You can read DonVK's workaround's here Acoustic Horn Design – The Easy Way (Ath4)
or just download ABEC and avoid the issue entirely 🙂
ABEC3 - Professional Version
or just download ABEC and avoid the issue entirely 🙂
ABEC3 - Professional Version
There is seemingly a bug in the version 4.7.2. 2x2n.gpl, the new Results plotter, wants some file named static.txt, which is nowhere to be found. Previous plotter, report2.gpl, does not request this file, so as a workaround I commented "load static.txt", adn it worked.
Otherwise, thanks for the great design tool, Mabat!
Otherwise, thanks for the great design tool, Mabat!
I don't use AKABAK myself yet, there are also some other issues. As I'm still more than happy with the old ABEC, I don't have a reason to go into that.
(When creating a report, gnuplot is run in the 'Results' directory, where are also all the input data files stored as TXT files. Those are written when Ath is executed with the '-r' parameter - they are extracted from the file 'Spectrum_ABEC.txt' which is the output file saved in ABEC.)
The file 'static.txt' is written in the 'Results' directory under the ABEC project directory when you run Ath. It contains additional information about the project. The other file created in the same directory is 'coords.txt' which contains profile coordinates for the report. If it's not there, something went wrong. Without these files the report won't be complete.
(When creating a report, gnuplot is run in the 'Results' directory, where are also all the input data files stored as TXT files. Those are written when Ath is executed with the '-r' parameter - they are extracted from the file 'Spectrum_ABEC.txt' which is the output file saved in ABEC.)
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Hm, strange. I am using ABEC too, 3.6.0 b7, and for some reason it does not transfer (or calculate?) SPL_H to VACS. Those problems may be related.
Clean install, tried with demo1 and demo6.
Attaching screenshots of ABEC, VACS and results file list. Is there something else I should do to troubleshoot?
Clean install, tried with demo1 and demo6.
Attaching screenshots of ABEC, VACS and results file list. Is there something else I should do to troubleshoot?
Attachments
I didn't go through the demos yet with 4.7.2, there may be something wrong as the reporting changed a bit in the meantime. I recommnend not to start with the demos this time.
- Ah, I see the issue now. In the script file there must be a 'Report' item defined, even if empty, otherwise the 'static.txt' file is not written:
Report = {
}
(Note that you can modify the report properties with this item.)
- Ah, I see the issue now. In the script file there must be a 'Report' item defined, even if empty, otherwise the 'static.txt' file is not written:
Report = {
}
(Note that you can modify the report properties with this item.)
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DonVK also talks about a "solver.txt" file where we have to make changes, but I have no idea where to find it. Apparently it should be located in the ABEC_InfiniteBaffle directory, but i have no file like this unfortunately.
Yes I could download ABEC, but I'm used to Akabak and apparently DonVK made it work on Akabak
Does your Ath.exe run successfully?
If you don't see this after you run it with your config, you should probably check the manual.
If you don't see this after you run it with your config, you should probably check the manual.
It is solving.txt, inside the ABEC project created it should look like this
Akabak works differently enough to make the script import difficult and having to reorient the planes every time is painful. What you choose is up to you but Ath is setup to work perfectly with ABEC no effort is required.
Attachments
Btw, in case somebody was wondering..
I tried to do a simple divider "lens" for a 2" horn to see if it will improve the HF spread. It didn't.
Measurement is taken 30 degrees of axis. Red is with the lens, Blue is without.
I tried to do a simple divider "lens" for a 2" horn to see if it will improve the HF spread. It didn't.
Measurement is taken 30 degrees of axis. Red is with the lens, Blue is without.
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Yeah, it doesn't work like this, that would be too easy. I'm close to a point where I can start simulating but I've just found out that ABEC has some problems with subdomains in the CircSym mode. It seems that AKABAK doesn't, so maybe this will be the reason to switch to AKABAK at last. To me it's still a step backwards, I really like the manual scripting approach, but if it's the only way to simulate it, what can I do. Fortunately, it seems that it's possible to generate the scripts so that it's still ABEC compatible and also importable to AKABAK at the same time.
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Those literate in ABEC, is there anything wrong with this script? It gives a very different result than if calcualted as only a single exterior subdomain. Am I doing something wrong or is this just how it is? I really hope I made a mistake I can't see, that would save me a lot of time... 😱
Attachments
Interior is the default, but yes, that doesn't make a difference. 🙁
Code:
Control_Solver
f1=200; f2=20000; NumFrequencies=100
Abscissa=log; Dim=CircSym; MeshFrequency=60000
Nodes "Nodes"
Scale=1mm
1 0 12
2 20 12
3 40 12
4 40 18
5 -5 18
6 -5 0
7 0 0
8 20 0
Subdomain_Properties "S1"
Subdomain=1; ElType=Interior
Subdomain_Properties "S2"
Subdomain=2; ElType=Exterior
Elements "Source"
RefNodes="Nodes"
Subdomain=1
1 7 1
Elements "Tube1"
RefNodes="Nodes"
Subdomain=1
1 1 2
Elements "Interface"
RefNodes="Nodes"
Subdomain=1,2
1 2 8
Elements "Tube2"
RefNodes="Nodes"
Subdomain=2
1 2 3
2 3 4
3 4 5
4 5 6
Driving
DrvGroup=1001
RefElements="Source"
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Hmm, I as far as I remember, BEM uses Sommerfield radiation condition to calculate exterior radiation problem, whereas interior radiation problem uses Neumann/Dirichlet boundary condition. Maybe this one somehow affects the result of calculations of Exterior-only vs exterior-interior formulation 
According to the documentation adding subdomains should cause no difference, only make the calculations more stable. They even give an example of a "waveguide with fins" as a suitable scenario. Perhaps it's only the CircSym mode that has this problem, I have no problem believing that a full 3D mesh would work better, it's only something I'd like to avoid if possible.
I'm not sure which direction the normal of the domain should be pointing..
Btw I found out how to export 2d drawings from Fusion to the circ-sym mode in AKABAK.
1. Extrude your sketch onto a surface and then project onto a new sketch.
2. Use the addin Splines as Polylines to export the new sketch to DXF.
I'm also currently trying to rig the meander sketch onto an infinite baffle.
EDIT: sometimes a couple of lines go missing in translation 🙁 I think this is an issue in AKABAK
Btw I found out how to export 2d drawings from Fusion to the circ-sym mode in AKABAK.
1. Extrude your sketch onto a surface and then project onto a new sketch.
2. Use the addin Splines as Polylines to export the new sketch to DXF.
I'm also currently trying to rig the meander sketch onto an infinite baffle.
EDIT: sometimes a couple of lines go missing in translation 🙁 I think this is an issue in AKABAK
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I suppose, that subdomains does not influences the interior radiation problem (we can divide the closed volume into as many subdomains as we need). But I'm not sure that we will get the correct result if we replace the problem of internal radiation with the problem of external radiation.
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But we do this all the time in the case of an infinite baffle. There are also interior and exterior subdomains with an interface in between. It definitely worked in a 3D case. I'm not sure about the CircSym.
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