The link to the outside (or to some outside field) is of paramount importance, otherwise it will not move (maybe just explode )
Quote from: Rodal on 07/18/2015 08:34 pmThe link to the outside (or to some outside field) is of paramount importance, otherwise it will not move (maybe just explode )Hasn't that always been the fundamental problem needing a solution?
Dr. Rodel,Attached is a screen shot of a corner of the .h5 file for SeeShell's model. It illustrates the problem of accurately locating the inside corner of the big end of the frustum. No such problem at the small end.
Ref TheTraveller Post #4570I don't know your critical specs, so I don't know if these are 'better' or not:Insulated Wire: http://www.iw-microwave.com/cable_specsThe cable series numbers are their nominal diameter in mils. To get specs for a specific cable just click on the cable number. The 280 series provides around .25 dB/m @ 2.5 GHz and will handle around 1 kw, for example.IW brags about their low insertion loss but the ones I have used tend to be relatively stiff for a given diameter.Or W. L. Gore: http://tools.gore.com/gmcacalc/#/The Gore link is to their cable calculator, which provides specs for connectorized cables of the length specified at the freq of interest. ( .32 db/1 m @ 2.5 GHz, with a power rating of 1532 watts, for example.)Gore is known for extreme flexibility, low insertion loss, good VSWR, and tolerance for small radius bends They also define the term 'expensive cables'.
Quote from: aero on 07/18/2015 09:29 pmDr. Rodel,Attached is a screen shot of a corner of the .h5 file for SeeShell's model. It illustrates the problem of accurately locating the inside corner of the big end of the frustum. No such problem at the small end.I'm not stirring the pot here but asking if anyone you know or anyone here of has looked at this program running in Linux written in C? http://www.met.reading.ac.uk/clouds/maxwell/
Quote from: BL on 07/18/2015 10:00 pmRef TheTraveller Post #4570I don't know your critical specs, so I don't know if these are 'better' or not:Insulated Wire: http://www.iw-microwave.com/cable_specsThe cable series numbers are their nominal diameter in mils. To get specs for a specific cable just click on the cable number. The 280 series provides around .25 dB/m @ 2.5 GHz and will handle around 1 kw, for example.IW brags about their low insertion loss but the ones I have used tend to be relatively stiff for a given diameter.Or W. L. Gore: http://tools.gore.com/gmcacalc/#/The Gore link is to their cable calculator, which provides specs for connectorized cables of the length specified at the freq of interest. ( .32 db/1 m @ 2.5 GHz, with a power rating of 1532 watts, for example.)Gore is known for extreme flexibility, low insertion loss, good VSWR, and tolerance for small radius bends They also define the term 'expensive cables'.I have a quote coming from Gore, I suspect your right they are not cheap.
Quote from: SeeShells on 07/18/2015 10:02 pmQuote from: aero on 07/18/2015 09:29 pmDr. Rodel,Attached is a screen shot of a corner of the .h5 file for SeeShell's model. It illustrates the problem of accurately locating the inside corner of the big end of the frustum. No such problem at the small end.I'm not stirring the pot here but asking if anyone you know or anyone here of has looked at this program running in Linux written in C? http://www.met.reading.ac.uk/clouds/maxwell/Seems to only solve solutions to Maxwell's equations in a 2D domain (using the Finite-Difference Time-Domain method) not 3D. As such it would model the truncated cone as a perfectly flat sheet with trapezium boundaries. The azimuthal electromagnetic field vectors would become scalar dots in such a model.
Quote from: SeeShells on 07/18/2015 10:05 pmQuote from: BL on 07/18/2015 10:00 pmRef TheTraveller Post #4570I don't know your critical specs, so I don't know if these are 'better' or not:Insulated Wire: http://www.iw-microwave.com/cable_specsThe cable series numbers are their nominal diameter in mils. To get specs for a specific cable just click on the cable number. The 280 series provides around .25 dB/m @ 2.5 GHz and will handle around 1 kw, for example.IW brags about their low insertion loss but the ones I have used tend to be relatively stiff for a given diameter.Or W. L. Gore: http://tools.gore.com/gmcacalc/#/The Gore link is to their cable calculator, which provides specs for connectorized cables of the length specified at the freq of interest. ( .32 db/1 m @ 2.5 GHz, with a power rating of 1532 watts, for example.)Gore is known for extreme flexibility, low insertion loss, good VSWR, and tolerance for small radius bends They also define the term 'expensive cables'.I have a quote coming from Gore, I suspect your right they are not cheap.A 4' Gore-Tex cable terminated in type N connectors ran about $400... In the mid 1990's.You should be sitting down when you open the quote.
Quote from: Rodal on 07/18/2015 10:05 pmQuote from: SeeShells on 07/18/2015 10:02 pmQuote from: aero on 07/18/2015 09:29 pmDr. Rodel,Attached is a screen shot of a corner of the .h5 file for SeeShell's model. It illustrates the problem of accurately locating the inside corner of the big end of the frustum. No such problem at the small end.I'm not stirring the pot here but asking if anyone you know or anyone here of has looked at this program running in Linux written in C? http://www.met.reading.ac.uk/clouds/maxwell/Seems to only solve solutions to Maxwell's equations in a 2D domain (using the Finite-Difference Time-Domain method) not 3D. As such it would model the truncated cone as a perfectly flat sheet with trapezium boundaries. The azimuthal electromagnetic field vectors would become scalar dots in such a model. Ahh that makes sense I knew it was a 2D program using the FDTD method but didn't figure on the vectors we need becoming dots and unusable. Thanks Doc!
Hello,I've been tinkering around with meep on Debian, and I have a procedure for installing meep 1.3 on Debian 8, which packages the older meep 1.2 by default:# apt-get install h5utils openmpi-bin# apt-get build-dep meep-openmpiThis installs everything we'll need for dependencies, but by default ./configure won't find libhdf5, so we need to do this.# cd /usr/lib/x86_64-linux-gnu/# ln -s libhdf5_openmpi.so libhdf5.so# export CPPFLAGS="-I/usr/include/hdf5/openmpi"Now we can head back to our source-building directory and get on with it.# wget http://ab-initio.mit.edu/meep/meep-1.3.tar.gz# cd meep-1.3# ./configure --with-mpi --prefix=$HOMEObviously this assumes $HOME is in your path, you can install it wherever.# make# make installIf anyone has meep files that they lack the time to process on their own hardware, I have a reasonably powerful system that can crank through a 12-thread run of NSF-1701.ctl in about 40 minutes, as well as a web server (nginx) running so I can package the output files (h5, csv, png, whatever) and provide a link. I'm a sysadmin by trade, and the last physics I took was Newton, so I don't yet know enough to write my own Scheme scripts for meep and get any meaningful output.Yes, for those wondering, I'm also tidux on /r/emdrive.
Quote from: SeeShells on 07/18/2015 10:21 pmQuote from: Rodal on 07/18/2015 10:05 pmQuote from: SeeShells on 07/18/2015 10:02 pmQuote from: aero on 07/18/2015 09:29 pmDr. Rodel,Attached is a screen shot of a corner of the .h5 file for SeeShell's model. It illustrates the problem of accurately locating the inside corner of the big end of the frustum. No such problem at the small end.I'm not stirring the pot here but asking if anyone you know or anyone here of has looked at this program running in Linux written in C? http://www.met.reading.ac.uk/clouds/maxwell/Seems to only solve solutions to Maxwell's equations in a 2D domain (using the Finite-Difference Time-Domain method) not 3D. As such it would model the truncated cone as a perfectly flat sheet with trapezium boundaries. The azimuthal electromagnetic field vectors would become scalar dots in such a model. Ahh that makes sense I knew it was a 2D program using the FDTD method but didn't figure on the vectors we need becoming dots and unusable. Thanks Doc!It would be an approximation to an EM Drive with a rectangular cross section, closer to a rectangular cross section where the cross-sectional width is much longer than the cross-sectional height, so as to have an almost flat field configuration.
Quote from: tidux on 07/18/2015 03:18 pmHello,I've been tinkering around with meep on Debian, and I have a procedure for installing meep 1.3 on Debian 8, which packages the older meep 1.2 by default:# apt-get install h5utils openmpi-bin# apt-get build-dep meep-openmpiThis installs everything we'll need for dependencies, but by default ./configure won't find libhdf5, so we need to do this.# cd /usr/lib/x86_64-linux-gnu/# ln -s libhdf5_openmpi.so libhdf5.so# export CPPFLAGS="-I/usr/include/hdf5/openmpi"Now we can head back to our source-building directory and get on with it.# wget http://ab-initio.mit.edu/meep/meep-1.3.tar.gz# cd meep-1.3# ./configure --with-mpi --prefix=$HOMEObviously this assumes $HOME is in your path, you can install it wherever.# make# make installIf anyone has meep files that they lack the time to process on their own hardware, I have a reasonably powerful system that can crank through a 12-thread run of NSF-1701.ctl in about 40 minutes, as well as a web server (nginx) running so I can package the output files (h5, csv, png, whatever) and provide a link. I'm a sysadmin by trade, and the last physics I took was Newton, so I don't yet know enough to write my own Scheme scripts for meep and get any meaningful output.Yes, for those wondering, I'm also tidux on /r/emdrive.Attempting to follow this on Ubunto, which is, I think, Debian jessie (8.1).I don't wind up with a libhdf5_openmpi.so, but rather x86_64-linux-gnu/libhdf5.so -> libhdf5.so.7.0.0There's no directory /usr/include/hdf5/openmpi, but there is /usr/include/openmpi. The hdf5* files are in /usr/include.meep-1.3 requires libctl version 3.2 or later, but version 3.1 got installed.These don't seem insurmountable, but it sounds like I am not driving against the same repository you are. Can you give me a pointer as to how to update my repository list to match yours for, e.g., meep-openmpi ?Thanks