The Combustion of Polymeric Materials

Polymeric materials are widely used in buildings and construction applications and there is considerable interest in reducing their fire hazard. The combustion of solid polymers is a complicated process involving physical phenomena that are only partially understood. Simple mathematical models are being developed in order to gain an insight into the combustion characteristics of such materials.

The areas of interest described above are for test-methods which are `spatially uniform' in the sense that the source term is applied uniformally across one side of the test-sample. Test methods involving non-uniform source terms are also common, e.g. tests employing wooden cribs as the ignition source. Models for such experiments involve non-local reaction-diffusion equations. The mathematical behaviour of such systems has been little investigated. One of my long-term research goals is to investigate such models.

Highlights of research in polymer combustion

  1. The use critical mass flux models to systematically investigate the combustion characteristics of polymers and polymer-additive systems.
  2. Offered an explanation of ``anomalous'' experimental data on the time-to-ignition for polymer systems retarded with inert/heat-sink additives.
  3. The development and analysis of a dynamical systems model for polymer combustion in the cone calorimeter. I showed that bifurcation theory provides the tools to establish generic types of burning behaviour and to understand the transitions between them, e.g. the change between sustaining and non-sustaining combustion. In turn this offers a basis for a systematic investigation into which types of additive optimise the retardancy of different classes of polymer.
  4. The limiting oxygen index test
    1. Using a dynamical systems framework I showed how the limiting oxygen index can be identified as an appropriate bifurcation in a model that had previously been investigated only by direct integration. Showed how this critical value related to different types of burning behaviour: marginally-stable materials, self-extinguishing polymers and intrinsically non-flammable. (abstract)
    2. The previous model was extended to include two common fire retardant mechanisms: non-competitive char-formation and dilution by an inert filler. The types of material that are best retarded by each mechanism were identified. (abstract)

My collaborators in modelling polymer combustion

Dr. E. Balakrishnan. 1997-1999
Professor J. Brindley. 1990-2002
Dr. A.C. McIntosh. 1994-2002
Dr. G.N. Mercer. 1998-2001
Dr. H. Sidhu. 1997-2002
Dr. J.E.J. Staggs. 1996-2001
Professor G.C. Wake. 1997-1999
Dr. R.O. Weber. 1998-2001

Publications on Polymer Combustion

    Refereed papers

  1. M.I. Nelson, J. Brindley, and A.C. McIntosh. A Mathematical Model of Ignition in the Cone Calorimeter. Combustion Science and Technology, 104:35-54, 1995.
  2. M.I. Nelson and J. Brindley. Modelling Char-Formation in Isothermal and Non-Isothermal Thermogravimetric Experiments. Thermochimica Acta, 258:175-188, July 1995.
  3. M.I. Nelson, J. Brindley, and A.C. McIntosh. The Dependence of Critical Heat Flux on Fuel and Additive Properties: A Critical Mass Flux Model. Fire Safety Journal, 24(2):107-130, 1995.
  4. M.I. Nelson, J. Brindley, and A.C. McIntosh. Ignition Properties of Thermally Thin Materials in the Cone Calorimeter: A Critical Mass Flux Model. Combustion Science and Technology, 113-114:221-241, 1996.
  5. M.I. Nelson, J. Brindley, and A.C. McIntosh. Polymer Ignition. Mathematical and Computer Modelling, 24(8):39-46, October 1996.
  6. M.I. Nelson, J. Brindley, and A.C. McIntosh. Ignition Properties of Thermally Thin Thermoplastics - The Effectiveness of Inert Additives in Reducing Flammability. Polymer Degradation and Stability, 54(2-3):255-267, 1996.
  7. M.I. Nelson, J. Brindley, and A.C. McIntosh. The Effect of Heat Sink Additives on the Ignition and Heat Release Properties of Thermally Thin Thermoplastics. Fire Safety Journal, 28(1): 67-94, February 1997.
  8. M.I. Nelson. Ignition Mechanisms of Thermally Thin Thermoplastics in the Cone Calorimeter. Proceedings of the Royal Society of London A, 454(1971):789-814, March 1998.
  9. E. Balakrishnan, M.I. Nelson, and G.C. Wake. Radiative Ignition of Combustible Materials I. Polymeric Materials Undergoing Non-Flaming Thermal Degradation - The Critical Storage Problem.
  10. Mathematical and Computer Modelling, 30(11-12):177-195, December 1999.
  11. M.I. Nelson and J. Brindley. Polymer Combustion: Effects of Flame Emissivity. Philosophical Transactions of the Royal Society of London Series A, 357:3655-3673, December 1999.
  12. M.I. Nelson. A dynamical systems model of the limiting oxygen index test. II Retardancy due to char-formation and addition of inert fillers. Combustion Theory and Modelling, 5(1): 59-83, March 2001.
  13. M.I. Nelson, H.S. Sidhu, R.O. Weber, and G.N. Mercer. A dynamical systems model of the limiting oxygen index test. ANZIAM Journal, 43(1): 105-117, 2001.
  14. J.E.J. Staggs and M.I. Nelson. A critical mass flux model for the flammability of thermoplastics. Combustion Theory and Modelling, 5(3), 399-427, September 2001.
  15. M.I. Nelson. Thermally thin materials with enhanced fire-resistant properties: A dynamical systems model. Combustion Science and Technology, 167: 82-112, 2001.
  16. M.I. Nelson, J. Brindley and A.C. McIntosh. Ignition properties of thermally thin plastics: The effectiveness of non-competitive char formation in reducing flammability. Journal of Applied Mathematics and Decision Sciences, 6(3): 155-181, 2002.
  17. Letters to the editor

  18. M.I. Nelson, J. Brindley, and A.C. McIntosh. Letter to the Editor: Response. Fire Safety Journal, 25(4): 357-360, November 1996.
  19. Refereed conference proceedings

  20. M.I. Nelson. A Dynamical Systems Model of Autoignition in the Cone Calorimeter. In Fire Safety Science: Proceedings of the Fifth International Symposium, pages 547-558. International Association for Fire Safety Science, 1997. ISBN 4-9900625-5-5.
  21. N. Waterhouse, H.S. Sidhu and M.I. Nelson. Polymer combustion: The critical mass flux model. In M. Pemberton, I. Turner, and P. Jacobs, editors, EMAC 2002 Proceedings, pages 231--236. The Institution of Engineers, Australia, 2002. ISSN 1447-378X.
  22. Unrefereed conference proceedings

  23. M.I. Nelson. The Autoignition of Thermoplastics in the Cone Calorimeter: A Dynamical Systems Model. In Proceedings of the 16th International Colloquium on the Dynamics of Explosions and Reactive Systems, pages 494-497. Wydawnictwo,, Akapit'' (Kraków, Poland), 1997. ISBN 83-7108-028-X.

Short articles on polymer combustion

I've written a series of short articles. Each of these provide a short overview of a particular topic that I've investigated in my research. Several of them deal with polymer combustion.

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Page Created: 18th April 2002.
Last Updated: 13th February 2004.