Author Topic: EM Drive Developments - related to space flight applications - Thread 3  (Read 2304557 times)

zellerium

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Re: EM Drive Developments - related to space flight applications - Thread 3
« Reply #2300 on: 06/23/2015 03:29 AM »
...

That is not an option that I see in the h5topng manual. Maybe HDFview has that option but I think you're asking for some MatLab data processing. If so, then no, I can't, maybe someone else would like to accept the challenge. I know that Meep users commonly reduce data using MatLab programs so it's likely possible.

aero,
I am very comfortable with Matlab data processing, if you want to send me the data I'd happily do some contours, plot3 or anything else you all are looking for. My email is [email protected]

However it might take me a day or two, I'm back home visiting family.

Kurt

Rodal

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Re: EM Drive Developments - related to space flight applications - Thread 3
« Reply #2301 on: 06/23/2015 03:40 AM »
...
. No end needs to be open, microwaves can escape with the whole resonator closed.
Microwaves can penetrate a sheet of copper?
What happened to the safety of home-cooking microwaves ?

Rodal

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Re: EM Drive Developments - related to space flight applications - Thread 3
« Reply #2302 on: 06/23/2015 03:44 AM »
....

Let's try to work through this.  The standard convention is to take z as the axis of symmetry (the longitudinal axis of the cone) but the way you labeled them, it looks like x is your axis of symmetry, is that correct?

If x is the axis of symmetry, then y and z are perpendicular to it.
On the trapezium-looking cross section with axis y perpendicular to it, the axis of the trapezium are x and z, is that correct?

OK, if the answer is yes, on your y plot, what are you plotting:

Ex ?

Ez?

Hx?

Hz?

X is the axis of symmetry. The antenna is to the +Y edge of the cavity. Z completes the coordinate system.

I am plotting a snap shot of the x, y and z corrdinate values of the Ez field. More than that you'd have to ask a physicist.
Can you plot the Absolute Value of the E field:

for example, for the cross-section with normal y

instead of Ez, can you have contour plot Sqrt[(Ex)^2 + (Ez)^2]

That is not an option that I see in the h5topng manual. Maybe HDFview has that option but I think you're asking for some MatLab data processing. If so, then no, I can't, maybe someone else would like to accept the challenge. I know that Meep users commonly reduce data using MatLab programs so it's likely possible.

Your Ex component should be zero (I keep forgetting that you are using x for the longitudinal axis)

There should only be a magnetic field Hx component in the longitudinal direction for x for TE modes.

That's why it is called Transverse Electric: there should not be an electric field in the longitudinal direction

It is for a circular cross section with normal x you need to plot Sqrt[Ez^2+Ey^2]

Can you give us a plot of the Hx field for the TE mode?

« Last Edit: 06/23/2015 03:49 AM by Rodal »

aero

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Re: EM Drive Developments - related to space flight applications - Thread 3
« Reply #2303 on: 06/23/2015 04:15 AM »
....

Let's try to work through this.  The standard convention is to take z as the axis of symmetry (the longitudinal axis of the cone) but the way you labeled them, it looks like x is your axis of symmetry, is that correct?

If x is the axis of symmetry, then y and z are perpendicular to it.
On the trapezium-looking cross section with axis y perpendicular to it, the axis of the trapezium are x and z, is that correct?

OK, if the answer is yes, on your y plot, what are you plotting:

Ex ?

Ez?

Hx?

Hz?

X is the axis of symmetry. The antenna is to the +Y edge of the cavity. Z completes the coordinate system.

I am plotting a snap shot of the x, y and z corrdinate values of the Ez field. More than that you'd have to ask a physicist.
Can you plot the Absolute Value of the E field:

for example, for the cross-section with normal y

instead of Ez, can you have contour plot Sqrt[(Ex)^2 + (Ez)^2]

That is not an option that I see in the h5topng manual. Maybe HDFview has that option but I think you're asking for some MatLab data processing. If so, then no, I can't, maybe someone else would like to accept the challenge. I know that Meep users commonly reduce data using MatLab programs so it's likely possible.

Your Ex component should be zero (I keep forgetting that you are using x for the longitudinal axis)

There should only be a magnetic field Hx component in the longitudinal direction for x for TE modes.

That's why it is called Transverse Electric: there should not be an electric field in the longitudinal direction

It is for a circular cross section with normal x you need to plot Sqrt[Ez^2+Ey^2]

Can you give us a plot of the Hx field for the TE mode?

I'm thinking that we need to consider the coordinate systems in a little more detail. The origon of the of the EM fields is the location of the antenna. The x, y, and z coordinates of the EM fields start at that origin. The fields do pass through the origon of the cavity which is on the central axis of rotation equidistant from the ends.

Meep calculates from the origin of the cavity but the field patterns are at an angle to that origin, maybe by as much as 45 degrees. The antenna center is offset from the big end by 1.35 inches and the central axis by the radius of the cavity minus 7 mm in the Y edge direction of the cavity. So the field pattern coordinate values detected by meep are a vector combination of the field patterns generated by the antenna.

To me the implication seems to be that patterns detected by meep will not coincide with the theorecal patterns except when the antenna is centered within the cavity.
Retired, working interesting problems

WarpTech

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Re: EM Drive Developments - related to space flight applications - Thread 3
« Reply #2304 on: 06/23/2015 04:40 AM »
Those dimensions

BIG DIAMETER = 0.27246 m
SMALL DIAMETER = 0.068115 m
LENGTH =  0.4890240258390259 m

have lots of natural frequencies around that range.  Here are just a few, for flat ends:

Mode     frequency (GHz)
TE011   1.73146
TE012   2.0553
TE013   2.3431

TM211  1.9874
TM212  2.40296
TM213  2.72512

TE111  0.965122
TE112  1.24641
TE113  1.50459

TM111 1.51277
TM112 1.89759
TM113 2.20088

Looking at TE111 and assuming field strength = color, you can actually see how the strength of the field pushing on 3-sides of the triangle is symmetrical and nearly identical. Indicating, there should NOT be any thrust due to this mode.
Todd

demofsky

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Re: EM Drive Developments - related to space flight applications - Thread 3
« Reply #2305 on: 06/23/2015 05:01 AM »

...

Good points. I worried about the pendulum effect that I've seen on other tests and the slow movement of other outside forces is a concern. I remember setting up anti-vibration tables in a lab and watching cars and trucks drive by a 100 foot away. Even when we would set up our semiconductor equipment in a lab with a concrete floor we could detect the bending movement of the floor and into our machines by someone walking next to it. Very small movements, but a issue when they were expecting submicron accuracies.

....

Thanks!  I completely forgot about external forces like trucks.  A relative of mine was a spectroscopist.  His lab was in the lowest sub basement and had special foundations.  Even so, he had to have additional dampening for his lasers.  So rather than spend money on very expensive air tables he used a couple of layers of inner tubes sandwiched between sheets of plywood!  Worked extremely well I was told!!

Can't wait to see what results you get!
« Last Edit: 06/23/2015 05:16 AM by demofsky »

WarpTech

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Re: EM Drive Developments - related to space flight applications - Thread 3
« Reply #2306 on: 06/23/2015 05:07 AM »
MOMENTUM ENHANCEMENT

I think I just solved the momentum enhancement problem, and learned something new in the process. I'm working on my DC analysis, since now I'm 99% convinced microwaves are not causing thrust. In the course of my day, I was trying to figure out how much momentum is carried away by a quantum of magnetic flux. Very interesting answer, probably best described quantum mechanically, though that is not how I came to this conclusion.

In a superconductor, the momentum of the cooper pair is given by; p = h/λ
A quantum of magnetic flux is given by: Φ=h/2e

Therefore, momentum/volt-sec = p/Φ = 2e/λ

In macroscopic terms, the momentum carried away by the magnetic flux, depends on the recoil momentum of the charge per unit length of the electrons flowing in the copper. This value is an intrinsic property of the copper based on the free electron density, which is only slightly altered by collisions, heat and relativistic effects (velocity).

So far, I have shown that due to the inductance gradient of the cone geometry, there is a force acting on the current and magnetic flux, pushing it toward the big end. I've also shown that the drift velocity at the small end is much larger than at the big end, so as the current is pushed toward the big end, it is losing momentum in the form of magnetic flux. The amount of momentum gained by the frustum will depend on the difference in drift velocity, the momentum stored as magnetic flux AND, on how much of it can escape.
Todd

aero

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Re: EM Drive Developments - related to space flight applications - Thread 3
« Reply #2307 on: 06/23/2015 05:08 AM »

The critical issue I've seen id getting power cables to the Drive without having to worry about the power cable causing issues. I have the power box under the fulcrum in a shielded cage. The power line from it goes up to connect to a point above the center of the beam. *see drawing and never touches the beam which could cause deflection.
Thoughts? Questions?

Shell

there will be 4 wires needed for magnetron, 2 bias and 2 filament. Make a liquid "wire splice" for the 4 wires. Basically 4 test tubes of conductive mercury. An electrode from power supply wire goes in at bottom of tube. Another electrode from fulcrum drops down into mercury. The mercury conducts the voltage regardless of the depth of the fulcrum side electrode, it simply swims in it. Depth of mercury and length of electrode should allow Moment arm displacement without breaking contact (fulcrum side electrode rising out of mercury).

A non scientific description of a near frictionless wire splice...hope I explained it well enough.
Very well indeed! I'll look into it. I think I have some old home thermostats that used mercury. I need to be very careful of it.

Shell

You might check with Mulleton. As I recall he bought some liquid metal  not involving mercury specially sold for completing electrical contacts on his DYI device. I don't know how far his project has progressed but I'm sure he could give you a name of the material and maybe a source contact.

I had a thought while taking out the trash that I'd like to share. How large is your garage? If you need the extra sensitive with your laser detecter system could you use a couple (or more pairs) of mirrors to reflect the beam across your garage so that any movement will be amplified by the extra distance the light beam travels. You might even be able to see vibration noise this way.

This also applies to rfmwguy's setup.
Retired, working interesting problems

demofsky

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Re: EM Drive Developments - related to space flight applications - Thread 3
« Reply #2308 on: 06/23/2015 05:16 AM »
Most likely there is an RFI problem with the scale.  I'm going to attempt to shield the scale with the unit suspended above it to prove that it is RFI.

I have to say that these are very intriguing results!  While we are all waiting to see if you can eliminate RFI interference on your scale as the cause for these results, I would like to point out a couple of notable things:

1). The performance with and without dielectrics reflects Shawyer's and Yang's experience.

2).  Much more interesting from my perspective are the declining lows in your first experiment with the dielectrics.  This is a very similar pattern to the Eagleworks tests With a dielectric insert.  It was speculated at the time that this might have been due to out gassing but I can't see that happening with a ceramic dielectric!!

So what the heck is happening with the dielectrics?

There is a more subtle pattern of declining lows without the dielectrics, but it is more pronounced with them present.

So either there is some type of ongoing electrical (electrostatic?) interference with the digital scale once the power is off, significant out gassing from somewhere, or we are looking some very interesting theoretical issues here folks - and evanescent waves are just not going to cut it...

Edit:  After checking the scale,  it is apparent that the unit is getting lighter and so we have to add ballooning to the possible effects, with the dielectrics thermal mass sustaining the effect.

Don't read too much into the overall declining slope.   It takes a while for the scale to fully stabilize after placing the unit on it.   The faster I start the test the steeper the slope is, usually.   I have learned to wait longer before starting as you can see from the later test #'s.

Keep in mind the "suspended" test is without any contact between the test unit and the scale.  There should be absolutely no force registered in this configuration.   The weight on the scale is from several ceramic flooring tiles used to simulate the weight of the unit. I did test with very little weight on the scale with the unit suspended above it and there was no change in weight indicated:

20150621-test-42-nod-up-suspended-paper.png

This indicates that the RFI induced error may be related to the dynamic correction system used to offset heavy loads.:

http://www.scalenet.com/and/gx/sensor.html

Also, the tests done in the "down" orientation show much less force, though still in the "weighs less" direction.  This may be due to the better RF sealing on the fixed end which is down in the "down" orientation.

One thing to bear in mind here is that the error may not be RF induced but rather Magnetically or Electrostatically.  We really don't know how EM drives couple to the external environment. That said, eliminating possible sources of interference would be very enlightening for everyone building one of these.

Just wrapping the scale with well grounded aluminum foil might be a quick and dirty solution for RF and electrostatic interference...

« Last Edit: 06/23/2015 06:05 AM by demofsky »

demofsky

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Re: EM Drive Developments - related to space flight applications - Thread 3
« Reply #2309 on: 06/23/2015 05:37 AM »
MOMENTUM ENHANCEMENT

I think I just solved the momentum enhancement problem, and learned something new in the process. I'm working on my DC analysis, since now I'm 99% convinced microwaves are not causing thrust. In the course of my day, I was trying to figure out how much momentum is carried away by a quantum of magnetic flux. Very interesting answer, probably best described quantum mechanically, though that is not how I came to this conclusion.

In a superconductor, the momentum of the cooper pair is given by; p = h/λ
A quantum of magnetic flux is given by: Φ=h/2e

Therefore, momentum/volt-sec = p/Φ = 2e/λ

In macroscopic terms, the momentum carried away by the magnetic flux, depends on the recoil momentum of the charge per unit length of the electrons flowing in the copper. This value is an intrinsic property of the copper based on the free electron density, which is only slightly altered by collisions, heat and relativistic effects (velocity).

So far, I have shown that due to the inductance gradient of the cone geometry, there is a force acting on the current and magnetic flux, pushing it toward the big end. I've also shown that the drift velocity at the small end is much larger than at the big end, so as the current is pushed toward the big end, it is losing momentum in the form of magnetic flux. The amount of momentum gained by the frustum will depend on the difference in drift velocity, the momentum stored as magnetic flux AND, on how much of it can escape.
Todd

WOW!!!  This is VERY interesting!!  When you say "AND, on how much of it can escape." are you referring to the magnetic flux that is storing the momentum?  If so what is the mechanism that it uses to escape in your view?  Thanks!

SeeShells

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Re: EM Drive Developments - related to space flight applications - Thread 3
« Reply #2310 on: 06/23/2015 05:47 AM »
MOMENTUM ENHANCEMENT

I think I just solved the momentum enhancement problem, and learned something new in the process. I'm working on my DC analysis, since now I'm 99% convinced microwaves are not causing thrust. In the course of my day, I was trying to figure out how much momentum is carried away by a quantum of magnetic flux. Very interesting answer, probably best described quantum mechanically, though that is not how I came to this conclusion.

In a superconductor, the momentum of the cooper pair is given by; p = h/λ
A quantum of magnetic flux is given by: Φ=h/2e

Therefore, momentum/volt-sec = p/Φ = 2e/λ

In macroscopic terms, the momentum carried away by the magnetic flux, depends on the recoil momentum of the charge per unit length of the electrons flowing in the copper. This value is an intrinsic property of the copper based on the free electron density, which is only slightly altered by collisions, heat and relativistic effects (velocity).

So far, I have shown that due to the inductance gradient of the cone geometry, there is a force acting on the current and magnetic flux, pushing it toward the big end. I've also shown that the drift velocity at the small end is much larger than at the big end, so as the current is pushed toward the big end, it is losing momentum in the form of magnetic flux. The amount of momentum gained by the frustum will depend on the difference in drift velocity, the momentum stored as magnetic flux AND, on how much of it can escape.
Todd
Any bearing? Too many things are clicking again and again.
<paste>"In view of the fact that the evanescent waves actually correspond to the near fields of electromagnetic sources, in this article, we shall show that the group velocities of electromagnetic near-fields can be superluminal, which may provide a heuristic interpretation for the superluminal behaviors reported in many experiments of evanescent wave propagation."

My question to you is how well can a evanescent wave from the cycling and moving near magnetic fields off the frustum couple to the QV? This has been bugging me and sorry if it's a silly question.

Shell

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Re: EM Drive Developments - related to space flight applications - Thread 3
« Reply #2311 on: 06/23/2015 05:52 AM »

You might check with Mulleton. As I recall he bought some liquid metal  not involving mercury specially sold for completing electrical contacts on his DYI device. I don't know how far his project has progressed but I'm sure he could give you a name of the material and maybe a source contact.

I had a thought while taking out the trash that I'd like to share. How large is your garage? If you need the extra sensitive with your laser detecter system could you use a couple (or more pairs) of mirrors to reflect the beam across your garage so that any movement will be amplified by the extra distance the light beam travels. You might even be able to see vibration noise this way.

This also applies to rfmwguy's setup.

It is a good idea. more angles and lengths to calculate, I hate crunching numbers but if need be I will hack away with a smile.

Shell

PS: Nite all. I've just too many things swirling between my ears.
« Last Edit: 06/23/2015 05:58 AM by SeeShells »

WarpTech

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Re: EM Drive Developments - related to space flight applications - Thread 3
« Reply #2312 on: 06/23/2015 06:05 AM »
MOMENTUM ENHANCEMENT

I think I just solved the momentum enhancement problem, and learned something new in the process. I'm working on my DC analysis, since now I'm 99% convinced microwaves are not causing thrust. In the course of my day, I was trying to figure out how much momentum is carried away by a quantum of magnetic flux. Very interesting answer, probably best described quantum mechanically, though that is not how I came to this conclusion.

In a superconductor, the momentum of the cooper pair is given by; p = h/λ
A quantum of magnetic flux is given by: Φ=h/2e

Therefore, momentum/volt-sec = p/Φ = 2e/λ

In macroscopic terms, the momentum carried away by the magnetic flux, depends on the recoil momentum of the charge per unit length of the electrons flowing in the copper. This value is an intrinsic property of the copper based on the free electron density, which is only slightly altered by collisions, heat and relativistic effects (velocity).

So far, I have shown that due to the inductance gradient of the cone geometry, there is a force acting on the current and magnetic flux, pushing it toward the big end. I've also shown that the drift velocity at the small end is much larger than at the big end, so as the current is pushed toward the big end, it is losing momentum in the form of magnetic flux. The amount of momentum gained by the frustum will depend on the difference in drift velocity, the momentum stored as magnetic flux AND, on how much of it can escape.
Todd

WOW!!!  This is VERY interesting!!  When you say "AND, on how much of it can escape." are you referring to the magnetic flux that is storing the momentum?  If so what is the mechanism that it uses to escape in your view?  Thanks!

Yes, but I'm still working on it. It's partially due to resistance of the copper. When there is a voltage drop, it means flux is escaping the loop. For DC it's no problem, but for microwaves, the only thing that might explain it would be excessive heat causing the skin effect to degrade. IMO, thrust is more likely due to the DC offset from the half-wave 60Hz rectification driving the magnetron, than it is from the microwaves.
Todd

aero

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Re: EM Drive Developments - related to space flight applications - Thread 3
« Reply #2313 on: 06/23/2015 06:12 AM »

You might check with Mulleton. As I recall he bought some liquid metal  not involving mercury specially sold for completing electrical contacts on his DYI device. I don't know how far his project has progressed but I'm sure he could give you a name of the material and maybe a source contact.

I had a thought while taking out the trash that I'd like to share. How large is your garage? If you need the extra sensitive with your laser detecter system could you use a couple (or more pairs) of mirrors to reflect the beam across your garage so that any movement will be amplified by the extra distance the light beam travels. You might even be able to see vibration noise this way.

This also applies to rfmwguy's setup.

It is a good idea. more angles and lengths to calculate, I hate crunching numbers but if need be I will hack away with a smile.

Shell

PS: Nite all. I've just too many things swirling between my ears.

Ah, don't worry about the calculations until you have some data to reduce. Just get all your mirrors aligned (and secured) then drop a few miligrams of weight on the end of the beam at the cavity location. Calibrate like rfmwguy showed in his video. The only problem I see is to keep the mirrors from vibrating excessively, and of course movement would really hose your results.
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aero

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Re: EM Drive Developments - related to space flight applications - Thread 3
« Reply #2314 on: 06/23/2015 06:22 AM »
MOMENTUM ENHANCEMENT

I think I just solved the momentum enhancement problem, and learned something new in the process. I'm working on my DC analysis, since now I'm 99% convinced microwaves are not causing thrust. In the course of my day, I was trying to figure out how much momentum is carried away by a quantum of magnetic flux. Very interesting answer, probably best described quantum mechanically, though that is not how I came to this conclusion.

In a superconductor, the momentum of the cooper pair is given by; p = h/λ
A quantum of magnetic flux is given by: Φ=h/2e

Therefore, momentum/volt-sec = p/Φ = 2e/λ

In macroscopic terms, the momentum carried away by the magnetic flux, depends on the recoil momentum of the charge per unit length of the electrons flowing in the copper. This value is an intrinsic property of the copper based on the free electron density, which is only slightly altered by collisions, heat and relativistic effects (velocity).

So far, I have shown that due to the inductance gradient of the cone geometry, there is a force acting on the current and magnetic flux, pushing it toward the big end. I've also shown that the drift velocity at the small end is much larger than at the big end, so as the current is pushed toward the big end, it is losing momentum in the form of magnetic flux. The amount of momentum gained by the frustum will depend on the difference in drift velocity, the momentum stored as magnetic flux AND, on how much of it can escape.
Todd

WOW!!!  This is VERY interesting!!  When you say "AND, on how much of it can escape." are you referring to the magnetic flux that is storing the momentum?  If so what is the mechanism that it uses to escape in your view?  Thanks!

Yes, but I'm still working on it. It's partially due to resistance of the copper. When there is a voltage drop, it means flux is escaping the loop. For DC it's no problem, but for microwaves, the only thing that might explain it would be excessive heat causing the skin effect to degrade. IMO, thrust is more likely due to the DC offset from the half-wave 60Hz rectification driving the magnetron, than it is from the microwaves.
Todd

That says thrust is proportional  to frequency. Laser cavities here we come. Or maybe just very high frequency driven magnatrons. The reason they switch at 60 Hz is because 60 Hz is at the wall socket but there isn't any good reason not to use a 400 Hz generator or go even much higher. Might need to re-design the magnatron but that's no biggie compared to the payoff, if the thruster works that way.
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demofsky

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Re: EM Drive Developments - related to space flight applications - Thread 3
« Reply #2315 on: 06/23/2015 06:36 AM »
MOMENTUM ENHANCEMENT

I think I just solved the momentum enhancement problem, and learned something new in the process. I'm working on my DC analysis, since now I'm 99% convinced microwaves are not causing thrust. In the course of my day, I was trying to figure out how much momentum is carried away by a quantum of magnetic flux. Very interesting answer, probably best described quantum mechanically, though that is not how I came to this conclusion.

In a superconductor, the momentum of the cooper pair is given by; p = h/λ
A quantum of magnetic flux is given by: Φ=h/2e

Therefore, momentum/volt-sec = p/Φ = 2e/λ

In macroscopic terms, the momentum carried away by the magnetic flux, depends on the recoil momentum of the charge per unit length of the electrons flowing in the copper. This value is an intrinsic property of the copper based on the free electron density, which is only slightly altered by collisions, heat and relativistic effects (velocity).

So far, I have shown that due to the inductance gradient of the cone geometry, there is a force acting on the current and magnetic flux, pushing it toward the big end. I've also shown that the drift velocity at the small end is much larger than at the big end, so as the current is pushed toward the big end, it is losing momentum in the form of magnetic flux. The amount of momentum gained by the frustum will depend on the difference in drift velocity, the momentum stored as magnetic flux AND, on how much of it can escape.
Todd

WOW!!!  This is VERY interesting!!  When you say "AND, on how much of it can escape." are you referring to the magnetic flux that is storing the momentum?  If so what is the mechanism that it uses to escape in your view?  Thanks!

Yes, but I'm still working on it. It's partially due to resistance of the copper. When there is a voltage drop, it means flux is escaping the loop. For DC it's no problem, but for microwaves, the only thing that might explain it would be excessive heat causing the skin effect to degrade. IMO, thrust is more likely due to the DC offset from the half-wave 60Hz rectification driving the magnetron, than it is from the microwaves.
Todd

That says thrust is proportional  to frequency. Laser cavities here we come. Or maybe just very high frequency driven magnatrons. The reason they switch at 60 Hz is because 60 Hz is at the wall socket but there isn't any good reason not to use a 400 Hz generator or go even much higher. Might need to re-design the magnatron but that's no biggie compared to the payoff, if the thruster works that way.

Does it have to be a magnetron?  Would a simple RF source switched on/off 400+Hz work just as well??

aero

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Re: EM Drive Developments - related to space flight applications - Thread 3
« Reply #2316 on: 06/23/2015 06:45 AM »
Would a simple switched RF source work as well? Don't know.
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demofsky

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Re: EM Drive Developments - related to space flight applications - Thread 3
« Reply #2317 on: 06/23/2015 06:48 AM »
Would a simple switched RF source work as well? Don't know.

Todd, what are your thoughts?  Should be easy enough to test experimentally given the large number of simple RF source experiments that are coming on line...
« Last Edit: 06/23/2015 06:51 AM by demofsky »

TheTraveller

Re: EM Drive Developments - related to space flight applications - Thread 3
« Reply #2318 on: 06/23/2015 07:44 AM »
An email to Dr. White head, Eagleworks, JSC, NASA:

Quote
Hi Dr. White,

I'm an active member of the NSF EMDrive discussion forum and of the Reddit EMDrive group and an engineer by training.

On both forums your Appendix A titled

"Analysis  of  Conservation of  Energy for Interplanetary Space  Missions using Electric  Propulsion"

http://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/20140013174.pdf

has been claimed to be in error, being

1) The calculations for the start-final KE analysis is negative but is shown as positive.

2) The analysis fails to use the Oberth effect on the KE of the ships fuel.

Your comments are most welcome as possible CofE violation for long term thrusting spacecraft needs to be understood, especially if applicable to non propellantless drive technology.

I would also like to further understand this statement of yours:

"When this situation  occurs,  in  order  to  ensure  that  the  input  energy  is equal  to  the  change  in  kinetic  energy,  the  thrust  to  power performance  will  have  to  decrease  over  time."

How will this happen? How will the ship know when to stop obeying A = F/M and start reducing force generation to not break CofE? What will happen if the ship continually accelerates?

I actively support your work at Eagleworks and believe those that say your Q Thruster / EMDrive can't work as claimed because then CofE will be violated are incorrect.

Hopefully your reply will help others to understand apparent CofE violation with propellantless thrusters is not the show stopper they think it is.

Best regards

I didn't mention the NSF members
deltaMass,
WarpTech,
frobnicat

who appatently have claimed Dr. White is wrong.

Do hope they come forward once Dr. White responds and take up their claims directly with Dr. White.

Getting the CofE issue clearly resolved one way or the other is so important so we can move forward and leave an incorrect assumption (one or the orher) behind.

When I initially had issues with Roger Shawyer, I didn't call him out in a public forum, making comments behind his back that he was incorrect. I gave him the courtesy of answering my concerns, which he did.
« Last Edit: 06/23/2015 07:47 AM by TheTraveller »
It Is Time For The EmDrive To Come Out Of The Shadows

deltaMass

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Re: EM Drive Developments - related to space flight applications - Thread 3
« Reply #2319 on: 06/23/2015 07:47 AM »

The critical issue I've seen id getting power cables to the Drive without having to worry about the power cable causing issues. I have the power box under the fulcrum in a shielded cage. The power line from it goes up to connect to a point above the center of the beam. *see drawing and never touches the beam which could cause deflection.
Thoughts? Questions?

Shell

there will be 4 wires needed for magnetron, 2 bias and 2 filament. Make a liquid "wire splice" for the 4 wires. Basically 4 test tubes of conductive mercury. An electrode from power supply wire goes in at bottom of tube. Another electrode from fulcrum drops down into mercury. The mercury conducts the voltage regardless of the depth of the fulcrum side electrode, it simply swims in it. Depth of mercury and length of electrode should allow Moment arm displacement without breaking contact (fulcrum side electrode rising out of mercury).

A non scientific description of a near frictionless wire splice...hope I explained it well enough.
Very well indeed! I'll look into it. I think I have some old home thermostats that used mercury. I need to be very careful of it.

Shell
The liquid connection of choice here is something called Galinstan. Do check it out. It's far safer than mercury.
« Last Edit: 06/23/2015 07:48 AM by deltaMass »

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