LAUSR

When a fire occurs in an aircraft cargo compartment, the fire plume will rise from a different location, intermittently or continuously impact the ceiling, and form a ceiling jet flame at varying heights. Meanwhile, the low-pressure environment within the cargo compartment has a great influence on flame height and high-temperature zone, which could lead to the violent development of ceiling jet fire. Based on this discussion, a series of square oil pan fires were conducted in a full-size cargo compartment located in Kangding airport (altitude 4250 m, atmospheric pressure 61 kPa). Fire behaviors, such as burning rate, flame temperature, flame heights, and smoke gas temperature distribution beneath the ceiling, were measured and analyzed. The experimental results show that as the effective ceiling height decreases, the burning rate of 30 cm square pan fires grows, with a sharp change in the low-pressure environment (50 kPa), where flames impinges on the ceiling. For 20-cm square pan fires, the burning rate at 50 kPa has the same trend with 30 cm, at 75 kPa looks like a parabolic plot, and at 101 kPa shows a continuous dropping. The centerline flame temperature decreases slowly along the axis when the fire occurs at higher height above the floor. Considering the influence of ambient pressure, effective ceiling height, and oil pan size, an empirical correlation for the ceiling transverse smoke temperature distribution is proposed by modifying the current models.