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Help with heat transfer module, the definition of bulk heat source!

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Hi there, I am working on a thermal decomposition study. The problem is that when the compund is heated, it will generate heat by decomposing, therefore I need to define a bulk heat source. The generation of heat (which is reaction rate) follows Arrhenius law, which is (1-epsilon)Zexp(-E/R/T) (Z, E, R are constants, T is temperature), where epsilon is mass fraction of the compound. However epsilon itself needs to be calculated through integration of reaction rate. I don't know how to realize that in COMSOL. It seems in other softwares like FLUENT or Abaqus it need user subroutine to fulfil the task. Anyone has any idea about how to do that in COMSOL? Thanks a lot.


1 Reply Last Post Sep 29, 2017, 5:22 a.m. EDT
Ivar KJELBERG COMSOL Multiphysics(r) fan, retired, former "Senior Expert" at CSEM SA (CH)

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Posted: 7 years ago Sep 29, 2017, 5:22 a.m. EDT

Hi

You need to add an ODE or a new dependent variable to your model to take this additional integration into account. Check the Blog, and the Application library for examples.

Sicenrely Ivar

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Have fun COMSOLing,
Sincerely,
Ivar
Hi You need to add an ODE or a new dependent variable to your model to take this additional integration into account. Check the Blog, and the Application library for examples. Sicenrely Ivar

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