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#3640
by
FattyLumpkin
on 07 Jul, 2016 18:54
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Hi X_Ray, I remember seeing this before, but didn't put it into my collection. Thank you, K PS: the question still remains: if I keep the frequency the same and slowly reduce the size of the frustum, will that same lower frequency at some point while slowly "shrinking" the frustum, stimulate the same resonant mode? The geometry of the frustum remains the same. K
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#3641
by
FattyLumpkin
on 07 Jul, 2016 19:30
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X_Ray, I'll respond to you PM shortly, but for the time being here are the two geometries I was hoping you could sim in your FEKO lite. Please let me know if you can fit them in? Monomorphic says he has the ability to scan images into to his full version , but I don't know about yours. please keep me advised. I can provide you with frequencies and dimensions. Please let me know what you need. K PS: I can attach a diagram to show RF ports for 2nd image. keep advised : )
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#3642
by
X_RaY
on 07 Jul, 2016 19:34
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Hi X_Ray, I remember seeing this before, but didn't put it into my collection. Thank you, K PS: the question still remains: if I keep the frequency the same and slowly reduce the size of the frustum, will that same lower frequency at some point while slowly "shrinking" the frustum, stimulate the same resonant mode? The geometry of the frustum remains the same. K
If you shrink the cavity (while keeping the same geometry) the resonant frequency (eigen resonance) for each mode will be higher.
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Sorry this kind of data import is not possible using the lite version of feko.
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#3643
by
FattyLumpkin
on 07 Jul, 2016 20:08
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X_Ray , we have already decreased the size of a given geometry and increased the frequency by calculation and were successful in simulating the appropriate mode (in the small geometry)
I'm not clear re your response. Would you please elaborate?
I think the question here is whether you can "get" (or scan) these cavity shapes into you program? I can provide you with dimensions and frequencies. Thanks, Kevin
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#3644
by
Rodal
on 07 Jul, 2016 20:14
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X_Ray, I'll respond to you PM shortly, but for the time being here are the two geometries I was hoping you could sim in your FEKO lite. Please let me know if you can fit them in? Monomorphic says he has the ability to scan images into to his full version , but I don't know about yours. please keep me advised. I can provide you with frequencies and dimensions. Please let me know what you need. K PS: I can attach a diagram to show RF ports for 2nd image. keep advised : )
Could you please elaborate as to your thruster philosophy and as to how are you able to use these FEKO analyses for designing a thruster ? Since there is no commonly accepted theory to justify thrust for a truncated cone..
.and the theories "out there" (Shawyer's and McCulloch) cannot handle the "flying saucer" geometry you are proposing?
The proposed "flying saucer" shape up for FEKO analysis
Thanks
I call it "flying saucer" because it reminds me of this on its side:
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#3645
by
keithpickering
on 07 Jul, 2016 20:23
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Perhaps the strangest (stupidest?) question I've ever asked (about Emdrive) Here goes: Can a frustum that resonates well in at a given frequency and mode also resonate well at a higher "harmonic" of the fundamental resonant frequency? Obviously not mechanical/sound.
Why "obviously not"? The body of a violin or a guitar is a resonant cavity, and will resonate well over several octaves (harmonics).
Leading to a sort of opposite of the question: If a frustum is reduced in size by 1/2 can is resonate in some sort of elemental "part" of the lower waveform/frequency?
There is a reason for this question: will disclose after response(s) Please respond! 
You have it reversed: making it smaller eliminates the lower frequencies, leaving the higher ones.
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#3646
by
X_RaY
on 07 Jul, 2016 20:32
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X_Ray , we have already decreased the size of a given geometry and increased the frequency by calculation and were successful in simulating the appropriate mode (in the small geometry)
I'm not clear re your response. Would you please elaborate?
I think the question here is whether you can "get" (or scan) these cavity shapes into you program? I can provide you with dimensions and frequencies. Thanks, Kevin
Hi X_Ray, I remember seeing this before, but didn't put it into my collection. Thank you, K PS: the question still remains: if I keep the frequency the same and slowly reduce the size of the frustum, will that same lower frequency at some point while slowly "shrinking" the frustum, stimulate the same resonant mode? The geometry of the frustum remains the same. K
my answer was:
If you shrink the cavity (while keeping the same geometry) the resonant frequency (eigen resonance) for each mode will be higher.
Again the answer is NO! Not the same but lower order modes like TE011 (if you start with TE012 and shrink the frustum, other modes will be excite the frustum while shrinking before TE011 reach its resonant point/dimensions as long as you keep the excitation frequency constant.)
Maybe there is some kind of misunderstanding?
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No I can not scan/import the sketch. Sorry.
Also Rodal is very right, we cannot really explain the anormalus force for a simple truncated frustum yet, closed and fired by microwaves. Why we should do step two before the first one ?
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#3647
by
Kenjee
on 07 Jul, 2016 20:42
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,,,Are you not seeing that we have something like 50% of whatever made the pendulum deviate in the first place still forcing (in the same direction) about 2 minutes after power was interrupted ?
Precisely the point I was making to SeeShells
And you made a good point although with Dave's setup it's very tough to discern what the anomaly is showing on the beam. He will be taking some suggestions into his next run that should make it easier to see what is going on.
I hated the way my beam would show up the pitch and the yaw of the beam on the laser affixed to the beam, trying to narrow out any meaningful data from the bouncing ball of laser light was very hard. Similar to Dave's pitching and rocking beam.
I came upon simple solution that will negate the pitch and minimize the roll just leaving the yaw or horizontal rotational moment on the laser and metered ruler.
It is a simple laser level outputting a line instead of a laser dot. The laser level is mounted on the center line of the torsion wire directly on the beam.
Shell
You can use any cylindrical glass to make dot into line laser. (wine glass stand
)
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#3648
by
dustinthewind
on 07 Jul, 2016 20:43
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Its difficult to describe without a chalkboard. I'll check back from time to time, but have put in a lot of long hours...time is a precious commodity. Thanks again.
I wanted to suggest a possibly simple improvement for Dave's experiment. There is talk about the thermal thrust displacement of his pendulum/frustum. I would think the displacement of air over time could be fairly long in period as opposed to an EM thrust. The idea is to let the frustum develop its thermal displacement of the pendulum which should be a fairly constant displacement.
This is if the thermal equilibrium and gradient can be kept about constant and the magnetron can be kept in lockThe EM thrust (if there is any) should be pulsed at the period of osculation for the pendulum. Under-dampening of the pendulum may be desirable in this situation. Basically, he won't be interested in the constant displacement of the pendulum but rather the period and amplitude of osculation for the pendulum. What would be needed is to take into account a dampened harmonic oscillator to derive the amount of force being applied. The nature of a harmonic oscillator should amplify the observation of any force if there is any.
If a test pulse of force is needed it may be possible to do this by winding a coil or solenoid and placing it near an aluminum/copper plate hanging from the pendulum. When the coil is turned on at a known number of turns and current a change in the magnetic field should develop counter-currents in the plate pushing the plate away. The solenoid could be pulsed at the frequency of the pendulum to test the system.
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#3649
by
Rodal
on 07 Jul, 2016 20:55
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Its difficult to describe without a chalkboard. I'll check back from time to time, but have put in a lot of long hours...time is a precious commodity. Thanks again.
I wanted to suggest a possibly simple improvement for Dave's experiment. There is talk about the thermal thrust displacement of his pendulum/frustum. I would think the displacement of air over time could be fairly long in period as opposed to an EM thrust. The idea is to let the frustum develop its thermal displacement of the pendulum which should be a fairly constant displacement.
The EM thrust (if there is any) should be pulsed at the period of osculation for the pendulum. Under-dampening of the pendulum may be desirable in this situation. Basically, he won't be interested in the constant displacement of the pendulum but rather the period and amplitude of osculation for the pendulum. What would be needed is to take into account a dampened harmonic oscillator to derive the amount of force being applied. The nature of a harmonic oscillator should amplify the observation of any force if there is any.
If a test pulse of force is needed it may be possible to do this by winding a coil or solenoid and placing it near an aluminum/copper plate hanging from the pendulum. When the coil is turned on at a known number of turns and current a change in the magnetic field should develop counter-currents in the plate pushing the plate away. The solenoid could be pulsed at the frequency of the pendulum to test the system.
Basically, the pendulum, like any dynamic system has a natural frequency (period). This period is trivial to measure: all the DIY experimenter needs is a stopwatch to measure the period of oscillation.,
If the forcing function has the same frequency (period) as the natural frequency (period) of the pendulum, one should get a
resonant response whose amplitude is only limited by the damping in the dynamic system.
The experimenter should pulse the EM Drive at the same frequency of the pendulum, just like pushing on a swing at the right frequency swings a child to ever higher amplitudes.
This is a very intelligent suggestion.
If there is no resonant response, there is no EM Drive thrust. Simple.
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#3650
by
FattyLumpkin
on 07 Jul, 2016 21:00
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Dr. Rodal, To the best of my understanding the Cannae design also argues for a mutable Quantum Vacuum (QV). The image (that you and I have attached) is of the Cannae design but with the "slots" having been removed. This was done based on the argument that they were ineffective per the EWL text data. Cannae argues that the asymmetry in the cavity "creates a bias" in the QV in an unequal/in-equal fashion and there by creates a unidirectional force.
I think it reasonable to explore this claim further by looking ay their first design and second design with "slots" removed. After all the EWL team was able to measure forces with the Cannae geometry. Indeed I have observed the COMSOL sim provided by EW (attached) and seen the sim attempted by Monomorphic. If memory serves I believe Monomorphic stated that he had to guess at some of the dimensions in his sim. As part of an in-depth study I have been examining what ever literature I can find re Cannae, and believe I could offer those who wish to perform sims with more exacting information re the geometries of various Cannae designs.
Monomorphic is quite busy now, and I've not received a response from him in this regard, I therefore contacted X_Ray to see if he could perform a sim with his lite version of FEKO.
, Kevin PS: I no longer have an image of Monomophics's sim. to attach...but as (aforementioned) I believe IMS he said that he guessed at the dimensions. I don't know how he arrived at them. , K
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#3651
by
SeeShells
on 07 Jul, 2016 21:02
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Shell
You can use any cylindrical glass to make dot into line laser. (wine glass stand )
Good idea, add X,Y level bubbles and "remove and wine" and I have a vertical laser line. Note, it's best to remove any fluids from the glass before you turn the stem horizontally to shine the laser into.
Shell
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#3652
by
Monomorphic
on 07 Jul, 2016 21:03
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Mistake on Dave's FEKO sims: Unfortunately, I accidentally used the wrong dimensions for my intial FEKO analysis of Dave's frustum and didn't notice until today.
I noticed this because I was going to run a sim with an HDPE insert as FattyLumpkin suggested earlier. The HDPE didn't quite line up so I went back to Dave's private message to check the dimensions. To my surprise and embarrassment, I had the measured dims wrong in FEKO. It was enough to make some difference.
I have now run a 1Mhz sweep from 2.44Ghz to 2.46Ghz. I am still seeing TM013 mode for most of the sweep, but the resonance pattern is looser starting at 2.46 and tightens up as it approaches 2.44. Notice the intense surface currents on the small end? That's what we saw with Dave's IR camera. Here is a video of the sweep:
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#3653
by
Rodal
on 07 Jul, 2016 21:07
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Dr. Rodal, To the best of my understanding the Cannae design also agues for a mutable Quantum Vacuum (QV). The image (that you and I have attached) is of the Cannae design but with the "slots" having been removed. This was done based on the argument that they were ineffective per the EWL text data. Cannae argues that the asymmetry in the cavity "creates a bias" in the QV in an unequal/in-equal fashion and there by creates a unidirectional force.
I think it reasonable to explore this claim further by looking ay their first design and second design with "slots" removed. After all the EWL team was able to measure forces with the Cannae geometry. Indeed I have observed the COMSOL sim provided by EW (attached) and seen the sim attempted by Monomorphic. If memory serves I believe Monomorphic stated that he had to guess at some of the dimensions in his sim. As part of an in-depth study I have been examining what ever literature I can find re Cannae, and believe I could offer those who wish to perform sims more exacting information re the geometries of various Cannae designs.
Monomorphic is quite busy now, and I've not received a response from him in this regard, I therefore contacted X_Ray to see if he could perform a sim with his lite version of FEKO.
, Kevin PS: I no longer have an image of Monomophics's sim. to attach...but as (aforementioned) I believe IMS he said that he guessed at the dimensions. I don't know how he arrived at them. , K
Under NASA Eagleworks theory, they posit that the Cannae drive you propose only works because it has a dielectric in the cylindrical extension to the side: like this:
But the shape you propose:
completely eliminates this cylindrical extension where the dielectric is located.
Hence under NASA Eagleworks theory you will get no thrust with that design.
Furthermore, Cannae submitted a new patent that had a dielectric on its very first claim after the experiments at NASA showed that the Cannae thrust was related to the dielectric.
All copper Cannae cavities now use a dielectric. (The superconducting ones are not made of copper because copper is not a superconducting material).
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#3654
by
FattyLumpkin
on 07 Jul, 2016 21:13
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Absolutely, the dielectric in one end. Also, I was not suggesting whatsoever that a dialectic could or should not be used in either of the above geometries. Step by step, was the intent re the Cannae designs.---This is why I suggested a dialectic insert for Dave's build: 1st to see if there would be a mode change, and 2nd to test before and after for evidence of force.
As I understand your point, Cannae is using a symmetrical cavity with a dielectric at one end, and this is the sole reason for the anomalous thrust measurement. While the frustum is a combination of asymmetry and presence of dialectic (somewhere in the cavity) that causes the anomalous thrust?
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#3655
by
Monomorphic
on 07 Jul, 2016 21:16
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Good idea, add X,Y level bubbles and "remove and wine" and I have a vertical laser line. Note, it's best to remove any fluids from the glass before you turn the stem horizontally to shine the laser into.
The only problem I see with using a line rather than a laser dot is that post processing the laser dot to extract information is easier than the straight line. It's more a complication than a problem. The signal to noise ratio will be higher and the process more tedious.
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#3656
by
FattyLumpkin
on 07 Jul, 2016 21:18
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Monomorphic, I was given 10 x 8 x 6.25 " for the dimensions of Dave's build, only to be recently corrected that the 8 is 8.1" height , K
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#3657
by
Monomorphic
on 07 Jul, 2016 21:20
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Monomorphic, I was given 10 x 8 x 6.25 " for the dimensions of Dave's build, only to be recently corrected that the 8 is 8.1" height , K
These are the measured dimensions:
ds = 6.25"
ld = 10.0"
height = 8.175"
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#3658
by
Monomorphic
on 07 Jul, 2016 22:18
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Just received the precision 250 Ω resistor, 0.1% tolerance, with ferrite choke from Dataq. This should greatly reduce the interference with the laser displacement sensor.
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#3659
by
xyzzy
on 07 Jul, 2016 22:26
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Actually, now that I stop to think about it the Traveller reported a "wow" signal after leaving his amplifier on all night feeding into the can while the rf source was turned off. He then pulsed a rf signal when he started his morning tests and his scale went over limited.
...
Actually everything was cold. Have a master AC off. What happened was I left the PowerAmp enable switched on and when I powered the whole system on, I got a thump and the battery powered scale went over limit, which I managed to repeat twice before my amp died from all the AC off and on cycles I did.
That looks very much like oscillation to me. Many RF amps turn out to be marginal under conditions that were not anticipated by the designers, some may actually start to oscillate without an input signal when the output hits a load with some particular characteristics that the amp's designer did not guard against.
Also the switch-on moment may be the "worst" moment in the amp's operation since that's where the internal signals have to transition from the "off" state through some short-time but potentially hazardous conditions (like output stage bias being out of regulation) to the steady state of normal operation.
Normally (hopefully) this transition should be very fast and the amp should get out of any critical condition before anything gets damaged. But if the amp encountered some instability during power-up that has resulted in resonance and full-power oscillation, it could get overloaded and kept on oscillating, while never reaching the steady state. In this case, it would very likely break down from uncontrolled overload after a short time, but during that short time, it would be outputting a power level into the frustum that can be much higher than the amp's maximum ratings (hence the breakdown). Also the frequency of the oscillation would have a strong dependency on the load characteristics and it would therefore be likely to hit a natural resonance frequency of the frustum.
Therefore it seems to me like you've got the amp oscillating by chance, possibly at some unintended frequency (though that frequency turned out to be resonant and particularly "effective") and at a power level much higher than what the amp was rated for - explaining a particularly strong but short-lived "effect".
)
