I understand why the EW unit generates such a low reaction Force in vac. Will not effect my design. In fact if it was not for my advise and input to incresse it, the EW vac force would be so small, EW might be now closed down.
There is so much going on that can't be shared on NSF. ...
Concerning your statement
<< In fact if it was not for my advise and input to incresse it, the EW vac force would be so small, EW might be now closed down.>>
does the acronym EW stand for NASA's Eagleworks laboratory efforts under Dr. White ?
(am I reading this correctly that you are stating that in fact if it was not for your advise and input, NASA's Eagleworks laboratory would have been shut down ?)
or does the acronym EW stand for something else?
I agree the position can be optimized. To stay clear there will ever a difference remain between eigen resonance conditions of an empty cavity and the reality because you need an antenna to excite the field. Add something into such a resonator it leads to interferences as well even its the antenna itself.
I mean that's the price one have to pay, its almost not possible to get PERFECT pattern the only one can get is a nearly perfect mode shape.
It seems your lower pic with the perfect pattern depends on a plane waveguid port at the small end? i.e. the whole plate radiates and maybe with the right polarisation*.
*dont know if feko use "m" "n" in circular coordinates at a round plate, but I don't think so.
It seems your lower pic with the perfect pattern depends on a plane waveguid port at the small end?
The bottom image has the mode specified, so I t's not dependent on frequency. I posted another example of perfect TE013 I found at 2.45Ghz using the newer wedge-shape geometry Shawyer is using. Will post that again after breakfast. I know I have numerous other examples in the sweeps I've done.
I understand why the EW unit generates such a low reaction Force in vac. Will not effect my design. In fact if it was not for my advise and input to incresse it, the EW vac force would be so small, EW might be now closed down.
There is so much going on that can't be shared on NSF. ...
Concerning your statement
<< In fact if it was not for my advise and input to incresse it, the EW vac force would be so small, EW might be now closed down.>>
does the acronym EW stand for NASA's Eagleworks laboratory efforts under Dr. White ?
(am I reading this correctly that you are stating that in fact if it was not for your advise and input, NASA's Eagleworks laboratory would have been shut down ?)
or does the acronym EW stand for something else?
I said "Might". You altered that to "Would". Not nice to change my words..
As you were cced into the relevant email corro with Eagleworks staff, shall I post the emails here so all can decide?
I understand why the EW unit generates such a low reaction Force in vac. Will not effect my design. In fact if it was not for my advise and input to incresse it, the EW vac force would be so small, EW might be now closed down.
There is so much going on that can't be shared on NSF. ...
Concerning your statement
<< In fact if it was not for my advise and input to incresse it, the EW vac force would be so small, EW might be now closed down.>>
does the acronym EW stand for NASA's Eagleworks laboratory efforts under Dr. White ?
(am I reading this correctly that you are stating that in fact if it was not for your advise and input, NASA's Eagleworks laboratory would have been shut down ?)
or does the acronym EW stand for something else?
I said "Might". You altered that to "Would". Not nice to change my words..
As you were cced into the relevant email corro with Eagleworks staff, shall I post the emails here so all can decide?
specifically what <<advise and input >> are you referring to, that
<< In fact if it was not for ...advise and input to incresse it, the EW vac force would be so small, EW might be now closed down.>> ?
what are you referring to?
I certainly don't recall any such "advice and input" from you that "might" have had such an effect on NASA.
I understand why the EW unit generates such a low reaction Force in vac. Will not effect my design. In fact if it was not for my advise and input to incresse it, the EW vac force would be so small, EW might be now closed down.
There is so much going on that can't be shared on NSF. ...
Concerning your statement
<< In fact if it was not for my advise and input to incresse it, the EW vac force would be so small, EW might be now closed down.>>
does the acronym EW stand for NASA's Eagleworks laboratory efforts under Dr. White ?
(am I reading this correctly that you are stating that in fact if it was not for your advise and input, NASA's Eagleworks laboratory would have been shut down ?)
or does the acronym EW stand for something else?
I said "Might". You altered that to "Would". Not nice to change my words..
As you were cced into the relevant email corro with Eagleworks staff, shall I post the emails here so all can decide?
specifically what <<advise and input >> are you referring to, that
<< In fact if it was not for ...advise and input to incresse it, the EW vac force would be so small, EW might be now closed down.>> ?
what are you referring to?
I certainly don't recall any such "advice and input" from you that "might" have had such an effect on NASA.
1st point.
You changed my "might" to "would". Do you apologise for misquoting me?
2nd point.
Will retrieve the subject emails and post as your memory seems faulty.
...
1st point.
You changed my "might" to "would". Do you apologise for misquoting me?
2nd point.
Will retrieve the subject emails and post as your memory seems faulty.
1) I quoted your statement verbatim including your use of "EW might". It is incorrect to say that I misquoted you. Please read my post again and you will see that the quotation (under "quote" and under <<>>) is verbatim.
My writing "would" instead of "might" was carefully prefaced by "am I reading this correctly", so there was no intention to change any words. I wanted to understand what you wrote, and any clarification is appreciated.
Another update on the Hackaday drive project. https://hackaday.io/project/10166-emdrive-flight-version/log/35093-emdrive-v4-built
They've got such a cute little integrated baby-EMdrive!
Anything that you (or others) can do to describe the differences and improvements of this latest V4 Baby EM Drive would be highly appreciated by those of us who have not been following the latest developments or/and have a hard time getting such understanding from a fast-reading of the hackaday website.
Thanks
I posted another example of perfect TE013 I found at 2.45Ghz using the newer wedge-shape geometry Shawyer is using. Will post that again after breakfast. .
Here is an example of a very strong TE013 pattern at 2.44889Ghz. In fact, from what I can tell, this wedge/trapezoidal geometry seems to prefer the TE modes, especially TE011, TE012, and TE013.
I posted another example of perfect TE013 I found at 2.45Ghz using the newer wedge-shape geometry Shawyer is using. Will post that again after breakfast. .
Here is an example of a very strong TE013 pattern at 2.44889Ghz. In fact, from what I can tell, this wedge/trapezoidal geometry seems to prefer the TE modes, especially TE011, TE012, and TE013.
I posted another example of perfect TE013 I found at 2.45Ghz using the newer wedge-shape geometry Shawyer is using. Will post that again after breakfast. .
Here is an example of a very strong TE013 pattern at 2.44889Ghz. In fact, from what I can tell, this wedge/trapezoidal geometry seems to prefer the TE modes, especially TE011, TE012, and TE013.
Thank you for this
great analysis.
The result makes sense to me mathematically, because the solution functions for the truncated cone (circular cross-section) involves spherical waves, involving spherical coordinate transformations, where the gradient is
and curl
while the wedge-shaped or
truncated pyramid-shaped geometry involves a square (or rectangular) cross-section with functions that can be analyzed in
separable Cartesian coordinates with simple gradient:
and curl
=
Hence the frustum of a rectangular pyramid is less subject to cross-influence between effects and imperfections in the different intrinsic directions. (Effects previously discussed by X-Ray and Monomorphic)
QUESTION: my reading of your figure is that you have a square cross-section for the big end but a rectangular cross-section for the small-end (not sure because of parallax effects). Is this the same geometry used by SPR Ltd in their BBC video or do they use a wedge-shaped pyramid whereby the small end also has square cross-section ?
FRUSTUM OF A SQUARE PYRAMID
WEDGE (FRUSTUM OF A RECTANGULAR PYRAMID TAPERED IN ONLY ONE DIRECTION)
Is this the same geometry used by SPR Ltd in their BBC video or do they use a wedge-shaped whereby the small end also has square cross-section ?
It is the same geometry used by SPR in their BBC video. Square on the big end, rectangle on the small end. You can see it here.
The frustum of a square pyramid has trouble with TE013. The fields seem to bunch up in the corners instead of wrapping around the "circumference."
The frustum of a square pyramid has trouble with TE013. The fields seem to bunch up in the corners.
Great observation, also makes sense because the frustum of a square pyramid is tapered in both directions while the wedge (with square big end, rectangular small end)
is tapered in only one directionI like your naming it "WEDGE" since it makes it clear that it is
tapered in only one direction, while a truncated rectangular pyramid can be tapered in one direction or both directions.
Tapering in one direction reduces cross-effects, as evident from the curl:
=
where some of those derivative terms are zero when tapered in only one direction, as evident from your image (see how the fields are constant in the non-tapered direction):
compared to
The tapered-in-both-directions frustum of a square pyramid acts more like a frustum of a cone: look at the multipoles in the top square cross-section at the top.
In contrast, the wedge displays constant bands (instead of multipoles) in the top rectangular cross-section.
Monomophics's sweep is of a truncated or trapezoidal prism, not a pyramid.
The superconducting feasibility study also used wedge geometry. I'm nearly ready to run some tests on the TE311 frustum I have now, but am ordering more copper to build a TE013 wedge frustum this week. It looks a lot easier to fabricate without the curved walls! Mounting the magnetron will be simpler on a flat surface as well.
I have only 1 issue that needs to be resolved at the moment in taking my 0.4N EmDrive S band thruster to market.
Finding a hard / high vac test chamber that will be able to test my 0.4N S band thruster for 2 weeks continuous operation. Vac chamber also needs to supply 1.8KW DC power to the thruster.
After that the space industry will need to learn to deal with the reality that the EmDrive works and is commercially available.
BTW, my 0.4N EmDrive S band thruster, if attached to the ISS, will increase orbital velocity by 1m/sec every 12 days. So no more ISS reboosts. Cost to the ISS is an increased electrical load of 1.8kW and 1.8KW or a bit less of waste heat to deal with. Can be mounted internal to the station & easily turned off during docking or departure.
Like SpX, who came from no where and is now very disruptive to the chemical Old Space launch industry, so to will Shawyer Effect Propulsion's 0.4N EmDrive thruster be disruptive to the in space propulsion industry.
BTW "Shawyer Effect Propulsion" is used with permission from Roger Shawyer.
2016 is going to be such an interesting year.
May I suggest you to defer the 0.4N thruster, and focus on the 8mN one at this time? This is because 8mN by itself can be very useful if it is real, and you have had a working prototype. Could you test it in the vacuum chamber instead? And test it on a Cavendish balance? After all, it is better to make sure the force is real, than to scale up the design prematurely.
Monomophics's sweep is of a truncated or trapezoidal prism, not a pyramid.
Monomorphic has done a complete,
thorough analysis, showing results for:
1) Frustum of a cone
2) "Wedge" or "truncated prism with rectangular bases"
3) Frustum of a square pyramid
I agree that #2 should not be called a pyramid. I like the word "wedge" from Monomorphic. It is some kind of a prism, although I'm not sure at the moment of the preferred geometrical term for it. If you (or others) have specific instances with pictures and links of examples showing its preferred terminology, it would be appreciated so that we can agree on a proper terminology for the thread
.
Searching "frustum of a prism" or "truncated prism" or "truncated trapezoidal prism" under Google brings examples of pyramids and other shapes with triangular bases for example.
Thanks
I think the wedge is just called a trapezoidal prism. Though I think it is important to point out that Shawyers wedge had a square big end. "Trapezoidal prism with square base"
"In geometry, a trapezoidal prism is a solid shape that has trapezoid cross-sections in one direction and rectangular cross-sections in the other directions. To compute the volume of a symmetric trapezoidal prism, you need to know four measurements: the length of the prism L, the height of the trapezoidal cross-section H, the base width of the trapezoid B, and the top width of the trapezoid A."
Glad to see Monomorphic is up to doing some exploring ---which IMHO is the thing which is most rewarding (irrespective of outcome). A while back I posted several geometric forms with this in mind. Perhaps (if he has time) Monomorphic would run a sweep on a truncated rectangular pyramid (or at least on the distal portion of a rectangular one)
