Kinetic modeling of spectra of flames with suppressants

Abstract

mThe phase out of halons in response to the Montreal Protocol and the quest for alternative fire suppressants has focused attention on the current lack of understanding of mechanisms of flame extinction. Challenges to the free-radical scavenging mechanism in which chemical chains in combustion are interrupted have raised serious questions as to why the halons are effective. Low-resolution ultraviolet computer spectroscopy can be used to observe the OH radical and other simple molecules when acted upon by halon or alternative suppressants. However, the physical and chemical interpretation of such observations requires reaction rates leading to the OH radical and other observable molecules in 3-6 eV electronic states. Using a simple kinetics model, we illustrate where major reaction rates to excited states would be helpful to the interpretation of the interaction of suppressants with flames. Quantum chemists could provide a valuable service by providing such rates and helping to assess whether or not flame suppression by free-radical scavenging is a significant mechanism. 0 1995 John Wiley & Sons, Inc.