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solving a two model problem

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Hello everybody,
i am new to comsol and i have a problem with my model.
It is a problem that uses General Heat Transfer getting the value of a heat source (Q) from a Perpendicular Induction Currents model.
The problem is that, when i ask it to solve the problem for both models then i get at time zero (transient analysis) a temperature that is non-zero (and quite big) and that makes no sense.
However, when i solve it for General Heat Transfer model only it runs correct.
any idea why is this happening?

1 Reply Last Post 20 janv. 2011, 09:07 UTC−5
Ivar KJELBERG COMSOL Multiphysics(r) fan, retired, former "Senior Expert" at CSEM SA (CH)

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Posted: 1 decade ago 20 janv. 2011, 09:07 UTC−5
Hi

this might be linked to an initial condition (but might also be something else ;) So I usually check my initial conditions by

v3.5a: Solve - Get initial conditions
v4.x right clicking the "solver sub-node": "Dependent vaiables" and select "compute to here"

Then I look at my initial conditions, and adjust if possible to get a shape that already looks like my result (with linear gradients etc. becausestarting all from "0" is often rather tough for the solver), furthermore this gives me indications when a BC is missing or that I have made singularity regions/points

--
Good luck
Ivar
Hi this might be linked to an initial condition (but might also be something else ;) So I usually check my initial conditions by v3.5a: Solve - Get initial conditions v4.x right clicking the "solver sub-node": "Dependent vaiables" and select "compute to here" Then I look at my initial conditions, and adjust if possible to get a shape that already looks like my result (with linear gradients etc. becausestarting all from "0" is often rather tough for the solver), furthermore this gives me indications when a BC is missing or that I have made singularity regions/points -- Good luck Ivar

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