International Scientific Journal

External Links


A transient one dimensional model has been presented to simulate degradation and gasification of polyethylene, in early stage of fire growth. In the present model effect of oxygen on degradation and rate of polymer gasification while the sample is subjected to an external radiative heat source is numerically investigated. This model includes different mechanism, which affect the degradation process, such as in depth thermal oxidative decomposition, in depth absorption of radiation, heat transfer, volatiles advection in solid phase and convective heat transfer on surface. Also effects of radiative parameters, due to formation of char layer such as surface reflectivity and absorptivity on thermal degradation of polyethylene are investigated. The results for 40 kW/m2 heat source are reported and yielded realistic results, comparing to the published experimental data. The results show that an increase in oxygen concentration leads to considerable increase in gasification rate and also leads to sharp increase of surface temperature. .
PAPER REVISED: 2006-03-30
PAPER ACCEPTED: 2006-05-01
CITATION EXPORT: view in browser or download as text file
  1. Esfahani, J. A., Sousa, A. C. M., Lopes, A. M. G., Numerical Modeling of Ignition by Radiation for a Cellulosic Material, in: Computational Modeling of Free and Moving Boundary Problems III, (Eds. L. C. Wrobel, B. Sarter, C. A. Brebbia), Computational Mechanics Publications, Southampton, UK, 1995, pp. 327-334
  2. Hirata, T., Kashiwagi, T., Brown, J. E., Thermal and Oxidative Degradation of Polymethyl Methacrylate: Weight Loss, Macromolecules, 18 (1985), 7, pp. 1410-1418
  3. Kashiwagi, T., Ohlemiller, T. J., A Study of Oxygen Effects on Nonflaming Transient Gasification of PMMA and PE during Thermal Degradation, Proceedings, 19th Symposium (Int.) on Combustion (1982), The Combustion Institute, Pittsburgh, Pa., USA, 1983, pp. 815-823
  4. Butler, K. M., A Mixed Layer Pyrolysis Model for Polypropylene, Proceedings (Ed. M. Curtat), 6th International Symposium, 2000, Intl. Assoc. for Fire Safety Science, Boston, MA, USA, pp. 313-324
  5. Butler, K. M., A Numerical Model for Combustion of Bubbling Thermoplastic Materials In Microgravity, Fire Research Division, Building and Fire Research Laboratory, National Institute of Standards and Technology, Gaithersburg, Md., USA, 2002
  6. Esfahani, J. A., Sousa, A. C. M., Ignition of Epoxy by a High Radiation Source, A Numerical Study, Int. J. Thermal Science, 38 (1999), 4, pp. 315-323
  7. Esfahani, J. A., Oxygen-Sensitive Thermal Degradation of PMMA: A Numerical Study, Combustion Science and Tech., 174 (2002), 10, pp. 183-198
  8. Esfahani, J. A., Kashani, A., A Numerical Model for Degradation and Combustion of Polymethyl Methacrylate (PMMA), Journal of Heat & Mass Transfer, 42 (2006), 6, pp. 569-576
  9. Eshafani, J. A., Ayani, M. B., Bakhtshirin, M., A Transient Two Dimensional Model of Thermal and Oxidative Degradation of PMMA, Iranian Journal of Science & Technology, Transaction B, Engineering, 29 (2005), No. B2, pp. 207-218
  10. Ohlemiller, T. J., Modeling of Smoldering Combustion Propagation, Progres in Energy Combustion Science, 11 (1985), 4, pp. 277-310
  11. Brown, J. E., Kashiwagi, T., Gas Phase Oxygen Effect on Chain Scission and Monomer Content in Bulk Poly (Methyl Methacrylate) Degraded by External Thermal Radiation, Polymer Degradation and Stability, 52 (1996), 1, pp. 1-10
  12. Kreith, F., Bohn, M. S., Principle of Heat Transfer, Proceedings, 5th ed., PWS Publishing Co., Minneapolis, Minn., USA, 1997
  13. Braaten, M. E., Shyy, W., Study of Pressure Correction Methods with Multigrid for Viscous Flow Calculation in Non Orthogonal Curvilinear Coordinates, Numerical Heat Transfer, Part A, 11 (1987), 4, pp. 417-442
  14. Pal, C., Macskasy, H., Plastics and Their Behavior in Fire, Elsevier Sciense Publishers, 1991
  15. Hallman, J., Welker, J. R., Sliepcevich, C. M., Polymer Surface Reflectance -Absorptance Characteristics, SPE Journal,14 (1974), 10, pp.717-723
  16. Lengelle, G., Thermal Degradation Kinetics and Surface Pyrolysis of Vinyl Polymer, AIAA Journal, 8 (1982), 11, pp. 1989-1996

© 2019 Society of Thermal Engineers of Serbia. Published by the Vinča Institute of Nuclear Sciences, Belgrade, Serbia. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution-NonCommercial-NoDerivs 4.0 International licence