Abstract:Cargo compartment fire has become the major security threat for cruising aircraft that can cause huge property and casualties. The effects of low pressures on common solid fuel fire behavior in air freight was studied using different amounts of corrugated cartons can represent typical Class A solid fuel fires. Mass burning rate, radiative heat flux, and flame axial temperature had been measured as the principal characteristic parameters during the combustion process. The modified B-number theory was employed to model the burning rate behavior of solid fuel. The theoretical relationship between the burning rate and the ambient pressure for a turbulent solid fuel fire is ṁ"∝ ChP2/3+CrP3/2. The experimental results showed that the modified pressure index is 1.3. In addition, the flame radiant heat flux and centerline temperature distribution were analyzed to indicate that the radiant heat flux first increased and then decreased. The radiant heat flux at the R2 location was greater than at other locations. The maximum flame temperatures was 800℃ in the flame zone. The solid fuel fire behavior under reduced pressure environment was investigated from both theoretical and experimental aspects, which provided a basis for aviation fire insurance.
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