EM Drive Developments - related to space flight applications - Thread 8

[LowerAtmosphere]

A gentle reminder to the readers that gain medium and em drive architecture has been discussed at length in previous posts and threads. IIRC, Ammonia and noble gases seem most useful as a gain medium due to their mostly inert and coolant properties. To reduce noise, i.e. circular rehashing of old arguments, I strongly strongly recommend all potential commenters to completely read the previous threads.

Error sources such as Lorentz force, electrostriction, thermal jets, thermal buckling, mechanical resonance, magnetic field interaction, incorrect damping, wind, moisture, evanescent wave effects, evaporation, ionization, and much much more has been exhaustively discussed. Help progress the research not mire this thread in philosophical or copenhagen interpretation/CoM/CoE discussions. For example, help further develop Warptech's nascent thrust equation.

[Rodal]

Concerning patent applications claiming the use of Argon to stimulate emission at ~24 GHz of the EM Drive,
besides it being obvious (from the invention and applicaiton of the Maser decades ago), such an idea was published in these threads by me a long time ago, and such an idea was periodically discussed in these threads. 

It is a basic tenet of patents (whereby the Government awards a monopoly to somebody for a finite period of time in exchange for fully disclosing a new invention) that no patents can be validly awarded and enforced for anything that was already described and published in the open literature.

See the doctrine of prior art:

https://en.wikipedia.org/wiki/Prior_art

and defensive publication:

https://en.wikipedia.org/wiki/Defensive_publication

and the case that clarified non-obviousness:

https://en.wikipedia.org/wiki/Graham_v._John_Deere_Co.

===> Beware of people taking any ideas previously described and published in these NSF threads or other publications (including all the information that NASA Eagleworks, Shawyer, Tajmar and numerous EM Drive aficionados have made available), applying for a patent based on those ideas and then attempting to sell such patent applications to buyers that may be unaware of Patent Law. If interested please get advice from an Intellectual Property Lawyer.

[Star One]

Why does every article out there keeps calling it "NASA's em drive"  when  NASA didn't even want to touch it with a barge pole for almost 2 decades?  They and everyone in the science world kept looking down their noses at it and calling it crackpot  and fringe science?
Now NASA thinks it can claim it as theirs? Really?

It is the media who emphasize the prefix "NASA's" to EmDrive. I do not think NASA wants its name to be associated with EmDrive. On the opposite to your impression, mine is that NASA will make announcement to keep itself away from EmDrive soon.

I suspect you're probably right considering how conservative NASA likes to be with their science announcements in general.

[Star-Drive]

Have any of the tests on EMDrive been performed with maintaining a vacuum inside of the frustrum?

This is an excellent question. If the EW test under vacuum did indeed vent the frustum to its external environment, there must have been a vent allowing it to do so, whether intentional or not. Did this vent exist? If it did, what was the effect of this hole on the Q of the frustum? If it did not, what was the effect of the frustum expansion as its internal 1 atmosphere was exposed to external vacuum outside the frustum? Could the phase locked loop deal with this probably severe cavity distortion? If it could do so, could it maintain phase lock under mode shift? If so, what are the use of the results?

The results of these experiments should NOT be thrust versus frequency, thrust versus Q, thrust versus mode. They should be thrust versus input power based upon ONE of the above. Expected result versus controlled input. To date, absolutely no-one has done this.

As many others on this forum have suggested (including myself), a kilowatt is a kilowatt is a kilowatt. A resistive heater within the frustum dissipating the same energy would go a long way to answering quite a few of the thermal issues.

Would be intriguing to see how a vacuum inside the frustrum would affect performance considering that such a drive could easily operate in a vacuum in application(since it's intended use is in space). 

Would also be intriguing to see if it would be possible to utilize(and filter if necessary) the already existing AMPLE background radiation in space to power this. Tapping that would be like running a cruise liner in a sea of diesel fuel.

All:

The EW copper frustum was radially vented along the entire perimeter of both the big OD and small OD ends of the frustum, so any vented gas's momentum would be cancelled out.  Thus all the copper frustum tests run in an ambient vacuum also had near the same vacuum level in the frustum itself.  I also made sure that all venting was completed before running any tests and since it took hours to reach the desired vacuum levels of less than ~5x10^-5 Torr, all venting activities were long gone before testing started.

Best,

Thanks for that clarification. Was reviewing the wiki data and it looks as though the team was using the same frequency as when testing in an ambient atmosphere. However, you may then need to recallibrate the frequency for optimal performance in a vacuum. This is because the wavelength is longer in a vacuum then air.

http://www.rpi.edu/dept/phys/Dept2/APPhys1/optics/optics/node7.html

Reading back through my response, it may not have come across as intended. That's what I get for writing responses at 2AM. :-)

Want to say that I admire the work you guys do. There are a lot of variables involved and just as many critics.

My post better worded: Did your team have a chance to try other frequencies while testing in a vacuum? Or did you find that 1.9371 GHz was the optimum frequency?

Reference: http://emdrive.wiki/Experimental_Results

Therealjjj77:

See the attached pdf file with my documented Kentucky Windage air-to-vacuum tuning issue defined.  My makeshift solution for the EW in-vacuum test runs was to add a ~0.6 MHz frequency shift to all my in-air Vector Network Analyzer (VNA) resonant frequency data and hoped that the PLL would pull the VCO to the correct in-vacuum frequency.  That worked most of the time, but...

Best, Paul M.

[meems]

the tiresomely cynical and mocking youtuber ThunderFoot thinks emdrive thrust is due to a 'radiometer' effect : a hot plate tranfers KE to incident air particles that act as propellant.

I have to admit I didn't think of this effect.

If the emdrive has an asymmetric radiometer effect then it will produce thrust in air, but much less in a vacuum.

How does emdrive in-air to in-vacuum results compare?
Has this effect been accounted for and excluded?
Can you refute thunderfoot's claim from existing results?

[toloverufan]

Can you refute thunderfoot's claim from existing results?

https://www.youtube.com/watch?v=jCAqDA8IfR4?t=22m6s

He goes on to finish that bit with a correction. The team actually got the same signature with and without an atmosphere. Really the whole video was a tepid jab rather than a full on takedown.

[meberbs]

the tiresomely cynical and mocking youtuber ThunderFoot thinks emdrive thrust is due to a 'radiometer' effect : a hot plate tranfers KE to incident air particles that act as propellant.

I have to admit I didn't think of this effect.

If the emdrive has an asymmetric radiometer effect then it will produce thrust in air, but much less in a vacuum.

How does emdrive in-air to in-vacuum results compare?
Has this effect been accounted for and excluded?
Can you refute thunderfoot's claim from existing results?

https://www.youtube.com/watch?v=jCAqDA8IfR4?t=22m6s

I assume he had been talking about the Crooke's radiometer effect (I haven't watched the video). This is something I had considered as a possible contributing factor.

That effect actually works best in partial vacuum. I don't have time to double check right now, but I had checked before, and I think the vacuum level in the NASA tests is on the low end of where that effect remains significant. I am not sure if the geometry of the emDrive compared to a normal radiometer could affect the magnitude of this or what pressure range it can be observed at.

[TheTraveller]

On the opposite to your impression, mine is that NASA will make announcement to keep itself away from EmDrive soon.

I agree with that assessment as otherwise they would have renewed Paul's contract and properly funded EW to build a next generation 100mN thruster that can exceed Ion drive efficiency. But then maybe that would upset a lot of other electric propulsion projects NASA is funding?

BTW what is your take on the stronger and reversed thrust direction when Paul tested the same frustum, torsion pendulum position and wiring position but without the dielectric? Surely removing the dielectric could not reverse and increase the strength of any Lorentz force?

https://forum.nasaspaceflight.com/index.php?topic=40959.msg1614369#msg1614369

If you note on the images, Paul did measure the Lorentz force (which didn't change) and used it to calc the resultant no Lorentz force values, being 2.0uN/W with dielectric big to small and 3.85uN/W small to big no dielectric. Note the direction of the force arrows in the 2 images.

To me this strongly says the forces that Paul measured are not the result of Lorentz forces, which for sure are there, were measured and the raw force values were adjusted for the Lorentz background forces.

[meberbs]

On the opposite to your impression, mine is that NASA will make announcement to keep itself away from EmDrive soon.

I agree with that assessment as otherwise they would have renewed Paul's contract and properly funded EW to build a next generation 100mN thruster that can exceed Ion drive efficiency. But then maybe that would upset a lot of other electric propulsion projects NASA is funding?

I know you think that somehow the emDrive is 100% proven, but to most scientists it still looks like experimental errors are the most likely cause of any positive results. Any lack of funding is because they still haven't produced a signal that stands out from the noise (what EW measured was smaller than the thermal effects, and could easily be due to a different thermal effect with a different time constant.) Given the lack of conclusive results and the remaining high probability that this is still just experimental error, it would make sense that funding would go to technologies that have a reasonable chance at success due to their better chance of success and not because of some petty politics.

[PotomacNeuron]

On the opposite to your impression, mine is that NASA will make announcement to keep itself away from EmDrive soon.

I agree with that assessment as otherwise they would have renewed Paul's contract and properly funded EW to build a next generation 100mN thruster that can exceed Ion drive efficiency. But then maybe that would upset a lot of other electric propulsion projects NASA is funding?

BTW what is your take on the stronger and reversed thrust direction when Paul tested the same frustum, torsion pendulum position and wiring position but without the dielectric? Surely removing the dielectric could not reverse and increase the strength of any Lorentz force?

https://forum.nasaspaceflight.com/index.php?topic=40959.msg1614369#msg1614369

If you note on the images, Paul did measure the Lorentz force (which didn't change) and used it to calc the resultant no Lorentz force values, being 2.0uN/W with dielectric big to small and 3.85uN/W small to big no dielectric. Note the direction of the force arrows in the 2 images.

To me this strongly says the forces that Paul measured are not the result of Lorentz forces, which for sure are there, were measured and the raw force values were adjusted for the Lorentz background forces.

The question is how to build a 100mN thruster when the validity of 100uN result is still in question.

[oyzw]

On the opposite to your impression, mine is that NASA will make announcement to keep itself away from EmDrive soon.

I agree with that assessment as otherwise they would have renewed Paul's contract and properly funded EW to build a next generation 100mN thruster that can exceed Ion drive efficiency. But then maybe that would upset a lot of other electric propulsion projects NASA is funding?

BTW what is your take on the stronger and reversed thrust direction when Paul tested the same frustum, torsion pendulum position and wiring position but without the dielectric? Surely removing the dielectric could not reverse and increase the strength of any Lorentz force?

https://forum.nasaspaceflight.com/index.php?topic=40959.msg1614369#msg1614369

If you note on the images, Paul did measure the Lorentz force (which didn't change) and used it to calc the resultant no Lorentz force values, being 2.0uN/W with dielectric big to small and 3.85uN/W small to big no dielectric. Note the direction of the force arrows in the 2 images.

To me this strongly says the forces that Paul measured are not the result of Lorentz forces, which for sure are there, were measured and the raw force values were adjusted for the Lorentz background forces.

The question is how to build a 100mN thruster when the validity of 100uN result is still in question.

When you are still arguing, I have been anxiously waiting for the space EMDRIVE test data in our country.

[Chrochne]

On the opposite to your impression, mine is that NASA will make announcement to keep itself away from EmDrive soon.

I agree with that assessment as otherwise they would have renewed Paul's contract and properly funded EW to build a next generation 100mN thruster that can exceed Ion drive efficiency. But then maybe that would upset a lot of other electric propulsion projects NASA is funding?

BTW what is your take on the stronger and reversed thrust direction when Paul tested the same frustum, torsion pendulum position and wiring position but without the dielectric? Surely removing the dielectric could not reverse and increase the strength of any Lorentz force?

https://forum.nasaspaceflight.com/index.php?topic=40959.msg1614369#msg1614369

If you note on the images, Paul did measure the Lorentz force (which didn't change) and used it to calc the resultant no Lorentz force values, being 2.0uN/W with dielectric big to small and 3.85uN/W small to big no dielectric. Note the direction of the force arrows in the 2 images.

To me this strongly says the forces that Paul measured are not the result of Lorentz forces, which for sure are there, were measured and the raw force values were adjusted for the Lorentz background forces.

The question is how to build a 100mN thruster when the validity of 100uN result is still in question.

When you are still arguing, I have been anxiously waiting for the space EMDRIVE test data in our country.

Thats what I call a bombshell.  Can you give us more details? Who? When? Is it in space already? Please share! Is China really that far from the rest of the world?

[Star One]

On the opposite to your impression, mine is that NASA will make announcement to keep itself away from EmDrive soon.

I agree with that assessment as otherwise they would have renewed Paul's contract and properly funded EW to build a next generation 100mN thruster that can exceed Ion drive efficiency. But then maybe that would upset a lot of other electric propulsion projects NASA is funding?

I know you think that somehow the emDrive is 100% proven, but to most scientists it still looks like experimental errors are the most likely cause of any positive results. Any lack of funding is because they still haven't produced a signal that stands out from the noise (what EW measured was smaller than the thermal effects, and could easily be due to a different thermal effect with a different time constant.) Given the lack of conclusive results and the remaining high probability that this is still just experimental error, it would make sense that funding would go to technologies that have a reasonable chance at success due to their better chance of success and not because of some petty politics.

The only problem is if it is ever proven they end up looking like they've missed out on important technology and people will question why you looked at this and then dismissed it.

[rfmwguy]

On the opposite to your impression, mine is that NASA will make announcement to keep itself away from EmDrive soon.

I agree with that assessment as otherwise they would have renewed Paul's contract and properly funded EW to build a next generation 100mN thruster that can exceed Ion drive efficiency. But then maybe that would upset a lot of other electric propulsion projects NASA is funding?

I know you think that somehow the emDrive is 100% proven, but to most scientists it still looks like experimental errors are the most likely cause of any positive results. Any lack of funding is because they still haven't produced a signal that stands out from the noise (what EW measured was smaller than the thermal effects, and could easily be due to a different thermal effect with a different time constant.) Given the lack of conclusive results and the remaining high probability that this is still just experimental error, it would make sense that funding would go to technologies that have a reasonable chance at success due to their better chance of success and not because of some petty politics.

The only problem is if it is ever proven they end up looking like they've missed out on important technology and people will question why you looked at this and then dismissed it.

The emdrive argument has switched from concept to experimentation which is where it should have been. Dismissing a concept without experiments is a safe approach and many take this route. Unfortunately for them, the experiment has yielded results which need more replication. A conceptual position against ew and diyers experimental results now forces them to move beyond words. They must now conduct their own experiments to prove their position that it's unquantified systematics or common errors. Without their own evidence, all they have are words. I do not see antagonists having the time, skill or interest is backing up their beliefs with their own data. IOW, I wouldn't give them much attention or concern.

[CorvusCorax]

Reading the NASA paper published last month, one of the main issues in verifying thrust effects is that thermal effects still have a significant effect on frustrum movement, even if its just through shifts in the COG, which are in the same order of magnitude (although following different dynamics) than the actual thrust force.

A suggested improvement is to modify the arrangement to minimize COG changes caused by thermal expansion/shrinkage.

Wouldn't it make sense to instead make sure to enter a "thermal steady state"? As such I would propose to run a EM-drive prototype continuously powered during an experiment, and start measurements only once power components have reached steady state operating temperatures, where heat production and heat dissipation from heat sinks and cavity itself are at equalibrium

Modifying the thrust vector would then not be done by turning the main HF power source on/off, but by altering more subtle parameters, such as resonance frequency tuning. (AKA deliberately detune the system to eliminate the thrust force)

All HF components would continuously operate at the select power output throughout the duration of the experiment. As such the force, and how it changes based on small differences in the cavity resonance and phase shift properties could be studied without any significant thermal expansion or shrinkage affecting measurement results. The entire system could be calibrated for this thermal steady state to achieve higher resolution.

Of course for that, the HF components would have to be rated to operate continuously for several hours or longer.

(This might have been discussed before. I haven't had the chance to read through all 150 pages of this as well as all 7 previous threads. If so, feel free to moderate this post.)

[TheTraveller]

On the opposite to your impression, mine is that NASA will make announcement to keep itself away from EmDrive soon.

I agree with that assessment as otherwise they would have renewed Paul's contract and properly funded EW to build a next generation 100mN thruster that can exceed Ion drive efficiency. But then maybe that would upset a lot of other electric propulsion projects NASA is funding?

BTW what is your take on the stronger and reversed thrust direction when Paul tested the same frustum, torsion pendulum position and wiring position but without the dielectric? Surely removing the dielectric could not reverse and increase the strength of any Lorentz force?

https://forum.nasaspaceflight.com/index.php?topic=40959.msg1614369#msg1614369

If you note on the images, Paul did measure the Lorentz force (which didn't change) and used it to calc the resultant no Lorentz force values, being 2.0uN/W with dielectric big to small and 3.85uN/W small to big no dielectric. Note the direction of the force arrows in the 2 images.

To me this strongly says the forces that Paul measured are not the result of Lorentz forces, which for sure are there, were measured and the raw force values were adjusted for the Lorentz background forces.

The question is how to build a 100mN thruster when the validity of 100uN result is still in question.

When you are still arguing, I have been anxiously waiting for the space EMDRIVE test data in our country.

My info is the Chinese EmDrive space test is a non cryo EmDrive designed and tested on Earth by Prof Yang and a new Chinese engineering team.

So those who wrote and posted Prof Yang had retired were posting not correct data.

[TheTraveller]

On the opposite to your impression, mine is that NASA will make announcement to keep itself away from EmDrive soon.

I agree with that assessment as otherwise they would have renewed Paul's contract and properly funded EW to build a next generation 100mN thruster that can exceed Ion drive efficiency. But then maybe that would upset a lot of other electric propulsion projects NASA is funding?

BTW what is your take on the stronger and reversed thrust direction when Paul tested the same frustum, torsion pendulum position and wiring position but without the dielectric? Surely removing the dielectric could not reverse and increase the strength of any Lorentz force?

https://forum.nasaspaceflight.com/index.php?topic=40959.msg1614369#msg1614369

If you note on the images, Paul did measure the Lorentz force (which didn't change) and used it to calc the resultant no Lorentz force values, being 2.0uN/W with dielectric big to small and 3.85uN/W small to big no dielectric. Note the direction of the force arrows in the 2 images.

To me this strongly says the forces that Paul measured are not the result of Lorentz forces, which for sure are there, were measured and the raw force values were adjusted for the Lorentz background forces.

The question is how to build a 100mN thruster when the validity of 100uN result is still in question.

Sorry to say but the reverse force direction with no dielectric totally destroys Lorentz force being behind the effect.

Doing 100mN/kW or 10,000N/kW is just EnDrive Enginerring.

See you in LEO or way beyond.

[Willem Staal]

i heard rumours that the Chinese already launced a experimental em-drive into space.

They still waiting for results. 

[TheTraveller]

On the opposite to your impression, mine is that NASA will make announcement to keep itself away from EmDrive soon.

I agree with that assessment as otherwise they would have renewed Paul's contract and properly funded EW to build a next generation 100mN thruster that can exceed Ion drive efficiency. But then maybe that would upset a lot of other electric propulsion projects NASA is funding?

I know you think that somehow the emDrive is 100% proven, but to most scientists it still looks like experimental errors are the most likely cause of any positive results. Any lack of funding is because they still haven't produced a signal that stands out from the noise (what EW measured was smaller than the thermal effects, and could easily be due to a different thermal effect with a different time constant.) Given the lack of conclusive results and the remaining high probability that this is still just experimental error, it would make sense that funding would go to technologies that have a reasonable chance at success due to their better chance of success and not because of some petty politics.

Your opinion is incorrect as it has always been.

Would suggest you spend intellect time on theory development instead of wasted time on stating EmDrive can't work because of X.

EmDrive works today as well as it worked in 1989 as per Roger's 1st patent.

[TheTraveller]

i heard rumours that the Chinese already launced a experimental em-drive into space.

They still waiting for results. 

My understanding is the Chinese experimental satellite has many experiments to conduct,  the non cryo EmDrive from Prof Yang's new team is one of the experiments.