- Author
-
Molina, M. G. O.
- Title
- Experimental Investigation of Smoldering Combustion of Cellulosic Materials.
- Coporate
- Massachusetts Institute of Technology, Cambridge
- Report
-
Thesis
August 9, 1976
127 p.
- Keywords
-
cellulosic materials
|
smoldering combustion
|
experiments
|
extinguishment
|
environmental effects
|
oxygen concentration
- Identifiers
- environment and fuel characteristics; cotton thread
- Abstract
- Experiments were conducted to examine the effects of environment and fuel characteristics on the smoldering behavior of cylindrical samples of cotton. Environments of Nitrogen-Oxygen, Helium-Oxygen and Argon-Oxygen, with different oxygen partial pressures and mole fractions were employed. Samples of cotton thread with densities varying from 0.06 gr/cm³ to 0.8 gr/cm³, and diameters from 0.04 cms to 3.5 cms were tested. Depending on the environment and the fuel characteristics three regimes of smoldering were observed: steady smoldering, transition to flame, and transition to extinguishment. For the case of steady smoldering theoretical calculations were performed, using a recently developed theoretical model of smoldering. These calculations seem to agree well with the experimental results. In the non-steady cases it was found that helium has a strong effect in the extinguishment and flaming limits found in N₂-O₂ environments. In He-O₂ environments the extinguishment limit conditions are found at much higher oxygen concentrations than in N₂-O₂ environments. Experiments in He-N₂-O₂ environments indicate that helium has an effect on the extinguishment limit. Then the possibility of using helium as an extinguishant for smoldering fires is examined and it is compared to other existing procedures of fire extinguishment.