Smoke data determination for various types of fuel

Fire protection assessment is of major interest in industrial environments. Among the resulting threats, smoke production is the object of growing attention. In this context, a proper analysis of smoke generated by four of the most commonly used oils in the Electricite de France production units, as well as heating oil, often implicated in everyday life accidental fires, is reported. The convenient relative measure of smoke emission, the specific extinction area, is identified as the variable to be used. Results show that all these fuels have a high propensity to generate soot particles. The evolution of extinction coefficient and wavelength, modelled as K(e)similar to lambda(-n), reveals small-size, mainly absorbing particles. However, the dispersion coefficient n appears not spectrally constant. Despite the few data points, giving an exploratory nature to the work, a slope discontinuity of the curves, more or less marked as a function of the atomic ratio H/C of the fuel, appears between the visible and near infrared range of the spectrum. Theoretical predictions using appropriate values of soot optical constants show a satisfactory agreement with experiment. Beyond a simple classification of the different fuels, the results are valuable as input values in radiative exchange modelling. (C) 1998 Published by Elsevier Science Ltd. All rights reserved.