Numerical Simulation on Effects of EEC Positions and Heights on Pool Fire Temperature Distribution Characteristics in Engine Fan Cavity

ABSTRACT When leaked fuel encounters heat sources, pool fire scenarios occurring in confined fan cavity threaten engine operation safety. Various obstacles' structures, positions, and heights made pool fire propagation mechanisms complicated. Pool fire plume propagation characteristics were investigated in obstructed fan cavity. Both LES turbulent and mixed fraction diffused flame combustion models were established. Three EEC positions and heights were considered. Grid independences were validated. Effects of EEC positions and heights were examined on fire plume temperature distribution behaviors in fan cavity. The results show that fire plume temperature variations and their distributions agree well with experimental ones. The plume temperature undergoes an increase stage and a quasi‐steady one with oscillations. EEC positions and heights have no evident effects on plume temperature variations at the bottom of the fan cavity. EEC with positions closer to the pool and higher heights hinders the fire propagation along the inner ring, but accelerates the fire plume floating across EEC and increases local temperature at the left side or the top of the fan cavity. EEC absence produces plume propagation at the right side of the fan cavity, makes its local temperature relatively low, and its oscillation more evident. EEC obstruction squeezes flame shapes and has unsymmetrical–symmetrical alternate variations. The fire plume develops rearwards.