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Femtime – mismatch for 2 different tlists
Posted 2015年2月12日 GMT-5 06:34 Mesh, Modeling Tools & Definitions, Parameters, Variables, & Functions, Studies & Solvers 0 Replies
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The system I solve is a coupled system (resistive heating) --> higher temperature --> higher current --> higher temperature and so on.
The system I look at has sharp temperature changes in a very short time (few ps). The overall simulation length however, is 100ns.
Therefore, I would like to split the calculation into a coarse tlist and a short one. I use COMSOL 3.5a with Matlab interface.
fem.sol=femtime(fem, ...
'init',fem0.sol, ...
'solcomp',{'T','sim_V1_p_i','V','Vconstra_g1_emdc'}, ...
'outcomp',{'T','sim_V1_p_i','V','Vconstra_g1_emdc'}, ...
'blocksize','auto', ...
'tlist',[colon((kappa+tau-1)*timeStep,timeStep/1E1,(kappa+tau)*timeStep)], ...
'tout','tlist', ...
'linsolver','spooles');
--------------------------------
coarse step
0ps:5ps:50ps
and for the fine one
0ps:0.1ps:10ps
The problem is that the solutions seems to kind of forget the old solution besides that it is fed back with fem0.sol to have a good starting value and I have no clue why.
If I use for the coarse step
0ps:5ps:50ps
and for the fine one
0ps:0.05ps:50ps
it works nicely meaning there the feedback fem0.sol works, however the step of 50ps is too coarse to accommodate the modified conductivity so I have to use 10ps and update the conductivity.
I am quite puzzled why COMSOL is struggling to use two different time steps.
If anyone could help me on that it would be great.
Many thanks and best regards,
Toby
Hello Tobias Bachmann
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