Re: [femm] some proposals for future developments

[David Meeker <dmeeker@xxxxxxxx>]

giovanni.bortolan@xxxxxxxxxxxxx wrote:
>  
> Dear David,
>
> there are few requests from FEMM users for future improvements, so I ask
> for some, hoping they are welcome from other users.
> They are not in a particular order.
> - Are you thinking about a thermal development of BELA? .
I've been thinking about doing current flow and maybe heat conduction
as essentially modified version of the BELA code.  These would be
fairly straightforward to include as additional problem types in the
femm40 program structure.  However, there are some other things that
I'd like to address before doing these new problem types.
>  -
> a Lua log file generated by graphic interaction could give you the
> possibility to make an easy multilevel undo-redo (simply re-executing
> the
> script up to a requested step) and would give us the frame to develop a
> more complex analysis simply adding few lines of scripting.
This would be relatively non-trivial to do.  I suppose that I would
have been a good way to have structured the program if each user
interface command, mouse click, etc. actually called a Lua command. 
Then, it would be easy to make some sort of log.  However, the way that
things are implemented, the Lua commands essentially mirror the
functionality of things that the user does with the keyboard, using a
different set of code to do it.
>  -
> there is a problem in materials library: when I update FEMM version I
> "miss" my own materials. If the library was organised as one directory
> containing many files (one material per file), there would be no problem
> during update.
A good (and fairly easy to implement) addition to the program might be
instead to import a materials library, so that the old and new versions
could be combined without actually having to manually move around files
on disk.
Anyhow, a work-around that you could do right now is to load up you
"old" materials library file as if it were a .fem file.  You can do
this, since the material properties database uses the same format for
the materials as in the .fem file.  Then, go to Properties|Materials
library.  You can then incorporate your materials into the "new"
library in a relatively painless way, by selecting your materials and
hitting the "Add selected material to library" button.
>  -
> controlling added points in non-linear materials is a little complicate.
> An optional log scale on H axis would help.
Yes, this is a good idea.  If one has a material whose definition
extends far into saturation, one can't see the detail at the left-hand
side of the curve.
>  -
> adding geometric inertia to block integral computation (possibly
> together
> with block volume) would be useful. (Best would be adding also material
> density to material properties and mass / inertia block integral
> computation)
> - adding possibility to display boundary labels.
Again, these are both good suggestions that I will "put on my list."
>  -
> what  about 2nd order elements?
This is something that I might do eventually, but this would require a
lot of changes to implement.  The Newton iteration that is used to
solve nonlinear magnetostatic problems is also a lot easier to
formulate in terms of 1st order triangles.

Thanks a lot for your suggestions.  I've been sort of planning a
stategy for additional things that I want to include in the 4.0
version, so your suggestions are well-timed.

Dave.
-- 
David Meeker
dmeeker@xxxxxxxx
http://femm.berlios.de/dmeeker