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A Numerical Model for Combustion of Bubbling Thermoplastic Materials in Microgravity



Kathryn M. Butler


A numerical model is demonstrated for the pyrolysis of a spherical thermoplastic sample in microgravity including effects of bubbles. The model combines nucleation, growth, and migration of individual bubbles in 3-D space with a finite element model that solves the 1-D radial equation for the temperature field. Energy calculations include surface losses due to radiation and convection, conductive heat transfer through the mixture of gaseous and condensed phase material, and the chemistry of gasification. Gases released by bursting bubbles determine the mass loss rate from the sample.
NIST Interagency/Internal Report (NISTIR) - 6894
Report Number


bubbles, combustion, finite element model, microgravity, numerical model, pyrolysis, thermoplastic materials


Butler, K. (2002), A Numerical Model for Combustion of Bubbling Thermoplastic Materials in Microgravity, NIST Interagency/Internal Report (NISTIR), National Institute of Standards and Technology, Gaithersburg, MD, [online], (Accessed April 17, 2024)
Created August 1, 2002, Updated June 2, 2021