Experimental study of radiative heat transfer in a translucent fuel sample exposed to different spectral sources

Abstract : Radiative heat transfer to a solid is a key mechanism in fire dynamics, and in-depth absorption is especially of importance for translucent fuels. The sample-heater interaction for radiative heat transfer is experimentally investigated in this study with two different heaters (electric resistance and tungsten lamp) using clear PolyMethylMethAcrylate (PMMA) samples from two different formulations (Plexiglass and Lucite). First, the significant effects of the heater type and operating temperature on the radiative heat transfer are revealed with broadband measurements of transmittance on samples of different thicknesses. Then, the attenuation coefficient in Beer–Lambert’s law has been calculated from detailed spectral measurements over the full wavelength range encountered in real fires. The measurements present large spectral heterogeneity. These experimental results and calculation of in-depth absorption are used to explain the reason behind the apparent variation of the fuel absorbance with the sample thickness observed in past studies. The measurement of the spectral intensity emitted by the heaters verifies that the common assumption of blackbody behavior is correct for the electric resistance, whereas the tungsten lamp does not even behave as a greybody. This investigation proofs the necessity of a multi-band radiation model to calculate accurately the fire radiative heat transfer which affects directly the in-depth temperature profiles and hence the pyrolysis process for translucent fuel.
Keywords : Radiation
Type de document :
Article dans une revue
International Journal of Heat and Mass Transfer, Elsevier, 2013, 61, pp.742 - 748. 〈10.1016/j.ijheatmasstransfer.2013.02.017〉
Liste complète des métadonnées

https://hal.univ-lorraine.fr/hal-01427463
Contributeur : Lemta Ul <>
Soumis le : jeudi 5 janvier 2017 - 16:59:52
Dernière modification le : mardi 16 janvier 2018 - 17:56:01

Lien texte intégral

Identifiants

Collections

Citation

N. Bal, J. Raynard, G. Rein, J.L. Torero, M. Försth, et al.. Experimental study of radiative heat transfer in a translucent fuel sample exposed to different spectral sources. International Journal of Heat and Mass Transfer, Elsevier, 2013, 61, pp.742 - 748. 〈10.1016/j.ijheatmasstransfer.2013.02.017〉. 〈hal-01427463〉

Partager

Métriques

Consultations de la notice

63