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how to increase the number of cycles in piecewise function.
Posted 08.04.2011, 01:13 GMT-4 Studies & Solvers, Structural Mechanics Version 4.0 9 Replies
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now i wanted to increase the cycles to 500 or even 1000 cycles......
typing in picesewise function for 500 or 1000 cycles i a long time job....
is there any other way to give the no of cycles in input...
D.Sanjay,
b'lore.
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but what do you expect to change between one cycle and 2, ...1000 ?
I would say rather calculate one cycle, and integrate manually whatever variable you have.
Now if this variable changing is influencing the calculations, you might manage to accumulate 100 cycles, then rerun with the new values, and accumulate again 100 cycles etc, this would cut down the calculation time, but I'm not sure it applies to your case ;)
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Good luck
Ivar
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i am finding the creep taking place in the solder (sandwich model) due to the influence of temperature.
i have attached an example of results required .
regards,
D.Sanjay
Attachments:
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then probably you need to run N cycles within COMSOL, if you have not other way to separate the effects, as I see the stress changes, but the temperature cycle is probably not affected
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Good luck
Ivar
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Hi
then probably you need to run N cycles within COMSOL, if you have not other way to separate the effects, as I see the stress changes, but the temperature cycle is probably not affected
--
Good luck
Ivar
thanks for the reply..
as i am new user to comsol... i wanted to know how to run N cycles.... in piecewise i could define only one cycle..
where can i define N cycles.. is there any tutorials for it..
d.sanjay
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no not really, make your load function periodical (in V4.1 you have an option in the analytical or piecewise functions somewhere ;) or use a modulo "t" and then run a long transient run
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Ivar
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with the help of piecewise function i have done single cycle. for running N cycles do i need any other software like MatLab or Comsol 4.0 itself can do it?
If Comsol 4.0 can do... can u help me in doing N cycles...
regards,
Sanjay.D
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if its a transient solver sequence, you need to make your cycle command periodic (repeating w.r.t. "t" time) you can use a modulo function, there are several threads thereon, try a search
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Good luck
Ivar
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i gave the piecewise function of one cycle i.e cycle finishing time is 900 s( 15min)
in the transient solver the time step is range(0,1,900)
if i increace the time in the solver for multiple cycles i.e (0,1,1800) i get solver error.
is there any way to cycle increase or do i need MATLAB or comsol can solve N cycles.?
regards,
SANJAY.D
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make sure that your time cycle is
1) really periodic with a function plot, and that it's derivable (no sharp steps, particularly at the transition)
2) then use a transient solver (for all periodic type responses) with the time step set to strict or intermediate (check the doc)
Or at least set a few extra time steps at the transition to get the solver to reconsider the slope of you signal, else it might skip over the repetition (and fail)
--
Good luck
Ivar