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microwave heating

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Hello,

In microwave heating, material permittivity in different temperature is different.
But in comsol process, when we heating material, temperature is rise, material permittivity will be different, isn't it?
So In microwave heating simulation material permittivity is changed or not?

Thank you very much!

2 Replies Last Post 28 mai 2012, 20:20 UTC−4
Ivar KJELBERG COMSOL Multiphysics(r) fan, retired, former "Senior Expert" at CSEM SA (CH)

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Posted: 1 decade ago 28 mai 2012, 03:44 UTC−4
Hi

that depends on how you define your dependent varaibles, if your material permittivity is explicitely dependent on T and you have a varying T solved during the solver process then COMSOL will take the permittivity change into account, you will see COMSOl using an iterative non-linear solver to loop around, you can also see this in the segregated solver steps, which variable comes first then second etc.

Now v4.0 was somehwat limited in its automatic set up of all solver conditions and you might need to adapt the solver ndes by hand, in certain cases. It's highly improved in the later versions

--
Good luck
Ivar
Hi that depends on how you define your dependent varaibles, if your material permittivity is explicitely dependent on T and you have a varying T solved during the solver process then COMSOL will take the permittivity change into account, you will see COMSOl using an iterative non-linear solver to loop around, you can also see this in the segregated solver steps, which variable comes first then second etc. Now v4.0 was somehwat limited in its automatic set up of all solver conditions and you might need to adapt the solver ndes by hand, in certain cases. It's highly improved in the later versions -- Good luck Ivar

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Posted: 1 decade ago 28 mai 2012, 20:20 UTC−4
Thank you very much

Thank you very much

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