EM Drive

[kunkmiester]

Just out of curiosity...is it reasonably possible that both EM Drive & Mach Thruster drive will turn out to work? Or are their "theories" of operation in some way incompatible?

My understanding is that the proposed theory for the workings of the EmDrive involves rejecting wave-particle duality. In other words, it claims photons occupy a specific location in space at any given time and that something else (unspecified) is the source of strangeness.

The Mach Effect is based on Mach's Principle, which, put vaguely, is "mass out there influences inertia". So there doesn't seem to be much common ground.

Dr. Jean-Philippe Montillet has suggested that if the EmDrive works, it's because it is functioning as a capacitor and that the Mach Effect applies. Dr. Rodal of Heidi Fearn's MEGA team talks about that here: http://forum.nasaspaceflight.com/index.php?topic=40959.msg1588165#msg1588165.

Anyhow, I'm not the best person to ask. Maybe someone else can provide a better explanation.

She mentioned Mach- Lorentz effects, hasn't it been established that Mach effects require bulk acceleration, which Lorentz forces accelerating just the ions can't do?

Reminds me I need to post about some Mach thruster questions I have.

[williatw]

Breakthrough Discuss 2018 – Day Two


Sonny White's talk starts at about 03:40:00 in the tape.


https://www.youtube.com/watch?v=3GiN-tWAV_k


More information here:

Sonny White at Eagleworks scaling EMdrive experiments to 400 watts





Breakthrough Discuss is an academic conference focused on the question of life in the Universe. More information on the Breakthrough Initiatives is available at https://breakthroughinitiatives.org.

Sonny White has a new paper Spacedrives and Conservation Laws

Raymond Sedwick
University of Maryland, College Park, Maryland 20740
Associate Professor, Department of Aerospace Engineering. Associate Fellow AIAA.

Harold White
NASA Johnson Space Center, Houston, Texas 77058
Advanced Propulsion Theme Lead and Principal Investigator, Eagleworks Laboratories, Mailing Code EP4. Member AIAA.

In the video:
Harold White looks at Pilot Wave Theory

His theory is that Acoustic resonances in the quantum vacuum are directly responsible for atomic structure
Applying a time-varying electromagnetic field using simulation and experimentation
He then has force predictions














Lawrence Krauss argues with White on the quantum physics principles. at 4:00 hours into the video.
Robert Zubrin then follows up about White using 100 times more thrust per kilowatt in the proposed mission beyond what they have measured.

https://www.nextbigfuture.com/2018/05/s ... nts-145119


From the comments section:

Bamboleo 
8 hour(s) ago
400W?!
It took him 7 years to scale to 400W?!
What's the next step after this? 410W? hahaha

This guy is a modern day snake oil salesman.

We shall see...(hopefully not).

[williatw]

The SpaceDrive Project – First Results on EMDrive and Mach-Effect Thrusters

Tajmar is finding more magnetic interaction from cables. He is not conclusively saying that is all that is happening with EMdrive or Mach Effect but he thinks it is a significant error source for such tiny thrust measurements.

Propellantless propulsion is believed to be the best option for interstellar travel. However, photon rockets or solar sails have thrusts so low that maybe only nano-scaled spacecraft may reach the next star within our lifetime using very high-power laser beams. Following into the footsteps of earlier breakthrough propulsion programs, we are investigating different concepts based on non-classical/revolutionary propulsion ideas that claim to be at least an order of magnitude more efficient in producing thrust compared to photon rockets. Our intention is to develop an excellent research infrastructure to test new ideas and measure thrusts and/or artefacts with high confidence to determine if a concept works and if it does how to scale it up. At present, we are focusing on two possible revolutionary concepts: The EMDrive and the Mach-Effect Thruster. The first concept uses microwaves in a truncated cone-shaped cavity that is claimed to produce thrust. Although it is not clear on which theoretical basis this can work, several experimental tests have been reported in the literature, which warrants a closer examination. The second concept is believed to generate mass fluctuations in a piezo-crystal stack that creates non-zero time-averaged thrusts. Here we are reporting first results of our improved thrust balance as well as EMDrive and Mach-Effect thruster models. Special attention is given to the investigation and identification of error sources that cause false thrust signals. Our results show that the magnetic interaction from not sufficiently shielded cables or thrusters are a major factor that needs to be taken into account for proper µN thrust measurements for these type of devices.

2017 Presentation from Tajmar

SSI APW 2017: 04. Dr. Martin Tajmar

https://www.youtube.com/watch?v=36Hpgxb9MdU



https://www.nextbigfuture.com/2018/05/t ... sters.html

[paperburn1]

EM drive just got peer reviews and it does not look good.
Unfortunately, a new round of research out of Germany is casting some big doubts on those early results. In a new research paper the team argues that not only does the engine not actually produce any thrust, but that earlier tests may have erroneously detected thrust due to “electromagnetic interaction” between the engine and Earth’s own magnetic field. Oops!

but if it works in orbit that still could be useful.

[Aero]

EM drive just got peer reviews and it does not look good.
Unfortunately, a new round of research out of Germany is casting some big doubts on those early results. In a new research paper the team argues that not only does the engine not actually produce any thrust, but that earlier tests may have erroneously detected thrust due to “electromagnetic interaction” between the engine and Earth’s own magnetic field. Oops!

but if it works in orbit that still could be useful.

but if it works in orbit that still could be useful.

That statement rings true to me. How would one go about designing a thruster based on this interaction with Earth's magnetic field? Some compact propellantless device that could counter drag on a satellite orbiting at 100 - 200 km altitude would be very useful indeed.

[ScottL]

That statement rings true to me. How would one go about designing a thruster based on this interaction with Earth's magnetic field? Some compact propellantless device that could counter drag on a satellite orbiting at 100 - 200 km altitude would be very useful indeed.

Here is my simplified down answer: There are two important things to know to answer that question. First, the Earth's magnetic field is actually weak relatively speaking. Second, magnetic fields lose strength rapidly over distance (inverse-square law). With those 2 bits of information in mind, you would not have enough magnetic field to react against to overcome gravity and even if you were able to overcome it at a specific orbit, all like-devices would be locked around that orbit roughly, never to be used for solar exploration or interstellar exploration.

[paperburn1]

All that seems to ring true as well.

[williatw]

All that seems to ring true as well.

Not to take the subject away from flywheels...but

Sonny White at Eagleworks scaling EMdrive experiments to 400 watts

Anyone here still holding out any hope that Sonny White will succeed in pulling a rabbit out of his hat and proving EmDrive is valid? Understand that Tajmar hasn't exactly killed it yet just seems to be saying you can't rule out some kind of interference causing the apparent "thrust" results? Maybe White's stronger power will help, but personally I think until someone orbits a satellite with a truly autonomous system and switches it on to see what happens the pro-EmDrive people (White) are just blowing smoke. Same with the Mach drive folks. Can't cost that much to put up a small sat containing the apparatus.

[ScottL]

Anyone here still holding out any hope that Sonny White will succeed in pulling a rabbit out of his hat and proving EmDrive is valid? Understand that Tajmar hasn't exactly killed it yet just seems to be saying you can't rule out some kind of interference causing the apparent "thrust" results? Maybe White's stronger power will help, but personally I think until someone orbits a satellite with a truly autonomous system and switches it on to see what happens the pro-EmDrive people (White) are just blowing smoke. Same with the Mach drive folks. Can't cost that much to put up a small sat containing the apparatus.

My problem with White has always been that he appropriates someone else's experiment/research then attempts to attribute any results claimed to his QVF model. If you look at White's EmDrive work, his initial attempts found the same measurement for both their device as well as their control (which is pretty much what happen with Tajmar). Instead of trying to explain why that could be, he doubled down, building another device and retooling his theory to fit unobserved (to that point) thrust. The lone published paper by White on the EmDrive lacked proper error analysis and to further muddy the waters, was published to a propulsion journal (target audience is engineers) with a poor peer review process instead of a well known/respected physics journal (target audience is phycisists). Even before the EmDrive, he was looking at Woodward's work and trying to shoehorn it into his QVF model. The pursuit to further our understanding can be a noble one, however; the actions taken within that pursuit ultimately decide.

[ScottL]

US Navy EM Drive group reporting negative result.
https://forum.nasaspaceflight.com/index.php?topic=45824.msg1855304#msg1855304

Monomorphic and others reporting negative results
https://forum.nasaspaceflight.com/index.php?topic=45824.msg1854984#msg1854984

Appears it is finally coming to rest.

[TDPerk]

US Navy EM Drive group reporting negative result.
https://forum.nasaspaceflight.com/index.php?topic=45824.msg1855304#msg1855304

Monomorphic and others reporting negative results
https://forum.nasaspaceflight.com/index.php?topic=45824.msg1854984#msg1854984

Appears it is finally coming to rest.

Hopefully this will result in more energy going to Woodward's MET concept.

[williatw]

Hopefully this will result in more energy going to Woodward's MET concept.

Not according to your posted link:

As for the mach effect thruster, it is also not doing well. Several high level physics heavy presentations, including one by Dr. Rodal, that make the claim that the mach effect thruster cannot work as Woodward describes and is likely a self-interaction effect. Tajmar's group thinks it doesn't work and will report tomorrow. Then in my presentation I showed how Woodward's thrust signature can be generated in a simulation of the device using first principles and simple mechanics - and how everything equals out to zero at the end. I was also able to build a crude 3 DOF device that produced the same "thrust" signature.

So bad news all around...not very happy about this.

[kunkmiester]

We will have to see what Woodward does to address it.

It might be a decent shot to try a different design, like the magnetic oscillator I've mentioned. While there is magnetic issues to be dealt with the cap stack could be on an air bearing or something and thus have no space for Dean drive effects in the piezo stack.

My google fu has been short on finding me maximum possible frequencies it could run at, and all I can remember from a community college class is it should be more than a few KHz.

[TDPerk]

Hopefully this will result in more energy going to Woodward's MET concept.

Not according to your posted link:

As for the mach effect thruster, it is also not doing well. Several high level physics heavy presentations, including one by Dr. Rodal, that make the claim that the mach effect thruster cannot work as Woodward describes and is likely a self-interaction effect. Tajmar's group thinks it doesn't work and will report tomorrow. Then in my presentation I showed how Woodward's thrust signature can be generated in a simulation of the device using first principles and simple mechanics - and how everything equals out to zero at the end. I was also able to build a crude 3 DOF device that produced the same "thrust" signature.

So bad news all around...not very happy about this.

I know Tajmar and I believe Rodal's work has already been refuted (shown not to be able to support the conclusions they come to) by Dr. Woodward.

[TDPerk]

Hopefully this will result in more energy going to Woodward's MET concept.

Not according to your posted link:

As for the mach effect thruster, it is also not doing well. Several high level physics heavy presentations, including one by Dr. Rodal, that make the claim that the mach effect thruster cannot work as Woodward describes and is likely a self-interaction effect. Tajmar's group thinks it doesn't work and will report tomorrow. Then in my presentation I showed how Woodward's thrust signature can be generated in a simulation of the device using first principles and simple mechanics - and how everything equals out to zero at the end. I was also able to build a crude 3 DOF device that produced the same "thrust" signature.

So bad news all around...not very happy about this.

I know Tajmar and I believe Rodal's recent work has already been refuted (shown not to be able to support the conclusions they come to) by Dr. Woodward.