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Modeling a Dielectric as a Real Capacitor
Posted Feb 15, 2013, 12:26 AM EST AC/DC & Electromagnetics, Modeling Tools, Parameters, Variables, & Functions Version 4.3a 9 Replies
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I am having trouble modeling something. I would like to look at the conduction/conductance/resistivity of a insulating/conductive composite. It could be thought to be like a polymer/insulating fiber system. Electrically, the polymer itself is referenced in literature to look like a capacitor and resistor in parallel. The capacitor illustrates the ideal dielectric capacitor that one might expect and the resistor illustrates the leakage that actually flows through the capacitor when placed in a potential. The illustration is on Tony Blythe's 2nd edition "Electrical Properties of Polymers" book on page 156. I've attached an image of the equivalent circuit I am talking about(not exactly the image from the book though).
I would like to know the DC electric conduction through the entire composite, so both in the low conductivity areas (the polymer/semi-insulator) and the in the high conductivity areas (which is a fiber/metal). Is there any way I can use components of both the Electostatics and Electric Currents Modules? I want it to take into account both the electrical conductivity and also the relative permittivity of the polymer. If so how can I do this? I've attached a 2D model of the geometry of what I'm talking about.
When I do this geometry in the EC interface, the electric field is not what is expected and when I do this geometry in the ES interface, I do get the correct e-field. I would like for the model to look like the ES does (which is what is expected) but actually have some current go through it.
Thanks in advance for any help you can shed for me!