Global Equivalence Ratio Concept and the Prediction of Carbon Monoxide Formation in Enclosure Fires

摘要

This report summarizes investigations of the formation of carbon monoxide (CO) in enclosure fires--the most important factor in fire deaths. It contains the first complete review and analysis of the literature available on the global equivalence ratio (GER) concept. The results of a number of recent investigations (including work during the past fiscal year) which were either supported by the BFRL Grants Program or carried out in-house are then discussed. Based on the findings, two completely new mechanisms for the formation of CO, in addition to the quenching of a fire plume by rich upper layer covered by the GER concept, are identified. The first involves reaction of rich flame gases with air which is entrained directly into the high-temperature upper layer of an enclosure fire. The second results from the pyrolysis of oxygenated polymers (such as wood) which are located in a rich, high-temperature upper layer. The findings of these studies form the basis of an analysis which yields the conditions for which use of the GER concept is appropriate for predicting CO formation in enclosure fires.