Abstract
Most of previous work focused on the one-sided upward flame spread over inclined surfaces. However, few investigations have systematically addressed the dependence of spread rate on the inclination angle for two-sided upward flame spreading. The present paper investigates the two-sided upward flame behaviors over inclined surfaces by performing experiments using 0.255 mm thick, 100 cm tall and 5 cm wide cotton sample sheets with various inclination angles varying 0° to 90° from the horizontal. The pyrolysis spread rate, pyrolysis length, preheating length, ignition time, flame tilt angle and standoff distance are obtained and analyzed. The corresponding results are as follows: As the inclination angle increases, the pyrolysis spread rate, pyrolysis length and preheating length increase, but the ignition time decreases. One transition zone is observed around 10° to 15° for flame spread rate, pyrolysis length and preheating length, which is an external manifestation of the change of flame spread from steady state to acceleration. Two parameters of tilt angle and standoff distance are used to qualitatively modify the heat flux profiles ahead of the flame front, which control the flame spread rate. Generally, the tilt angle and standoff distance of upper flame decrease as a function of inclination angle. On the contrary, the standoff distance shows an opposite trend with inclination angle. The combined effects of radiation and convection of upper and lower flames result in a sharp increase in net heat flux, and correspondingly a transition zone occurs around 10° to 15°. The results of this study have implications concerning designs for fire safety and may help advance understanding of two-sided flame spread over inclined surfaces.
Similar content being viewed by others
References
Ito A, Kashiwagi T (1988) Characterization of flame spread over PMMA using holographic interferometry sample orientation effects ☆. Combust Flame 71(2):189–204
Drysdale DD, Macmillan AJR (1992) Flame spread on inclined surfaces. Fire Saf J 18(3):245–254
Quintiere. JG (2001) The effects of angular orientation on flame spread over thin materials. Fire Saf J 36:291–312
Pizzo Y, Consalvi JL, Porterie B (2009) A transient pyrolysis model based on the B-number for gravity-assisted flame spread over thick PMMA slabs. Combust Flame 156(9):1856–1859. https://doi.org/10.1016/j.combustflame.2009.06.007
Zhang Y, Ji J, Li J, Sun J, Wang Q, Huang X (2012) Effects of altitude and sample width on the characteristics of horizontal flame spread over wood sheets. Fire Saf J 51:120–125. https://doi.org/10.1016/j.firesaf.2012.02.006
Gollner MJ, Huang X, Cobian J, Rangwala AS, Williams FA (2013) Experimental study of upward flame spread of an inclined fuel surface. Proc Combust Inst 34:2531–2538. https://doi.org/10.1016/j.proci.2012.06.063
Huang X, Gollner M (2014) Correlations for evaluation of flame spread over an inclined fuel surface. Fire Saf Sci 11:222–233. https://doi.org/10.3801/iafss.fss.11-222
Ohtani H, Ohta K, Uehara Y (1991) Effect of orientation on burning rate of solid combustible. Fire Mater 15(4):191–193
Markstein GH, de Ris J (1973) Upward fire spread over textiles. Symp Combust 14(1):1085–1097
Avinash G, Kumar A, Raghavan V (2016) Experimental analysis of diffusion flame spread along thin parallel solid fuel surfaces in a natural convective environment. Combust Flame 165:321–333. https://doi.org/10.1016/j.combustflame.2015.12.015
Wu Y, Xing HJ, Atkinson G (2000) Interaction of fire plume with inclined surface. Fire Saf J 35(4):391–403
Hu L, Zhang Y, Yoshioka K, Izumo H, Fujita O (2015) Flame spread over electric wire with high thermal conductivity metal core at different inclinations. Proc Combust Inst 35(3):2607–2614
Hu L, Lu Y, Yoshioka K, Zhang Y, Fernandez-Pello C, Chung SH, Fujita O (2017) Limiting oxygen concentration for extinction of upward spreading flames over inclined thin polyethylene-insulated NiCr electrical wires with opposed-flow under normal- and micro-gravity. Proc Combust Inst 36(2):3045–3053. https://doi.org/10.1016/j.proci.2016.09.021
Comas B, Pujol T (2013) Flame front speed and onset of instability in the burning of inclined thin solid fuel samples. Phys Rev E. https://doi.org/10.1103/physreve.88.063019
Tsai KC, Drysdale D (2002) Flame height correlation and upward flame spread modelling. Fire Mater 26(6):279–287. https://doi.org/10.1002/fam.809
Cheng Q, Ishida H, Saito K (1994) Upward flame spread along PMMA vertical corner walls Part II: mechanism of “M” shape pyrolysis front. Combust Flame 99(2):331–338
Urbas J, Parker WJ, Luebbers GE (2004) Surface temperature measurements on burning materials using an infrared pyrometer: Accounting for emissivity and reflection of external radiation. Fire Mater 28(1):33–53. https://doi.org/10.1002/fam.844
Miller CH (2014) Upward flame spread over discrete fuels. In: U.S. national combustion meeting, pp 36–45
Zhu H, Zhu G, Gao Y, Zhao G (2017) Experimental studies on the effects of spacing on upward flame spread over thin PMMA. Fire Technol 53(2):673–693
Arakawa A, Saito K, Gruver WA (1993) Automated infrared imaging temperature measurement with application to upward flame spread studies. Part I. Combust Flame 92(3):222–230
Liang CJ, Cheng XD, Yang H, Zhang HP, Yuen KK (2016) Experimental study of vertically upward flame spread over polymethyl methacrylate slabs at different altitudes. Fire Mater 40(3):472–481. https://doi.org/10.1002/fam.2304
Ying SJ (1971) Flame propagation of burning solid material with moisture. Fire Technol 7(3):243–250
Miller B, Martin JR, Goswami BC, Meiser CH (1975) The effects of moisture on the flammability characteristics of textile materials. Text Res J 45(4):328–337
Safronava N, Lyon RE, Crowley S, Stoliarov SI (2014) Effect of moisture on ignition time of polymers. Fire Technol 51(5):1093–1112. https://doi.org/10.1007/s10694-014-0434-1
Zhang Y, Ji J, Wang Q, Huang X, Wang Q, Sun J (2012) Prediction of the critical condition for flame acceleration over wood surface with different sample orientations. Combust Flame 159(9):2999–3002. https://doi.org/10.1016/j.combustflame.2012.04.007
Zhang Y, Sun JH, Huang XJ, Chen XF (2013) Heat transfer mechanisms in horizontal flame spread over wood and extruded polystyrene surfaces. Int J Heat Mass Transf 61:28–34. https://doi.org/10.1016/j.ijheatmasstransfer.2013.01.069
Huang X, Chen G, Liu W, Zhang Y, Sun J (2017) Thermal analysis of vertical upward flame spread and dripping behaviors of polystyrene foams at different altitudes. J Macromol Sci B 56(8):517–531. https://doi.org/10.1080/00222348.2017.1330133
Ohlemiller T, Shields J (1993) One and two sided burning of thermally thin materials. Fire Mater 17:103–110
Rakesh Ranga HR, Korobeinichev OP, Harish A, Raghavan V, Kumar A, Gerasimov IE, Gonchikzhapov MB, Tereshchenko AG, Trubachev SA, Shmakov AG (2018) Investigation of the structure and spread rate of flames over PMMA slabs. Appl Therm Eng 130:477–491. https://doi.org/10.1016/j.applthermaleng.2017.11.041
Hurley MJ, Gottuk DT, JR Hall Jr, Harada K, Kuligowski ED, Puchovsky M, Torero JL, JM Watts Jr, Wieczorek CJ (2016) SFPE handbook of fire protection engineering. Springer, New York
An W, Huang X, Wang Q, Zhang Y, Sun J, Liew K, Wang H, Xiao H (2013) Effects of sample width and inclined angle on flame spread across expanded polystyrene surface in plateau and plain environments. J Thermoplast Compos Mater 28(1):111–127. https://doi.org/10.1177/0892705713486132
Zhang Y, Huang X, Wang Q, Ji J, Sun J, Yin Y (2011) Experimental study on the characteristics of horizontal flame spread over XPS surface on plateau. J Hazard Mater 189(1–2): 34–39. https://doi.org/10.1016/j.jhazmat.2011.01.101
Acknowledgments
This work was supported by National Key Research and Development Plan (Project No. 2016YFC0802900), the Fundamental Research Funds for the Central Universities (No. 2018BSCXC02), Postgraduate Research and Practice Innovation Program of Jiangsu Province (No. KYCX18_1914), Fire Fighting and Rescue Technology Key Laboratory of MPS Open Project (No. KF201802), Sichuan Science and Technology Project (No. 2018JY0429), National Natural Science Foundation of China (No. 51606215), Natural Science Foundation of Jiangsu Province (No. SBK2016041452), and A Project Funded by the Priority Academic Program Development of Jiangsu Higher Education Institutions (PAPD).
Author information
Authors and Affiliations
Corresponding author
Additional information
Publisher's Note
Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.
Rights and permissions
About this article
Cite this article
Gao, Y., Zhu, G., Zhu, H. et al. Experimental Analysis of Critical Acceleration Condition for Two-Sided Upward Flame Spread Over Inclined Thin Fuel Surfaces. Fire Technol 55, 755–771 (2019). https://doi.org/10.1007/s10694-018-0803-2
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s10694-018-0803-2