Determination of Steel Emissivity for the Temperature Prediction of Structural Steel Members in Fire
Publication: Journal of Materials in Civil Engineering
Volume 25, Issue 2
Abstract
A numerical method, with which experimental results were processed, was adopted to measure the total emissivity of mild steel specimens at high temperatures. This method is derived from considering the transient thermal energy equilibrium between a steel specimen and its surrounding heating environment. As a first step to validate this method, the results obtained at a low temperature were compared with those using infrared thermographic techniques, and a good correlation of 87% was achieved. The numerical model was then extended to high temperatures to investigate the variation of emissivity of steel with temperatures. The convective heat transfer coefficient used in the numerical model was examined in great detail using results obtained from transient high temperature tests. The emissivity of steel obtained from this study shows that steel emissivity varies over a range of temperatures and the variation becomes more abrupt between 400 and 500°C. Formulation for the emissivity of steel at rising temperatures is recommended for steel design in fire.
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Information & Authors
Information
Published In
Journal of Materials in Civil Engineering
Volume 25 • Issue 2 • February 2013
Pages: 167 - 173
Copyright
© 2013 American Society of Civil Engineers.
History
Received: Apr 26, 2011
Accepted: Jun 5, 2012
Published online: Aug 29, 2012
Published in print: Feb 1, 2013
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