PS: I understand he says he used the NASA Eagleworks dimensions, if that is the case, the resonant frequency at near 2.45 GHz should be TM212 (transverse magnetic, same mode excited by Iulian Berca), instead of TE212 (transverse electric)
As calculated.
As calculated by NASA: 2.45 GHz TM212 (transverse MAGNETIC mode) (
not TE212) for NASA's truncated cone dimensions (no dielectric insert)
My exact solution agrees with NASA
Full NASA report attached below
PS: I understand he says he used the NASA Eagleworks dimensions, if that is the case, the resonant frequency at near 2.45 GHz should be TM212 (transverse magnetic, same mode excited by Iulian Berca), instead of TE212 (transverse electric)
As calculated.
As calculated by NASA: 2.45 GHz TM212 (transverse MAGNETIC mode) (not TE212) for NASA's truncated cone dimensions (no dielectric insert)
My exact solution agrees with NASA
As calculated by NASA: 1.88 GHz TE212 (transverse ELECTRIC mode occurs at a much lower frequency than 2.45 GHz) for NASA's truncated cone dimensions (no dielectric insert)
My exact solution agrees with NASA
I'm still confused. Are we looking at a single impulsive event, or a steady-state force?
As calculated by NASA: 2.45 GHz TM212 (transverse MAGNETIC mode) (not TE212) for NASA's truncated cone dimensions (no dielectric insert)
My exact solution agrees with NASA
Full NASA report attached below
And the Force they measured when they excited the frustum in TM213 mode at the predicted freq was?
I'm still confused. Are we looking at a single impulsive event, or a steady-state force?
The unraveling of the EM Drive "force measurement" this is what is great about replications.
The South African experiment does not show a constant steady-state force.
His fulcrum is undamped and will oscillate for some time before settling at the final value. You know that so why the comment?
Calculation of resonant frequencies in cavities is well-known and established. Has been replicated routinely in thousands of carefully designed experiments. Routinely done at CERN and other particle accelerators using Finite Element Analysis . The hundreds of thousands of readers of this thread can conduct their own calculations based on the NASA dimensions (see attached NASA report for dimensions frequencies and mode shape) and independently verify whether the mode shape at 2.45 GHz is TM212 or TE212
I'm still confused. Are we looking at a single impulsive event, or a steady-state force?
The unraveling of the EM Drive "force measurement" this is what is great about replications.
The South African experiment does not show a constant steady-state force.
His fulcrum is undamped and will oscillate for some time before settling at the final value. You know that so why the comment?
There is always some amount of damping in any set-up (if there would be no damping we would be able to have perpetual motion machines, which is impossible). But fair enough, since I have not had a chance to do detailed modeling of his set-up (I don't even know his dimensions) I withdraw my comments until I have the chance to model his set-up.
Can you provide a link to his cone dimensions, masses, displacement/force measuring device, etc., for me to model his experiment?
PS: I understand he says he used the NASA Eagleworks dimensions, if that is the case, the resonant frequency at near 2.45 GHz should be TM212 (transverse magnetic, same mode excited by Iulian Berca), instead of TE212 (transverse electric)
As calculated.
As calculated by NASA: 2.45 GHz TM212 (transverse MAGNETIC mode) (not TE212) for NASA's truncated cone dimensions (no dielectric insert)
My exact solution agrees with NASA
As calculated by NASA: 1.88 GHz TE212 (transverse ELECTRIC mode occurs at a much lower frequency than 2.45 GHz) for NASA's truncated cone dimensions (no dielectric insert)
My exact solution agrees with NASA
Proof of frustum resonance in any mode is measured Force generation. No Force generation, means the mode and resonance calc is not correct.
What NASA needs to show is the S11 return loss scans for those frequencies. When you see the return loss dB dips, then you know there is a resonant mode. Need a different antenna to properly excite TE and TM modes.
EW's internal frustum length only needs to be 3mm longer than SA Paul's frustum length for the 2.445GHz resonance to turn into a 2.422GHz resonance.
Thus I suggest the attached does show a TE213 resonance that EW found, Paul in SA found and my spreadsheet predicts.
...
Proof of frustum resonance in any mode is measured Force generation. No Force generation, means the mode and resonance calc is not correct.
What NASA needs to show is the S11 return loss scans for those frequencies. When you see the return loss dB dips, then you know there is a resonant mode. Need a different antenna to properly excite TE and TM modes.
EW's internal frustum length only needs to be 3mm longer than SA Paul's frustum length for the 2.445GHz resonance to turn into a 2.422GHz resonance.
Thus I suggest the attached does show a TE212 resonance that EW found, Paul in SA found and my spreadsheet predicts.
Therefore according to you CERN, MIT, CalTech, Princeton, etc., and anybody that calculates frequencies and mode shapes of resonant cavities using Finite Element analysis and exact solutions are getting wrong results and they should immediately switch to using your Excel spreadsheet to calculate resonant frequencies and mode shapes of resonant cavities?
X-Ray and others in this thread, for example should replace their methods of analysis and start using your Excel spreadsheet to calculate resonant frequencies and mode shapes?
Calculation of resonant frequencies in cavities is well-known and established. Has been replicated routinely in thousands of carefully designed experiments. Routinely done at CERN and other particle accelerators using Finite Element Analysis . The hundreds of thousands of readers of this thread can conduct their own calculations based on the NASA dimensions (see attached NASA report for dimensions frequencies and mode shape) and independently verify whether the mode shape at 2.45 GHz is TM212 or TE212
As I said proof of the calc is seeing a S11 return loss dip at the calculated freq. Is easy to do. EW has the VNA to do the scan. So why no scans to back the calcs?
...
Proof of frustum resonance in any mode is measured Force generation. No Force generation, means the mode and resonance calc is not correct.
What NASA needs to show is the S11 return loss scans for those frequencies. When you see the return loss dB dips, then you know there is a resonant mode. Need a different antenna to properly excite TE and TM modes.
EW's internal frustum length only needs to be 3mm longer than SA Paul's frustum length for the 2.445GHz resonance to turn into a 2.422GHz resonance.
Thus I suggest the attached does show a TE212 resonance that EW found, Paul in SA found and my spreadsheet predicts.
Therefore according to you CERN, MIT, CalTech, Princeton, etc., and anybody that calculates frequencies and mode shapes of resonant cavities using Finite Element analysis and exact solutions are getting wrong results and they should immediately switch to using your Excel spreadsheet to calculate resonant frequencies and mode shapes?
Point was if NASA had done a S11 return loss scan on the real frustum, to find the freq the return loss dB drops, they would have confirmed their calcs were correct.
As for the other guys they probably use SuperFish to model and design their cavities.
http://www.lanl.gov/projects/feynman-center/technologies/software/poisson-superfish.phpDo a Google search for superfish resonant cavity to turn up a lot of hits.
https://www.google.com.au/search?q=superfish+resonant+cavity&oq=superfish+resonant+cavity&aqs=chrome..69i57.7017j0j4&sourceid=chrome&es_sm=122&ie=UTF-8
There is always some amount of damping in any set-up (if there would be no damping we would be able to have perpetual motion machines, which is impossible). But fair enough, since I have not had a chance to do detailed modeling of his set-up (I don't even know his dimensions) I withdraw my comments until I have the chance to model his set-up.
Can you provide a link to his cone dimensions, masses, displacement/force measuring device, etc., for me to model his experiment?
https://www.reddit.com/r/EmDrive/comments/3gkwcz/build_complete_initial_testing_done_emdrive_build/
I see the dimensions of the truncated cone there but I don't see enough details to do any modeling: no masses and most bothersome, no dimensions or description of the testing set-up except:
A knife-edge fulcrum is composed of a long balancing beam which rests on two razor edges. This allows for very sensitive measurement of minuscule forces such as those produced by an EMDrive.
One issue that could become a problem is air currents which could potentially give false positives. Once the frustum is set up on the fulcrum with a counterweight the fulcrum will be left for 10 minutes in the testing room. The setup will then be powered on for a burst of 10 seconds.
The frustum will be suspended in an upright position below the beam of the fulcrum. A laser will be attached to the other end of the beam which will project onto graph paper. This setup will detect any upwards or downwards forces on the frustum. A camera is positioned perpendicular to the graph paper to make measurements of the laser point.
One for example could say that the erratic oscillations are just due to convection currents in the air and unrelated to the EM Drive (as shown by the videos of rfmwguy). Not way to know from this brief description.
Calculation of resonant frequencies in cavities is well-known and established. Has been replicated routinely in thousands of carefully designed experiments. Routinely done at CERN and other particle accelerators using Finite Element Analysis . The hundreds of thousands of readers of this thread can conduct their own calculations based on the NASA dimensions (see attached NASA report for dimensions frequencies and mode shape) and independently verify whether the mode shape at 2.45 GHz is TM212 or TE212
As I said proof of the calc is seeing a S11 return loss dip at the calculated freq. Is easy to do. EW has the VNA to do the scan. So why no scans to back the calcs?
My limited experience with the comsol EM module is it works fine!
Without calculations it is difficult(not possible) to say a specific peak in the S-parameter plot is the target resonance. I am sure EW did both, calculations and measurements
My limited experience with the comsol EM module is it works fine!
Without calculations it is difficult(not possible) to say a specific peak in the S-parameter plot is the target resonance.
Sure understand that. But if you do a scan on a cavity and the predicted resonance is not there, then what?
As far as I know, there were no scans to back up all the mode and freq calculations that EW did.
I see the dimensions of the truncated cone there but I don't see enough details to do any modeling: no masses and most bothersome, no dimensions or description of the testing set-up except:
This info is in his report. How is this not enough info to do an analysis?
Hypothesis Test 1 – NASA cavity size at 2450MHz
When microwaves are supplied into the cavity, a thrust will be produced by the frustum.
Hypothesis Test 2 – Frustum extended by 50 mm excited at 2450MHz
When microwaves are supplied into the cavity, a greater thrust will be produced by the increase in resonance.
The specifications of the frustum are as follows
Height (perpendicular): 228 mm (1) 278mm (2)
Big Diameter: 279.4mm
Small Diameter: 158.8mm
Material: Copper
Antenna location: 34.29 mm from Big Diameter
I see the dimensions of the truncated cone there but I don't see enough details to do any modeling: no masses and most bothersome, no dimensions or description of the testing set-up except:
This info is in his report. How is this not enough info to do an analysis?
Hypothesis Test 1 – NASA cavity size at 2450MHz
When microwaves are supplied into the cavity, a thrust will be produced by the frustum.
Hypothesis Test 2 – Frustum extended by 50 mm excited at 2450MHz
When microwaves are supplied into the cavity, a greater thrust will be produced by the increase in resonance.
The specifications of the frustum are as follows
Height (perpendicular): 228 mm (1) 278mm (2)
Big Diameter: 279.4mm
Small Diameter: 158.8mm
Material: Copper
Antenna location: 34.29 mm from Big Diameter
Do you understand how to model the dynamic oscillations of the knife-edge fulcrum composed of a long balancing beam which rests on two razor edges ?
You repeated the dimensions of the truncated cone, again, as I wrote:
I see the dimensions of the truncated cone there but I don't see enough details to do any modeling: no masses and most bothersome, no dimensions or description of the testing set-up except
no dimensions of the knife-edge fulcrum composed of a long balancing beam which rests on two razor edges
no masses
Is there even a photograph from which one can guesstimate dimensions of the "long balancing beam", etc.?
Do you understand how to model the dynamic oscillations in a testing set-up ?
1st you need to confirm resonance. Last time that I remember you commented there was no resonance for the EW copper frustum at 2.45GHz. Might try that again and over the range +-30MHz.
Do you understand how to model the dynamic oscillations in a testing set-up ?
1st you need to confirm resonance. Last time that I remember you commented there was no resonance for the EW copper frustum at 2.45GHz. Might try that again and over the range +-30MHz.
Sigh. Hand over the discussion with TheTraveller of the South African experiment to you deltaMass and Frobnicat
PS: I never said that there was no resonance for the EW copper frustum at 2.45GHz
that is a complete canard. I even gave the TM212 resonance frequencies to Mulletron for his NASA-dimensioned experiment at 2.45 GHz and put the Iulian Berca mode shape TM212 at 2.45GHz in the EM Drive wiki accordingly.
Unbelievable for TheTraveller to say such a canard. I even submitted to his attention (and SeeShell quoted in one of her messages) a complete table, for all NASA calculated frequencies from below 1GHz to 2.5GHz comparing my exact solution results to NASA results including TM212 at 2.45Ghz
