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Growth and Stabilization of Hot Spots in Microwave Heated Ceramic Fibers

Published online by Cambridge University Press:  15 February 2011

Gregory A. Kriegsmann
Gregory A. Kriegsmann*
Affiliation:
Department of Mathematics, Center for Applied Mathematics and Statistics, New Jersey Institute of Technology, University Heights, 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. Although this phenomenon is seen in some experiments, others show that the hot-spot stabilizes and moves no further.

A new model is proposed which incorporates the dependence of the thermal conductivity and the effective heat transfer coefficient upon temperature, and the nonuniformity of the electric field along the fiber axis. The resulting simplified mathematical equations indicate that these effects may stabilize the growth of hot-spots.

Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 347: Symposium O – Microwave Processing of Materials IV , 1994 , 473
Copyright
Copyright © Materials Research Society 1994

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References

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