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"Values of variables not solved for and linearization point " ?

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Hi!

In the solver manager, there is an option "Values of variables not solved for and linearization point",

I tried to understand this from the document, but it's really difficult to understand even the meaning of this sentence,
could someone explain more on this?

Especially I have a unconverge problem for a transient problem.
From the previous post, it's possible to change the options in the "Initial values" .

But will different options in "Values of variables not solved for and linearization point" affect convergence as well?
I tried some transient problem, seems the options here doesn't affect the result for a converged problem.

Thanks a lot.
BR,
Li


1 Reply Last Post Jun 18, 2010, 7:48 a.m. EDT
Ivar KJELBERG COMSOL Multiphysics(r) fan, retired, former "Senior Expert" at CSEM SA (CH)

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Posted: 1 decade ago Jun 18, 2010, 7:48 a.m. EDT
Hi

These settings are for defining the variables "not solved for", when you have multiple variables from multple physics and you use i.e. segregated solvers that only treats some, then what to do with the other values ?

You can either use your defined initial conditions, or used zero, or used last stored solution or just "restart" from previous calculated values

The linearisation point is typically for i.e. buckling analysis, when you first apply a linear (or non-linear) static analysis to "load" you case and then want to use this as the starting point for a modal analysis (which is always linear) but by linearising the case from this "loaded" starting point (again a multi-phyiscs solving in a segregated way)

Hope this heps
ivar
Hi These settings are for defining the variables "not solved for", when you have multiple variables from multple physics and you use i.e. segregated solvers that only treats some, then what to do with the other values ? You can either use your defined initial conditions, or used zero, or used last stored solution or just "restart" from previous calculated values The linearisation point is typically for i.e. buckling analysis, when you first apply a linear (or non-linear) static analysis to "load" you case and then want to use this as the starting point for a modal analysis (which is always linear) but by linearising the case from this "loaded" starting point (again a multi-phyiscs solving in a segregated way) Hope this heps ivar

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