Skip to main content
U.S. flag

An official website of the United States government

Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Secure .gov websites use HTTPS
A lock ( ) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.

Analysis of Effective Thermal Properties of Thermall Thick Materials

Published

Author(s)

Frederick W. Mowrer

Abstract

The standard methods used to derive effective thermal properties of thermally thick materials based on bench-scale radiant exposure tests are reviewed and analyzed. These methods are compared with numerical calculations for the same boundary conditions. These comparisons show that the standard analytical methods for predicting surface temperature histories are not accurate because they either ignore heat losses from the surface or do not adequately treat the highly nonlinear reradiative surface heat loss term. A method is presented for determining more accurate values for the thermal inertia based on effective values for this term published widely in the literature. It is found that actual thermal inertias tend to be lower by about a factor of 1.3 to 2.7 when compared with reported effective values for a wide range of conditions. This can have a significant effect on flame spread predictions for models that rely on accurate values for the thermal inertia.
Citation
Grant/Contract Reports (NISTGCR) - 03-855
Report Number
03-855

Keywords

thermal properties, ignition, thermial inertia

Citation

Mowrer, F. (2003), Analysis of Effective Thermal Properties of Thermall Thick Materials, Grant/Contract Reports (NISTGCR), National Institute of Standards and Technology, Gaithersburg, MD, [online], https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=916639 (Accessed May 18, 2024)

Issues

If you have any questions about this publication or are having problems accessing it, please contact reflib@nist.gov.

Created July 1, 2003, Updated August 7, 2014