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Cavity Effects and Hot Spot Formulation Inmicrowave Heated Ceramic Fibers

Published online by Cambridge University Press:  10 February 2011

G. A. Kriegsmann*
Affiliation:
New Jersey Institute of Technology, Department of Mathematics and the Center for Applied Mathematics and Statistics, Newark, NJ. 07102
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Abstract

Recently the heating of a thin ceramic cylinder in a single mode applicator was modeled and analyzed assuming a small Biot number and a known uniform electric field through out the sample. The resulting simplified mathematical equations explained the mechanism for the generation and growth of localized regions of high temperature. The results predicted that a hot-spot, once formed, will grow until it consumes the entire sample. Most experimental observations show that the hot-spot stabilizes and moves no further.

A new model is proposed which incorporates the effect of the cavity and the nlonuiniform character of the electric field along the axis of the sample. The resulting simplified mathematical equations indicate that these effects stabilize the growth of hot-spots.

Type
Research Article
Copyright
Copyright © Materials Research Society 1996

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