Elmer Discussion Forum

Thanks for the help friends.

In the end I put in space for the walls of the organ pipe with each side of the wall having its own boundary condition. That seems to work fine although it did complicate the model a lot.

I wanted something like this also. What I did was to write a python script that built a case.sif file for each frequency I wanted to analyze. Then I executed ElmerSolver using the same python script. Then I got a series of output files (*.vtu) -one for each frequency. Paraview would read them in as ...

I am running an electrostatic simulation and the convergence history looks like the attached. It goes down initially but then bounces around. Convergence history.jpg Is this normal? I have also done Helmholtz solutions were the convergence history has decreased monotonically for many orders of magni...

I did a little experimenting and I may know what to do. Instead of a single face separating outside and inside the pipe, I can have 2 faces separating outside and inside. And the space between the faces can be very small, but there is no material between them to connect outside to inside. In this wa...

Thank you very much Peter for the quick and learned reply. I think I don't know how to tell if I am using the same nodes inside and outside the pipe. I will tell you how I generated the geometry and I will show you my results. I suspect I am using the same nodes inside and outside. You can probably ...

I have been working on the problem of an organ pipe in air. Thanks to help form Saint Michael, I got a series of faces to define an organ pipe in a box of air using Salome. Most of the faces of the pipe are very high impedance to simulate a hard surfaces. One face of the pipe injects a pressure wave...

MATCexampleforForum.tar.gz I recreated the Crime and have the results here. Apparently it performed the first analysis correctly and then attempted the next one and gave a segmentation fault. Here is the sif file I used. Header CHECK KEYWORDS Warn Mesh DB "." "." Include Path &q...

Thank you very much Matthias. You said the magic words "put this at the end of your sif file". That was the clue that I was missing. I did try your suggestion. It did not work but now I know how MATC should work. I think I will concentrate on the python solution I mentioned simply because ...

Thank you to Juhani and Cyrille for your kind answers. I studied the situation once more and could not understand how to make MATC work. So I took the other suggestion seriously about scripting the sif file. Rather than using BASH, I decided to do it with python. I wanted to repeatedly run a sif fil...

I would like to repeatedly run ElmerSolver to solve the problem many times with different values of frequency. I have looked very hard to find an example of someone doing this type of automation but I have not seen it. I have looked at the Elmer MATC manual and see the makings of what I need, but I ...