Experimental investigation on characteristic parameters of thermal fields for weak-plume travelling fire in a full-length confined corridor

The occurrence of cable fire is one of the highest fire hazards in the nuclear power plant. The fire scenario of the cable fire in the corridor that cable flame spread along cable tray can be considered as traveling fires in the confined space. The smoke layer was accumulated at upper zone in the confined space and had an important impact on fire dynamics, particularly for weak-plume traveling fires in confined spaces. Therefore, in this study, fire experiments on gas fuel flames moving at different speeds in a full-length corridor were conducted. The use of gas fuel decouples the interaction between the gas and solid phases. A critical speed was observed for the effect of the movement of the fire source on the upper smoke layer and ceiling jet flow. A traveling fire with a low speed generated a higher maximum upper layer and ceiling jet temperature than that with a high speed. Considering the effect of the accumulated smoke layer, an improved method of fire risk analysis was designed for weak-plume traveling fires in confined spaces. Compared with previous models, the improved method in this study can accurately predict the maximum ceiling jet temperatures. Then, the improved method enables accurate prediction of fire risk resulting from weak-plume traveling fires in confined spaces.