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RF Module. Microwave Heating
Posted 09.08.2010, 09:11 GMT-4 Version 4.1 2 Replies
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Hello Comsol Multiphysics Specialists!
My name is Gadjiko I am using actively Comsol Multiphysics, version 3.5a and loving it.
I am modeling the microwave heating for different materials with different physical properties. As we all know that in the problem solution, only the wave equation for the electric field vector E is solved and the permeability of the potato is considered to be 1. Now my question is how can I model the heating process with the consideration of both wave equation for electric field vector and magnetic field vector at the same time and with the introduction of complex values for the relative permittiivity and relative permeability of the material?
If anyone knows, including the comsol Support desk, how to write this model and make it work please help me out.
Thank you in advance for your support.
My name is Gadjiko I am using actively Comsol Multiphysics, version 3.5a and loving it.
I am modeling the microwave heating for different materials with different physical properties. As we all know that in the problem solution, only the wave equation for the electric field vector E is solved and the permeability of the potato is considered to be 1. Now my question is how can I model the heating process with the consideration of both wave equation for electric field vector and magnetic field vector at the same time and with the introduction of complex values for the relative permittiivity and relative permeability of the material?
If anyone knows, including the comsol Support desk, how to write this model and make it work please help me out.
Thank you in advance for your support.
2 Replies Last Post 30.06.2011, 13:38 GMT-4
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Posted:
1 decade ago
Hi,
The time harmonic electromagnetic waves formulation is deduced from both Maxwell-Ampère's law and Faraday's induction law so even though it solves for the complex phasor field E, magnetic effects are also accounted for.
To include magnetic loss, just specify a complex-valued relative permeability with:
Im{mur}<0
In versions 3.5a as in version 4, there is a ready-made postprocessing variable for "magnetic hysteresis loss" that you use to postprocess the magnetic losses.
NB. In physics and optics, it is common to use a different time harmonic sign convention, i.e.
E(r,t) = Re{exp(-i*w*t)*E(r)}
rather than the one used in COMSOL (common in engineering).
E(r,t) = Re{exp(+i*w*t)*E(r)}
The former leads to loss being represented by:
Im{mur}>0
so be cautios when taking complex-valued material data from the literature - it may have to be conjugated before being input to COMSOL. In COMSOL a material with positive imaginary part to mur or epsilonr yields a "gain".
I hope this helps,
Magnus Olsson
COMSOL
The time harmonic electromagnetic waves formulation is deduced from both Maxwell-Ampère's law and Faraday's induction law so even though it solves for the complex phasor field E, magnetic effects are also accounted for.
To include magnetic loss, just specify a complex-valued relative permeability with:
Im{mur}<0
In versions 3.5a as in version 4, there is a ready-made postprocessing variable for "magnetic hysteresis loss" that you use to postprocess the magnetic losses.
NB. In physics and optics, it is common to use a different time harmonic sign convention, i.e.
E(r,t) = Re{exp(-i*w*t)*E(r)}
rather than the one used in COMSOL (common in engineering).
E(r,t) = Re{exp(+i*w*t)*E(r)}
The former leads to loss being represented by:
Im{mur}>0
so be cautios when taking complex-valued material data from the literature - it may have to be conjugated before being input to COMSOL. In COMSOL a material with positive imaginary part to mur or epsilonr yields a "gain".
I hope this helps,
Magnus Olsson
COMSOL
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Posted:
1 decade ago
Can I couple laminar flow model to microwave heating in 4.1? if yes how?
or will I have to couple Electromagnetics with the non isothermal flow?
or will I have to couple Electromagnetics with the non isothermal flow?