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#120 by X_RaY on 19 Nov, 2016 11:05
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"According to Woodward, who saw a copy of the paper shortly after it had been accepted for peer review, the main difference between the accepted copy and the leaked early release is that the latter has way more theory trying to explain the results. Supposedly the AIAA would only accept the paper if White and his colleagues ditched the quantum vacuum theory and just published the results of their research without trying to explain it."
http://motherboard.vice.com/read/the-fact-and-fiction-of-the-nasa-emdrive-paper-leak
So this is not true. Their pilot wave theory is still in the Discussion.
This theory is very interesting especially since it's compatible with known physics / is nothing else like a different physical interpretation of the equations.
Here is one of my favorite videos about it:
Very impressive is the coordinate probability of detection of the droplet equals a similar quantum system as shown in the video.
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#121 by X_RaY on 19 Nov, 2016 12:08
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Good question.Quote from: X_RaYVery impressive is the coordinate probability of detection of the droplet equals a similar quantum system as compared, see video at 1:40.
Would that also find application in quantum cypher decoding?
There may exist hidden variables which are summarized in the known viewpoint (Copenhagen interpretation). For example there could be a similar process like in the video at much shorter time scales we can not measure yet so that we see the result as a wave function only with a defined propabillity of detection, not a particle with sharp defined coordinate and velocity at the same time(Uncertainty principle).
On the other hand effects like quantum entanglement seems impossible over large distances in this pic also.
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#122 by Rodal on 19 Nov, 2016 17:37
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Results for Brady cone with HDPE-disc at the small end plate. Source power was defined to be 1Watt (30dBm).
X_Ray, we have to be careful with calling this mode shape "TM010". While that name is correct for an empty cylinder (with no dielectric insert partially filling the cavity), which can have a constant field in the longitudinal direction. We know that the fields cannot be constant in the longitudinal direction for a cone (even for an empty cone), from the exact analytical solution, because a constant electromagnetic field in the longitudinal direction cannot satisfy the boundary conditions for a cone, (as verified by your FEKO boundary element analysis results). Since the electromagnetic fields are not constant in the longitudinal direction, p is not equal to zero. So this is a degenerate form of TM010, perhaps we should call it TM01?. This mode shape becomes TM010 as one varies the cone angle to zero, such that the cone becomes a cylinder. As the cone becomes a cylinder, the electromagnetic fields become constant in the longitudinal direction.
εR=2.27
tanδ=0.00031
DIA*=158.75mm
Height=54mm
* to simplify the model I used a diameter equal to the end plate diameter instead of the 156.7mm reported by EW
In particular, it is interesting how the electromagnetic fields, in particular the E field has a gentle gradient at each end, in order to accommodate the boundary conditions at each end, and the fact that the field cannot be constant in the longitudinal direction.
NO dielectric
~~~~~~~~~~~~~~
SMALL END dielectric
~~~~~~~~~~~~~~
BIG END dielectric -
#123 by X_RaY on 19 Nov, 2016 18:15
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Yes I have to agree. Especially in the case where the dielectric is at the big end it causes to make the frustum virtually even more asymmetric due to the contracted wavelength inside the dielectric disc. Thefore the field at the small end tends to zero and the standardnotation for cylindrical cavities doesn't make sense any more.Results for Brady cone with HDPE-disc at the small end plate. Source power was defined to be 1Watt (30dBm).
X_Ray, we have to be careful with calling this mode shape "TM010". While that name is correct for a cylinder, which can have a constant field in the longitudinal direction. We know that the fields cannot be constant in the longitudinal direction for a cone, from the exact analytical solution, because a constant electromagnetic field in the longitudinal direction cannot satisfy the boundary conditions for a cone, (as verified by your FEKO boundary element analysis results). Since the electromagnetic fields are not constant in the longitudinal direction, p is not equal to zero. So this is a degenerate form of TM010, perhaps we should call it TM01?. This mode shape becomes TM010 as one varies the cone angle to zero, such that the cone becomes a cylinder. As the cone becomes a cylinder, the electromagnetic fields become constant in the longitudinal direction.
εR=2.27
tanδ=0.00031
DIA*=158.75mm
Height=54mm
* to simplify the model I used a diameter equal to the end plate diameter instead of the 156.7mm reported by EW8
In particular, it is interesting how the electromagnetic fields, in particular the E field has a gentle gradient at each end, in order to accommodate the boundary conditions at each end, and the fact that the field cannot be constant in the longitudinal direction.
...snip...
If my memory serves this problem remains over several threads now, but till now I have no idea for a notation that make more sense. In this regard conclusive ideas are very welcome to solve this issuse!
EDIT
Maybe a notation based on spherical coordinates fits better?
Rectangular cavity --> TX x,y,z
Cylindrical cavity--> TX φ,R,z
sections of a sphere just like Conical cavities --> TX φ,θ,r or semi-spherical TX φ,R,r
While TE/TM depends on the dominant component into "r" direction?
Does this make sense?
Which notation would make sense in a wedge shaped cavity?
Regarding boundary conditions, what if the modal shape inside the small end don't equals at all the shape near the larger end?
hence
x, y = quantum number; m∧n*λ/2, along this axis in cartesian coordinates
z= quantum number, p* λ/2, along this axis in cylindrical or cartesian coordinates
φ= quantum number/number of full wavelength for 360°/λ, around the central axis of symmetry in both cylindrical and sperical coordinates
r= quantum number, radius measured from the apex in sperical coordinates (full quantum number, p*λ/2, similar to "z" in cartesian or cylindrical coordinates)
R= quantum number, radius of a cross section in cylindrical coordinates(full quantum number, R*λ/2)
θ= quantum number, measured against the "r" axis up to the conductive wall like "R" in cylindrical coordinates, but along a shell section at a constant radius "r" in special coordinates
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#124 by Rodal on 19 Nov, 2016 20:42
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...snip...
Yes I have to agree. Especially in the case where the dielectric is at the big end it causes to make the frustum virtually even more asymmetric due to the contracted wavelength inside the dielectric disc. Thefore the field at the small end tends to zero and the standardnotation for cylindrical cavities doesn't make sense any more.
If my memory serves this problem remains over several threads now, but till now I have no idea for a notation that make more sense. In this regard conclusive ideas are very welcome to solve this issuse!
EDIT
Maybe a notation based on spherical coordinates fits better?
Rectangular cavity --> TX x,y,z
Cylindrical cavity--> TX φ,R,z
sections of a sphere just like Conical cavities --> TX φ,θ,r or semi-spherical TX φ,R,r
While TE/TM depends on the dominant component into "r" direction?
Does this make sense?
Which notation would make sense in a wedge shaped cavity?
Regarding boundary conditions, what if the modal shape inside the small end don't equals at all the shape near the larger end?
Regarding nomenclature for mode shapes, I just checked and my old article had this note http://forum.nasaspaceflight.com/index.php?topic=39214.msg1526577#msg1526577 reading:
(**) Mode shape nomenclature is adopted as per the cylindrical cavity (with constant circular cross section) designation, because there is no standardized way to number truncated cone mode shapes. I am aware that there is no mode shape for a truncated cone with electromagnetic fields constant in the longitudinal direction, unlike cylindrical cavities which have TM mode shapes with "p=0". Still, because the truncated cone geometries used up to now have shapes that are not too far from a cylinder with constant cross section (because small cone angles are used and the cones are truncated far from the cone vertex) it is possible to use a cylindrical cavity mode shape designation and select m,n,p accordingly.
The problem with us adopting a more logical nomenclature is that at this point in time only you and I probably will understand it, and it would make it difficult to communicate with others. It would be like you and I communicating in Esperanto (https://en.wikipedia.org/wiki/Esperanto ), rather than English. We use English with all its flaws (one of the least structured languages) simply because it is spoken and understood by most people
This mode shape (TM010?) is particularly problematic regarding nomenclature for a truncated cone, unlike a mode shape like TM212 that would not present as much of a problem with interpretation. I wonder why JPM asked for this particular mode shape... -
#125 by X_RaY on 20 Nov, 2016 15:36
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Jean-Philippe,Quote from: JPMontillet, PM
If you increase the diameter for the large end to cover it completely...
this is the result for the alternative situation with the increased size of the HDPE dielectric. Source power was defined to be 1Watt (30dBm) as before. Height of the dielectric is still 54mm, diameters are modified to fit into the frustum.
The last pic shows that the frequency is even lower due to the increased volume of the dielectric as expected.
Note: dont use the numbers for power of it, but the resonant frequency, because this sim was performed to find the frequency only and the input power was not defined to 1W as for the other plots.
Regards
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#126 by WarpTech on 26 Nov, 2016 05:46
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Satisfying Gauss's law and conservation of momentum.
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#127 by X_RaY on 27 Nov, 2016 19:43
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Monomorphic, regarding your PM
This is just an example for a almost fitting loop antenna inside the brady cone without dielectric for TE012 using a 50Ω voltage source in FEKO FEA. Of course i have to run it again because it's still not converged. It shows the way to get impedance match to the frustum.
Wire radius is 1mm. The loop dimension is shown in the pic.
This was just my second try the first version leaded to the same overcoupling as in your model.
Best regards
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#128 by Monomorphic on 27 Nov, 2016 21:49
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Thanks to X_Ray I'm getting closer to impedance match with a loop antenna. I'm still over coupled. This goes much more slowly as I have to run 30+ minute sweeps with each iteration. I'm also using spherical end-plate geometry. Running another sweep now.
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#129 by X_RaY on 28 Nov, 2016 05:13
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Looks better now
Not exact 50 Ohm but very close.
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#130 by Monomorphic on 28 Nov, 2016 14:00
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Looks better now
Not exact 50 Ohm but very close.
Can you post the antenna location and dims?
Here is my second try. Why is is pointed? How did you get yours to be a nice circle?
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#131 by X_RaY on 28 Nov, 2016 16:16
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It's almost the same as shown above. Distance to the base plate is 19mm. Since you use spherical plates you may change it to the correlated coordinates in your model.Looks better now
Not exact 50 Ohm but very close.
Can you post the antenna location and dims?
Here is my second try. Why is is pointed? How did you get yours to be a nice circle?
Do not use a very coarse self defined mesh if possible.
My PC runs all night to solve a model need a new one.
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#132 by Rodal on 28 Nov, 2016 22:06
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...Do not use a very coarse self defined mesh if possible.
Monomorphic, we had discussed previously my viewpoint that the mesh in your FEKO analyses are too coarse.
My PC runs all night to solve a model need a new one.
This would be an interesting case study where you could perform a convergence analysis to analyze the effect of mesh size on these parameters. Then you could post it here for posterity so that we can all learn about the dependence of the solution on the mesh size.
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#133 by Monomorphic on 29 Nov, 2016 00:17
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...Do not use a very coarse self defined mesh if possible.
Monomorphic, we had discussed previously my viewpoint that the mesh in your FEKO analyses are too coarse.
My PC runs all night to solve a model need a new one.
This would be an interesting case study where you could perform a convergence analysis to analyze the effect of mesh size on these parameters. Then you could post it here for posterity so that we can all learn about the dependence of the solution on the mesh size.
FEKO has the ability to use coarse, standard, and fine meshes. I'm currently using the fine mesh. In addition, FEKO includes the option to solve MoM using higher-order basis functions (HOBF).
"the extension of the method of moments (MoM) and multilevel fast multipole method (MLFMM) in FEKO to include higher-order basis functions (HOBFs) on curvilinear triangular patches. HOBFs reduce the number of unknowns, memory and run-time compared to the traditional planar Rao-Wilton-Glisson (RWG) basis functions."
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#134 by Monomorphic on 29 Nov, 2016 12:52
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Another run with antenna more towards bottom. Finally starting to get some reflection coefficient numbers that are useful. I hit -12dB on one run but didn't save it. With -5dB, this resonator/antenna system has a Q of 76,406 using the -3dB method. E-field strength is also inching up. I'm still significantly over coupled so lets see what happens when that improves.
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#135 by X_RaY on 30 Nov, 2016 19:57
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Currently I'm solving monomorphics model with spherical end plates with a modified loop antenna, i.e. position and diameter. The current result is shown below. It shows that using the related dimensions leads to a coupling factor below 1.
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#136 by Rodal on 30 Nov, 2016 20:03
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Currently I'm solving monomorphics model with spherical end plates with a modified loop antenna, i.e. position and diameter. The current result is shown below. It shows that using the related dimensions leads to a coupling factor below 1.
Are you also using FEKO?
How come you get a perfect circle
instead of the unphysical coarse-sided polygon in Monomorphic's FEKO results? -
#137 by X_RaY on 30 Nov, 2016 20:15
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Yes. I have a copy of his model and was able to run it with the FEKO version I have available. The mesh is a little coarser while searching for the right antenna coordinates and shape but the number of sample frequencys is much higher. When the result looks like impedance match is reached, I will increase the mesh to the finest possible level whats solvable with the students version of the software. I will share the results when Its done.Currently I'm solving monomorphics model with spherical end plates with a modified loop antenna, i.e. position and diameter. The current result is shown below. It shows that using the related dimensions leads to a coupling factor below 1.
Are you also using FEKO?
How come you get a perfect circle
instead of the unphysical coarse-sided polygon in Monomorphic's FEKO results?
EDIT
While looking to the raw data I am not sure what the reason is that the curve seems so smooth
Most of the points are not at the circle. It seems the smoothing algorithm works better due to some reason or its not applied if there are too less samples.
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#138 by Monomorphic on 01 Dec, 2016 16:01
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Currently I'm solving monomorphics model with spherical end plates with a modified loop antenna, i.e. position and diameter. The current result is shown below. It shows that using the related dimensions leads to a coupling factor below 1.
Can you please double check the dimensions for the antenna? A radius of 15mm seems large and i'm still showing over coupled. Did you mean a diameter of 15mm? That seems more in line with EW's 13.5mm diameter loop antenna.
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#139 by as58 on 01 Dec, 2016 20:49
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Satisfying Gauss's law and conservation of momentum.
I'm sorry, but I don't understand even the first line. Where does the first equality come from? The second equality is Lorenz (not Lorentz) gauge, but what does the third equality mean? What do you mean by magnetic flux? Through what surface?
