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JIF

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JIF last won the day on December 27 2017

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About JIF

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  1. Thanks for the file. Please change the file by replacing (line 2) setEnv([[FEKO_USER_HOME__SETUP]], [[%APPDATA%\feko\2018.0_]]..getEnv([[FEKO_INSTALLPATH_HASH__SETUP]]), true); with setEnv([[FEKO_USER_HOME__SETUP]], [[c:\temp\feko\2018.0_]]..getEnv([[FEKO_INSTALLPATH_HASH__SETUP]]), true); This will avoid the use of %APPDATA% that I suspect has a non-ASCII character in it (probably your user name on the PC includes a non-ASCII character). You have installed FEKO into the "Program Files" folder (nothing wrong with that and it is the default) and Windows (not FEKO) requires admin rights to edit files in the "Program Files" folder. I think that is what you are referring to when you say that you don't have permission to change the file.
  2. Hello Pawel Sorry, I requested FEKOenvironment.lua, but that was a mistake on my side. I should have asked for FEKOenvironmentFromSetup.lua instead (located in the same folder). Why? Line 66 is the following: setEnv("FEKO_USER_HOME", (getEnv("FEKO_USER_HOME__SETUP") or [[%APPDATA%\feko\%FEKO_VERSION%]]), OVERWRITE) As you can see, the line is trying to set the value of FEKO_USER_HOME (where configuration settings and logs are stored) by either using the value of FEKO_USER_HOME__SETUP (set in FEKOenvironmentFromSetup.lua) or using the value of %APPDATA%. Thus, I need to see FEKOenvironmentFromSetup.lua to see if something is not correctly. The alternative could be to change the line in FEKOenvironmentFromSetup.lua that sets FEKO_USER_HOME__SETUP to point to a folder that definitely does not contain unicode characters. Below is an example line that you can use instead of the one that you currently have in FEKOenvironmentFromSetup.lua (you may have to create the C:\temp folder). setEnv([[FEKO_USER_HOME__SETUP]], [[c:\temp\feko\2018.0_]]..getEnv([[FEKO_INSTALLPATH_HASH__SETUP]]), true); Let me know if this solves your problem. I hope it helps.
  3. Hello Pawel, This is probably the same problem as described in: The problem most likely that %APPDATA% points to a directory that uses a unicode (non-ASCII) character that we don't currently support. If you don't manage to fix the problem with the details on the forum topic mentioned, please attach the FEKOenvrionment.lua file so that we can help you (the path to the file is shown in your screenshot).
  4. There is no easy way to just "not sample on segment vertices", but the near field request has an option to "sample on edges" or not and this moves the sample points by half a increment. Depending on your model, that could be the quickest way to avoid these points.
  5. JIF

    Antenna feed gap capacitance

    Hello EMCanuck1, Voltage sources can be added on segments (vertex port or segment port) or on the edge between triangle faces (edge port) or on microstrip ports (not applicable for your question). Are you referring to a segment / wire port or a edge port? For wires, there are segment ports and vertex ports. A segment port applies the voltage over the length of the segment that has the voltage source, while the vertex port applies the voltage between segments with a "zero length gap". In both cases FEKO does not add additional capacitance. The difference between the two will be dominated (when applicable) by the difference in phase due to the difference in the voltage source position (difference in the length of the gap). For edge ports (if you are modelling the antenna as a cylinder), no additional capacitance is added either and the voltage source is applied on the boundary of the two faces. If you have more questions, please add some pictures or models so that we can better understand what you are referring to with your question.
  6. Hello shashank119, Warning 88 has been removed since FEKO now detects these triangle singularities and changes the integration strategy to use a singularity cancellation routine. Thus, warning 88 is only applicable to older versions. Regarding warning 81, the text description is "Singular field on the axis of a segment" and thus it applies to segments, not triangles. I assume you are requesting the a near field value on the axis of a wire segment and there the field is singular. I would suggest that you move your near field request point away from the segment to avoid the warning. Again, I would not sample too close to the segment either (a distance equal to the length of the segment is safe, but I have not done an accuracy study in order to provide more details regarding the recommended sample distance).
  7. JIF

    Transmission/ Reflection Co-efficient in FEKO.

    Hello Sourabh13, Yes, your understanding is correct.
  8. JIF

    Error In Feko

    Hello Sra, The windscreen method was developed to model antennas embedded in windscreens and one of the assumptions are that the windscreen is relatively flat, but still curved. This error is given when two triangles in a windscreen reference face have normals that are separated by more than 90 degrees and thus probably have too much curvature for the assumptions used in the windscreen solution method. Without the model, I'm not able to confirm this or comment further on the applicability of the windscreen solution method to your model.
  9. JIF

    FEKO Blockage analysis

    Hello shashank119, I understand the request, but this is not currently possible in FEKO, but has been requested and should be available in the future.
  10. JIF

    Import ERROR Feko

    Hello Pawel, The student edition of FEKO does not support geometry import or export - see https://altairuniversity.com/feko-student-edition/. You can import and export Parasolid, since that is the native format used in FEKO. If you can export a Parasolid file, you will be able to import it into FEKO.
  11. JIF

    Antenna Simulation on a platform

    Hi ben, You are correct; when triangles intersect or don't align where they touch, FEKO will give an error. FEKO 2018 has improved mesh checking in the solver and thus it is more likely to detect the intersecting / overlapping elements. You need to correct your model to ensure valid mesh connections. This is required in the MoM since basis functions need to created over triangles and this requires a valid mesh.
  12. I suspect it should be: !"C:\Program Files\Altair\2017\feko\bin\cadfeko.exe" --run-script BuildModelAndSimulate.lua --non-interactive Note that I have put quotes around the application and in your prefeko example and the rest is passed as a parameter as that seems to be what you did for "filename.pre".
  13. I already provided the details in my previous comment. If you don't need to change the name of the stl or cfx file, then the command (in a FEKO terminal) would simply be: cadfeko --run-script BuildModelAndSimulate.lua --non-interactive You should be able to run CADFEKO (or the command above) from Matlab, but then you will have to use the full absolute path to the cadfeko application binary (since the environment won't be setup inside Matlab). I don't have access to Matlab, but I know many users have called FEKO components from external applications, including Matlab. I hope this answers your question. For extracting the data, you may want to consider a Lua script for POSTFEKO to write the data that you want to disk. See
  14. What you are trying to do is very easily possible, but there are many ways to do the same thing and I'll pick one (maybe not the one that works best for you). The Lua scripts are CADFEKO (or POSTFEKO) scripts and thus you need to use them in CADFEKO (or POSTFEKO), not runfeko. The runfeko application will take a FEKO model (either a *.cfx file, *.pre file or *.fek file) and performs the simulation. FEKO only understand *.fek files, but runfeko knows what to do with *.cfx and *.pre files to create the *.fek file and then run FEKO (that produces the *.bof, *.out and many other files). I looked at your recording and most of it is fine, but there are a few problems and the crucial bit is missing. Firstly, since you are creating the mesh in an external application and then importing it, there is no reason to remesh in CADFEKO, so I removed that section. The crucial bit that you missed is that you also need to define the layered dielectric (in your case, just a single 0.6 um layer of Graphene) and then apply it to the imported face. I have adjusted the script accordingly (this is similar to what I did previously with your *.pre file). You have a few options, you could either create a script that creates the and saves the CADFEKO model (*.cfx) and then run runfeko on that model or (as you did), launch runfeko from withing CADFEKO (in the script). I would probably rather split the two (create CADFEKO model and run the solver), but for now I decided to just stick with your script and run it from CAFEKO. Here is the modified script: BuildModelAndSimulate.lua. As I have mentioned, you need to run the script in CADFEKO, but that does not mean that you have to click it manually. You can run CADFEKO in non-interactive mode from command line or an external application. Here is an example: cadfeko --run-script BuildModelAndSimulate.lua --non-interactive --configure-script "modelName='testName.cfx' ; stlName='graph_001.stl'" | more As you can see, it runs CADFEKO, provides the script that CADFEKO should execute, ensures that the GUI does not display (if you remove this, CADFEKO will remain open after the script has completed, but with this option it will close once completed) and then it also passes some configuration (just normal Lua code that is executed before the script execution starts) and finally the output (stdout) is piped to more (I added this so that I can see errors in the script since GUI applications don't write to the console in Windows - in Linux this is not required). As part of the script, the solver will also be run, but as I mentioned, if I had to do this, I would remove that from the script and do a second call to runfeko instead (I'll leave that simple change to you). With the steps above, you can adjust the name of the stl file to import and the name of the resulting model and thus it easily fits into any automated system. For reference, here are the results (0.6 um Graphene compared to PEC): It is not the same as your graph, but after changing the *.pre file to also use 0.6 um Graphene, the results match perfectly (as expected). Yes, 0.001 was the thickness. If you change it to 0.6, you get the results above? I don't want to explain each parameter, since it is not required. When you are on a card in EDITFEKO, press F1 and then modify the parameters in the panel. The same goes for the 4 and the -1 of the SK card - don't worry about them and use the panel and they will be adjusted to the correct values corresponding to the options selected and entered in the panel.
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