Flow induced by a small fire in an aircraft cargo compartment

Abstract

According to Federal Aviation Regulations, fire and smoke detector devices installed in aircraft cargo compartments are required to alarm within the first sixty seconds of fire initiation. Expensive and time consuming in-flight and ground tests are conducted to verify compliance and to grant approval for these detection systems. In an effort to minimize the number of certification tests required, Federal Aviation Administration (FAA) is evaluating computational fluid dynamics (CFD) as a tool to predict fire-induced flow behavior in aircraft cargo compartments. The objective of the present study is to evaluate the predictive abilities of available open-source CFD solvers for the transport of smoke and hot gases due to a small fire source in an enclosure. Numerical simulations are carried out using Fire Dynamics Simulator (FDS) 1 developed by National Institute of Standards and Technology (NIST). The simulation results are compared with an extensive set of data collected from fire tests of the forward cargo compartment of Boeing 707 for three different fire scenarios. The selected metrics for the comparison are the predictions of temperature, light transmission and concentrations of carbon monoxide and carbon dioxide in the first three minutes of the test initiation. Furthermore, model estimates for temperature fields are compared with correlations widely-used and relied upon in the fire research community.