Modeling the UL-94 vertical burning test is of practical importance in industries which, however, has not been addressed sufficiently. In this article, a 3D convective heat transfer model was developed to simulate ignition times for the UL-94 test. An experimental procedure was proposed to measure ignition times of two polymers under the UL-94 test condition. Comparisons between experimental and simulated results of ignition times showed that edge effects were significant in the ignition process of the UL-94 test and the convective heat transfer ignition model considering edge effects gave ignition times close to experimental results. Sensitivity analyses showed that the ignition time increased linearly with decreasing initial temperature and increasing density, heat capacity and emissivity, but nonlinearly with decreasing flame temperature and convective heat transfer coefficient and increasing thickness, thermal conductivity, and ignition temperature of the specimen.
Ul-94 (1996). Test for Flammability of Plastic Materials for Parts in Devices and Appliances.
2.
Drysdale, D. ( 1999). An Introduction to Fire Dynamics, 2nd edn, John Wiley & Sons Ltd, England.
3.
Atreya, A. ( 1998). Ignition of Fires, Philosophical Transactions of the Royal Society of London A, 356: 2787-2813.
4.
Shen, D.K., Fang, M.X. and Chow, W.K. ( 2006). A Review on Ignition of Cellulose Materials under External Heat Flux, International Journal of Engineering Performance-based Fire Codes, l8(1): 28-42.
5.
Jiang, Y. ( 2006). Decomposition, Ignition and Flame Spread on Furnishing Materials, Center for Enviroment Safety and Risk Engineering, Victoria University, Australia.
6.
Lyon, R.E. and Quintiere, J.G. ( 2007). Criteria for Piloted Ignition of Combustible Solids , Combustion and Flame, 151: 551-559.
7.
Bucsi, A. and Rychly, J. ( 1999). Ignitability of Polymers Related to Polymer Properties and Different Steady States of Combustion: Theoretical Approach, Journal of Thermal Analysis and Calorimetry, 55: 727-739.
8.
Delichatsios, M.A. and Delichatsios, M.M. ( 1997). Critical Mass Pyrolysis Rates for Extinction of Fires over Solid Materials, Fire Safety Science, In: Proceedings of the Fifth International Symposium, March 3-7, Melbourne, Australia, pp. 153-164.
9.
Lyon, R.E. and Janssens, M.L. ( 2005). Polymer Flammability, Final Report DOT/FAA/AR-05/14 .
10.
Nelson, M.I. , Brindlev, J. and Mcintosh, A. (1996). Polymer Ignition, Mathematical and Computer Modelling , 24(8): 39-46.
11.
Staggs, J.E.J. and Nelson, M.I. (2001). A Critical Mass Flux Model for the Flammability of Thermoplastics, Combustion Theory and Modelling, 5: 399-427.
12.
Staggs, J.E.J. (2001). Ignition of Char-forming Polymers at a Critical Mass Flux, Polymer Degradation and Stability, 74: 433-439.
13.
Tran, H.C. and White, R.H. ( 1992). Burning Rate of Solid Wood Measured in a Heat Release Rate Calorimeter, Fire and Materials, 16: 197-206.
14.
Tran, H.C., Cohen, J.D. and Chase, R.A. ( 1992). Modeling Ignition of Structures in Wildland/urban Interface Fires, In: Proceedings of the 1st International Fire and Materials Conference, September 24-25, London, UK, pp. 253-262.
15.
Fernandez-Pello, A. and Williams, F.A. (1977). A Theory of Laminar Flame Spread over Flat Surfaces of Solid Combustions, Combustion and Flame, 28: 251-277.
16.
Chander, S. and Ray, A. ( 2005). Flame Impingement Heat Transfer: A Review, Energy Conservation and Management , 46: 2803-2837.
17.
ASTM D 5207 (2003). Standard Practice for Confirmation of 20-mm (50-W) and 125-mm (500-W) Test Flames for Small-Scale Burning Tests on Plastic Materials.
18.
ASTM D 5025 (2005). Standard Specification for Laboratory Burner Used for Small-Scale Burning Tests on Plastic Materials.
19.
Baukal, C.E. ( 2000). Heat Transfer in Industrial Combustion, CRC Press LLC, Florida.
20.
Hsieh, W.D. , Hou, S.S. and Lin , T.H. (2005). Methane Flames in a Jet Impinging onto a Wall, In: Proceedings of the Combustion Institute, Vol. 30, pp. 267-275.
21.
Heberle, N.H.Smith, G.P., Jeffries, J.B., Crosley, D.R. and Dibble, R.W. ( 2000). Simultaneous Laser-induced Fluorescence and Rayleigh Scattering Measurements of Structure in Partially Premixed Flames, Appl. Phys. B, 71: 733-740.
22.
Weng, W.G. and Hasemi, Y. ( 2006). Heat Transfer to an Unconfined Ceiling from an Impinging Buoyant Diffusion Flame, Heat Mass Transfer, 42: 652-659.
23.
Koohyar, A.N. , Welker, J.R. and Sliepcevich , C.M. (1968 ). The Irradiation and Ignition of Wood by Flame, Fire Technology , 4(4): 284-291.
24.
Quintiere, J.G. and Cleary, T.G. (1994). Heat Flux from Flames to Vertical Surfaces, Fire Technology, 30(2): 209-231.
25.
Liakos, H.H. , Karamida, F.P., Founti, M.A. and Markatos, N.C. (2002). Heat and Mass Transfer Study of Impinging Turbulent Premixed Flames , Heat and Mass Transfer, 38: 425-432.
26.
Dong, L.L., Leung, C.W. and Cheung, C.S. ( 2002). Heat Transfer Characteristics of Premixed Butane/Air Flame Jet Impinging on an Inclined Flat Surface, Heat and Mass Transfer, 39: 19-26.
27.
Kalchevski, S.K. and Lebedev, V.I. (1981). Heat-transfer Characteristics of a Jet Flame Impinging on a Heat-sensing Surface, Journal of Engineering Physics and Thermophysics, 40(1): 6-8.
28.
Atreya, A. , Carpentier, C. and Harkleroad, M. ( 1986). Effect of Sample Orientation on Piloted Ignition and Flame Spread, Fire Safety Science, In: Proceedings of the First International Symposium, pp. 97-109.
29.
Lyon, R.E. ( 1999). Solid-state Thermochemistry of Flaming Combustion, Final Report DOT/FAA/AR-99156.
30.
Remie, M.J. , Cremers, M.F.G., Schreel, K.R.A.M. and de Goey , L.P.H. ( 2007). Analysis of the Heat Transfer of an Impinging Laminar Flame Jet, International Journal of Heat and Mass Transfer , 50: 2816-2827.
Thomson, H.E. and Drysdale , D.D. (1987). Flammability of Plastics I: Ignition Temperatures, Fire and Materials, 11: 163-172.
33.
Atreya, A. and Abu-zaid, M. ( 1991). Effect of Environmental Variables on Piloted Ignition, Fire Safety Science, In: Proceedings of the Third International Symposium, London, pp. 177-186.
34.
C.A. Harper ( 2004). Handbook of Building Materials for Fire Protection, Chapter 3, Plastics and Rubber, pp. 3.1-3.51, McGraw-Hill , New York.
35.
ISO 6940 (2003). Textile Fabrics - Burning Behaviour - Determination of Ease of Ignition of Vertically Oriented Specimens.
