Experimental Investigation of the Effects of Fire Size on Burning Characteristics in a Well-Confined Military Vehicle Compartment

This study presents an experimental investigation into the effects of fire size on burning characteristics within well-confined military vehicle engine compartments. The research evaluates burning duration, self-extinguishing phenomena, heat release rates, pressure dynamics, and flame morphology using heptane pool fires of varying pan diameters (8 cm, 16 cm, and 24 cm). Key findings include the proportional relationship between fire size and heat release rate, with larger pans causing higher oxygen consumption, elevated pressure differences, and increased total heat flux. Self-extinguishment was observed for larger pans due to oxygen depletion, with extinction time linked to the ratio of compartment volume to heat release rate. Temperature measurements revealed significantly higher ceiling temperatures and heat flux levels for larger fires, emphasizing the structural and thermal risks. These results contribute to understanding fire behavior in confined spaces, offering practical implications for designing fire protection systems tailored to military vehicles.