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Here's what I think is causing the EMDrive to work: it's a bug in the functioning of the universe. If you have a photon bouncing between the same two points, the bug is symmetrical. The EMDrive effect does not show up in a symmetrical resonance cavity. Start bouncing light around a non-symmetrical cavity,and the rounding error can compound.
...Which is exactly eqn (14). So, according to McCulloch, and a direct result of the linearity of Maxwell's equations, the force from an EM drive is constant, no matter the size of the device.I'll let someone else check Shawyer's and other force equations. If McCulloch and my conclusions are correct there are a couple of ramifications. 1) The force from a single EM drive is fixed, but the force from an array of EM drives is linear in the number of drives per given area of big bases of the drives. 2) Square bases have a better form factor per given area, so someone needs to look at a Square Pyramid frustum for an EM drive effect. Is there significant mutual interference between EM drives packed closely together? Layered?
Quote from: aero on 10/05/2015 06:18 pm...Which is exactly eqn (14). So, according to McCulloch, and a direct result of the linearity of Maxwell's equations, the force from an EM drive is constant, no matter the size of the device.I'll let someone else check Shawyer's and other force equations. If McCulloch and my conclusions are correct there are a couple of ramifications. 1) The force from a single EM drive is fixed, but the force from an array of EM drives is linear in the number of drives per given area of big bases of the drives. 2) Square bases have a better form factor per given area, so someone needs to look at a Square Pyramid frustum for an EM drive effect. Is there significant mutual interference between EM drives packed closely together? Layered?Interesting bit of data. Raise the frequency, make it inverse proportionally smaller and get the same thrust per power (if it really exists, which seem more likely experiment after experiment). That would certainly help to make them into arrays, for multiplying the thrust.Could we have infrared cavities (up to 1 mm sized)?I imagine visible light cavities would be quite microscopic and possibly unfeasible (visible light having a wavelength in the few hundred nanometers).
But why stop now, I'm on a roll ... We have all of these different cavities already. Here: Normalized Length Big dia Small dia. L wb ws ~FM Shawyer Demo 0.187 0.28 0.14921 1 1.5 0.8 -0.095 Shawyer flt. 0.1386 0.2314 0.1257 1 1.67 0.92 -0.088 rfmwguy 9.91 in. 11.01 in.ID 6.25 in ID 1 1.11 0.63 -0.1 Yang-Shell 0.24 0.201 0.1492 1 0.8375 0.62 -0.052 SeeShell CE2 0.1634 0.2950 0.1600 1 1.8 0.98 -0.08Well now - isn't that interesting? While the normalized cavity dimensions are all over the grid, the figure of merit is very clustered. And yes, the Yang-Shell model is an outlier, unfortunately, not to the high side.The highest FM calculated in the grid is -0.6 for L=1, wb = 2 and ws = 0.1, but there are other candidates. For example, L = 1, wb = 1.0, ws = 0.1 gives FM = -0.5, and L = 1, wb = 1.4, ws = 0.2 gives FM = -0.4, and L = 1, wb = 1.4, ws = 0.3 gives FM = -0.3.There are other candidates, I'll just attach my spreadsheet for those interested.
Quote from: SteveD on 10/05/2015 03:02 amHere's what I think is causing the EMDrive to work: it's a bug in the functioning of the universe. If you have a photon bouncing between the same two points, the bug is symmetrical. The EMDrive effect does not show up in a symmetrical resonance cavity. Start bouncing light around a non-symmetrical cavity,and the rounding error can compound. I love the notion that it might work by accumulating rounding errors. We know there are step functions in the energy levels of electron shells in atoms - and this could/would tie into them as well, wouldn't it? Collecting rounding errors is one of my favorite bank robbery techniques, and it would be nice to see it make an appearance in the physical/quantum world.
Quote from: aero on 10/05/2015 10:05 pmBut why stop now, I'm on a roll ... We have all of these different cavities already. Here: Normalized Length Big dia Small dia. L wb ws ~FM Shawyer Demo 0.187 0.28 0.14921 1 1.5 0.8 -0.095 Shawyer flt. 0.1386 0.2314 0.1257 1 1.67 0.92 -0.088 rfmwguy 9.91 in. 11.01 in.ID 6.25 in ID 1 1.11 0.63 -0.1 Yang-Shell 0.24 0.201 0.1492 1 0.8375 0.62 -0.052 SeeShell CE2 0.1634 0.2950 0.1600 1 1.8 0.98 -0.08Well now - isn't that interesting? While the normalized cavity dimensions are all over the grid, the figure of merit is very clustered. And yes, the Yang-Shell model is an outlier, unfortunately, not to the high side.The highest FM calculated in the grid is -0.6 for L=1, wb = 2 and ws = 0.1, but there are other candidates. For example, L = 1, wb = 1.0, ws = 0.1 gives FM = -0.5, and L = 1, wb = 1.4, ws = 0.2 gives FM = -0.4, and L = 1, wb = 1.4, ws = 0.3 gives FM = -0.3.There are other candidates, I'll just attach my spreadsheet for those interested.Actually mine moved up to 10.2 in. Length from 9.91
Quote from: rfmwguy on 10/05/2015 10:17 pmQuote from: aero on 10/05/2015 10:05 pmBut why stop now, I'm on a roll ... We have all of these different cavities already. Here: Normalized Length Big dia Small dia. L wb ws ~FM Shawyer Demo 0.187 0.28 0.14921 1 1.5 0.8 -0.095 Shawyer flt. 0.1386 0.2314 0.1257 1 1.67 0.92 -0.088 rfmwguy 9.91 in. 11.01 in.ID 6.25 in ID 1 1.11 0.63 -0.1 Yang-Shell 0.24 0.201 0.1492 1 0.8375 0.62 -0.052 SeeShell CE2 0.1634 0.2950 0.1600 1 1.8 0.98 -0.08Well now - isn't that interesting? While the normalized cavity dimensions are all over the grid, the figure of merit is very clustered. And yes, the Yang-Shell model is an outlier, unfortunately, not to the high side.The highest FM calculated in the grid is -0.6 for L=1, wb = 2 and ws = 0.1, but there are other candidates. For example, L = 1, wb = 1.0, ws = 0.1 gives FM = -0.5, and L = 1, wb = 1.4, ws = 0.2 gives FM = -0.4, and L = 1, wb = 1.4, ws = 0.3 gives FM = -0.3.There are other candidates, I'll just attach my spreadsheet for those interested.Actually mine moved up to 10.2 in. Length from 9.91Ok - I remember that now. Just an older data list not totally updated. NSF-1701 10.2 in. 11.01 in.ID 6.25 in ID 1 1.08 0.613 -0.1-That did increase the magnitude of FM a little bit but I need a better method of interpreting the data in order to read it more closely. Maybe 10 times as many rows and columns ... Or a more efficient presentation. The point I get from the data table is that the FM is quite sensitive to bw, not so much to sw. FM is just very small when sw/L gets into the range we have been working with. It seems to show that the frustums need to be more pointy. Didn't we already conclude that?
Go ahead and pollute my punch bowl but it better be something tasty. I think he was referring how to get the heat generated by the magnetron away from the frustum. If the power supply and the magnetron are lets say 1 meter away and the RF is fed via coax to either antennas or a waveguide the only heat you would be dealing with would be the heat from the actions in the frustum.
Quote from: SeeShells on 10/05/2015 04:55 pmGo ahead and pollute my punch bowl but it better be something tasty. I think he was referring how to get the heat generated by the magnetron away from the frustum. If the power supply and the magnetron are lets say 1 meter away and the RF is fed via coax to either antennas or a waveguide the only heat you would be dealing with would be the heat from the actions in the frustum.You are correct Shell, I was only trying to think of ways to remove as much heat from the immediate site of the test as possible. Frustum will obviously still get hot, but presumably not as hot as the magnetron itself? I put a question mark because I honestly have no idea and am not qualified to make any remark on the topic. I also was wondering then if you do move the magnetron away and you transfer the output via conduit, at that point you'd have the magnetron fixed stationary on to something, but then there would be some weight to the conduit itself, do you suspend that some way to prevent that from interfering with these very minute measurements of movement?Thanks again for entertaining the layman questions.
Quote from: JonathanD on 10/06/2015 02:06 amQuote from: SeeShells on 10/05/2015 04:55 pmGo ahead and pollute my punch bowl but it better be something tasty. I think he was referring how to get the heat generated by the magnetron away from the frustum. If the power supply and the magnetron are lets say 1 meter away and the RF is fed via coax to either antennas or a waveguide the only heat you would be dealing with would be the heat from the actions in the frustum.You are correct Shell, I was only trying to think of ways to remove as much heat from the immediate site of the test as possible. Frustum will obviously still get hot, but presumably not as hot as the magnetron itself? I put a question mark because I honestly have no idea and am not qualified to make any remark on the topic. I also was wondering then if you do move the magnetron away and you transfer the output via conduit, at that point you'd have the magnetron fixed stationary on to something, but then there would be some weight to the conduit itself, do you suspend that some way to prevent that from interfering with these very minute measurements of movement?Thanks again for entertaining the layman questions. You are far from a layman. Anyone here disagree? No? See. One time I entertained of putting the magnetron onto the top of the frustum with dual waveguide injectors although the weight, costs and the logistics of doing so killed that idea. Now I'm doing a magnetron into a waveguide to antenna in the center section of the test stand and then run coax out to antennas on the top small plate. Or I can do antennas to waveguide into the frustum. Mainly I'm looking to remove as much heat from the frustum and allow two methods to test. Controlled TE xx mode through the top small plate with antennas or highly symmetrical waveguides injecting into the side walls. I'm building for both options.I believe I can ramp up the inverter to run the magnetron up to 2 KW although that will be further down the line. If it doesn't all sync and give me a great SWR it will kill the test with heat. That process will be a slower one but could allow for a respectable input of power into the frustum after it's "tuned up".I so wanted to have this fired up this week for a birthday present to me but I don't think I'll make it. dang!Shell
Quote from: Silversheep2011 on 10/05/2015 11:04 amForgot to mention a caution Consider FIRE HAZARD if gets to hot!Interesting...ok, now for the big question...interested in building one for me to test?
Forgot to mention a caution Consider FIRE HAZARD if gets to hot!
Quote from: rfmwguy on 10/05/2015 02:19 pmQuote from: Silversheep2011 on 10/05/2015 11:04 amForgot to mention a caution Consider FIRE HAZARD if gets to hot!Interesting...ok, now for the big question...interested in building one for me to test?You know what funny enough I am,need to do a size up first on time and effort, verses other commitments of course.I think I can find a microwave at the junk yard or sacrifice the old one in the kitchen in the 'name of science and the common good for mankind' and argue its almost due for replacing although it works just fine. It's going to be the digital logging gear parts -that’s the killer $’s isn't it?Going to be thinking the next few days about it, and see if there is a simpler and better work around?rfmwguy most or us would probably like to know how much time and effort have you spent on project so far? 100, 500, maybe a 1000 hours? First time builds I imagine lots of setup time and fiddling, and if you had to do a repeat and a second time now the build 1/2 that time?