Skip to main content
Log in

Study on the role of soot and heat fluxes in upward flame spread using a wall-resolved large eddy simulation approach

  • Published:
Journal of Thermal Analysis and Calorimetry Aims and scope Submit manuscript

Abstract

The present study aims to obtain further understandings of vertical flame spreading phenomena by analysing the influences of soot and individual heat flux components on PMMA walls using large eddy simulation. Total heat flux consists of convective and radiative components, but it is not clear which one has a significant role in fire spread. The computational code used is an in-house version of FireFOAM 2.2.x, which has recently undergone specific development and validation for flame spread studies by the authors. The present study has conducted numerical simulations for flame spread and full wall fire configurations. By scale-up of the PMMA size from 0.4 to 1.0 m, the convective heat flux decreased by 41.4% at the location of the pyrolysis front, radiative heat flux increased by 86.9%, and radiative heat flux due to soot grew by 215.2%. As the pyrolysis height increases from 0.3 to 1.0 m, the convective heat flux decreased by 26.8% at the location of the pyrolysis front. The radiative heat flux increased by 96.8%, and its components of combustion of the gaseous fuel and soot grew by 55.9% and 233.3%, respectively. Moreover, the ratio of radiative heat flux to total heat flux increased by 66.5%, and that of soot to radiative heat flux grew by 73.9%. The contribution of soot to radiative heat flux almost linearly increased against the pyrolysis height and that was higher at a higher pyrolysis height.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Fig. 1
Fig. 2
Fig. 3
Fig. 4
Fig. 5
Fig. 6
Fig. 7
Fig. 8
Fig. 9
Fig. 10
Fig. 11
Fig. 12
Fig. 13
Fig. 14
Fig. 15
Fig. 16
Fig. 17
Fig. 18
Fig. 19
Fig. 20

Similar content being viewed by others

Abbreviations

a rad :

Absorption coefficient (1 m−1)

A :

Frequency factor (unit is dependent on a equation)

Cp:

Specific heat at constant pressure (J K−1 kg−1)

C D2 :

Model constant of the eddy dissipation concept

C S :

Smagorinsky constant

C w :

Model constant of wall adapting local eddy viscosity model

d :

Wall thickness (m)

E :

Activation energy (kJ mol−1)

Err:

Error (%)

f v :

Soot volume fraction

h :

Enthalpy (J kg−1)

h :

Enthalpy of formation (J kg−1) or (J mol−1)

Δh comb :

Heat of combustion (J kg−1) or (J mol−1)

H :

PMMA height (m)

k :

(Total) turbulent kinetic energy (m2 s2)

mʺ:

Local pyrolysis rate (kg s−1 m2)

\(\dot{m}^{*}\) :

Mass transfer rate between fine structure and surrounding fluids (kg s−1)

p :

Pressure (Pa)

Pr t :

Turbulent Prandtl number

:

Heat release rate scaled by wall width (W m−1)

:

Heat flux (W m2). Section 2.5.1 presents several definitions.

r rad :

Reflectivity

R :

Gas constant (kJ mol−1 K−1)

R 0 :

Criterion of flame volume

s :

Stoichiometric oxygen-fuel mass ratio

S S :

Soot particulate surface area (m2 kg−1)

Sc t :

Turbulent Schmidt number

t :

Time (s)

T :

Temperature (K)

T a :

Activation temperature (K)

W :

PMMA width (m)

x, y, z :

Coordinates (m) or the number of elements C, H, and O in a chemical equation

x p :

Pyrolysis height (m)

x f :

Flame height (m)

x wall :

Distance from the bottom leading edge of PMMA (m)

y standoff :

Standoff distance (m)

Y :

Mass fraction

Z:

Mixture fraction

γ :

Mass fraction of fine structures

ε :

(Total) dissipation rate (m2 s−3)

ε rad :

Emissivity

η rad :

Transmissivity

y wall :

Width of grid cell next to wall (mm)

λ :

Heat conductivity (W K−1 m−1)

ν :

Kinematic viscosity (m2 s−2)

ξ :

Criterion of flame regions

ω :

Reaction/pyrolysis rate (kg s−1 m3)

ρ :

Density (kg m3)

σ Stefan :

Stefan–Boltzmann constant (W m−2 K−4)

τ :

Timescale (s)

τ η :

Kolmogorov timescale (s)

\(\phi\) :

Equivalence ratio

χ :

Reaction fraction in the fine structures

chem:

Chemical reaction

conv:

Convection

diff:

Diffusion

EDC:

Eddy dissipation concept

em:

Emitted

fu:

Fuel

first:

First cell

gas:

Gas/gasification

integ:

Integral

inter:

Interface

J :

Chemical species

mel:

Melting

mod:

Modified

net:

Net

ox:

Oxidiser or oxygen

p:

Pyrolysis

pr:

Product

rad:

Radiation/radiative

refl:

Reflective

res:

Revolved

solid:

Solid

S/soot:

Soot

SGS:

Sub-grid scale

tot:

Total

vap:

Vaporisation

wall:

Wall

0:

Reference or standard value

*:

Fine structures

0:

Surrounding fluids

\(\overline{\phi }\) :

Time average variable

\(\tilde{\phi }\) :

Density-weighted average variable

References

  1. Fukumoto K, Wang CJ, Wen JX. Large eddy simulation of upward flame spread on PMMA walls with a fully coupled fluid-solid approach. Combust Flame. 2018;190:365–87.

    Article  CAS  Google Scholar 

  2. Drysdale D. Flame spread on inclined surfaces. Fire Saf J. 1992;18:245–54.

    Article  CAS  Google Scholar 

  3. Orloff L, de Ris J, Markstein GH. Upward turbulent fire spread and burning of fuel surface. Proc Combust Inst. 1975;15:183–92.

    Article  CAS  Google Scholar 

  4. Tsai KC. Influence of sidewalls on width effects of upward flame spread. Fire Saf J. 2011;46:294–304.

    Article  CAS  Google Scholar 

  5. Hasemi Y. Experimental wall flame heat transfer correlations for the analysis of upward wall flame spread. Fire Sci Technol. 1984;4:75–90.

    Article  CAS  Google Scholar 

  6. Liang C, Cheng X, Yang H, Zhang H, Yuen KK. Experimental study of vertically upward flame spread over polymethyl methacrylate slabs at different altitudes. Fire Mater. 2016;40:472–81.

    Article  CAS  Google Scholar 

  7. Singh AV, Gollner MJ. Experimental methodology for estimation of local heat fluxes and burning rates in steady laminar boundary layer diffusion flames. Combust Flame. 2015;162:2214–30.

    Article  CAS  Google Scholar 

  8. Consalvi JL, Pizzo Y, Porterie B. Numerical analysis of the heating process in upward flame spread over thick slabs. Fire Saf J. 2008;43:351–62.

    Article  CAS  Google Scholar 

  9. Karpov A, Shaklein A, Korepanov M, Galat A, Numerical study of the radiative and turbulent heat flux behavior of upward flame spread over PMMA. Fire Sci Technol. 2017;2015:841–848.

  10. Zeinali D, Gupta A, Maragkos G, Agarwal G, Beji T, Chaos M, Wang Y, Degroote J, Merci B. Study of the importance of non-uniform mass density in numerical simulations of fire spread over MDF panels in a corner configuration. Combust Flame. 2019;200:303–15.

    Article  CAS  Google Scholar 

  11. Liao YTT, T’ien JS. A numerical simulation of transient ignition and ignition limit of a composite solid by a localised radiant source. Combust Theor Model. 2013;17:1096–124.

    Article  CAS  Google Scholar 

  12. Zhao X, T’ien JS. A three-dimensional transient model for flame growth and extinction in concurrent flows. Combust Flame. 2015;162:1829–39.

    Article  CAS  Google Scholar 

  13. FM Global, FireFOAM 2.2.x, https://github.com/fireFoam-dev/fireFoam-2.2.x. Accessed 07 Jun 2019

  14. OpenFOAM Ltd., OpenFOAM, Source code and documentations are available from: http://www.openfoam.com/. Accessed 07 Jun 2019

  15. Chen Z, Wen J, Xu B, Dembele S. Extension of the eddy dissipation concept and smoke point soot model to the LES frame for fire simulations. Fire Saf J. 2014;64:12–26.

    Article  CAS  Google Scholar 

  16. Chen Z, Wen J, Xu B, Dembele S. Large eddy simulation of a medium-scale methanol pool fire using the extended eddy dissipation concept. Int J Heat Mass Trans. 2014;70:389–408.

    Article  Google Scholar 

  17. Wang CJ, Wen JX, Chen ZB. Simulation of large-scale LNG pool fires using FireFoam. Combust Sci Technol. 2014;186:1632–49.

    Article  CAS  Google Scholar 

  18. Pizzo Y, Lallemand C, Kacem A, Kaiss A, Gerardin J, Acem A, Boulet P, Porterie B. Steady and transient pyrolysis of thick clear PMMA slab. Combust Flame. 2015;162:226–36.

    Article  CAS  Google Scholar 

  19. Huang X, Gollner MJ. Correlations for evaluation of flame spread over an inclined fuel surface. In: Fire safety science-proceedings of the eleventh international symposium. 2014. p. 222–33.

  20. Hebert D, Coppalle A, Talbaut M. 2D soot concentration and burning rate of a vertical PMMA slab using laser-induced incandescence. Proc Combust Inst. 2013;34:2575–82.

    Article  CAS  Google Scholar 

  21. Ren N, Wang Y, Vilfayeau S, Trouvé A. Large eddy simulation of vertical turbulent wall fires. Combust Flame. 2016;169:194–208.

    Article  CAS  Google Scholar 

  22. Maragkos G, Beji T, Merci B. Advances in modelling in CFD simulations of turbulent gaseous pool fires. Combust Flame. 2017;181:22–38.

  23. Nicoud F, Ducros D. Subgrid-scale stress modelling based on the square of the velocity gradient tensor. Flow Turbul Combust. 1999;62:183–200.

    Article  CAS  Google Scholar 

  24. Fernández-Tarrazo E, Sánchez AL, Liñán A, Williams FA. A simple one-step chemistry model for partially premixed hydrocarbon combustion. Combust Flame. 2006;147:32–8.

    Article  Google Scholar 

  25. Smith TF, Shen ZF, Frledman JN. Evaluation of coefficients for the weighted sum of gray gases model. J Heat Trans. 1982;104:602–8.

    Article  CAS  Google Scholar 

  26. Wang CJ, Liu HR, Wen JX. An improved PaSR-based soot model for turbulent fires. Appl Therm Eng. 2018;129:1435–46.

    Article  CAS  Google Scholar 

  27. Fukumoto K, Wang CJ, Wen JX. Supplemental materials for 'Study on the role of soot and heat fluxes in upward flame spread using a wall resolved large eddy simulation approach'. doi.org/https://doi.org/10.17632/drtddfyvzc.1, Accessed 21 Sep 2019.

  28. Poling BE, Prausnitz JM, O’Connel JP. The properties of gases and liquids. 5th ed. USA: McGraw-Hill; 2001.

    Google Scholar 

  29. Burcat A. Thermochemical species in polynomial form, https://burcat.technion.ac.il/dir/. Accessed 3 Apr 2019

  30. Fukumoto K, Wang CJ, Wen JX. Large eddy simulation of a syngas jet flame: effect of preferential diffusion and detailed reaction mechanism. Energy Fuels. 2019;33:5561–81.

    Article  CAS  Google Scholar 

  31. Gran IR, Magnussen BF. A numerical study of a bluff-body stabilized diffusion flame. Part 2. Influence of combustion modeling and finite-rate chemistry. Combust Sci Technol. 1996;119:191–217.

    Article  CAS  Google Scholar 

  32. Yao W, Zhang J, Nadjai A, Beji T, Delichatsios MA. A global soot model developed for fires: validation in laminar flames and application in turbulent pool fires. Fire Saf J. 2011;46:371–87.

    Article  CAS  Google Scholar 

  33. Lee KB, Thring MW, Beér JM. On the rate of combustion of soot in a laminar soot flame. Combust Flame. 1962;6:137–45.

    Article  CAS  Google Scholar 

  34. Leung KM, Lindstedt RP, Jones WP. A simplified reaction mechanism for soot formation in nonpremixed flames. Combust Flame. 1991;87:289–305.

    Article  CAS  Google Scholar 

  35. Chaos M, Khan MM, Krishnamoorthy N, de Ris JL, Dorofeev SB. Evaluation of optimization schemes and determination of solid fuel properties for CFD fire models using bench-scale pyrolysis tests. ProcCombust Inst. 2011;33:2599–606.

    Article  CAS  Google Scholar 

  36. Staggs J. The effects of gas-phase and in-depth radiation absorption on ignition and steady burning rate of PMMA. Combust Flame. 2014;161:3229–36.

    Article  CAS  Google Scholar 

  37. Beard AN. Flashover and boundary properties. Fire Saf J. 2010;45:116–21.

    Article  CAS  Google Scholar 

  38. Orloff L, Modak AT, Alpert RL. Burning of large-scale vertical surface. Symp (Int) Combust. 1977;16:1.

    Article  Google Scholar 

  39. Pope SB. Ten questions concerning the large-eddy simulation of turbulent flows. New J Phys. 2004;6:1–24.

    Article  Google Scholar 

  40. de Ris JL, Markstein GH, Orloff L, Beaulieu PA. Similarity of turbulent wall fires. Fire Saf Sci. 2003;7:259–70.

    Article  Google Scholar 

  41. de Wilde JP. The heat of gasification of polyethylene and polymethylmethacrylate, Memorandum M-593, Report PML 1988 C42, SFCC Publication No. 53, Delft University of Technology, 1988.

  42. Yang W, Wlodzimierz B. Numerical study of fuel temperature influence on single gas jet combustion in highly preheated and oxygen deficient air. Energy. 2005;30:385–98.

    Article  CAS  Google Scholar 

  43. Wang Y, Chatterjee P, de Ris JL. Large eddy simulation of fire plumes. Proc Combust Inst. 2011;33:2473–80.

    Article  CAS  Google Scholar 

  44. Fukumoto K, Ogami Y. Turbulent diffusion combustion model using chemical equilibrium combined with the eddy dissipation concept for reducing detailed chemical mechanisms: an application of H2-air turbulent diffusion flame. Heat Transf - Asian Res. 2010;39(5):292–313.

    Google Scholar 

  45. Quintiere J, Harkleroad M, Hasemi Y. Wall flames and implications for upward flame spread. Combust Sci Technol. 1986;48:191–222.

    Article  CAS  Google Scholar 

  46. Tsai KC. Width effect on upward flame spread. Fire Saf J. 2009;44:962–7.

    Article  CAS  Google Scholar 

  47. Walters RN, Hackett SM, Lyon RE. Heats of combustion of high temperature polymers. Fire Mater. 2000;24:245–52.

    Article  CAS  Google Scholar 

Download references

Acknowledgements

FireFOAM 2.2.x was built and distributed by FM Global, and the authors acknowledge technical and help supports from them. The in-house version of FireFOAM used in this study firstly developed in the project funded by the National key research and development program special for inter-governmental cooperation (No. 2016YFE0113400) and the European Commission FP7-PEOPLE-2012-IIF (Grant number 328784).

Author information

Authors and Affiliations

Authors

Corresponding authors

Correspondence to Changjian Wang or Jennifer X. Wen.

Additional information

Publisher's Note

Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Appendix

Appendix

The readers can find a document about flame spread modelling and associated animation files from https://doi.org/10.17632/drtddfyvzc.1.

Rights and permissions

Reprints and permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Fukumoto, K., Wang, C. & Wen, J.X. Study on the role of soot and heat fluxes in upward flame spread using a wall-resolved large eddy simulation approach. J Therm Anal Calorim 147, 4645–4665 (2022). https://doi.org/10.1007/s10973-021-10791-6

Download citation

  • Received:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1007/s10973-021-10791-6

Keywords

Navigation