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Start time dependent study with initial conditions from a stationary converged solution

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Hello World.

I would like to solve a non-isothermal single phase flow with natural convection.
As I have some problems at the beginning of the solution process I thought about a method to solve such a problem by solving a stationary problem until convergence to create an initial condition for a time dependent study.

Any ideas how I can achieve this?

Thanks in advance!
Sebastian


1 Reply Last Post 18 nov. 2011, 04:00 UTC−5
Ivar KJELBERG COMSOL Multiphysics(r) fan, retired, former "Senior Expert" at CSEM SA (CH)

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Posted: 1 decade ago 18 nov. 2011, 04:00 UTC−5
Hi

in V4 you add a stationary study-solving node before your time dependent node, and COMSOL will link them and use the stationary case as initial conditions (if you have tweaked your solver sequence, you should regenerate a new "default" one to get the solver sequence correctly updated by COMSOL.

Furthmore, if you use the variable "t" in some of your BC's or elsewhere, it will not be defined for the stationary solving case. My workaround is to define a Global Parameter t = 0[s] and set it to the first, or any convenient time step value

--
Good luck
Ivar
Hi in V4 you add a stationary study-solving node before your time dependent node, and COMSOL will link them and use the stationary case as initial conditions (if you have tweaked your solver sequence, you should regenerate a new "default" one to get the solver sequence correctly updated by COMSOL. Furthmore, if you use the variable "t" in some of your BC's or elsewhere, it will not be defined for the stationary solving case. My workaround is to define a Global Parameter t = 0[s] and set it to the first, or any convenient time step value -- Good luck Ivar

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