freq lock and generating a "Shawyer Effect" thrust output.
At lease in those 1st 30 secs, starting with a ambient temp maggie,, there doesn't appear to be any significant Lorentz or thermal forces active as the base line is flat.
TT. I'd like you comments on rfmwguys results with an eye towards something you posted earlier that the frequency bandwidth that generates thrust is smaller than the overall possible resonance bandwidth of the system. What I am wondering about is the frequency drift and splatter that the maggie produces when driven with the type power supply being used. It would seem to me that two things might be happening, first the splatter makes it more likely that the thrust producing frequency will be hit and second, when it is hit there will be a lot less power at the frequency resulting in less thrust.
Your thoughts please?
The natural maggie freq splatter can be pulled into the bandwidth of a high Q load. However the pulling introduces forward power losses versus the amount of pulling. Most maggie data sheets have a pulling chart.
So it is complex, well maybe almost impossible to calculate the energy versus freq splatter that can form resonance.
Dave has done external leakage spectrum analysis, which visually shows the unlocked freq splatter becoming locked and actually painting the frustum bandwidth on the screen. I'll find an image of that and post.
Commercial maggie are cooled and operational temperature controlled to stop freq drift lower as the maggie heats. Then the anode current is highly regulated to stop freq pushing drift from anode current variance. Next, after a few seconds, filament current us backed down to zero to further eliminate freq splatter. Have seen maggie output spectrums with +-5kHz bandwidth.
Dave's measured S11 VNA resonance is a, I think, around 50MHz below the maggie cold output and via spectrum scanner there is no freq pulled lock as it is too far above the narrow frustum bandwidth. But as the maggie warms and the freq drops, you can see the maggie freq splatter being pulled into the frustum's bandwidth. He has videos of this happening.
So while Dave's maggie & frustum can only engage in a short lock, the effect of the lock is VERY clear.
Thanks for the reply. I do understand the point you are making. However that is not really addressing the question I was trying to get at. TT has said that the frequency range for a frustum that produced thrust is narrower than the bandwidth that a frustum can be resonated to. If that is the case then small changes in the injected frequency can make the difference between thrust and no thrust even though the frustum is showing resonance. If the maggie is generating a less pure output then it seems to me that you have a better chance of hitting that narrower frequency band that generates thrust. Obviously a maggie that has the changes you suggest would produce more thrust if it's output is tuned to that particular sub band. At the same time if that narrower output is not in the sub band there would be little or no thrust.
If TT is correct then arranging a frequency sweep of the resonance band would be in order.
So many variables.....
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#3457
by
X_RaY
on 02 Jul, 2016 21:08
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...And it is evident from rfmguy's picture that at the moment he can have no idea of what mode shape (if any) is being excited...
Dave's VNA S11 rtn loss scan shows a very high Q dip where TE013 resonance would be expected. But his antenna placement can't excite TE013 but can excite TM113 which exists at the same resonant freq as TE013.
He also knows the cold maggie freq is above this resonant freq and that his maggie needs to warm up a bit, to drop it's freq to get pull lock with the high Q frustum, which can be seen on his 1st test run as attached.
Please note in this zoomed in image, AC filament current and DC anode current flowed over the feed wires for approx 30 sec, until the maggie warmed, freq dropped enough to get lock and force was generated. If you look close you can see a very slight drop in the cold base line as DC anode current flowed and probably generated a very small Lorentz force.
Should also add that over those 1st 30 seconds, there was 900Wrf being injected into the frustum by a maggie antenna INSIDE the frustum, yet there is no sign of any movement of the base line as the frustum heated up prior to achieving freq lock and generating a "Shawyer Effect" thrust output.
At lease in those 1st 30 secs, starting with a ambient temp maggie,, there doesn't appear to be any significant Lorentz or thermal forces active as the base line is flat.
TT. I'd like you comments on rfmwguys results with an eye towards something you posted earlier that the frequency bandwidth that generates thrust is smaller than the overall possible resonance bandwidth of the system. What I am wondering about is the frequency drift and splatter that the maggie produces when driven with the type power supply being used. It would seem to me that two things might be happening, first the splatter makes it more likely that the thrust producing frequency will be hit and second, when it is hit there will be a lot less power at the frequency resulting in less thrust.
Your thoughts please?
The natural maggie freq splatter can be pulled into the bandwidth of a high Q load. However the pulling introduces forward power losses versus the amount of pulling. Most maggie data sheets have a pulling chart.
So it is complex, well maybe almost impossible to calculate the energy versus freq splatter that can form resonance.
Dave has done external leakage spectrum analysis, which visually shows the unlocked freq splatter becoming locked and actually painting the frustum bandwidth on the screen. I'll find an image of that and post.
Commercial maggie are cooled and operational temperature controlled to stop freq drift lower as the maggie heats. Then the anode current is highly regulated to stop freq pushing drift from anode current variance. Next, after a few seconds, filament current us backed down to zero to further eliminate freq splatter. Have seen maggie output spectrums with +-5kHz bandwidth.
Dave's measured S11 VNA resonance is a, I think, around 50MHz below the maggie cold output and via spectrum scanner there is no freq pulled lock as it is too far above the narrow frustum bandwidth. But as the maggie warms and the freq drops, you can see the maggie freq splatter being pulled into the frustum's bandwidth. He has videos of this happening.
So while Dave's maggie & frustum can only engage in a short lock, the effect of the lock is VERY clear.
Thanks for the reply. I do understand the point you are making. However that is not really addressing the question I was trying to get at. TT has said that the frequency range for a frustum that produced thrust is narrower than the bandwidth that a frustum can be resonated to. If that is the case then small changes in the injected frequency can make the difference between thrust and no thrust even though the frustum is showing resonance. If the maggie is generating a less pure output then it seems to me that you have a better chance of hitting that narrower frequency band that generates thrust. Obviously a maggie that has the changes you suggest would produce more thrust if it's output is tuned to that particular sub band. At the same time if that narrower output is not in the sub band there would be little or no thrust.
If TT is correct then arranging a frequency sweep of the resonance band would be in order.
So many variables.....
The good news is, it's testable with a stable PLL controlled source with a slow frequency sweep and a frustum on a torsion pendulum.
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#3458
by
X_RaY
on 02 Jul, 2016 21:14
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Roger developed a Df or Design factor that deals with the way the big and small ends behave. It is part of his thrust equation F = (2 Qu Pwr Df) / c. As the small end diameter decreases, the guide wavelength increases and the Df increases. As the big end diameter increases, the guide wavelength decreases and the Df increases. Max Df = 1. When small end is at or below cutoff diameter, the Df = 0. Design goal is to make the small end diameter as small as possible while operating just above cutoff diameter and for the big end diameter to be as big as possible.
MiHsC gives the same prediction: to maximize thrust, make the big end bigger and the small end smaller.
All known different thrust equations for the EM-Drive predict that beside a false infinitive thrust generation for a pointed cone.
Not really, since a pointy-ended cavity will not resonate at all (the photons get lost down the rabbit hole and don't come back out). So Q drops to zero.
What? It will resonate!
Again all till now known formulas predict infiniti thrust for a pointed cone! On the other hand we are dealing with different modes therefore different energy densities at the pointed location. The Q dont drops to zero, it cant.
Please wait a minute I will make a FEKO simulation.
OK, point taken, Q can't drop all the way to zero. But it should drop very low, i.e., lower than a frustum. As a photon approaches the point, it's going to be doing a LOT of bouncing off the walls, each bounce being another possibility of dissipation. And that effect accelerates the closer you get to the point. So yeah, a lot of photons are going to get lost down there. Bad Q = bad thrust.
UPDATE:
Or, think of it this way:
Imagine a cone/frustum with a very, very gentle angle, so that it's just barely not-cylindrical. As you move toward the point the diameter gets smaller, and eventually you're going to reach a diameter where the cylinder can no longer act as a waveguide for photons of your frequency: all the photons will dissipate. If you haven't hit the small end before reaching that point, the thrust you get will be too small to measure, because Q will be really small. There will still be some energy in the cavity, so it won't be zero. But it won't be much.
NO the wave will be reflected in the opposite direction.
The dimensions at the cut off diameter cannot satisfy Pi/2 at this point (for a given frequency and mode). At the same time the reflection coefficient increases and act as a short and the wave will reflected at this point*.
* the evanecet part of the wave still penetrates this barrier but decay wihin a short distance
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#3459
by
FattyLumpkin
on 02 Jul, 2016 22:55
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X_Ray, The attached geometry #1 should resonate in TE012 at +/-2.45 GHz with extruded HDPE dielectric resonator/disks (same as NASA frustum). The question I have is: will TE012 be excited in this geometry by steady clean maggie flow image #2 (attached) as demonstrated by Shell. And in what location would/should the maggie RF be "fed into" ...top, bottom, side of the frustum? As you can see in image #3 the antenna is located on the side, and I calculate it to be located 1/4 of the cavity height from the bottom of the cavity. Agreed? Frustum size can be made slightly larger to accommodate 2.43189 GHz if needed. Pickering comments below suggested I calculate the Q of this "smaller" RC...Am coming up with something +/- 14,000-15,000 + dimensions not showing as well as I'd like in the schematic, therefore Small diameter= 12.1841 cm, Height= 17.545 cm and Bottom diameter= 21.444 cm Frequency +/- 2.45 GHz
HDPE dielectric disks (top of frustum) dimensions = 12.027 x 4.145 cm
