Quote from: Rodal on 06/24/2015 02:01 PMQuote from: SeeShells on 06/24/2015 01:57 PMAreo's images in a B/W gif and color. For your viewing pleasure.ShellThat's fantastic !!!!!!!!!!!!!!There is something interesting happening at the small end of the coneCould you please do that for the other views as well ?Thanks so muchSure can do them all, it will take some time. BW or Color?See anything interesting? I see two things.One is right after the cavity fills you see all this very interesting activity in the small end. Not sure if that's an artifact or not.The other is the mode shape in the large end seems to ratchet as the mode shapes from the front bounce into it.Shell

Quote from: SeeShells on 06/24/2015 01:57 PMAreo's images in a B/W gif and color. For your viewing pleasure.ShellThat's fantastic !!!!!!!!!!!!!!There is something interesting happening at the small end of the coneCould you please do that for the other views as well ?Thanks so much

Areo's images in a B/W gif and color. For your viewing pleasure.Shell

Quote from: TheTraveller on 06/24/2015 01:33 PMQuote from: Rodal on 06/24/2015 01:29 PMQuote from: TheTraveller on 06/24/2015 01:14 PM[...Indeed, in the UK when the background force changes were eliminated, in an effortto improve force measurement resolution, no EmDrive force was measured. Thiswas clearly a result of attempting to measure the forces on a fully static thruster,where T and R cancel each other....So, with the EM Drive in deep space, or at a Lagrangian point, where there are no external background forces, the EM Drive would be unable to exert a force on the spaceship and it would just sit still?Why do you always go to the extreme point?There is ALWAYS vibration in any ship. Pumps, motors, compressors, etc. If needed simple to rig up a vibrator to kick things off.If you tell the design engineer it needs an external vibrators source at switch on, no problems. Gets designed into the EMDrive support systems.Wait. Did you just say that they have to smack it with a hammer to get it to work?

Quote from: Rodal on 06/24/2015 01:29 PMQuote from: TheTraveller on 06/24/2015 01:14 PM[...Indeed, in the UK when the background force changes were eliminated, in an effortto improve force measurement resolution, no EmDrive force was measured. Thiswas clearly a result of attempting to measure the forces on a fully static thruster,where T and R cancel each other....So, with the EM Drive in deep space, or at a Lagrangian point, where there are no external background forces, the EM Drive would be unable to exert a force on the spaceship and it would just sit still?Why do you always go to the extreme point?There is ALWAYS vibration in any ship. Pumps, motors, compressors, etc. If needed simple to rig up a vibrator to kick things off.If you tell the design engineer it needs an external vibrators source at switch on, no problems. Gets designed into the EMDrive support systems.

Quote from: TheTraveller on 06/24/2015 01:14 PM[...Indeed, in the UK when the background force changes were eliminated, in an effortto improve force measurement resolution, no EmDrive force was measured. Thiswas clearly a result of attempting to measure the forces on a fully static thruster,where T and R cancel each other....So, with the EM Drive in deep space, or at a Lagrangian point, where there are no external background forces, the EM Drive would be unable to exert a force on the spaceship and it would just sit still?

[...Indeed, in the UK when the background force changes were eliminated, in an effortto improve force measurement resolution, no EmDrive force was measured. Thiswas clearly a result of attempting to measure the forces on a fully static thruster,where T and R cancel each other....

Quote from: SeeShells on 06/24/2015 01:57 PMAreo's images in a B/W gif and color. For your viewing pleasure.ShellCare to share your frustum dimensions and Rf frequency so I can run a few tests?From my experience working with the Calculator your small diameter is way too small to support resonance but I would like to run the numbers. Will give you the data.

Quote from: TheTraveller on 06/24/2015 02:02 PMQuote from: SeeShells on 06/24/2015 01:57 PMAreo's images in a B/W gif and color. For your viewing pleasure.ShellCare to share your frustum dimensions and Rf frequency so I can run a few tests?From my experience working with the Calculator your small diameter is way too small to support resonance but I would like to run the numbers. Will give you the data.Big Dia. 0.27246 msmall dia 0.068115 mlength 0.4890240258freq. 2.14497829E+009 HzPardon all the digits. Big dia. was measured, the other two calculated from big dia and 0.25.

@Rodal - I have: BIG DIAMETER = 0.27246 m SMALL DIAMETER = 0.068115 m LENGTH = 0.4890240258390259 mPardon the extra digits from the calculation.Running in 3-D with bandwidth opened up to 0.5 * drive frequency (drive = ~1.95GHz), Meep finds 4 frequencies:1.58530024E+0091.83409637E+0092.08402579E+0092.33698507E+009 Hz Q - in order620.675008923133.41473139131211.3296422825141.0133154386 This is electric excitation with antenna = 0.2 * wavelength, perpendicular to and centered on the central axis of rotation.OK - I just read the rest of your post. I'll look for the location of the antenna in the Brady cone, and put it there. But as I recall, that was for exciting a TM mode?

On Google Chrome the T animation works fine in color (if one clicks the image). I cannot get the B&W T animation to work on Google Chrome. It freezes.The pattern (for the color animation) never settles down to the symmetric standing wave TE11 pattern (it wants to, but the peak that should be at the center, is instead to the left):wonder whether this is due to not reaching steady-state yet (not enough finite difference time steps have been marched) or whether it is the asymmetric effect of the antenna that is never going to dissapear////////////////One can see the fractal artifact due to the discrete Finite Difference mesh: the fractal artifact is all over at the beginning but it disappears after a while and the fractal artifact only persists at the circular boundary (due to the difficulty of the finite difference mesh to satisfy the boundary conditions on a circular boundary using a Cartesian coordinate system: the Boundary Conditions are only satisfied at the finite difference mesh gridpoints)

Quote from: Rodal on 06/24/2015 02:51 PMOn Google Chrome the T animation works fine in color (if one clicks the image). I cannot get the B&W T animation to work on Google Chrome. It freezes.The pattern (for the color animation) never settles down to the symmetric standing wave TE11 pattern (it wants to, but the peak that should be at the center, is instead to the left):wonder whether this is due to not reaching steady-state yet (not enough finite difference time steps have been marched) or whether it is the asymmetric effect of the antenna that is never going to dissapear////////////////One can see the fractal artifact due to the discrete Finite Difference mesh: the fractal artifact is all over at the beginning but it disappears after a while and the fractal artifact only persists at the circular boundary (due to the difficulty of the finite difference mesh to satisfy the boundary conditions on a circular boundary using a Cartesian coordinate system: the Boundary Conditions are only satisfied at the finite difference mesh gridpoints)It looks like the mode tries to stabilize in the center but the wave energy from the antenna migrating from the side antenna mount pushes and deforms it into the side walls. I can only watch this a couple of times before I want to get my hip huggers, tie dye t-shirts and platform shoes out again.

Quote from: SeeShells on 06/24/2015 03:33 PMQuote from: Rodal on 06/24/2015 02:51 PMOn Google Chrome the T animation works fine in color (if one clicks the image). I cannot get the B&W T animation to work on Google Chrome. It freezes.The pattern (for the color animation) never settles down to the symmetric standing wave TE11 pattern (it wants to, but the peak that should be at the center, is instead to the left):wonder whether this is due to not reaching steady-state yet (not enough finite difference time steps have been marched) or whether it is the asymmetric effect of the antenna that is never going to dissapear////////////////One can see the fractal artifact due to the discrete Finite Difference mesh: the fractal artifact is all over at the beginning but it disappears after a while and the fractal artifact only persists at the circular boundary (due to the difficulty of the finite difference mesh to satisfy the boundary conditions on a circular boundary using a Cartesian coordinate system: the Boundary Conditions are only satisfied at the finite difference mesh gridpoints)It looks like the mode tries to stabilize in the center but the wave energy from the antenna migrating from the side antenna mount pushes and deforms it into the side walls. I can only watch this a couple of times before I want to get my hip huggers, tie dye t-shirts and platform shoes out again. Shell, what is your guess at the best antenna placement, centralized along longitudinal axis? 1/4 up from big end? 1/4 up from small? midway? Polarity perpendicular to longitudinal axis?I can locate my antenna anywhere, just thought I'd ask you and others opinion about 1st locale.

Quote from: rfmwguy on 06/24/2015 03:41 PMQuote from: SeeShells on 06/24/2015 03:33 PMQuote from: Rodal on 06/24/2015 02:51 PMOn Google Chrome the T animation works fine in color (if one clicks the image). I cannot get the B&W T animation to work on Google Chrome. It freezes.The pattern (for the color animation) never settles down to the symmetric standing wave TE11 pattern (it wants to, but the peak that should be at the center, is instead to the left):wonder whether this is due to not reaching steady-state yet (not enough finite difference time steps have been marched) or whether it is the asymmetric effect of the antenna that is never going to dissapear////////////////One can see the fractal artifact due to the discrete Finite Difference mesh: the fractal artifact is all over at the beginning but it disappears after a while and the fractal artifact only persists at the circular boundary (due to the difficulty of the finite difference mesh to satisfy the boundary conditions on a circular boundary using a Cartesian coordinate system: the Boundary Conditions are only satisfied at the finite difference mesh gridpoints)It looks like the mode tries to stabilize in the center but the wave energy from the antenna migrating from the side antenna mount pushes and deforms it into the side walls. I can only watch this a couple of times before I want to get my hip huggers, tie dye t-shirts and platform shoes out again. Shell, what is your guess at the best antenna placement, centralized along longitudinal axis? 1/4 up from big end? 1/4 up from small? midway? Polarity perpendicular to longitudinal axis?I can locate my antenna anywhere, just thought I'd ask you and others opinion about 1st locale.It seems like placing the antenna along the longitudinal axis of symmetry would ensure transverse symmetry. I don't see why doing this would harm any thrust force (if there is any), and being off axis would be detrimental.As to the optimal location on the longitudinal axis (how close to the big base) that depends on the mode shape excited, which depends on the frequency and the geometrical shape of the frustum. One would have to run separate MEEP runs with the antenna in different locations for your geometry, to see where it maximizes the amplitude of the mode shape.The mode shapes do NOT have equi-wavelength along the axis (take a gander at my report, the wave pattern is NOT sinusoidal), the half-wavelength increases towards the small base, hence optimal placement of the antenna is not trivial.

Quote from: SeeShells on 06/24/2015 03:33 PMQuote from: Rodal on 06/24/2015 02:51 PM Shell, what is your guess at the best antenna placement, centralized along longitudinal axis? 1/4 up from big end? 1/4 up from small? midway? Polarity perpendicular to longitudinal axis?I can locate my antenna anywhere, just thought I'd ask you and others opinion about 1st locale.

Quote from: Rodal on 06/24/2015 02:51 PM

Quote from: rfmwguy on 06/24/2015 03:41 PMQuote from: SeeShells on 06/24/2015 03:33 PMQuote from: Rodal on 06/24/2015 02:51 PM Shell, what is your guess at the best antenna placement, centralized along longitudinal axis? 1/4 up from big end? 1/4 up from small? midway? Polarity perpendicular to longitudinal axis?I can locate my antenna anywhere, just thought I'd ask you and others opinion about 1st locale.Center axis, 1/4 wave from small end and perpendicular. I wish you could model a loop but I know meep doesn't have that option. grrr This is the first placement in my testing I'm going to try with extended Rodal's dimensions and shallow angle.Shell

Quote from: SeeShells on 06/24/2015 04:06 PMQuote from: rfmwguy on 06/24/2015 03:41 PMQuote from: SeeShells on 06/24/2015 03:33 PMQuote from: Rodal on 06/24/2015 02:51 PM Shell, what is your guess at the best antenna placement, centralized along longitudinal axis? 1/4 up from big end? 1/4 up from small? midway? Polarity perpendicular to longitudinal axis?I can locate my antenna anywhere, just thought I'd ask you and others opinion about 1st locale.Center axis, 1/4 wave from small end and perpendicular. I wish you could model a loop but I know meep doesn't have that option. grrr This is the first placement in my testing I'm going to try with extended Rodal's dimensions and shallow angle.Shell Shell, I don't know what Rodal's dimensions are , as Rodal is a dimensionless variable.Suggest you provide us with temptative dimensions so that we can analyze your frustum:Inscribed Big Hexagon Diameter=Circumscribed Big Hexagon Diameter=Inscribed Smallest Hexagon Diameter=Circumscribed Smallest Hexagon Diameter=Longitudinal distance between flat hexagonal faces =(measured perpendicular to the flat faces)

Quote from: Rodal on 06/24/2015 03:47 PMQuote from: rfmwguy on 06/24/2015 03:41 PMQuote from: SeeShells on 06/24/2015 03:33 PMQuote from: Rodal on 06/24/2015 02:51 PMOn Google Chrome the T animation works fine in color (if one clicks the image). I cannot get the B&W T animation to work on Google Chrome. It freezes.The pattern (for the color animation) never settles down to the symmetric standing wave TE11 pattern (it wants to, but the peak that should be at the center, is instead to the left):wonder whether this is due to not reaching steady-state yet (not enough finite difference time steps have been marched) or whether it is the asymmetric effect of the antenna that is never going to dissapear////////////////One can see the fractal artifact due to the discrete Finite Difference mesh: the fractal artifact is all over at the beginning but it disappears after a while and the fractal artifact only persists at the circular boundary (due to the difficulty of the finite difference mesh to satisfy the boundary conditions on a circular boundary using a Cartesian coordinate system: the Boundary Conditions are only satisfied at the finite difference mesh gridpoints)It looks like the mode tries to stabilize in the center but the wave energy from the antenna migrating from the side antenna mount pushes and deforms it into the side walls. I can only watch this a couple of times before I want to get my hip huggers, tie dye t-shirts and platform shoes out again. Shell, what is your guess at the best antenna placement, centralized along longitudinal axis? 1/4 up from big end? 1/4 up from small? midway? Polarity perpendicular to longitudinal axis?I can locate my antenna anywhere, just thought I'd ask you and others opinion about 1st locale.It seems like placing the antenna along the longitudinal axis of symmetry would ensure transverse symmetry. I don't see why doing this would harm any thrust force (if there is any), and being off axis would be detrimental.As to the optimal location on the longitudinal axis (how close to the big base) that depends on the mode shape excited, which depends on the frequency and the geometrical shape of the frustum. One would have to run separate MEEP runs with the antenna in different locations for your geometry, to see where it maximizes the amplitude of the mode shape.The mode shapes do NOT have equi-wavelength along the axis (take a gander at my report, the wave pattern is NOT sinusoidal), the half-wavelength increases towards the small base, hence optimal placement of the antenna is not trivial.0.158750 sd0.279654 bd0.251714 L2.450 ghzif anyone would be so kind as to meep me...

Quote from: rfmwguy on 06/24/2015 03:55 PMQuote from: Rodal on 06/24/2015 03:47 PMQuote from: rfmwguy on 06/24/2015 03:41 PMQuote from: SeeShells on 06/24/2015 03:33 PMQuote from: Rodal on 06/24/2015 02:51 PMOn Google Chrome the T animation works fine in color (if one clicks the image). I cannot get the B&W T animation to work on Google Chrome. It freezes.The pattern (for the color animation) never settles down to the symmetric standing wave TE11 pattern (it wants to, but the peak that should be at the center, is instead to the left):wonder whether this is due to not reaching steady-state yet (not enough finite difference time steps have been marched) or whether it is the asymmetric effect of the antenna that is never going to dissapear////////////////One can see the fractal artifact due to the discrete Finite Difference mesh: the fractal artifact is all over at the beginning but it disappears after a while and the fractal artifact only persists at the circular boundary (due to the difficulty of the finite difference mesh to satisfy the boundary conditions on a circular boundary using a Cartesian coordinate system: the Boundary Conditions are only satisfied at the finite difference mesh gridpoints)It looks like the mode tries to stabilize in the center but the wave energy from the antenna migrating from the side antenna mount pushes and deforms it into the side walls. I can only watch this a couple of times before I want to get my hip huggers, tie dye t-shirts and platform shoes out again. Shell, what is your guess at the best antenna placement, centralized along longitudinal axis? 1/4 up from big end? 1/4 up from small? midway? Polarity perpendicular to longitudinal axis?I can locate my antenna anywhere, just thought I'd ask you and others opinion about 1st locale.It seems like placing the antenna along the longitudinal axis of symmetry would ensure transverse symmetry. I don't see why doing this would harm any thrust force (if there is any), and being off axis would be detrimental.As to the optimal location on the longitudinal axis (how close to the big base) that depends on the mode shape excited, which depends on the frequency and the geometrical shape of the frustum. One would have to run separate MEEP runs with the antenna in different locations for your geometry, to see where it maximizes the amplitude of the mode shape.The mode shapes do NOT have equi-wavelength along the axis (take a gander at my report, the wave pattern is NOT sinusoidal), the half-wavelength increases towards the small base, hence optimal placement of the antenna is not trivial.0.158750 sd0.279654 bd0.251714 L2.450 ghzif anyone would be so kind as to meep me...Does this look like your cavity?