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#1180
by
TheUberOverLord
on 03 Jan, 2016 14:27
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The black hole in DIY data is more an issue of being able to record credible data, before time or money run out.
For EW, it is almost certain that they had a great deal more that has not been shared, than what has been. Even in peer reviewed and published work, you will seldom see all of the data from everything that was tried.
We all want to see and know everything about every step.., including how long Shell sits impatiently twiddling her thumbs, while waiting for some delivery she has no control over.
The truth is this is not interactive reality TV. What is discussed here does have some impact on both the DIY builds and testing and likely even EW, but we will never see everything that happen behind the scenes.
On the issue of vacuum and resonance, I am sure that it does and it has been mentioned in past posts, even to the point that in EWs early vacuum tests it was not possible to fine tune the resonance while in vacuum. I don't that it is true, but I would be surprised if that were not one of the things EW has, at least attempted to resolve.
The way a frustum is being constructed in most of these early attempts, it would be impractical to test where the air pressure was not the same inside and out.., without as mentioned by someone else the thing blowing up like a balloon. Shell did mention she could gas fill her build with a gas that would help eliminate arcing. I assume that would still be to the same pressure inside and out.
ADD: The speed of light in vacuum vs air over the distances inside a frustum..? I don't think they can be thought of as significant. Someone mentioned way back that even red shifting would be insignificant, where the distances and accelerations involved are comcerned.
Still think there was poor test planning on steps by EW.
Simply the issue of vacuum and EM Drive cavity resonance changes with no tests using normal atmospheric content and pressure with the same EM Drive created the "Black Hole" of missing data. That missing data would not be as bad as it is if the same EM Drive was tested using normal atmospheric content and pressure or by still using a vacuum with a testing step included. That maintained the cavities normal atmospheric content and pressure. If one was too complicated to do. Surely the other could have been done.
That also may have at least provided some benchmark of what the same EM Drive build could do in normal atmospheric content and pressure might have resolved.
It might have even allowed others to be able to better calculate resonance changes in a vacuum using the same EM Drive cavity as well.
I think your statement that because of the short length of a EM Drive cavity. That the change of such a short cavity being or not being in a vacuum, can't be thought of as significant. Is an incorrect one when it comes to resonance changes and harmonics of EM Drive cavities.
Dielectric Strength of Air vs. Vacuumhttps://en.wikipedia.org/wiki/Dielectric_strength#Breakdown_field_strengthDon
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#1181
by
OnlyMe
on 03 Jan, 2016 15:23
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... I think your statement that because of the short length of a EM Drive cavity. That the change of such a short cavity being or not being in a vacuum, can't be thought of as significant. Is an incorrect one when it comes to resonance changes and harmonics of EM Drive cavities.
Don
My comments about lengths were only how they might affect resonance due to speed of light changes and red shifting, air vs vacuum.
I believe that resonance is altering the boundary conditions inside the frustum. That is something meep does not account for. I am not even sure any of the modeling software available can. Mostly, it seems to me that, the frustum itself is treated as though its conductivity etc. are static or normal and only the harmonics of the resonant microwaves change....
The speed of light changes equally in all directions, when comparing air vs vacuum.
Boundary conditions change not just with resonance (my supposition), but also with the presence of air or vacuum... The frustum walls in one case are already interacting with air.., in the other vacuum, which depending on just what the quantum vacuum is, may or may not be affecting the frustum wall boundary conditions.... Different boundary conditions, under different conditions... And then add resonant microwaves and how they interact with and alter the boundary conditions of the frustum walls....
The point is that any change in the speed of light, air vs vacuum, would affect all walls of the frustum equally.., and even if there were a difference, the distances involved would put that so far below measurable that, only by evaluating the situation within the context of QFT/QED/SED, which would be required to understand possible changes to boundary conditions anyway, would those changes/effects be practically relative.
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#1182
by
Prunesquallor
on 03 Jan, 2016 15:38
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The black hole in DIY data is more an issue of being able to record credible data, before time or money run out.
For EW, it is almost certain that they had a great deal more that has not been shared, than what has been. Even in peer reviewed and published work, you will seldom see all of the data from everything that was tried.
We all want to see and know everything about every step.., including how long Shell sits impatiently twiddling her thumbs, while waiting for some delivery she has no control over.
The truth is this is not interactive reality TV. What is discussed here does have some impact on both the DIY builds and testing and likely even EW, but we will never see everything that happen behind the scenes.
On the issue of vacuum and resonance, I am sure that it does and it has been mentioned in past posts, even to the point that in EWs early vacuum tests it was not possible to fine tune the resonance while in vacuum. I don't that it is true, but I would be surprised if that were not one of the things EW has, at least attempted to resolve.
The way a frustum is being constructed in most of these early attempts, it would be impractical to test where the air pressure was not the same inside and out.., without as mentioned by someone else the thing blowing up like a balloon. Shell did mention she could gas fill her build with a gas that would help eliminate arcing. I assume that would still be to the same pressure inside and out.
ADD: The speed of light in vacuum vs air over the distances inside a frustum..? I don't think they can be thought of as significant. Someone mentioned way back that even red shifting would be insignificant, where the distances and accelerations involved are comcerned.
Still think there was poor test planning on steps by EW.
Simply the issue of vacuum and EM Drive cavity resonance changes with no tests using normal atmospheric content and pressure with the same EM Drive created the "Black Hole" of missing data. That missing data would not be as bad as it is if the same EM Drive was tested using normal atmospheric content and pressure or by still using a vacuum with a testing step included. That maintained the cavities normal atmospheric content and pressure. If one was too complicated to do. Surely the other could have been done.
That also may have at least provided some benchmark of what the same EM Drive build could do in normal atmospheric content and pressure might have resolved.
It might have even allowed others to be able to better calculate resonance changes in a vacuum using the same EM Drive cavity as well.
I think your statement that because of the short length of a EM Drive cavity. That the change of such a short cavity being or not being in a vacuum, can't be thought of as significant. Is an incorrect one when it comes to resonance changes and harmonics of EM Drive cavities.
Dielectric Strength of Air vs. Vacuum
https://en.wikipedia.org/wiki/Dielectric_strength#Breakdown_field_strength
Don
If someone tests a pressurized frustum in a vac chamber, they will forever be chasing forces caused by random venting, gas jets, skin flexure, etc. It seems to me that's the LAST thing you want to have happening if you are trying to establish if an anomalous thrust actually exists.
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#1183
by
TheUberOverLord
on 03 Jan, 2016 15:43
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... I think your statement that because of the short length of a EM Drive cavity. That the change of such a short cavity being or not being in a vacuum, can't be thought of as significant. Is an incorrect one when it comes to resonance changes and harmonics of EM Drive cavities.
Don
My comments about lengths were only how they might affect resonance due to speed of light changes and red shifting, air vs vacuum.
I believe that resonance is altering the boundary conditions inside the frustum. That is something meep does not account for. I am not even sure any of the modeling software available can. Mostly, it seems to me that, the frustum itself is treated as though its conductivity etc. are static or normal and only the harmonics of the resonant microwaves change....
The speed of light changes equally in all directions, when comparing air vs vacuum.
Boundary conditions change not just with resonance (my supposition), but also with the presence of air or vacuum... The frustum walls in one case are already interacting with air.., in the other vacuum, which depending on just what the quantum vacuum is, may or may not be affecting the frustum wall boundary conditions.... Different boundary conditions, under different conditions... And then add resonant microwaves and how they interact with and alter the boundary conditions of the frustum walls....
The point is that any change in the speed of light, air vs vacuum, would affect all walls of the frustum equally.., and even if there were a difference, the distances involved would put that so far below measurable that, only by evaluating the situation within the context of QFT/QED/SED, which would be required to understand possible changes to boundary conditions anyway, would those changes/effects be practically relative.
Point being that even EW admits that replacing a EM Drives cavity of normal atmospheric content and pressure with a vacuum. Does changes resonance and harmonics of a EM Drive cavities. Which may or may not have anything to do with thrust.
The cause, is the increase in the speed that the microwaves ("Light") can travel in the cavity. Since the cavity dimensions themselves have not changed. So, like it or not. There is a measurable cause and effect which has not yet been quantified, when a EM Drive is used inside a vacuum vs. outside a vacuum.
Don
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#1184
by
TheUberOverLord
on 03 Jan, 2016 15:46
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The black hole in DIY data is more an issue of being able to record credible data, before time or money run out.
For EW, it is almost certain that they had a great deal more that has not been shared, than what has been. Even in peer reviewed and published work, you will seldom see all of the data from everything that was tried.
We all want to see and know everything about every step.., including how long Shell sits impatiently twiddling her thumbs, while waiting for some delivery she has no control over.
The truth is this is not interactive reality TV. What is discussed here does have some impact on both the DIY builds and testing and likely even EW, but we will never see everything that happen behind the scenes.
On the issue of vacuum and resonance, I am sure that it does and it has been mentioned in past posts, even to the point that in EWs early vacuum tests it was not possible to fine tune the resonance while in vacuum. I don't that it is true, but I would be surprised if that were not one of the things EW has, at least attempted to resolve.
The way a frustum is being constructed in most of these early attempts, it would be impractical to test where the air pressure was not the same inside and out.., without as mentioned by someone else the thing blowing up like a balloon. Shell did mention she could gas fill her build with a gas that would help eliminate arcing. I assume that would still be to the same pressure inside and out.
ADD: The speed of light in vacuum vs air over the distances inside a frustum..? I don't think they can be thought of as significant. Someone mentioned way back that even red shifting would be insignificant, where the distances and accelerations involved are comcerned.
Still think there was poor test planning on steps by EW.
Simply the issue of vacuum and EM Drive cavity resonance changes with no tests using normal atmospheric content and pressure with the same EM Drive created the "Black Hole" of missing data. That missing data would not be as bad as it is if the same EM Drive was tested using normal atmospheric content and pressure or by still using a vacuum with a testing step included. That maintained the cavities normal atmospheric content and pressure. If one was too complicated to do. Surely the other could have been done.
That also may have at least provided some benchmark of what the same EM Drive build could do in normal atmospheric content and pressure might have resolved.
It might have even allowed others to be able to better calculate resonance changes in a vacuum using the same EM Drive cavity as well.
I think your statement that because of the short length of a EM Drive cavity. That the change of such a short cavity being or not being in a vacuum, can't be thought of as significant. Is an incorrect one when it comes to resonance changes and harmonics of EM Drive cavities.
Dielectric Strength of Air vs. Vacuum
https://en.wikipedia.org/wiki/Dielectric_strength#Breakdown_field_strength
Don
If someone tests a pressurized frustum in a vac chamber, they will forever be chasing forces caused by random venting, gas jets, skin flexure, etc. It seems to me that's the LAST thing you want to have happening if you are trying to establish if an anomalous thrust actually exists.
That does not mean one can't test the same EM Drive outside of the vacuum to get test data on what that same EM Drive can do in a normal atmosphere. Just saying if one can't do one. One should still do the other vs. only do one test with the EM Drive in a vacuum including the cavity contents being replaced by a vacuum.
After all. What if the same EM Drive would also not have produced any measurable thrust outside of a vacuum. What have you proved? Maybe your EM Drive design was poor or bad.
Don
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#1185
by
OnlyMe
on 03 Jan, 2016 15:51
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(...)
If someone tests a pressurized frustum in a vac chamber, they will forever be chasing forces caused by random venting, gas jets, skin flexure, etc. It seems to me that's the LAST thing you want to have happening if you are trying to establish if an anomalous thrust actually exists.
It would certainly require a far more robust design, than has so far been the subject of testing.
That said, until we have more data, about just where EW went with their experiments after going dark, we don't even know if the initial results we have heard about, were systemic or die to loss of atmosphere inside the frustum.
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#1186
by
aero
on 03 Jan, 2016 15:53
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You are aware, are you not, that most EW tests were in atmosphere. All tests reported in the "Anomalous Thrust..." paper were in a vacuum chamber with the door closed but not pumped down, (that is, at atmospheric pressure). The reason given was time schedule pressure and the 2-3 days needed to draw down a good vacuum.Only later (2015) did they actually pump the vacuum chamber down to test in moderate vacuum.
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#1187
by
TheUberOverLord
on 03 Jan, 2016 16:05
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You are aware, are you not, that most EW tests were in atmosphere. All tests reported in the "Anomalous Thrust..." paper were in a vacuum chamber with the door closed but not pumped down, (that is, at atmospheric pressure). The reason given was time schedule pressure and the 2-3 days needed to draw down a good vacuum.Only later (2015) did they actually pump the vacuum chamber down to test in moderate vacuum.
Yes.
But, as you know there has been a major focus on what modes a EM Drive cavity can/does support. Is it asking too much to take into account resonance changes in a vacuum, when using the same EM Drive cavity that could effect results?
Would be interesting to see what for example meep results would be for the same EM Drive cavity but in a vacuum. Not sure anyone has even tried to see if there would be any major differences? Not sure if any meep code can deal with the same EM Drive cavity in a vacuum, without doing code changes to perform those calculations?
Don
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#1188
by
rfmwguy
on 03 Jan, 2016 16:17
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I read the deleted posts and I can't help but don't see any reason for this "cleaning" campaign at all 
I'm not taking sides although I think being open to see both sides is important.
I know moderators read and even comment on other postings in other threads and I'm sure due to the nature of this thread you can be assured this one is as well.
Another note...
We all are waiting for good solid data to hit, (me probably more than anyone here). I wonder how many visit more than once a day hoping to read about some test, some computational results, so we don't loose touch on this hot topic.
The stakes could be enormous if you consider what Paul March posted in his bombshell "And yet the anomalous thrust signals remain...".
Great minds...I agree shell. I really think people are attracted here for something new. New tests, theories, data and pics (hahaha)
As I said before, you OWE us and we want data...actually, you owe us nothing and we are grateful you are out there tearing apart your home to make room for an experiment just to give us data. For that, I commend you. Can't wait to see it...and yes, I didn't spill the beans 
I have some equipment to order this week. Getting a set of digital logging scales because this last time convinced me that there was no way I could monitor the display by videoing, the blurring the digital scale display made it almost unreadable. Still plan of videoing the new digital scales.
I have a few other mods I'm going to be doing, but working on delivery times and costs. When I have those figures down better I'll let everyone know what it is I'm doing and how I'm doing it.
Nice work shell. Before you do the digital scale thing, did you consider beam deflection monitoring via laser displacement sensor?
I found this simple and easy to integrate and rebound or resistance forces are nil since its a laser spot only. I believe a scale will add some degree of attenuation to movement once your emdrive fires up...may not much, but some.
Either way your data should be great. Lds is just a non-contact method.
Send me the info, I'll look at it again. Still trying to resurrect and file all the data again.
Shell below is the lds I used and my test report that calls out the model. Its an old style Omron and newer models are available. Distance measuring was 40 +/- 10 mm.
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#1189
by
Mulletron
on 03 Jan, 2016 16:36
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Okay so this ref is useful because it provides a step by step example of how to derive the gravitomagnetic field (though at the moment I'm missing inputs such as mass current density) and then how to calculate the force on another moving mass (one of the reasons I wanted to vibrate the atoms within the cavity using sound) using the gravitomagnetic Lorentz force. The above example uses a steady state mass current, in this case, a line of 747 jumbo jets.
http://web.stanford.edu/~oas/SI/SRGR/notes/Gravitomagnetism.pdfThe force is so small.
I am pleased to see that the value for gravitomagnetic permeability are in agreement across the above ref and others I've found. ~9.3x10-27 m/kg
http://mtaonline.net/~hheffner/FullGravimag.pdf (watch out, this one also contains super speculative info)
http://www.journaloftheoretics.com/articles/3-1/tajmar-final.htm (This is from Tajmar. Much of his work is on gravitomagnetism.)
Side note. I'm intrigued by the concept of relative gravitomagnetic permeability. I wonder how might one engineer a material to modify this property? Would you line up all the spin magnetic moments? Line up all the moments of inertia of the atoms in such material? Some other way?
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#1190
by
VAXHeadroom
on 03 Jan, 2016 18:05
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Well...a cavity filled with nitrogen rather than hydrogen might be a better idea
Yes, but I was thinking along the lines to choose the smallest atom to fill the cavity contents. Which is why I suggested Hydrogen. But any gas and pressures used. Would be an interesting additional test using the same EM Drive testbed.
Don
Good points. I've had arcing in some of my earlier static tests...for a second there I was imagining lakehurst, nj 
My spherical end plate frustum will be sealed, with a digital pressure gauge and port. Plan to do tests at 1 Torr atmo, 1 Torr N2, normal atmo & normal atmo N2. Can pump down and fill with most gases. Really not interested in using H2. Have experience with it and the leak rate.
Yeah hydrogen leaks through everything. ARGON is probably the right answer as it is readily available from welding suppliers and inert!
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#1191
by
VAXHeadroom
on 03 Jan, 2016 18:08
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I believe you can see the mode in this animation of 10 slices for on cycle and how it relates to Maxheadroom's graphic in thermal. I paused it at the peak of of the energy in the mode to see. It matches the CSV data quite closely. How close it matches the real world using the thermal camera is to be seen.
Shell
Added: What would be interesting is to drop the small end CSV data sample down into the mode and see it it also agrees and the difference in energy levels.
I'm on it.
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#1192
by
zen-in
on 03 Jan, 2016 18:25
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...
But no test data was produced using their EM Drive comparing the cavity using normal atmospheric contents and at normal atmospheric pressure in their vacuum chamber vs. the cavity being at vacuum pressure. To date, I don't think a test like that in a vacuum has ever been tried, with a EM Drive?
Don
This test would be difficult to do. If you had a fustrum that was 12" high, 10" wide at the big end, and 3.3" wide at the small end and it contained a gas at 1000 Torr, there would be a total of 4600 pounds pressure distributed over the whole surface, in a vacuum. I don't believe a Copper fustrum made from even 1/8" thick sheet could withstand that. Since it is very difficult to fabricate an air-tight fustrum from even light gauge sheet Copper (.020" - .050"), a stand-alone Copper fustrum would not work.
It might be a valid experiment if the Copper fustrum was enclosed inside a pressure vessel. The heat conduction to the pressure vessel's walls would be slow. The pressure vessel with the Copper fustrum, both at atmospheric pressure with the desired gas, could be suspended inside a vacuum chamber. That test might prove the OP theory.
The other option is to have a pressure vessel whose inside contours match the outer contours of a Copper fustrum and fabricated from stainless. Then a Copper fustrum would be inserted inside the stainless pressure chamber. Connecting the RF source, etc are more challenging problems but they can be overcome if someone is determined enough to do this experiment. All it takes is a lot of money. The advantage of doing the experiment this way is that one could safely fill the inner vessel with pure Hydrogen.
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#1193
by
Prunesquallor
on 03 Jan, 2016 19:04
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...
But no test data was produced using their EM Drive comparing the cavity using normal atmospheric contents and at normal atmospheric pressure in their vacuum chamber vs. the cavity being at vacuum pressure. To date, I don't think a test like that in a vacuum has ever been tried, with a EM Drive?
Don
This test would be difficult to do. If you had a fustrum that was 12" high, 10" wide at the big end, and 3.3" wide at the small end and it contained a gas at 1000 Torr, there would be a total of 4600 pounds pressure distributed over the whole surface, in a vacuum. I don't believe a Copper fustrum made from even 1/8" thick sheet could withstand that. Since it is very difficult to fabricate an air-tight fustrum from even light gauge sheet Copper (.020" - .050"), a stand-alone Copper fustrum would not work.
...
It would also entail some pretty significant hazards. A failure such as a split seam or a blown out end cap could really wreak havoc.
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#1194
by
rfmwguy
on 03 Jan, 2016 20:06
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#1195
by
aero
on 03 Jan, 2016 21:02
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You are aware, are you not, that most EW tests were in atmosphere. All tests reported in the "Anomalous Thrust..." paper were in a vacuum chamber with the door closed but not pumped down, (that is, at atmospheric pressure). The reason given was time schedule pressure and the 2-3 days needed to draw down a good vacuum.Only later (2015) did they actually pump the vacuum chamber down to test in moderate vacuum.
Yes.
But, as you know there has been a major focus on what modes a EM Drive cavity can/does support. Is it asking too much to take into account resonance changes in a vacuum, when using the same EM Drive cavity that could effect results?
Would be interesting to see what for example meep results would be for the same EM Drive cavity but in a vacuum. Not sure anyone has even tried to see if there would be any major differences? Not sure if any meep code can deal with the same EM Drive cavity in a vacuum, without doing code changes to perform those calculations?
Don
I've ran a lot of those cases, there's no discernible difference with meep.
Probably that is in part because internally, meep treats the material properties of air and of vacuum as the same. There is the difference in the speed of light, which is a user specified parameter but nothing internal to meep, AFAIK.
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#1196
by
TheTraveller
on 03 Jan, 2016 21:26
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I think it's safe to say that changes in cavity contents, temperature and pressures would and does cause changes in resonance for the same EM Drive.
Don
Atmo to vac causes approx 600 kHz increase in resonant freq. This is easily shown via the spreadsheet and had been measured.
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#1197
by
TheTraveller
on 03 Jan, 2016 21:36
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You are aware, are you not, that most EW tests were in atmosphere. All tests reported in the "Anomalous Thrust..." paper were in a vacuum chamber with the door closed but not pumped down, (that is, at atmospheric pressure). The reason given was time schedule pressure and the 2-3 days needed to draw down a good vacuum.Only later (2015) did they actually pump the vacuum chamber down to test in moderate vacuum.
Aero,
The other issue is that, in atmo, the frustum is manually tuned to obtain the best Force generation.
During vac runs, the tuning alters and needs to be adjusted, prior to the pump down, from the atmo settings to best guess vac settings. I suspect that if Paul could put on a vac suit and do his manual tuning inside the vac chamber, that the vac Force results would be much higher.
It also doesn't help that the Rf amp dumps it's waste heat onto the big end plate.
Would really like EW to do what Shell has done and thermally separate the frustum from all other heat sources.
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#1198
by
oyzw
on 04 Jan, 2016 00:45
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Excuse me who studied superconducting Rf niobium cavity?In superconducting Rf niobium cavity, there is a huge surface lorentz force.
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#1199
by
OnlyMe
on 04 Jan, 2016 01:37
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Other than as it affects experimental results, why would Lorentz forces be a problem for a satellite or other space application?
