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how to input timestep size 'dt' in COMSOL 4.1
Posted Oct 11, 2011, 2:05 p.m. EDT Heat Transfer & Phase Change, Structural Mechanics 3 Replies
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Dear Friends,
I am new to this forum.
In my work, i need to give 'dt' as input...which is time step size...b
but i dont know how to input this in comsol...because its not recognizing dt...
please kindly help me...thanks for your time...
I am new to this forum.
In my work, i need to give 'dt' as input...which is time step size...b
but i dont know how to input this in comsol...because its not recognizing dt...
please kindly help me...thanks for your time...
3 Replies Last Post Oct 12, 2011, 1:20 a.m. EDT
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Posted:
1 decade ago
Hi
where do you want to input "dt" ? if it is for the sovler steps you use the "time stepping" field, but by default in "automatic" COMSOL will only take these as guess, and for output interpolation estimation. You need to turn on "strict" time stepping or "intermediate" and give your time steps (or range() limits explicitely) in the solver fields. Check the solver doc, and look carefully at the different solver node entries, all the way to the bottom of the tree ;)
if you need the dt for an integration, define the variable as an extra equation. See the COMSOL KB for examples
--
Good luck
Ivar
where do you want to input "dt" ? if it is for the sovler steps you use the "time stepping" field, but by default in "automatic" COMSOL will only take these as guess, and for output interpolation estimation. You need to turn on "strict" time stepping or "intermediate" and give your time steps (or range() limits explicitely) in the solver fields. Check the solver doc, and look carefully at the different solver node entries, all the way to the bottom of the tree ;)
if you need the dt for an integration, define the variable as an extra equation. See the COMSOL KB for examples
--
Good luck
Ivar
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Posted:
1 decade ago
Hallo Ivar,
thanks for your immediate and prompt reply.
instead of integrating the dt term, is there any way to input dt in the model...
i am very clear that its not the dt we define in the solver...
most of the time, comsol is taking automatic time stepping...
the dt which is used in the current timestep, i want to substitute in the model...
for eg:to model viscoplastic constitutive laws.....
with regards
ashok
thanks for your immediate and prompt reply.
instead of integrating the dt term, is there any way to input dt in the model...
i am very clear that its not the dt we define in the solver...
most of the time, comsol is taking automatic time stepping...
the dt which is used in the current timestep, i want to substitute in the model...
for eg:to model viscoplastic constitutive laws.....
with regards
ashok
Please login with a confirmed email address before reporting spam
Posted:
1 decade ago
Hi
are you sure it's not something like this you are looking for ?
www.comsol.eu/support/knowledgebase/1101/
or this one
www.comsol.eu/support/knowledgebase/1042/
--
Good luck
Ivar
are you sure it's not something like this you are looking for ?
www.comsol.eu/support/knowledgebase/1101/
or this one
www.comsol.eu/support/knowledgebase/1042/
--
Good luck
Ivar