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Interpolated variable as initial value for time dependent eqn

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Hello,

I'm modeling a physical problem using stationary joule effect and time dependent PDE. I would like to use the solutions obtained from this two physics and plug it in order to use them as initial condition. I exported the variables, with the report fuction, I re-imported these data using interpolation, and I used them like the new initial codition in my 3D geometry. Unfortunately it seems that this initial condition make my time depedent solution to freeze at the inital value. I cannot understand the error? Any idea?

Thank you in advance, Stefano

2 Replies Last Post 25.02.2011, 04:03 GMT-5
Ivar KJELBERG COMSOL Multiphysics(r) fan, retired, former "Senior Expert" at CSEM SA (CH)

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Posted: 1 decade ago 22.02.2011, 13:21 GMT-5
Hi

I'm not sure I understand your sequence there. But can you not run the first simulation, add a store solution (manually) and then add your time dependent study with a starting Initial conditions from the stored solution ?

But I might have missed something when you relate to interpolated results

--
Good luck
Ivar
Hi I'm not sure I understand your sequence there. But can you not run the first simulation, add a store solution (manually) and then add your time dependent study with a starting Initial conditions from the stored solution ? But I might have missed something when you relate to interpolated results -- Good luck Ivar

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Posted: 1 decade ago 25.02.2011, 04:03 GMT-5
Thank you Ivar, I'm doing what you have suggested and it works well.

Apart from that what I would like to do is the following: I would like to solve the problem with a certain initial condition for the variable which the time dependent study solves for, and that I would like to use the solution I obtained as the inital condition for the time dependent study, in order to see if the problems reverses back or not.

Futhermore I added a parametric sweep that affect one parameter of the stationary solver and it works fine, but I think that every time the solvers compute the stationary and time dependent equation for one value of the parameter and that start again regalling the initial condition, I don't like that because I like the system to evolve from the values computed with the last parameter. Is it possible? Help and guides seems to me a little confusing.

-----

Scheme of the simulation:

Stationary -> variables u1 and u2
Time dependent -> recive in input u1 and u2 and solve for u3 with certain inital condition on u3

Thank you very much for your consideration, Stefano Larentis
Thank you Ivar, I'm doing what you have suggested and it works well. Apart from that what I would like to do is the following: I would like to solve the problem with a certain initial condition for the variable which the time dependent study solves for, and that I would like to use the solution I obtained as the inital condition for the time dependent study, in order to see if the problems reverses back or not. Futhermore I added a parametric sweep that affect one parameter of the stationary solver and it works fine, but I think that every time the solvers compute the stationary and time dependent equation for one value of the parameter and that start again regalling the initial condition, I don't like that because I like the system to evolve from the values computed with the last parameter. Is it possible? Help and guides seems to me a little confusing. ----- Scheme of the simulation: Stationary -> variables u1 and u2 Time dependent -> recive in input u1 and u2 and solve for u3 with certain inital condition on u3 Thank you very much for your consideration, Stefano Larentis

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