Advertisement

Numerical study of critical re-entrainment velocity of fire smoke within the street canyons with different building height ratios

  • Quanli Wang
  • TaoTao Zhou
  • Qin Liu
  • Peixiang He
  • Changfa TaoEmail author
  • Qin ShiEmail author
Research Article
  • 40 Downloads

Abstract

Traffic accident may bring vehicle fire in the street canyons. With its high temperature and numerous hazardous materials, the smoke produced by the vehicle fire may cause serious damage to the human body and the properties nearby, such as the glass curtain walls of buildings. The influence of the ambient air flow speed and street aspect ratio on the dispersion of fire smoke in street canyon has been analyzed by FDS software and theoretical analysis in this study. The impact of different windward building heights and different ambient air flow speeds u0 on the fire smoke were investigated. The results show that the fire smoke tilts towards the opposing direction of the ambient air flow within the street canyon, while the ambient air flow is perpendicular to the windward building. The results indicate that the critical re-entrainment velocity decreases at first, and then increases until it attains a constant with the building height ratio H1/H2. Finally, a predictive model of the critical re-entrainment velocity was developed under different building height ratios H1/H2.

Keywords

Critical re-entrainment velocity Building height Street canyon Fire smoke 

Nomenclature

h

The height at an arbitrary point

H1

Windward building height

H2

Leeward building height

\( \dot{Q} \)

Heat release rate

t

Move time of fire smoke in vertical direction

t

Move time of fire smoke in horizontal direction

u

Air flow speed

W

The width of street canyon

y

The vertical distance from building top edge to arbitrary point

z0

The aerodynamic roughness length of the area

Greek symbols

κ

Coefficient

η

Coefficient

ν

The speed of fire smoke in vertical direction

Subscript

0

Ambient

c

Critical

x

The x axis

Notes

Acknowledgments

The work in this study was supported by China Postdoctoral Science Foundation (Grant No. 2018M640582), and the National Natural Science Foundation of China (Grant No. 51408181).

Authors’ contribution

All authors contributed equally in the preparation of this manuscript.

Compliance with ethical standards

Conflict of interest

The authors declare that they have no conflicts of interest.

References

  1. Baker J, Walker HL, Cai XM (2004) A study of the dispersion and transport of reactive pollutants in and above street canyons—a large eddy simulation. Atmos Environ 38:6883–6892CrossRefGoogle Scholar
  2. Boddy JWD, Smalley RJ, Goodman PS, Tate JE, Bell MC, Tomlin AS (2005) The spatial variability in concentrations of a traffic-related pollutant in two street canyons in York, UK–Part II: The influence of traffic characteristics. Atmos Environ 39:3163–3176Google Scholar
  3. Cong HY, Wang XS, Zhu P, Jiang TH, Shi XJ (2017) Improvement in smoke extraction efficiency by natural ventilation through a board-coupled shaft during tunnel fires. Appl Therm Eng 118:127–137CrossRefGoogle Scholar
  4. Drysdale D (1999) An introduction to fire dynamics. John Wiley & Sons, EnglandGoogle Scholar
  5. Dixon NS, Boddy JWD, Smalley RJ, Tomlin AS (2006) Evaluation of a turbulent flow and dispersion model in a typical street canyon in York, UK. Atmos Environ 40:958–972CrossRefGoogle Scholar
  6. Dusica JP, Milan DJB, Nenad VZ (2014) Simulation of wind-driven dispersion of fire pollutants in a street canyon using FDS. Environ Sci Pollut Res 21:1270–1284CrossRefGoogle Scholar
  7. Friday, P. A., Mowrer, F. W. 2001. Comparison of FDS model predictions with FM/SNL fire test data. Natl Insti Stand TechnolGoogle Scholar
  8. Hu LH, Huo R, Yang D (2009) Large eddy simulation of fire-induced buoyancy driven plume dispersion in an urban street canyon under perpendicular wind flow. J Hazard Mater 166:394–406CrossRefGoogle Scholar
  9. Hu LH, Xu Y, Zhu W, Wu L, Tang F, Lu KH (2011) Large eddy simulation of pollutant gas dispersion with buoyancy ejected from building into an urban street canyon. J Hazard Mater 192:940–948CrossRefGoogle Scholar
  10. Hu LH, Zhang XC, Zhu W, Ning Z, Tang F (2015) A global relation of fire smoke re-circulation behavior in urban street canyons. J Civ Eng Manag 21:459–469CrossRefGoogle Scholar
  11. Ji J, Wan HX, Li KY, Han JY, Sun JH (2015) A numerical study on upstream maximum temperature in inclined urban road tunnel fires. Int J Heat Mass Transf 88:516–526CrossRefGoogle Scholar
  12. Ji J, Gao Z, Fan C, Sun J (2013) Large eddy simulation of stack effect on natural smoke exhausting effect in urban road tunnel fires. Int J Heat Mass Transf 66:531–542CrossRefGoogle Scholar
  13. Li LX, Wang JS, Tu XD, Liu W, Huang Z (2007) Vertical variations of particle number concentration and size distribution in a street canyon in Shanghai, China. Sci Total Environ 378:306–316CrossRefGoogle Scholar
  14. Li XX, Liu CH, Leung DYC (2009) Numerical investigation of pollutant transport characteristics inside deep urban street canyons. Atmos Environ 43:2410–2418CrossRefGoogle Scholar
  15. McCaffrey BJ 1979. Purely buoyant diffusion flames: some experimental results. NBSIR, 79–1910Google Scholar
  16. McGrattan KB, Hostikka S, Floyd JE, Baum HR, Rehm RG, Mell WE, McDermott R. (2010) Fire dynamics simulator (version 5), technical reference guide, volume 1: mathematical model. NIST Special Publication 1018-5, National Institute of Standards and Technology, Gaithersburg, MarylandGoogle Scholar
  17. McGrattan KB, Mcdermott R, Floyd J, Hostikka S, Forney G, Baum H (2012) Computational fluid dynamics modelling of fire. Int J Comput Fluid D 26:349–361CrossRefGoogle Scholar
  18. McGrattan KB, Hostikka S, Mcdermott R, Floyd J, Weinschenk C, Overholt K 2013. Fire dynamics simulator, user’s guide. NIST Special PublicationGoogle Scholar
  19. Moin P, Squires K, Cabot W, Lee S (1991) A dynamic subgrid-scale model for compressible turbulence and scalar transport. Phys Fluids A: Fluid Dynam 3:2746–2757CrossRefGoogle Scholar
  20. Nicholson SE (1975) A pollution model for street-level air. Atmos Environ 9:19–31CrossRefGoogle Scholar
  21. Oke TR (1988) Street design and urban canopy layer climate. Energ Build 11:103–113CrossRefGoogle Scholar
  22. Park SK, Kim SD, Lee HK (2004) Dispersion characteristics of vehicle emission in an urban street canyon. Sci. Total Environ 323:263–271Google Scholar
  23. Pavageau M, Schatzmann M (1999) Wind tunnel measurements of concentration fluctuations in an urban street canyon. Atmos Environ 33:3961–3971CrossRefGoogle Scholar
  24. Quintiere JG (2006) Fundamentals of fire phenomena. John Wiley & Sons, EnglandCrossRefGoogle Scholar
  25. Robert NM, Douglas WH, Russ D, Jim S, Ken W, Peter G (2015) CFD simulation of ventilation and smoke movement in a large military firing range. J Wind Eng Ind Aerodyn 136:12–22CrossRefGoogle Scholar
  26. Salizzoni P, Grosjean N, Mejean P, Perkins RJ, Soulhac L, Vanliefferinge R (2007) Wind tunnel study of the exchange between a street canyon and the external flow. Air Poll Model Its Appli XVII:430–437Google Scholar
  27. Sun, X. Q. 2009. Studies on smoke movement and control in shafts and stairwell in high-rise buildings, PhD Thesis, University of Science and Technology of China, Hefei, Anhui, China, 2009Google Scholar
  28. Tan W, Li CJ, Wang K, Zhu GR, Wang Y, Liu LY (2018) Dispersion of carbon dioxide plume in street canyons. Process Saf Environ 116:235–242CrossRefGoogle Scholar
  29. Tan W, Li CJ, Wang K, Zhu GR, Liu LY (2019) Geometric effect of buildings on the dispersion of carbon dioxide cloud in idealized urban street canyons. Process Saf Environ 122:271–280CrossRefGoogle Scholar
  30. Xie S, Zhang Y, Qi L, Tang X (2003) Spatial distribution of traffic-related pollutant concentrations in street canyons. Atmos Environ 37:3213–3224CrossRefGoogle Scholar
  31. Zhao WF, Zong RW, Liu JH, Ye JN, Zhu KJ (2015) Study of the fire characteristics for multi-source fires in the confined corridor. J Wind Eng Ind Aerodyn 147:239–250CrossRefGoogle Scholar
  32. Zhang BS, Zhang JQ, Lu SX, Li CH (2015)Buoyancy-driven flow through a ceiling aperture in a corridor: a study on smoke propagation and prevention. Build Simul 8:701–709CrossRefGoogle Scholar
  33. Zhong W, Fan CG, Ji J, Yang JP (2013a) Influence of longitudinal wind on natural ventilation with vertical shaft in a road tunnel fire. Int J Heat Mass Transf 57:671–678CrossRefGoogle Scholar
  34. Zhong W, Lv JJ, Li ZZ, Liang TS (2013b) A study of bifurcation flow of fire smoke in tunnel with longitudinal ventilation. Int J Heat Mass Transf 67:829–835CrossRefGoogle Scholar
  35. Zhang XC, Zhang ZJ, Su GK, Tao HW, Xu WH, Hu LH (2019) Buoyant wind-driven pollutant dispersion and recirculation behavior in wedge-shaped roof urban street canyons. Environ Sci Pollut Res 26:8289–8302CrossRefGoogle Scholar

Copyright information

© Springer-Verlag GmbH Germany, part of Springer Nature 2019

Authors and Affiliations

  1. 1.School of Automotive and Transportation EngineeringHefei University of TechnologyHefeiChina
  2. 2.School of Civil EngineeringHefei University of TechnologyHefeiChina

Personalised recommendations