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Analytical Model of Pyrolysis for a Finite Thickness Sample on a Semi-Infinite Base (NISTIR 5904)



Kathryn M. Butler


To test the flammability of materials, a sample is placed on a substrate and exposed to a uniform heat flux. Measurements include sample mass and upper and lower surface temperatures as functions of time. Several analytical models have been developed in an attempt to fully understand the relationship between properties of the tested materials and test results. Most of these models have assumed a semi-infinite sample, although the finite thickness of the sample is known to have a significant effect on pyrolysis behavior. An analytical solution that includes finite sample thickness and the material properties of the base is introduced in this abstract.
NIST Interagency/Internal Report (NISTIR) - 5904
Report Number


fire research, fire science, thickness, pyrolysis, flammability tests, substrates, material properties


Butler, K. (1996), Analytical Model of Pyrolysis for a Finite Thickness Sample on a Semi-Infinite Base (NISTIR 5904), NIST Interagency/Internal Report (NISTIR), National Institute of Standards and Technology, Gaithersburg, MD, [online], (Accessed May 19, 2024)


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Created October 28, 1996, Updated November 10, 2018