Author Topic: EM Drive Developments - related to space flight applications - Thread 3  (Read 1872640 times)

Offline rfmwguy

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As history marches on we tend to forget who discovered the wheel or tamed the first horse or made cats and dogs .... Then I wondered why there is little thrust in a vacuum, could it be no particles of air for the evanescent wave action to act on?...
Yes, and let's wonder why Shawyer whose first patent on this was in the late 1980's has never reported on thrust from the EM Drive in vacuum ?  And why Yang with all her University resources (which is very well equipped as the data shows) has never reported on experiments done in vacuum either?  And why didn't Boeing continue the contract work with SPR on the Flight Thruster?  Could it be because of the lower thrust in vacuum as reported by Paul March and soon to be reported in the AIAA by Prof. Tajmar from TU Dresden, Germany?

Also think about this: if air or another gas is required, how is it required? because if it is required as a propellant (with air ions leaking to the outside) this is no longer a propellant-less propulsion, is it.  And if it is using surrounding air, it cannot be used in space (just like air-breathing jet engines cannot be used in space).

Also recall that all the EM Drive tests have been run for relatively short periods of time up to now.

Many things to wonder about :)
I've pondered over this for some time but I kept on coming back to it. I do think there is a way to take a real advantage of this effect in a vacuum if it proves out to be true. Last hot tub idea.
Shell
Good reading this AM has me leaning towards centered small base injection of the monopole because of what Shell said about the variety of insertion points yielding apparent results. NSF-1701 will be similar to EW except a monopole rather than a coupling loop.

Other variations frow EW:
1) Copper mesh sidewalls
2) 10.2 inch length
3) 900 W @2.45 GHz

Thats probably enough variance...too much and I could be too far off previous experiments. Once I do some powered-up static testing of the magnetron's core temperature, I'll know how much to push the signal duration.


Offline SeeShells

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Ok here is a fiber optic cone shape with just light traveling through it grab a cell of trillions of atoms and shove it along? If there wasn't the viscous medium how fast would the cells accelerate?


No, MHO this EMDrive IMHO is just starting to show what it really can do. Not warp space or bend time or increase mass (not too much yet) but provide a way to increase real thrust.

Shell

Offline deltaMass

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Let's examine the possibility of lift-off from Earth's surface with an EmDrive. To be able to do this, the thrust must exceed the weight, so we require

k  > g / PMR

where g~=10 and PMR is the power to mass ratio in W/Kg. k as usual is in N/W.

Now look here
https://en.wikipedia.org/wiki/Power-to-weight_ratio
The top candidate is the General Atomics HV capacitor: 6.8*106 W/Kg.
http://www.ga.com/series-cmx-self-healing-energy-storage-capacitors

This sets the constraint

k > 1.5*10-6  N/W

Note that lift-off refers to the all-up mass, so we must arrange matters such that the total mass is predominantly that of the power source.

Note also that the above is wildly optimistic - just dig in on the cap specs a little and you'll see why.
You'll get a little hop that is powered for about 300 us :)
« Last Edit: 07/17/2015 05:38 PM by deltaMass »

Offline Rodal

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Let's examine the possibility of lift-off from Earth's surface with an EmDrive. To be able to do this, the thrust must exceed the weight, so we require

k  > g / PMR

where g~=10 and PMR is the power to mass ratio in W/Kg. k as usual is in N/W.

Now look here
https://en.wikipedia.org/wiki/Power-to-weight_ratio
The top candidate is the General Atomics HV capacitor: 6.8*106 W/Kg.

This sets the constraint

k > 1.5*10-6  N/W

Note that lift-off refers to the all-up mass, so we must arrange matters such that the total mass is predominantly that of the power source.
Although I agree that the calculation is elucidating in its own right, and I thank you for doing it, and I realize you know this, but as a remark to the general reader reading this, NASA Eagleworks is not presently proposing to use this technology for lift-off from the Earth's surface, or even from Mars (although it would be very feasible for lift off from Phobos or Deimos), but its purpose is to be used in space like ion rockets are deployed into space by conventional chemical propulsion.  The proposed advantage (if the EM Drive were to work in vacuum as proposed but not proven) is thrust/InputPower for continuous acceleration like an ion rocket, the thrust itself being too small for Earth's lift-off.
« Last Edit: 07/17/2015 05:25 PM by Rodal »

Offline mwvp

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NSF-1701 update...good news for meepers, I have not yet placed the magnetron into the frustum. I will this weekend, so here's ur chance to suggest placement. Suggest wavelength placement and locale...near big, near small or centered. I was planning on 1/2 wavelength from small end...doesn't matter to me. Julian moved from large end to center...meepers can respond.

Sorry I haven't done any simulations yet, installed MPD and ran through an example. Only required the FT package, so if you've got Meep, MPD isn't another big install.

As for placement, and speaking as someone who hasn't worked with waveguides but has seen quite a bit of RF lit, I would say probe or link/loop coupling for the desired mode at its 50 ohm point.

If one were to take the E and B field plots from Meep and divide the E/B and plot the zones, you'd know where to put an appropriate impedance probe, oriented to excite the field in question.

I have on my hypothetical todo list to go to a forum where experienced engineers hang, and get expert advice. Probably my best suggestion. Go find RF/microwave trade journals, like RF Design, Microwaves & RF, RF Cafe et., go to their forums and ask an expert.

And tell us what you find. Or wait till I get around to it (probably a bad idea).

Offline mittelhauser

According to present data, testing the EMDrive with input powers at or above 1 MW is necessary to reach a thrust that can actually be experienced without doubt of measurement errors.

Achieving a thrust level high enough to lift an object would (as done by Goddard with chemical rockets) finally convince people to adequately fund R&D in this area.

Let us gather enough supporters to send an E-Mail to Mythbusters.

They definitely have the money and means to use a Gyrotron, Klystron or a similar powerful microwave source and build a simple truncated cone microwave resonator to see whether they can achieve a level of thrust high enough to convince people to fund adequate R&D in this area.

100Ws will generate more than enough Force, if applied to a 20kg load on a 1.5 mtr wide rotary table, to generate continual acceleration for many minutes, going from 0 rpm to over 120 rpm or 2 rps. All cordless, totally self contained.

Can then repeat that process, over and over again, until the 24v 24AH SLA batteries are drained.

There will be no doubt, after such a demo that the EMDrive works as Shawyer has claimed since 2002.

Traveller, I truly appreciate your optimism.  However, I am also very tired of hearing about what your test WILL do.  The fact that you have no doubts actually makes me more concerned (not less). 

PLEASE just go prove me wrong and come back with actual results.  Then I will give your posts more credibility (especially if others can replicate as you keep insisting they'll be able to).  Until then, I am tired of hearing predictions stated with unreasonable confidence. 

Offline TheTraveller

Let's examine the possibility of lift-off from Earth's surface with an EmDrive. To be able to do this, the thrust must exceed the weight, so we require

k  > g / PMR

where g~=10 and PMR is the power to mass ratio in W/Kg. k as usual is in N/W.

Now look here
https://en.wikipedia.org/wiki/Power-to-weight_ratio
The top candidate is the General Atomics HV capacitor: 6.8*106 W/Kg.

This sets the constraint

k > 1.5*10-6  N/W

Note that lift-off refers to the all-up mass, so we must arrange matters such that the total mass is predominantly that of the power source.
Although I agree that the calculation is elucidating in its own right, and I thank you for doing it, and I realize you know this, but as a remark to the general reader reading this, NASA Eagleworks is not presently proposing to use this technology for lift-off from the Earth's surface, or even from Mars (although it would be very feasible for lift off from Phobos or Deimos), but its purpose is to be used in space like ion rockets are deployed into space by conventional chemical propulsion.  The proposed advantage (if the EM Drive were to work in vacuum as proposed but not proven) is thrust/InputPower for continuous acceleration like an ion rocket, the thrust itself being too small for Earth's lift-off.

Assuming a 1N/kW EMDrive could power wise scale to 100N/100kW and using 20 of these on a 90t crewed ship could do at 0.0023g:

LEO to Pluto low orbit (40AUs), 12.4 months.
LEO to Mars low orbit, at min 60mkm, 37 days.
LEO to Mars low orbit, at avg 225mkm, 78 days.

So with just 100N/100kW EMDrives, the entire solar system would be open to human exploration and colonisation. Would still need propellant based rockets to Taxis from low orbit >< the surface.
« Last Edit: 07/17/2015 05:48 PM by TheTraveller »
"As for me, I am tormented with an everlasting itch for things remote. I love to sail forbidden seas.
Herman Melville, Moby Dick

Offline deltaMass

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Let's examine the possibility of lift-off from Earth's surface with an EmDrive. To be able to do this, the thrust must exceed the weight, so we require

k  > g / PMR

where g~=10 and PMR is the power to mass ratio in W/Kg. k as usual is in N/W.

Now look here
https://en.wikipedia.org/wiki/Power-to-weight_ratio
The top candidate is the General Atomics HV capacitor: 6.8*106 W/Kg.

This sets the constraint

k > 1.5*10-6  N/W

Note that lift-off refers to the all-up mass, so we must arrange matters such that the total mass is predominantly that of the power source.
Although I agree that the calculation is elucidating in its own right, and I thank you for doing it, and I realize you know this, but as a remark to the general reader reading this, NASA Eagleworks is not presently proposing to use this technology for lift-off from the Earth's surface, or even from Mars (although it would be very feasible for lift off from Phobos or Deimos), but its purpose is to be used in space like ion rockets are deployed into space by conventional chemical propulsion.  The proposed advantage (if the EM Drive were to work in vacuum as proposed but not proven) is thrust/InputPower for continuous acceleration like an ion rocket, the thrust itself being too small for Earth's lift-off.

Assuming a 1N/kW EMDrive could power wise scale to 100N/100kW and using 20 of these on a 90t crewed ship could do at 0.0023g:

LEO to Pluto low orbit (40AUs), 12.4 months.
LEO to Mars low orbit, at min 60mkm, 37 days.
LEO to Mars low orbit, at avg 225mkm, 78 days.

So with just 100N/100kW EMDrives, the entire solar system would be open to human exploration and colonisation. Would still need propellant based rockets to Taxis from low orbit >< the surface.
How do you propose to garner your required 2 MW?

Offline rfmwguy

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NSF-1701 update...good news for meepers, I have not yet placed the magnetron into the frustum. I will this weekend, so here's ur chance to suggest placement. Suggest wavelength placement and locale...near big, near small or centered. I was planning on 1/2 wavelength from small end...doesn't matter to me. Julian moved from large end to center...meepers can respond.

Sorry I haven't done any simulations yet, installed MPD and ran through an example. Only required the FT package, so if you've got Meep, MPD isn't another big install.

As for placement, and speaking as someone who hasn't worked with waveguides but has seen quite a bit of RF lit, I would say probe or link/loop coupling for the desired mode at its 50 ohm point.

If one were to take the E and B field plots from Meep and divide the E/B and plot the zones, you'd know where to put an appropriate impedance probe, oriented to excite the field in question.

I have on my hypothetical todo list to go to a forum where experienced engineers hang, and get expert advice. Probably my best suggestion. Go find RF/microwave trade journals, like RF Design, Microwaves & RF, RF Cafe et., go to their forums and ask an expert.

And tell us what you find. Or wait till I get around to it (probably a bad idea).
Here's an article I had published in MW&RF: http://mwrf.com/commercial/assemble-high-power-attenuator-systems

Offline Ricvil

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Just a thought.  ;D

It is just a ray trace realization of a resonant cavity with metamaterial inside ( n= -1; negative refraction index)
The result cavity shape is a tappered conical ( in 3D by revolution symmetry).
I1,I2,I3 and I4 are the images of point P (no diffraction idealization).
The metallic mirrors are to reflect back any ray from P point ( focal point inside metamaterial).
My doubt... what will be the result force in resonance?
« Last Edit: 07/17/2015 06:19 PM by Ricvil »

Offline deltaMass

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Here's a design challenge: Can a mechanical device be built that rotates an EmDrive at 1 Km/s at Earth's surface?

Offline SeeShells

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Let's examine the possibility of lift-off from Earth's surface with an EmDrive. To be able to do this, the thrust must exceed the weight, so we require

k  > g / PMR

where g~=10 and PMR is the power to mass ratio in W/Kg. k as usual is in N/W.

Now look here
https://en.wikipedia.org/wiki/Power-to-weight_ratio
The top candidate is the General Atomics HV capacitor: 6.8*106 W/Kg.
http://www.ga.com/series-cmx-self-healing-energy-storage-capacitors

This sets the constraint

k > 1.5*10-6  N/W

Note that lift-off refers to the all-up mass, so we must arrange matters such that the total mass is predominantly that of the power source.

Note also that the above is wildly optimistic - just dig in on the cap specs a little and you'll see why.
You'll get a little hop that is powered for about 300 us :)
For the current designs yes if this is indeed what this is. Don't forget there was something happening in some vacuum chamber this this doesn't explain.

Offline TheTraveller

According to present data, testing the EMDrive with input powers at or above 1 MW is necessary to reach a thrust that can actually be experienced without doubt of measurement errors.

Achieving a thrust level high enough to lift an object would (as done by Goddard with chemical rockets) finally convince people to adequately fund R&D in this area.

Let us gather enough supporters to send an E-Mail to Mythbusters.

They definitely have the money and means to use a Gyrotron, Klystron or a similar powerful microwave source and build a simple truncated cone microwave resonator to see whether they can achieve a level of thrust high enough to convince people to fund adequate R&D in this area.

100Ws will generate more than enough Force, if applied to a 20kg load on a 1.5 mtr wide rotary table, to generate continual acceleration for many minutes, going from 0 rpm to over 120 rpm or 2 rps. All cordless, totally self contained.

Can then repeat that process, over and over again, until the 24v 24AH SLA batteries are drained.

There will be no doubt, after such a demo that the EMDrive works as Shawyer has claimed since 2002.

Traveller, I truly appreciate your optimism.  However, I am also very tired of hearing about what your test WILL do.  The fact that you have no doubts actually makes me more concerned (not less). 

PLEASE just go prove me wrong and come back with actual results.  Then I will give your posts more credibility (especially if others can replicate as you keep insisting they'll be able to).  Until then, I am tired of hearing predictions stated with unreasonable confidence.

What I'm replication was done in 2006. The Demonstrator EMDrive and rotary test rig were funded by a UK gov grant. SPR didn't get final payment until the UK Dept of Defense appointed, 7 UK aerospace companies and other academic experts signed off on the validity of the test results.

Plus I have a direct link to the guy who built the Demonstrator EMDrive and the 10 inch Loadpoint D03099 air bearing based rotary test rig. Any suggestions that this air bearing could self rotate with a 100kg load are rubbish. Anybody making such claims has not done their research.

So yes I have NO doubt I can replicate the narrow band Flight Thruster, it's control & monitoring system and a rotary test rig with a 20kg load and get good acceleration and rotation, while collecting quality data.
« Last Edit: 07/17/2015 06:23 PM by TheTraveller »
"As for me, I am tormented with an everlasting itch for things remote. I love to sail forbidden seas.
Herman Melville, Moby Dick

Offline mwvp

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Here's an article I had published in MW&RF: http://mwrf.com/commercial/assemble-high-power-attenuator-systems

Cool. The highest power systems I've worked on, cellular and an tactical satellite, were only a few hundred watts (cooking in the microwave oven notwithstanding). The fusor-guy, Coulter, I referenced mentioned his (IIRC) RG-58 getting a bit warm at the current-nodes along the coax. Wonder if I could get away with a 30 second run with a meter of RG-178, 500 W @ 2.4 GHz? Probably not

Offline rfmwguy

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Here's an article I had published in MW&RF: http://mwrf.com/commercial/assemble-high-power-attenuator-systems

Cool. The highest power systems I've worked on, cellular and an tactical satellite, were only a few hundred watts (cooking in the microwave oven notwithstanding). The fusor-guy, Coulter, I referenced mentioned his (IIRC) RG-58 getting a bit warm at the current-nodes along the coax. Wonder if I could get away with a 30 second run with a meter of RG-178, 500 W @ 2.4 GHz? Probably not
Got my feet wet into 10kW and 1 GHz in the broadcast marketplace. Never saw a cavity launch into space tho ;^)

Offline mwvp

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Just a thought.  ;D

It is just a ray trace realization of a resonant cavity with metamaterial inside ( n= -1; negative refraction index)
The result cavity shape is a tappered conical ( in 3D by revolution symmetry).
I1,I2,I3 and I4 are the images of point P (no diffraction idealization).
The metallic mirrors are to reflect back any ray from P point ( focal point inside metamaterial).
My doubt... what will be the result force in resonance?

Sounds like a job for MPD & Meep. I was thinking that the atomic dipoles of the metamaterial/dielectric will be in motion and subtract from the vacuum-mode reaction against the frustrum, but that doesn't seem to matter in fiber-optic gyros. I would think with using a gaseous or liquid masing/lasing medium the forces will go into merely stirring things up.

After absorbing Jayne's paper on  ghost modes in microwave waveguides, photonic crystals and Schrodinger-waves in semiconductors, and in light of apparent exhaust-less thrust being measured in phonon-dispersive Peltier devices, I can imagine a number of ways ratcheting could be created by energy, other than microwaves in a frustrum.

Since some of the most efficient generators of EM energy are magnetrons and klystrons, why not just fire an electron beam down a tapered-impedance (dispersive) slow-wave waveguide, so as to integrate the microwave generator and thruster into a single assembly? But again, there would be the reaction against the electron beam.

Offline SeeShells

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According to present data, testing the EMDrive with input powers at or above 1 MW is necessary to reach a thrust that can actually be experienced without doubt of measurement errors.

Achieving a thrust level high enough to lift an object would (as done by Goddard with chemical rockets) finally convince people to adequately fund R&D in this area.

Let us gather enough supporters to send an E-Mail to Mythbusters.

They definitely have the money and means to use a Gyrotron, Klystron or a similar powerful microwave source and build a simple truncated cone microwave resonator to see whether they can achieve a level of thrust high enough to convince people to fund adequate R&D in this area.

100Ws will generate more than enough Force, if applied to a 20kg load on a 1.5 mtr wide rotary table, to generate continual acceleration for many minutes, going from 0 rpm to over 120 rpm or 2 rps. All cordless, totally self contained.

Can then repeat that process, over and over again, until the 24v 24AH SLA batteries are drained.

There will be no doubt, after such a demo that the EMDrive works as Shawyer has claimed since 2002.

Traveller, I truly appreciate your optimism.  However, I am also very tired of hearing about what your test WILL do.  The fact that you have no doubts actually makes me more concerned (not less). 

PLEASE just go prove me wrong and come back with actual results.  Then I will give your posts more credibility (especially if others can replicate as you keep insisting they'll be able to).  Until then, I am tired of hearing predictions stated with unreasonable confidence.

What I'm replication was done in 2006. The Demonstrator EMDrive and rotary test rig were funded by a UK gov grant. SPR didn't get final payment until the UK Dept of Defense appointed, 7 UK aerospace companies and other academic experts signed off on the validity of the test results.

Plus I have a direct link to the guy who built the Demonstrator EMDrive and the 10 inch Loadpoint D03099 air bearing based rotary test rig. Any suggestions that this air bearing could self rotate with a 100kg load are rubbish. Anybody making such claims has not done their research.

So yes I have NO doubt I can replicate the narrow band Flight Thruster, it's control & monitoring system and a rotary test rig with a 20kg load and get good acceleration and rotation, while collecting quality data.
How bout that I know and have met and worked on air bearings, powered and not, with my design projects? How about working with the Load Point engineers and the VP of engineering back when the were called WestWind and even after they changed?

I'm quite aware of who they are.

Shell

shell


Offline Rodal

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How bout that I know and have met and worked on air bearings, powered and not, with my design projects? How about working with the Load Point engineers and the VP of engineering back when the were called WestWind and even after they changed?

I'm quite aware of who they are.

Shell
Rest assured, Shell that we know you as a real person with a real name, while the person that rampantly charged  <<rubbish. Anybody making such claims has not done their research....>> did so under cover of an anonymous monicker. 
« Last Edit: 07/17/2015 07:34 PM by Rodal »

Offline SeeShells

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Ok look at this. How many orders of thrust do were see above Ion or Light propulsion? This is an effect that can change most everything if used correctly and still satisfy all the critical poo from the Com and CoE advocates and even Maxwell is happy.

We still have a high thrust system.

Yes certainly above a flaslight photon rocket.  Compared to VASIMIR at 8500 a photon rocket thrust/InputPower, the numbers reported by March in vacuum were 25 times lower: 330 times a photon rocket.  Prof. Tajmar will report significantly lower numbers.   So, if NASA can increase the numbers reported by March for vacuum by a factor of 30, (30 mN/kW) we would have something better than VASIMIR, and hopefully not  using propellant (VASIMIR uses argon).
It seems to propel organic molecules quite well in the fibre optics, but driving it with a NY Steak strapped to it isn't my idea of getting better thrust. I'm reading and digging and I think I'm quite close to a answer that might work.

Shell


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Just a thought.  ;D

It is just a ray trace realization of a resonant cavity with metamaterial inside ( n= -1; negative refraction index)
The result cavity shape is a tappered conical ( in 3D by revolution symmetry).
I1,I2,I3 and I4 are the images of point P (no diffraction idealization).
The metallic mirrors are to reflect back any ray from P point ( focal point inside metamaterial).
My doubt... what will be the result force in resonance?

Metamaterial at W frequency was already realized several years ago. But in most cases it consists of flat metallic structures based on a lot of equal layers. These metallic structures are local compositions of inductors and capacitors. The direction of the wave propagation is not equal for all impact angles. The refractive angle is only for a few degree in phase to create a resulting negative permittivity and/or permeability. ;)
Sure, it may be possible to create 3D structures to do the job for any angle but i've never seen till now. :-\
If anybody is able to create a metamaterial with large BW in the optically and the IR what works for any angle the military will be interested for sure!   :o ;D ;D

BTW dielectric inlays at the small diameter are almost equal to a more complex geometry in this area, it is not longer a simple frustum caused by a grater possible wave number in that region (for all the different modes this leads to different resulting geometry, sine/cosine of the E field with boundary conditions, diameter and length with respect to the z-axis). The higher the Epsilon the bigger the resulting equal geometry without dielectrica. ::)
« Last Edit: 07/17/2015 09:46 PM by X_RaY »

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