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How to link studies ?? (a transient one using results from a stationary one)

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Hello comsol users

I am studying an open oven to heat copper wires, and I managed to model it in comsol with a stationnary solver. My original idea was to have a first study to put it in a steady state - done - (I assume stationnary solvers are made for that), and then in a second time make my wire pass trough the oven with a deformed mesh physic and watch if it is at the right temperature at the end of my tube (with a time-dependant study this time).

I wanted to have those 2 analysis running in a row (make the first one, keep the temperature distribution and put those results as initial conditions for the second one), but I don't know if it is possible with comsol and if it is, how am I suppose to do it.

Thank you in advance for your help!

4 Replies Last Post 06.07.2011, 02:42 GMT-4

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Posted: 1 decade ago 04.07.2011, 03:23 GMT-4
Sorry to insist but I really need it so I will try to explain a little clearer :

I run 2 stationnary studies to have my oven into running conditions (with 1 physics each to combine), and I need a third time-dependent study (with the 2 previous physics + a moving mesh one) to pass my object through the oven in running conditions (is to say with the conditions obtained after the 2 first step as initial conditions). And I don't know how to set those initial conditions.

Does anyone know how to do it??
Thx
Sorry to insist but I really need it so I will try to explain a little clearer : I run 2 stationnary studies to have my oven into running conditions (with 1 physics each to combine), and I need a third time-dependent study (with the 2 previous physics + a moving mesh one) to pass my object through the oven in running conditions (is to say with the conditions obtained after the 2 first step as initial conditions). And I don't know how to set those initial conditions. Does anyone know how to do it?? Thx

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Posted: 1 decade ago 04.07.2011, 03:31 GMT-4
I saw that one can just store the solution of a previous study step (I see how to do it) and then use that stored solution as initial conditions for a time dependant study step. But I can't find the option to do that, does anyone knows?
I saw that one can just store the solution of a previous study step (I see how to do it) and then use that stored solution as initial conditions for a time dependant study step. But I can't find the option to do that, does anyone knows?

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Posted: 1 decade ago 05.07.2011, 15:53 GMT-4
You have to create two steps and use the correct physics in each one. The first step is your stationary simulation. Your second is time dependent simulation. Then you show default solver and change your dependent variable for the second step. Use the stored solution from step 1.
Theoretically it is suppose to work but I'm having problem to solve it using for solid mechanic and emw simulation.

Good luck,

Gabriel
You have to create two steps and use the correct physics in each one. The first step is your stationary simulation. Your second is time dependent simulation. Then you show default solver and change your dependent variable for the second step. Use the stored solution from step 1. Theoretically it is suppose to work but I'm having problem to solve it using for solid mechanic and emw simulation. Good luck, Gabriel

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Posted: 1 decade ago 06.07.2011, 02:42 GMT-4
Hi gabriel, thanks for the reply.

I think this is what I did actually, but the issue is that I have one stat. step for fluid flow, an otherr stat.step for heat transfer DEPENDING on the first step (velocity of the fluid), and then I need a last step (time dependent) withe the two first physics + moving mesh . And I don't know how to solve this last step because how could comsol solve simultaneously 2 variables if they are weakly coupled??
I thought of segregated steps for the third solver but I don't know how they work :s....

So now I'm stuck again ^^
Hi gabriel, thanks for the reply. I think this is what I did actually, but the issue is that I have one stat. step for fluid flow, an otherr stat.step for heat transfer DEPENDING on the first step (velocity of the fluid), and then I need a last step (time dependent) withe the two first physics + moving mesh . And I don't know how to solve this last step because how could comsol solve simultaneously 2 variables if they are weakly coupled?? I thought of segregated steps for the third solver but I don't know how they work :s.... So now I'm stuck again ^^

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