01. Experimental/Computational Fluid Dynamics

Aircraft Cargo compartment fire is one of the main threats to the safety of civil aircraft. In this study, the effects of spray angle and nozzle layout of water mist system in cargo compartement were indicated through the numerical simulation. The fire dynamics simulation code (FDS) was used to simulation the fire suppression scenario of full-scale aircraft cargo compartment. The results show that the extinguishment time of corner fire is larger compared with center and sidewall fire. This is due that the relative larger distance from the nozzle, the effective amount of droplets into the flame area is less. The spray angle affects the water coverage in the fire zone. For fixed flow rate, the water mist flux distribution has strong correlation, the larger spray angle, the smaller mist flux value. When the droplet size varies from 50 to 400μm, the fire extuigshingment time first increase and then decrease, the corresponding dominant mechanism of smothering effect with small droplet and the cooling effect of large droplet. The nozzle layout affects the whole water covrage on the ground of cargo compartment. With the increase of nozzle numbers, the water mist flux is more evenly distributed and the fire extinguishment effect will also increase.