THERMAL SCIENCE

International Scientific Journal

Jiahao Liu

,

Zhihui Zhou

,

Jian Ang

,

Qimiao Xie

,

Jinhui Wang

,

Richard Yuen

THE MAXIMUM EXCESS TEMPERATURE OF FIRE-INDUCED SMOKE FLOW BENEATH AN UNCONFINED CEILING AT HIGH ALTITUDE

ABSTRACT
Conventional correlations for the maximum temperature under a ceiling were mainly developed based on the experimental results at atmospheric pressure. For high-altitude environment with lower ambient pressure, their feasibility needs to be reexamined. In this paper, a sequence of pool fires with different dimensions and fuel types was performed under a horizontal unconfined ceiling to measure the maximum excess temperature in a high-altitude city, Lhasa (3650 m / 64.3 kPa). The results show that the maximum smoke temperatures beneath the ceiling at high altitude are significant higher than the predicted values by Alpert’s model. Considering the effects of ambient pressure and entrainment coefficient, a new theoretical model for predicting the maximum excess temperature was proposed based on the ideal plume assumption. The current results together with the data in the literature which conform with Alpert’s model successfully converge by employing the proposed correlation.
KEYWORDS
maximum excess temperature, high-altitude environment, pool fire, ceiling jet
PAPER SUBMITTED: 2017-09-26
PAPER REVISED: 2018-02-15
PAPER ACCEPTED: 2018-02-19
PUBLISHED ONLINE: 2018-03-04
DOI REFERENCE: https://doi.org/10.2298/TSCI170926075L
CITATION EXPORT: view in browser or download as text file
THERMAL SCIENCE YEAR 2019, VOLUME 23, ISSUE Issue 5, PAGES [2961 - 2970]
REFERENCES
  1. Dinenno P.J., SFPE handbook of fire protection engineering (3rd edition). Quincy, Massachusetts, USA: National Fire Protection Engineering; 2002
  2. He Y.P. et al., Smoke venting and fire safety in an industrial warehouse, Fire Safety Journal, 37 (2002), pp. 191-215
  3. Byström A. et al., Full-scale experimental and numerical studies on compartment fire under low ambient temperature, Building and Environment, 51 (2012), pp. 255-262
  4. Gutiérrez-Montes C. et al., Experimental data and numerical modeling of 1.3 and 2.3 MW fires in a 20 m cubic atrium, Building and Environment, 44 (2009), pp. 1827-1839
  5. Gutiérrez-Montes C. et al., Numerical model and validation experiments of atrium enclosure fire in a new fire test facility, Building and Environment, 43 (2008), 11, pp. 1912-1928
  6. Ji J. et al., A simplified calculation method on maximum smoke temperature under the ceiling in subway station fires, Tunnelling and Underground Space Technology, 26 (2011), 3, pp. 490-496
  7. Li Y.Z. et al., The maximum temperature of buoyancy-driven smoke flow beneath the ceiling in tunnel fires, Fire Safety Journal, 46 (2011), 4, pp. 204-210
  8. Hu L.H. et al., On the maximum smoke temperature under the ceiling in tunnel fires, Tunnelling and Underground Space Technology, 21 (2006), 6, pp. 650-655
  9. Wang J. et al., Early Stage of Elevated Fires in an Aircraft Cargo Compartment: A Full Scale Experimental Investigation. Fire Technology, 51 (2015), 5, pp. 1129-1147
  10. Wang J. et al., Experiment investigation on the influence of low pressure on ceiling temperature profile in aircraft cargo compartment fires, Applied Thermal Engineering, 89 (2015), pp. 526-533
  11. Chen S.J. et al., Fire detection using smoke and gas sensors, Fire Safety Journal, 42 (2007), 8, pp. 507-515
  12. Alpert R.L., Calculation of response time of ceiling-mounted fire detectors, Fire Technology, 8 (1972), 3, pp. 181-195
  13. Alpert R.L., Turbulent ceiling-jet induced by large-scale fires, Combustion Science and Technology, 11 (1975), 5-6, pp. 197-213
  14. Heskestad G. et al., The initial convective flow in fire, Symposium (International) on Combustion, 17(1979), 1, pp. 1113-1123
  15. Zhou Z.H. et al., Experimental analysis of low air pressure influences on fire plumes, International Journal of Heat and Mass Transfer, 70 (2014), pp. 578-585
  16. Liu J.H. et al., Experimental study on burning behaviors of liquid fuels with different sooting levels at high altitude, Thermal Science, (2016), DOI: 10.2298/TSCI151218100L
  17. Wang Y. et al., Fire detection model in Tibet based on grey-fuzzy neural network algorithm, Expert Systems with Applications, 38 (2011), 8, pp. 9580-9586
  18. Liu J.H. et al., Investigation of enclosure effect of pressure chamber on the burning behavior of a hydrocarbon fuel, Applied Thermal Engineering, 101 (2016), pp. 202-216
  19. Hamins A. et al., Heat feedback to the fuel surface in pool fires, Combustion Science and Technology, 97 (1994), 1-3, pp. 37-62
  20. Luo M.C. et al., Application of field model and two-zone model to flashover fires in a full-scale multi-room single level building, Fire Safety Journal, 29 (1997), pp. 1-25
  21. Tang F. et al., An experimental investigation on temperature profile of buoyant spill plume from under-ventilated compartment fires in a reduced pressure atmosphere at high altitude, International Journal of Heat and Mass Transfer, 55 (2012), 21, pp. 5642-5649
  22. Karlsson B. et al., Enclosure fire dynamics. Boca Raton, Florida, USA: CRC press; 1999
  23. Heskestad G., Virtual origins of fire plumes, Fire Safety Journal, 5 (1983), 2, pp. 109-114
PDF VERSION [DOWNLOAD]
The maximum excess temperature of fire-induced smoke flow beneath an unconfined ceiling at high altitude

© 2024 Society of Thermal Engineers of Serbia. Published by the Vinča Institute of Nuclear Sciences, National Institute of the Republic of Serbia, 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