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Defining initial condition
Posted Mar 20, 2012, 10:10 p.m. EDT Version 4.2 1 Reply
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Hi,
My geomtry is consisted of 2 boxes.
And, I am trying to define inital condition of one box by previous solution,
the other box by defining from initial values node.
But I found that the initial value of whole geomtry is defined by the previous solution.
Please help.
Thanks.
My geomtry is consisted of 2 boxes.
And, I am trying to define inital condition of one box by previous solution,
the other box by defining from initial values node.
But I found that the initial value of whole geomtry is defined by the previous solution.
Please help.
Thanks.
1 Reply Last Post Mar 21, 2012, 2:45 a.m. EDT
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Posted:
1 decade ago
Hi
indeed that is what I understand as the "default" behaviour. What you have not explained, is if you have 2 studies on the same pysics or 2 physics each with a separate physics.
I believe you need to define a model physics dependent variable, that is then solved by solution 1, and then in pyhsics 2 you define the initial condition with this variable
The only other trick I know about is if you mix a stationary and a time dependent series, then the variable "t" can be used a s "switch" for BC's, i.e. you define t=0 or t=-1[s] as a global parameter, solve the stationary solution by using boolean tests of the type (t<0) or t==0) and t>0) to switch the BC values at will, then when you launch the time setudy, COMSOl will overwrite the t value and make it grow, hence switch your BC to the time dependent case.
You can add another switch by using the stationary continuation sweep feature with a fixed parameer Param that you use too, see the example (it's 4.2a)
--
Good luck
Ivar
indeed that is what I understand as the "default" behaviour. What you have not explained, is if you have 2 studies on the same pysics or 2 physics each with a separate physics.
I believe you need to define a model physics dependent variable, that is then solved by solution 1, and then in pyhsics 2 you define the initial condition with this variable
The only other trick I know about is if you mix a stationary and a time dependent series, then the variable "t" can be used a s "switch" for BC's, i.e. you define t=0 or t=-1[s] as a global parameter, solve the stationary solution by using boolean tests of the type (t<0) or t==0) and t>0) to switch the BC values at will, then when you launch the time setudy, COMSOl will overwrite the t value and make it grow, hence switch your BC to the time dependent case.
You can add another switch by using the stationary continuation sweep feature with a fixed parameer Param that you use too, see the example (it's 4.2a)
--
Good luck
Ivar
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