Decontamination of Radionuclides from Concrete by Microwave Heating. II: Computations
This article is a reply.
VIEW THE ORIGINAL ARTICLEPublication: Journal of Engineering Mechanics
Volume 129, Issue 7
Abstract
Based on a mathematical model developed in the preceding Part I of this study, a numerical analysis of the process of decontamination of radionuclides from concrete by microwave heating is conducted. The aim is to determine the required microwave power and predict whether and when the contaminated surface layer of concrete spalls off. As customary, the finite element method is used for the stress and fracture analysis. However, as a departure from previous studies, the finite volume method is adopted to treat the heat and moisture transfer, in order to prevent spurious numerical oscillations that plagued the finite element response at moving sharp interface between the saturated and unsaturated concrete, and to deal accurately with the jumps in permeability and in sorption isotherm slope across the interface. The effects of wall thickness, reinforcing bars, microwave frequency, and power are studied numerically. As a byproduct of this analysis, the mechanism of spalling of rapidly heated concrete is clarified.
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Published In
Journal of Engineering Mechanics
Volume 129 • Issue 7 • July 2003
Pages: 785 - 792
Copyright
Copyright © 2003 American Society of Civil Engineers.
History
Received: Mar 12, 2002
Accepted: Oct 29, 2002
Published online: Jun 13, 2003
Published in print: Jul 2003
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