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Using consecutive solvers
Posted 09.03.2012, 18:47 GMT-5 Version 4.2, Version 4.2a 1 Reply
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Hi All
I am working on a time dependent and coupled multiphysics problem (drying of foodstuffs) in which most of the changes in the dependent variables take place primarily in the first few hours of drying. So in this part I have kept the maximum timestep a smaller value. But during later periods the dependent variables do not change much with time and so in order to save computation time I want to increase the maximum timestep (for the remaining times of drying). How should I go about doing this? Any suggestions in this regard is appreciated.
Many Thanks
Tushar
I am working on a time dependent and coupled multiphysics problem (drying of foodstuffs) in which most of the changes in the dependent variables take place primarily in the first few hours of drying. So in this part I have kept the maximum timestep a smaller value. But during later periods the dependent variables do not change much with time and so in order to save computation time I want to increase the maximum timestep (for the remaining times of drying). How should I go about doing this? Any suggestions in this regard is appreciated.
Many Thanks
Tushar
1 Reply Last Post 10.03.2012, 04:02 GMT-5
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Posted:
1 decade ago
Hi
first that is the default set up of comsol in "free" stepping mode. but you can also request an exponential stepping by the way you define your time sequence such as:
2^{range(-2,1,8)} => {1/4 1/2 1 2 4 8 16 32 64 128 256}
10^{range(0,1,3)} => {1 10 100 1000}
and you can use fractional steps too (you have some other too in the option of the "range definition pop up", I do not like that one as they have inverted the entries start step stop <=> start stop step, and I get it always wrong ;)
--
Good luck
Ivar
first that is the default set up of comsol in "free" stepping mode. but you can also request an exponential stepping by the way you define your time sequence such as:
2^{range(-2,1,8)} => {1/4 1/2 1 2 4 8 16 32 64 128 256}
10^{range(0,1,3)} => {1 10 100 1000}
and you can use fractional steps too (you have some other too in the option of the "range definition pop up", I do not like that one as they have inverted the entries start step stop <=> start stop step, and I get it always wrong ;)
--
Good luck
Ivar