Smoke oxidation kinetics for application to prediction of clean burn patterns

Abstract

SUMMARY Smoke deposition patterns are a potentially rich source of information concerning the behavior of a fire. Clean burn patterns are smoke‐free areas where smoke deposits have been oxidized away. In order to predict the formation of clean burn patterns, smoke oxidation kinetics are required. Smoke oxidation kinetics were studied for smokes from acrylonitrile butadiene styrene, polymethylmethacrylate, polypropylene, and gasoline. The fuels were burned below a hood, and smoke samples were collected from the hot gas layer and from the wall surfaces. The smokes from various polymers and gasoline were found to contain no measurable volatile organic chemicals. The kinetics of the smokes from the polymers and gasoline were found to be satisfactorily modeled as first order in both smoke and oxygen with the same kinetic constants for all fuels tested. The activation energy was calculated to be 211 kJ/mol, and the pre‐exponential factor was found to be 4.7 × 1010/s. These kinetic parameters provide a basis for modeling clean burn pattern generation. Copyright © 2011 John Wiley & Sons, Ltd.

Experimental Study of Carbon Black and Diesel Engine Soot Oxidation Kinetics Using Thermogravimetric Analysis

“…In general, the range of activation energies reported in the literature for the oxidation of carbon black and soot samples is 100–300 kJ/mol. ,,,,,,,,,,− However, the typically reported activation energies for diesel engine soot oxidation are in the range of 120–180 kJ/mol. ,,,,− Neeft et al suggested that the activation energy increased in the following sequence: soot < activated carbon < carbon and chars < graphite, which was also observed in our experiments, with graphite showing the largest activation energy and the smallest rate constant. Given the comprehensive nature of our study, literature data were not available for direct comparisons for all of the samples studied; however, the activation energies estimated from our TGA experiments were in close agreement with those reported in the literature.…”

“…Estimation of kinetic parameters from TGA data can be performed using various approaches, as recommended by the Kinetics Committee of the International Confederation for Thermal Analysis and Calorimetry (ICTAC). 18 However, the most widely used approach for kinetic parameter estimation from soot or carbon black oxidation is based on the Arrhenius equation format 20,47,48…”

“…Estimation of kinetic parameters from TGA data can be performed using various approaches, as recommended by the Kinetics Committee of the International Confederation for Thermal Analysis and Calorimetry (ICTAC) . However, the most widely used approach for kinetic parameter estimation from soot or carbon black oxidation is based on the Arrhenius equation format ,, − d m d t = k m n p O 2 r = A exp true( prefix− E normala R T true) m n p O 2 r where m is the instantaneous sample mass at time t , k is the reaction rate constant, A is the pre-exponential factor, E a is the activation energy, T is the operating temperature, p O 2 is the partial pressure of oxygen, and n and r are the reaction orders for carbon and oxygen, respectively. It is known that the surface area of the carbonaceous samples increases during oxidation .…”

Fire dynamics simulator modeling of a line-of-duty death in a firefighting training facility using recent research on materials and firefighter safety

“…The region extended west of the beam by distance similar to the width of the beam. As part of soot deposition work performed for the National Institute of Justice, Hartman et al 25 performed thermogravimetric analysis (TGA) measurements for soot at different oxygen concentrations. At 21% oxygen, clean burn ends at approximately 650°C, approximately 675°C at 10% oxygen, and approximately 730°C at 2%.…”

Development and Application of an Intelligent Approach to Reconstruct the Location of Fire Sources from Soot Patterns Deposited on Walls

“…Incomplete combustion creates soot particles and is typical in a compartment fire, which lacks oxygen due to poor air entrainment into the reaction zone of the fire's flame. The mechanisms of smoke deposition include diffusion, sedimentation, inertial impaction, turbulent diffusion, and thermophoresis, with the latter being dominant [29]. Ciro et al [30] investigated soot deposition due to thermophoretic action by immersing cooled and uncooled cylinders into a fire and measuring the soot deposition rates.…”